C Highway_Safety_Design_and_Operations 390p.pdf

HIGHWAY SAFETY, DESIGN AND OPERATIONS
Roadside Hazards
J'llIDAY, TO'NE 23, 1967
Hom,E oF REPRERENTATIVF.S,
Sr1-:cu1, SuncoMMITTEE oN THE
FEDER,L-AID HIGHWAY PRooRAM OFTHE
CoMMITIEE ON PuBLIC WoRKs,
Washington,D.O.
The subcommittee met, p11rs111rnt to adjoumment, at 10 :58 a.m., in
room 2167, Rayburn Building, Hon. William H. Harsha (acting
chairman) pres1ding.
Present: Messrs. McCarthv and Har.-ha.
Staff present: Same as predous days.
Mr. HARSHA. The Spccial Suhcommitt.ee on the Federal-Aid High
way Program will please come to or<ler.
,ve continue to harn with us this morning the panel of experts
in the highway enginecring field whose advice and comments have
been so helpful to us at our puhlic hearings this week. These gentle
men are perfonning a grent S<'rvice to the subcommittee, and to their
fel)ow Americans, by making nrnilable to us their expertise and ex
perience in analyzing nnd discussing design snfety feature,s found
m recently opened lnten<tate proje,cts selected from various sections
of the country.
We will continue this morning with that discussion.
You may proceed, gentlemen.
l'URTRER TESTIMONY OF CHARLES W. PRISX, DEPOTY DIRECTOR,
OFFICE OF TRAFFIC OPERATIONS, BUREAU OF PUBLIC ROADS;
1.&XES E. WILSON, TllAFFIC ENGINEER, CALIFORNIA DIVISIOJf
OF HIGHWAYS; EDMUND R. RICKER, DIRECTOR, BU1l.EAU OF
TRAFFIC, PENNSYLVANIA DEPARTMENT OF HIGHWAYS; PAUL
SKEELS, CHAIRMAN OF COMMI'ITEE ON GUARDRA.IL, HIGHWAY
BXSEARC:O: BOARD; T. S. HUFF, CHIEF ENGIXEER OF TEXAS
HIGHWAY DEPARTMENT; W. J'ACK WILKES, CHIEF OF BRIDGE
DIVISIOJf, OFFICE OF ENGINEERING AND OPERATIONS, BU1l.EAU
OF PUBLIC ROADS-PANEL
. Mr. CoNSTANDY. 1fr. Chairman, we are presse<l for time and I would
hke to ask Mr. Prisk if he could quickly f!º through the slides which
cover the remaining three elements that we have--drainage, shoulders,
and slope,s.
I would like to ask if the members of the panel might perhaps jot
down notes as we go through each section. As we complete it, perhaps
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you could give your cornrnents then. We can conserve sorne time this
wa.y.
Mr. Prisk, if you will please quickly go through the rema.ining
slides.
Mr. PRISK. Thank you, Mr. Constandy a.nd gentlernen of the com
mittee.
These are slides first tha.t relate to drainage features of the highway.
At the top you will see t.he undesirable condit.ion of an exposed
headwall at the left and median inlet raised in the right hand. The
lower pa.rt shows the more desirable condition where these drainage
features are flush with the surrounding ground.
DRA AGE FEATURES
IIUDWALL
UISII _.. IIIUT
X
SL6PED no SECTION
------
Now to look at sorne of the conditions that we saw. This is on an
Ohio project, interstate, where the median is huilt flush with sur
roundmg ground.

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Here is a drainage feature at an intel"Btate aepan.tion in Ohio where
someobstruction isoft'ered atthe roadside.
Here now in Nevada we find an exposed median drain built well
above the surrounding surface. This 1s truly an obstruction to any
traffic in that area.
Mr. CoNBTANDY. This is in Nevada, Mr. Prisk'
Mr. Pmsx.. Yes.
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Still another picture in Nevada, a cross-drain headwall.
Here now in Oklahoma is a paved median with a surface drain. lt
serves very nicely t.o handle drainage and offers no obstruction to
traffic flow.
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Still another one on a new project just outside of Oklahoma. City,
noty«t. opened, another kind of a dra.in on a rural section.
Here is one in Montana which does project above the roe.dway
surfaoe in the median.
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AJso in Montana, we find this desirable cutoff' culvert, which fits
in with the slope profile.
Here is another view of a drainage pi1;>
e extendin9. out the side, a.lso
in Montana, where there is sorne hazard mvolved. lt s very close to the
roadway.
Mr. CoNsTANDY. lf that pipe had been extended_.,
could not the
slope have been brought back fa.rther and that haza.rd been removedf
Mr. PrusK. It could ha.ve been; yes, sir.
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Here we are in Missouri, with a drop inlet in the median, ag&in
raised above the surrounding terrain, level of the terrain. This would
constitute quite a hazard if hit.
Here, also in Missouri, is drnina.ge carrying through a grade separa
tion structure, a. very common type of drain inlet. There is a vertical
surface there perhaps 8 inches high to hit.
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This is a cross drain, again you have a headwa.ll condition, and
wing walls there, particularly the headwall. You can well imagine
thisbeing cut off more nearly to the ground surfa:ce.
Mr. CoNsTANDY. I spoke to a h1ghway pat.rolman in that State.
He told me of an experience he had had with exactly that type of
drain. He was pursumg a car and was pushed off the road, struck
this type of structure, and his car was thrown sorne 15 to 16 feet in
the air and struck a utility pole; it broke his back, caused very severe
dama.ge to the car.
Mr. PRisK. This is entirely needless and unnecessary concrete.
Here is a side drain which for a car out of control would present
quite a hazard because there is an adrupt rise here, with concrete wall
facing. This is not very well guarded against vehicles out of control.

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Moving now to Rhode Island, we find in the median this sort of a
drop inlet with a circular grate, paved areas around it, which seems t.o
be functioning very well.
This is entirely safe, this type of drop inlet, here shown at the curb.
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When we come out toward the rural section of this Rhode Island
portion, we findthis shaped wall, wing wa,ll to handle the culvert
which crosses the roadway at this point, which in fact does present
a considerable hazard unless the grating is very carefully handled
around that point. It looks to me Jike it is going- to end up too higb
even so, particularly out in this area here. [Indicatmg.]
Here is the type of median drain, and an obstruction at the same
time, seen on the Georgia project. This is going through a grade sep
aration structure. And although the headwall has been cut off, there
still does remain here a less than desirable facility for drainage, from
the safety standpoint.
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This is another type of inlet on that Georgia project where there
is a vertical rise here, very obviously three or four bricks high, a table
top type of median inlet raised above the surface.
This is a parallel drain under the ramp roadway, and ngain with an
�xposed end of the type that is seen perhaps more frequently than
1s necessary.
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In Utah, on lntersta.te 80
¡
we found drnins of this type, and thi'I
curb that we saw yesterday, think does tend to control the drainage.
With these drop inlets tha.t project seems to be quite well served.
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The median drainage is handled in a concrete paved ditch of this
sort. Aside from the fad tlús has a rather sharp V at the bottom, I
think it might be regarded as satisfactory.
A rounded bottom would probably be more sa.fe, functionally.
At the side there is a sharper V ditch with a steep back slope, and as
you can see, the erosion from this s101,>e is beginning to fill up this
particular draina.ge feature and certamly, from the standpomt of
a car running into this type of a break in the slope, this is undesirable.
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Mr. CoNSTANDY. Mr. Prisk, in tl}at situation would benching permit
a flatter back slopeat not a great cost i
Mr. PRIBK. It is possible, depending upon the material, Mr. Con
standy. This slope could have been benched with tho right-of-way
available onthat project and handled in a better manner.
The principal difficulty here is with .the sharp break at the bottom of
the paved ditch and the steep back slope.
Here is the Indiana project, again showing a drain almost completely
flush. Beyond it, however, is an undesirable feature of this medi
dam that we too often find on Interstate projects; the grate itself is
quite harmless.
Also in Indiana we found pipes used under the roadway to dra.in the
adjoining land and to handle natural water courses µi the area. These
are ra.ther large pipes, and as you will see here, they are ]eft open with
out any guard as far ns approaching traffic is ooncemed.
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When you come to a ma.jor junction where there is a draina.ge along
the highway as well as th1s cross dra.inage, very large pipes, sorne of
them running up to 6 to 8 feet india.meter, a.re brought together in this
la.rgedrainage smk to ha.ndle surges in the wn.terflow.
This gives you a.n idea of the India.na. project in terms of the a.mount
of water tha.t does, in fact, drain from a.djoining la.nd and collect
a.long the¡roject. You see ca.rs in the upper right-hand comer of the
picture. I they went out of control on this slope I expect the water
itself could be a very serious haza.rd as far as the mobility of the
vehicle is concerned and also in the event of an overturn.
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More of this same water condition. The water, I think, must be re
garded as a hazard itself. The slopes here are good.
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And here is an interesting dra.inage condition, also found on that
project, where there is a ditch pa.ved down the slope which, of course,
1s not unnatural, but up at the top there is a drop inlet at the sa.me
point, which [slide] going back to the previous slide for a moment, the
outlet is a.t this pomt Lslide] so you ha.ve two places for water
to go immediately in front of that automobile.
Very flat terr:itory. This is also on the Indiana project, showing how
they carry their drainage through the embankment behind the side
piers. This is rather typical of many jobs that we were touring.
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Mr. ÜONBTANDY. Also undesirable, that headwall l
Mr. PlusK. lt presenta a very, very solid hazard.
Mr. CoNSTANDY. Could we quickly go through the panel members
and have your thoughts on the drainage1 Mr. Wilson 1
Mr. WILSON. To start out here, I thmk that we saw sorne fairly
good things in sorne areas. The flush-top drop inlets that we saw in the
earlier medians there were very good. In fact, the media.ns in gen
eral were good, I think-but it is very easy to destroy their quality
bylutting sorne hazard up in them.
nd I saw later on, in sorne of the.se slid� that is exactly what
happened.
Before we are too critica} about the type of drop inlets, I think
it should be pointed out here that snow and ice create such condi
tions, in sorne parts of this country, that possible a flat drop inlet
would not handle them all properly. I am not a drainage expert; I
just bring this up to your attention.
Mr. CoNSTANDY. I think it is worth mentioning. Is it also not true,
in that type of situation, that sorne other design might accommodate
that problem, yet at the same time not present thehazard1
Mr. Wn.soN. That is quite possible,yes, sir.
I would like to point out that quite often deep ditches a.long the side
of the road can be graded to a higher elevation by merely changing
the style of the drop inlet or the manner of carrying the water on
ward. I would also like to point out that deep ditches along the
highway can often prevent early deterioriation of the pavement by
giving proper drainage.
. So you have to compromise this thingin this a.rea..
Mr. CoNSTANDY. Thank you,Mr. W1lson. Mr. Skeelsi
Mr. S:s:EELS. I agree we have seen sorne excellent exa.mples in here
and sorne that are not so good. It seems to point out that it is possible
to do a pretty fair job on this ítem if it is looked at in the light of
automot1ve safety.
I arn particularly concerned with dams across medians which sorne
times are very abrupt and sharp, and with the parallel drains under
the bridge p1ers along the side. These almost invariably start out
in a vertical wall which better attention should be given to, as these
wouId be very lethal.
Mr. CoNsTANDY. Thank you, Mr. Skecls. Mr. Huff?
Mr. HuFF. I agree that the protruding inlets, tops, crea.te a hazard
to traffic and I agroo with what the gentlernen have JUSt sa.id. However,
we have had sorne expressions from people who are well versed in
drainage. The so-called grate-top inlet is not efficient for carrying
water. lt is particularly bad where you have a lot of trash and things
that. cover it and stop the flow of water.
And I would say further that I believe sorne studies will have to
be made to develop a more efficient inlet and to avoid sorne of the prob
lems of stoppage I justrnentioned.
lfr. CoNSTANDY. Thankyou, Mr. Huff. Mr. ,vilkesl
Mr. 1VILKEA. Many of the examples we saw were quite good. How
ever, it is pretty obnous there are sorne details that were not executed
very well.
As Mr. Huff has mentioned, this grated inlet does tend to becorne
clogged with trash. There have been inlets developed, though, that
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provide both the grated inlet and slot that will be self-clea.ni.ng. And
we ha.ve attempted to distribute sorne of these deta.ils to the Sta.tes.
We hope that they will beadopted.
Other details we saw were the result, I am sure, or a designer
attempting to produce a maximum economy. For exa.mple, the end
wa.ll tha.t spilled down into the ditch could be elimina.ted complet.ely
by a. longer bridge. So this designer, in developing what he thought
was the most economica.l design, encroa.ched into this ditch area. w1th
his embankment and, as a result, it produced a second a.rea. haza.rd.
I guess that is the point I am trying to ma.ke1 tha.t if we a.re willing
to spend more money, many of these details coul<1 be corrected.
Mr. CoNSTANDY. Yes. We aga.in are looking at situa.tions where per
ha.ps there were coru;iderations of first cost a.nd perhaps they were
not really concerned with economics.
Mr. Rickerf
Mr. .lUCKER. Two points: One, it is certa.inly objectionable to run a
la.rge culvert out beyond the ditch line where it makes a hazard in
itself. On the other hand, if it is cut back flush with the side slope,
it is still a. hazard, because there is a large hole there that vehicles
could drop into. I don't know that we can get awa.y from that hazard
and maybe we need to evaluate which is worse, to ha.ve a. round pipe
ora hole.
The other point, I am not sure I entirely a�ree as to the hazard
involved in a modera.te amount of wa.ter in a ditch. Certa.inly if the
water is deep enough to cover a vehicle, it would be a hazard, but-
Mr. CoNSTANDY. I a.m sorry-deep enough to what 1
Mr. RxcK.ER. To conta.in a vehicle. If it went under the water it
would be a hazard. But it could be that a. relatively shallow body of
water there would be a very etfective deceleration device in itself. And
there are many, many parts of the country where there will be water
standing in the ditches a large part of the yea.r.
Mr. CoNSTANDY. Would it be true, too, that the relationship between
the depth of the water and the ratio of slope and height of it should
be considered i A car going over a steep slope is apt to turn over; if
it turns over in the ditch, it would not ha.ve to be deep to kill the
driver. We a.ll on the committee are acutely awa.re of an example of
that very same thing.
Mr. R1cKER. I have never seen crash tests in the movie, vehicles run•
ning into a shallow body of water like this. I am just guessing that it
might be well as a deceleration factor.
Mr. CoNsTANDY. Thank you.
Mr. lIARSHA. May I ask a question i Would an additional guardrail
in the vicinity of these extended drainage pipes, these large cor
ruga.ted pipes, possibly alleviate any of the hazardi
Mr. R1cKER. I believe, Mr. Congressman, as we ha.ve been discuss
ing for the past several <lays, guardrail itself is a hazard and we need
to evaluate whether it would lie less of a hazard than the exposed end
of the pipe or more. In each case, perhaps, it has to be thought of
individually, <lepending upon the curvature of the road.
Mr. HARSHA. Thank you.
Mr. CONSTANDY. Sorne of the examples we saw, incidentally, <lid
ha.ve a guardrail protection for the hazard. I would suggest in each
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case it was not sufficient to prevent the car from getting into the
hazard, particularly the one in Indiana, the larga paved bowl. There
was a section of gua.rdra.il there but it would be fa.1rly easy to go behind
it and end up in the hole. Ba.ck aga.in, if you a.re going to install gua.rd
rail it should be done correctly.
Mr. Prisk, you ha.ve the next section dealing with shoulders. Would
you quickly run through that1
Mr. PrusK. Yes. This is a project in lndiana-the old section tha.t
wa.s looked a.t the se.me time we looked at the new lntersta.te work.
Here the shoulder is cut off by the use of a curb, which moves down
into that entra.nce a.rea to shield the entrance la.ne. This is the old type
design in Indiana.
Here we come a�ain to a considera.tion of shoulders on the Indiana
project that has JUSt been opened a few months. In this case, the
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shoulder goes directly into the acceleration lane. And there are no
shoulders, as you will see, on the ramps. This is an undesirable feature
to omit shoulders from ramps. A shoulder does pick up, as you get to
this point. [Indicating.]
In this rnstance, a very unusual installation of guardrail ;which
is shown here on the Indiana project, you see curbs that control move
ment of the entering traffic and the guardrail is pulled in here so that
this shoulder, which normally starts here [indicating] and would run
on up to the structure on top of the grade, is bisected by the guard
rail installation.
Mr. CoNSTANDY. So half of the shoulder is behind the guardrail Y
Mr. PiusK. That is true.
Here is a view close up so that you can see the shoulder paved out
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to here and the guardrail running down the middle.
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952
Mr. CoNSTANDT. Yes. That lee.ds into'a bridge that does not carry a
shoulder across it. Is that not correct1
Mr. Piusx. That is true.
Now as we move into Nevada, we find this shoulder condition1 which
is very desira.ble from the standpoint of its appea.ra.nce a.nd for delinea
tion purposes. These are the travel Janes, the black la.nes; the shiny
surface out here is the shoulder surface. From that standpoint, it does
provide a good aid for traffic.
This is the same condition under poor weather conditions during a
snowstorm. Again, along here you have this asphalt curb for drnina.ge
control.
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This picture is one on the Missouri project showing the shoulder, first
paved 2 feet wide with an asphalt mat, then 8 more feet of treated
material, and sorne slight oiling of the rounded surface. The.se slopes,
as you see, are rather substant1al as you move on down here. [Indi
catmg.]
Thls is the type shoulder that they have. Not any too stable. We
understa.nd sorne additional work is to be done on this shoulder, and
certainly is needed, because it is soft now, easily pressed in just walk
ing on the shoulder.
Another view of this same shoulder on the median side, showing
perhaps a. little bit more transverse slope than is desirable. A shoulder
should have a relatively light slope from the edge of the pavement
over to this point. [Indicating.]

954
Here is the Oklahoma City project, which has the feature that we
saw in Indiana, no shoulders on the ramp at all, both sides curbed. Of
course, this is an urban section, perhaps a little more reason for that
condition being found here. But we do have the shoulder through this
area [indicating] which is cut off at this point, grass, and, in fact, the
light pole is installed at that place.
And here you pick up the shoulder again as you move on through
the job.
It is a matter of discontinuity of the shoulder. I think it is certainly
undesirable. Motorists should alwa_:rs have a moving travel Jane with
a shoulder alongside, wherever poss1ble.
This is another example of how the shoulder gets cut off, and th&t,
of course, shields the entra.nce movement, but at the same time it does
make for an obstruction in the shoulder.
, (Atthis point,Mr.McCarthy assumed the chair.)

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Mr. Piusx. Here is a closeup of that obstruction. As you move up
and over all of the intersecting streets, this is curbed at this point.
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Now on brandnew work, just outside Oklahoma City and off the sub
ject project, we find this is still going on, that the shoulder is discon·
tinued at this point, the curb is introduced directly in line with the
shoulder, in order to permit this entrance ra.mp.
This, of course, saves a little bit on your design out in this area as
far as space requirements are concerned. But it does not position
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through traffi.c too well. 1
Here is Rhode Island Interstate 95, where your shoulder actuany
is employed, ali of a sudden here, for a deceleration lane. And so you • 1
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lose the shoulder at that place. And here aga.in is a discontinuad
shoulder. People are apt to break down at almost any point on the
moving le.ne. lt is un
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redictable.
Here is the kind o condition we he.ve in Ohio on one of the entrance
rampa where, with weather conditions, this soil is rutted out very bad-
ly. And this is not a traversable shoulder. This is a ramp, of course,
here [indicating].
In Utah, you have somewhat the same condition that we saw in
Oklahoma City. This is Salt Lake City here, and here is the shoulder
interrupted again at that point.
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Here is a condition, also on that same Utah project, where shoulders
on the ramps are carried on down through the ramp. The ramp aline
ment, as we pointed out in yesterday's d1scussion, is very good at this
point. But the shoulder cutoff, as I showed you a minute ago, is also
evident here.
Here, too, is a similar condition which shows how the guardrail gets
warped at this point
h
even though we have a shoulder provided on the
bridge. There is no s oulder commensurate in width provided back in
this area. [Indicating.]
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Proceeding north on 1-15, with Salt I.ake City to our right, you
have a. choice of turning off here to go into Salt I.ake City on lnter
sta.te 80 or continuing north toward Ogden, Utah, on Interstate 16.
This, in fact, is the shoulder [indicating] of this approach roadway
that we have been on. You will see cars that move on right up through
this, what appears to be the shoulder area.
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Here is a view of this same place, and this is this shoulder condition.
And if you will just watch the red car as he moves from this place
(slide) as he comes ahead, he progresses here (slide) and through here.
Mr. CoNSTANDY. Of course, it is the one next to him we were con
cerned with, but the red one is easy to see. The car riding the shoulder,
restricted shoulder, going over thebridge.
Mr. PrusK. Here the car is really induced into the shoulder beca.use
of this condition.
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Going on ahead, here another one comes up on that shoulder in the
same fashion as the first shot we saw. Watch his progress.
He comes on up the shoulder. You see what happens to the shoulder
here. It narrows down at the structure and if he were to continue on
the shoulder, he would find himelf in sorne trouble.
As you go immediately under the structure where those pictures
were taken, this is the condition that you run into: curb gore at this
point not too traversable down through here. [Indicating.] That is the
off-ramp and this is 1-15 straight north. That concludes this series.
Mr. CoNSTANDY. Let me ask the members of the panel their
observations. Mr. Wilson i
Mr. Wn,soN. I would like to make about three points here in con
nection with shoulders.
If there is any place where vehicles need maneuvering room-1
it is in
the vicinity of exit or the vicinity of entrance to limitecl access
facility.
There is sometimes a great deal of hesitancy taking place on the part
of drivers, not knowing exactly what to do or where to go; and you
see sorne strange maneuvers take place, which is all the more reason
why, not only should you give them a ful) shoulder, but you should
give them every other available chance to get off the road if they do
reach an emergency as well.
I would like to agree with Mr. Prisk on the desirnbility of using
contrast treatment between shoulders and main line trnffic Janes, par
ticularly where you can use a concrete pavement with a black asphalt
shoulder.
However, this can be accomplished in other ways as well by use of
open graded mixes which lrnve a different surface texture, and you
can also use asphalt. It can also be done by using edge lines; and as I
mentioned yesterday, it is desirable to carry th1s contrast treatment
across structures, where the structure may be all white surface.
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The shoulder itself mny require sorne kind of black treatment.
I think it is importnnt, in my own opinion, that shoulders should be
paved. lf you look at the skidding-type nccidents the skids start on
the travelway mnny times nnd nre carried right off in the shoulder a.rea.
Whenever you get into n soft mnterinl, there is alwnys a chance that
the vehicle mny over1um by getting cnught in the soft material.
I think we hnxe pnved our slioulders, nn<l particularly the right-hand
fhoulders, in Cnhfornia for ns long as I cnn remember. We have
recently de<'ided to pave our inside shoul<lers from n 2-foot width to
a full 5-foot width on our freewavs.
This will result in a slightly higher cost initially, but will certainly
reduce maintenance overall.
Mr. CoNSTANDY. Thank you, lfr. Wilson. Mr. Skeels 1
Mr. SKEELB. Not being an expert in this nrea, I will mnke one point.
It was not shown in Mr. Prisk's slides. This is the problem of the
shoulder on the cloverlenf rnmp.
Many of these cloverlenf ramps for various reasons are in restricted
areas and have fairly short rndius turns; and my observation is that
the shoulders nre paved on the inside ancl sometimes the outside of these
tums, and that is where the traffic rides.
I wonder if there is a better solution to this f
The only one I know of is to eliminate the short rndius turns, and
this is not always practical.
Mr. CoNSTANDY. Thank you, Mr. Skeels. Mr. Huffi
Mr. HuFF. I believe there is no need to comment on what Mr. Prisk
said. I was more impressed by what he did not say than I was by what
he did say.
He did not discuss the adequacy of the width of the shoulder as
related to the needs of trnffic. Nor did he dwell very much on the tur
bulence crented when a shoulder has to funnel into a narrow bridge.
Emphasis in discussion of shoulders should be
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ut upon the question:
How wide should a shoulder be on the road an how wide should it be
on the bridge as related to the road 1
In my opinion the bridge shoulders must be 2 to 4 feet wider than
the road shoulder, and it is my personal opinion that road shoulders
should be at lenst 12 feet wide irn,iead of 10 as is now provided for in
the standards.
Mr. CoNST.NDY. Would you suggest that on both sides, Mr. HufH
Mr. HUFF. Definitely on both sides. Originally the shoulder on the
right side was provided for cars that got out of control ,and had to go
over and stop. The shoulder on the left side was an obstruction clear
ance only. With increased speed of automobiles and increased number
of automobiles, it is my opinion that the clearance-the obstruction
dearance for the raíl should be wide enough to provide for a stopped
vehicle as well as for clearance.
Mr. CoNSTANDY. Thank you, Mr. Huff'. Mr. Prisk?
Mr. PR1sK. I would like to sny that I am impressed by what Mr. Huff'
says a.bout the provisions for shoul<ler width. I thmk this is very
definitely a move toward safer design, particularly on structures. And
I would fully concur in the comments that he has made.
Mr. CoNSTANDY. Thank you. I would like to say that Mr. Prisk's
omission of those is prohably my fault brought about by an effort to try
tohurry this along so we can conelude it today. lJr. Wilkesi
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Mr. Wn.K.ES. The early highway research showed that if you provide
a side clearance of 6 feet :you would not reduce the capacity of the main
Janes. I expect that this 1s the source of many of our practices today,
and we have not sufficient clearnnces for the out-of-control vehicle.
We f&il to really appreciate the volume and magnitude �f the haz
e.rd-of the frequency of this type accident.
Mr. CoNSTANDY. You suggest along with Mr. Huff that this is an
area which should be looked into? The adequacy of the present
standard?
Mr. Wrr,K.Es. Yes.
Mr. CoNSTANDY. Mr. Ricker?
lIr. ,vu,Kt:s. Let me make one more comment. The photo!rraphs
we saw of the Utah project illustrate the use of this shoulder as a
rccovery aren where the ,·chicles were either undcC'ided or dc>libemtely
rode through this.
They saw they had a clear Jane and did not merge into the left as
perhaps the pre,·iotts signs had instl'llC'te<l. So this did proddc some
mensure of safety to these ,·ehicl('s through indecision or deliberate
effort on their own. And I think that that is an important element in
the design of the gore of the highways.
Mr. CoNSTANDY, Thank you, Mr. Wilkes. Mr. Ricker?
lIr. R1cKm. Coul<l we be going baek to the first picture of Utah
showing the sho11l<ler problem there while I am discussing other
thingsi
The matter of closing off the shoulder at an entrance ramp has been
controversia] for many years, and we <liscnssed this a number of places.
The Illinois tollway people tol1l us that they had no e°
id('nce of
problems because of that design, although it existed on ali of their
entrance ramps. So the opinion is not clear.
On the other hand, when wc look at the reason why we have should
ers on this type of highway-a vehiclc breaks <lown; the driver needs
to get to a refuge point. immc><liately, an<l if there is a long stretch such
as t.his where he cannot get. off on the shoulder, he cannot get to his
refuge. And when he is rt>ady to start up a¡rain, he needs an unob
structed path to speed up on thc sho11lder and get back to the travel
Janes.
I nm looking for the first picture of your last series. This is a ,·ery
dramatic picture showing what happens when you pave the main
roadway with the same material as the shoul<ler. Someone has tried
to change the impression that that is the main roadway, to make ita
gore ora shoulder; Lut the pavement itself clearly tells you that if you
are going straight alwa<l, you follow the straight-alwad path and do
not pay attention to the paint lines.
This happens in other areas as well, where joints in concrete pave
ment do not match up with the intended Jane alinement and the paint
lines cannot. be strong enough to onrc-ome them.
I think the answcr woulcf be to c-hange the texture of that shoulder
pa,·ement so that. it is clearly a different. use.
lfr. CoNSTASOY. Thank you, llr. Ricker. The last ell'ment we have
to <liscuss is slopes.
lIr. PmsK. "'e hani a few pictures of slopes on each one of the proj
ects that I am going to rttn through rather quickly.
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965
This subject I t'hink has been apprecia.ted by the panel and by the
committee as they have looked at other features of design. This simply
illustrates the various types of slopes in common use, 4 feet vertical
it is what we refer to as the 4-to-1 slope.
This is a view of the Ohio project, on the Ohio Interstate 80, very
wide median, flat slopes, as you see throughout.
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The median is mounded up in the center. Drainage carried on each
side of each roadway.
Here again slopes are flat. You have the advantage of turning cars
away from the center median pier with the slope condition of this
sort.
Here is a closeup, closer to that median pier.
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967
Slopes of -this type are relatively stable and easy to maintain m
contrast to the steeperslopes.
Here is l:!he other side of this same center pier again.
� -TI" -
�
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Off to the side you have nicely sloping roadside to backslope, made
up ·here about 4 to 1, which can be traversed by a vehicle safely.
This is the median condition at this point.
Mr. CoNSTANDY. This is on the other design section. There is an
obvious difference between two pa.rts of the section that we looked at;
one project had this ty.Pe of swale and the other one had the berro.
Mr. Prusx. 'I'hat is r1ght. This is depressed median and also some
wha,t narrow.
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And this continuation is on the same section. Side slopes are also a
little steeper.
Now we move to Missouri, and we run into high fills of this type.
There is no guardrail put in on this project at all yet, and I think
you can see that easing the slope in this kind of country is a rather
substantial job, but at the same time it presents a substantial hazard
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Here there is a drain�e facility down at the bottom.
Moving along on the project, this is rather flat country, and slopes
are easy to control under these conditions.
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971
A SJ?(:Cial situation, of course, introduces itself if you find rock
alongs1de, and in the severe cases here this has been cut back to 20
or 25 feet from the pavement edge, still stands there, somewhat
of a hazard.
This on the Indiana projects shows relatively good slopes to
the roadside, carrying on out all the way to the right-of-way line.
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972
On the Nevada projeot there are differences in grades, as you will
remember, between the two roadways, very high slopes here totally un
protected for the most part and probably standing about l½ or 2 to l.
Here is a view of a truok negotiating one of those slopes.
And here again you can see the difference in elevation, natural sur
roundings, and the roadway, types of slopes that are employed at
this point.

973
1· Still another view of the countryside there in Nevada.
1
Under poor weat:her conditions, again this is the kind of slopes down
through the median to the other roadway.
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And here, as you enter a rock seclion, you get into a more severe,
much more severe slope, and to a degree much more severe hazard.
In Gilorgia you find this kind of condition. The median has a good
many trees standing, and the slopes move out to this point, with
the median being mounted up where the trees are located.
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975
On the roadside slopes are moderately good, but you find conditions
of this sort where water is dammed up.
And you have, although with a fairly good slope here, quite a pond
at the bottom. When these are wet1 without being properly covered
with vegetation, this becomes very hazardous to negotiate.
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Occasionally on projeots of .this sort, as we did here in Georgia, we
find mounds of dirt tha.t are left in areas where it could so well, with a
little bit of attention, be moved to adjoining sections to ease slope.s.
Slopes themselves right in this area were probably about 2 to 1 or so.
Nearby sources of material and modern earthmoving equipment
make it possible to distribute soil in such a way as to make slopes ne
gotiable. Sorne of thatsort of thing was done here.

977
Going through to Utah, one of these gores that you looked at, it
would be a good place to have sorne extra dirt down m here, and these
slopes being-if they were a littJle bit flatter, this guardrail could well
have been eliminated, and this would be a negotiable a.rea.
Here is one that is in fact negotiable. We have all seen pictures of
this previously.
Here are the slopes in the median. Again these slopes must be more
abrupt, if the medmm is not paved. A portion of this project does have
a paved median, and the other part is unpaved. And steeper slopes of
course are on the unpaved sootion.
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This is still another view of that side slope condition that we were
looking at a moment ago.
Slopes here are such that if the dirt were readily available, right-of
way is setting back in here, and this could have been perhaps eased off
to the advantage of anyone that might move on that side slope condi
tion.
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Next we oome to Montana. This is one of the things that does hap
pen under certain drainage condition. You gradually cut a ditch deeper
and deeper into the roadside, so that it too becomes a ha.zard. And un
less this ditch is properly controHed, sometimes lined, it will be very
clifficult to negotiate with a vehicle.
I am not quite sure why we have that. This is a man taking sorne of
his porkers home, a nice flat slope.
Mr. CoNsTANDY. We thought it was an antifreewa.y demonstration.
Mr. PRISK. I gu�
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This is in Rhode ls]and. Your slopes, of course, are very easy here.
They are fairly flat. The trees are the hazard. [Slide.] Here you have
rocks coming through the surface of the earth-this happens in New
Eng]and-as we11 as the trees. [Slide.] And more of the sa.me.
Here we have trees very recently planted and rather too close to the
pavement, if I might say so.
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Here there is rock adjoining the roadside, and these slopes really
ought to have sorne protection. It is hard to imagine how this cango on
without ultimately proving:to be a hazard. [Slide.] Here too is more of
the same rock. [Slide.] Still more. [Slide.] And still more. There was
an accident in this general vicinity.
And here is a case where they cut the rock back in a slope plane,
which leaves the rock with a relatively smooth surface as against the
naturalrock that we find in other places.
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This is sorne landsca.ping that was done on the project, just north of
Providence, on 1-95. A great <leal of money and effort went into design
and construction of attractive roadside at this point.
How much attention is given rto slopes, I do not know. Considerable
to vegetation.
Mr. CoNsTANDY. We would like a short comment from each member
of the panel on these slides pertaining to slopes. Mr. Wilsoni
Mr. WILSON. Here again I think we saw sorne evidence that we are
trying to give the motorista little bit of relief if he <loes have to leave
the road. Ido not think anyone could dispute the fact that we ought to
have wider slopes and flatter slopes.
Particularly I was pleased to see sorne widened areas cut. Sometimes
this is rather costly. Grading is a pretty costly part of the road projec
t.
There is a:lso another advantage here in that it helps during your
snow removal operations. And I think we have to look at slopes of all
kinds as a matter of economics.
The cost is not only involved in the grading of the slopes and the
grading could be very costly. I notice in one of these areas, the ground
was rather flat; and I imagine rthat the material would have to be
hauled in considerable distances.
Not only tha:t, you would have to huy additional right-of-way and
it would have to be a part of •the very early design or the very early
planning stages of a job. That is the time when you have to lay down
your lim1tations on slopes.
Mr. CoNSTANDY. Thank you, Mr. Wilson. Mr. Skeels i
Mr. SKEELS. Well, I agree that flat slopes are goocl. However, the
s)ope itself, the actual grade of the slope, is not so bad providing it
<loes not get extreme. By extreme I am thinking of greater thnn 4 to l.
The hazard is really-it really comes about at the bottom of the
slope or toward the slope. Visualize a car going out of control, going
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down this slope. He can negotiate a pretty steep hill. However, if he
<'ornes to the bottom and rW1s into a V-d1tch or bunch of trees or a
sharp back slope or rocks, that is where he rea.lJy gets into his trouble.
In the rock cuts, these prob&bly should be protected. One way might
be to face thern with a fairly low concrete wall that would at least
make it smooth. It is pretty hard to make it soft, but you can make
it smooth.
I have mentioned ditch bottoms. They should not be allowed to be
V-shaped. They should be gr11d11aHy rounded so thnt a car going
through it will pll.'B through and not be brought to an abrupt stop
against or toward the back slope. Obviously, trees should not be toler
ated close to the roa<lside. Trees should not be planted on the slope it
self, as we saw them on t.he pictures.
One other itern on the slope. In sorne cases the slope can be flattened
and carried out farther frorn the road to J.>rotect an underdrain. In
other words, if an underdrain is extended, 1t becomes less hazardous,
&nd the slope can be flattened to oover it up. Carry it back a hWldred
feet frorn the road, and flatten your slope to cover it up, and you do
not have to worry about the head wall or the end of the pipe.
Mr. C'oNSTANDY. Mr. HufH
Mr. Huw. Of course the advantage of the flat slopes has been dem
onstra.ted over and over. We might say that this was first brought
strongly to our attention a good many years ago by one of the auto
mobife rnanufacturers whose representative is s1ttin� to my right. We
should be grateful for the groundwork and the bas1s upon wh1ch this
important feature was developed.
I might add that on the Interstate Systern it is entirely possible that
we would have enough right-of-way to develop flatter slopes than on
most of the roads that we ha.ve already built. However, highways
where right-of-way has been a problem will constitute one of the
gres.test difficulties in developing flat slopes on already constnicted
highways.
In my opinion it is most important that we do rnove to developing
slopes in the area of 6 to 1, wh1ch is reeommencled by the yellow book,
on all new highways and on those which have already been built where
it is possible.
Mr. CoNSTANDY. Thankyou, Mr. Huff. Mr. Wilkesi
Mr. Wn,�. I do not helieve I have any comments to add to those
that ha.ve been made previously.
Mr. CoNSTANDY. It is a lit.tle out of your field. Mr. Ricked
Mr. R1CKF.R. I do not know that I have much to add, except that in
many parts of the country such as in Pennsylvania we have almost
contmuous cuts and fills as we traverse the hilly 1111d mountainous
areas; and it is literally not possible to get the flat slopes that might
be de,sirable, the same way with the rock cuts that are exposed.
There is another lll'('a here which is prohahly not for discus.<;ion to
day, but the variation in scenery that is obtained bv having rockcnts
or changes in topography may resnlt. in drivffs heÍng more alC'rt. and
staying awake lon�er; nnd I do not lmow that we have nny data yet.
which shows th:it they can drive these roads snfer, bnt I suggest there
is a _possibility.
Mr. CoNSTANDY. Thank you, Mr. Ricker. lIr. Chairman, thnt con
eludes the presentntion of the slides on the nine projects. It hnd been
my intention at this point to ask Mr. Prisk to make sorne summary
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986
observations. I think with the time we have remaining that I will ask
lea.ve that Mr. Prisk might P.repare that statement and submit it at
t.his point in the record as exh1bit No. 8.
Mr. McCA.llTHY. Without objection, it is so ordered.
(The document referred to follows:)
SU.IUUJlT STATEMENT or ÜB.A.llLEB w. PmeK, CoNBULTANT TO TBE 8PlllCIAL SUB·
COMMITTEE ON THE FEDERAL-AID ÜIGHWAY PBooB.AM
INTRODUCTION
The newest Interstate blgbway projects in nine States were in.speeted durlng
the period trom Aprll 3 to May 2. 1967 tor the adeqnaey ot thelr deslgn tor satety.
These lmprovements appeared to represent impartlnlly tbe freeway design just
uow bt>ing o¡H.'ned tor ¡>Ublie travel on the Interstllte bigbway system. Eneh se<:
tion was loeated in a dlfferent geograpbk reglon ot the United States, eorre
sponding wlth the reglone of the Federal Highway Administratlon. In tour States
the projects were entirely rural, In two States entlrely urban, and in three State1
a mixture ot urban and rural.
Rondside hazards were given S(>e('lal attention during the fteld revlew ami a
surprlslng number ot these were observed on ali nine projects. Because the proj
ects visited are typleal, it is not umeasonable to inter that many ot the same
weakn�- could and undoubtedly do exist thronghout the 25.000 miles ot the
Interstate Rystt•m that are uow In use.
The prerequisite to lmprovement ot thls situation is a tborougb understand
lng ot the nature ot the hazards. In my judgment, they arlse not so much from
willful violation of offldnl design staudards for the Interstate Svstem as the
widesprMd. fnilure to recognize nnd treat a major treeway aeeident problem.
The problem involves single vehlcles tbat leave the roadway out of control. a
type of acddent tbnt nceounts tor about three-tourths ot the trafflc dea.ths among
use-rs of the Interstate System.
A parallel and rPlated diffkulty 1<tem11 from the lnsnffldeut and ott-delayed
use ot Jrnowledge eritleal to satety. Mueh of this is readily available trom
reliable experience and researeh resourees. In the nine State review, tbe prlnei
pal design elements related to roadside hn:r.ards were dnssified in the following
cntegories: Guardrall, median barrier, structures, i<honlders. curbs. drainage
fndlities. signs and slgn snpport.�. llghting 11tnnd11rd>1. gores. slopes.
lnformation was &!<l'etnbled on each of the nine projeets tor the items listf"d.
During tbe past tour dnys ot this henrlng, a review ot tbe roadside eondltions
has been presf"nted. My testl.mony has been based on a fteld vlsit to ea<."h project,
conferences wltb many of the affected publlc officinls, and close study ot thr
design policies and praetlces npplicable In eacb case.
Only four projects, those in Oklnbomn, Georgia, Rhode Island and Montana.
hnd rondwny llghtlng lnstallatlons and obvi<msly the observatlons on llghtlng
standnrds relate mninly to tbose States. In Missourl, even though the Inter
"'tate projPet ins¡w(·t!'d hnd b�>en open for about six month11, guardrnil work
wns ineomplete, being In pince nt only a few structures. Hence the comments
on lfü,sourl gnnr<lrnil have applicntion to only n smnll and ¡>t>rhnps nnreprest-nt
atlve sample of whnt Inter wlll be instlllled.
The nine projects ha<I been open to trafflc tor periods ranglng trom three
to eight months. �lore often thnn not. cot1siderublP work wns gPnernllx still nt>t>dP<I
to obt11ln a fncllity as s11fe ns hnd been orgln111ly plnnned. Tbe missing wort
w11s typicnlly clnssed ns "cle11n up." Included were final alteratlons to gnardrail
grading nnd pnving of shoulders, grnding and 9eeding ot medinns and slopes.
dosing of <.'C.>m•trnetion crossovers iu the median, in><tnllntlon of ftnnl signing.
d<>lineation, and mileposts. and n11111Pro11s otlwr fpaturPs dire<>Uy alfectlng the
satety nnd quallty of service available to users ot the Interstate System.
G11ardrail
Be<>nuse gunrdrnil h, the roadwny element moRt commonly struck as vt>hicle11
rnn off the rondway of the lnterstnte Systems, lts design and use are of
1<igniflcnnt importance. Obviously the pnrpose ot the usual guardrall lnstallatlon
is to protect the rond user trom a consequenee more severe than tbnt ot 11triking
the guardrail lt!<elf. lt should be U!<ed only where net•e,-,sary 1dnce lt is ltst-lt a
rondside haznrd. Practlces nmong the nlne States visited vary substantiaU,
in this respect.
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987
Helghts ot goardrall measured varled from 22 lnchee to more than 80 lncbee,
sometimee as moch as this withln a given State. A. growlng appreclation ot
the value ot 6'3" post spaclng ia apreadlng ln ali States vlslted and in thelr
newest work at least, the cloeer spaclng Is being uaed to strengthen guardraU
Meetlons. In only three States, Ml880W'l, Montana and Utah, were guardraU
installntiom1 regularly tound to ha·e washer11 on the bolt heads to prevent
ttwir pnlling thron,:h tht> rnil In the ewnt ot collision. Thellt' simple, lnexpensive
wa11hers, along wlth tbe stitrening sectlons used at lntermedlate poeta, wlll
greatly strengthen beam guardrall lnstallatlons.
Blocklng out ot the g11ardrai is tound to be a standard practlce in only a
tew of the States. On projecta in Georgia and Utah, it was found that guardrall
was blocked out only at the sign lnstallatlons. Other sectiorui had no blocks.
On one proje<'t in :lo11t11n11, the medi1111 harrit-r ¡>011t had adually been notehed
so as to obtaln the miuimum standard lateral clearance between the tace of the
rall and the edge of the pavement.
Gunrdrail ends can be extremely hazardOUB to cars l'llllning off the road and
>'honld ht> hnrit>d in tht• gronnd at tht>ir nppronc-h ¡,nd. Tht'y wert' treuted thls
wuy in three of the nine Statee vislted. In other cases, rall was elther flared back
or installt'd pnrallt'I with the roudway uli,:nment and not burted.
Si{lna
'hPre,·er perm11111>nt 1<igns w1>re installed in the gore areas of the nine Inter
stnte projects. they were, without exception, unrensonably heav-y or massive.
Mounting supports for the standard 5' x 6' EXIT slgn varied all tbe way
from a thrw-i11<'h R!Pt>l ¡>0st for a tP111J>0rary i11st111latio11 to two Rteel I-beams
i<ix inc·hes in depth. OthPr sl¡m i<upports ranged up to multiple twt>lve-lneh I
beams for the larger advance guide slgns. The deslrable breakaway fenture
whic-b has been urged on the State bighway departmenta by the Bureau ot
Public Roads for sign installations, was tound on only one ot the nine projects
11nd in this case, only on relath·ely minor type signs.
Curb1
Barrler curb was used without clear JustiftCfl.tlon at many locations. Frequently
it was placed ln front of a guard rall or a barrier rail wbere it c.-ould adversely
atfeet the pro,,..r J>f'rform1111ee of the ruil strueture. Curb is used often for
dellneatlon purposes to outllne gore areas and other locations where there Is
sometimes no tunctlonal need to control dralnage. A highly com.mendable
design noted on the Utah Interstate project In Salt Lake City wae characterlr.ed
by a curb lo<'ntl'fl ul>0ut two feet behind and parallel to the road edge guardrail.
The entire shoulder was paved to and beyond the tace of tbe guardrail and into
the depressed gutter in front of the curb. Paving of tbe clearance area between
tht> t>dge of the usnble ;¡Jioulder and the tace of the guardrail would appear
to be a very desirable contrtbution to safety.
Bridge,
On the Interstate System hrl<lges. safety walks 12 incbes and otten 18 inches
in width were relatiwly common. The need for more tban a brush curb 4 to 6
inches in width 011 bridge11 comµrlsin¡1; the lntt-rstate System is very qne:<tionable
in my opinion. From a performance standpolnt, the sa.fety walk presente a ver
tidt> i<urfa<"e hnznrd at the entrnnce to tht> bridge ami also <'1111 eause a vehfcle to
strike the bridge railit1g system at a higher elevation than would otberwliae
be the case. A nearly vertical wall with a small fillet section at lts base Is
much to be pmerred over the typical safety walk cross-section found on many
reet-nt projed><.
Th·en thongh the standnrds of tbe American Association of Stnte Hlgbway
Officials have been folh,wed rather closely, tbe shoulder systems on tbese
newf'!<t Interstnte bridgPs on the nlne State projects are largely ln.adequate
for trnfflc nee<ls. Only a few brtdges of :my length carrted the full shoulder
width. In one St11te there was undesirable vartntion In the widtb ot S11ecesslve
similar bridges. Evidently. a design change that took etrect tor brldges deslgned
wlthin the Def)Artment waia not applled to similar bridges on the snme project
whi<-h were lwinl{ de�ignpll by a eon,.ulting enginPerin¡:r tlrm.
Median ami side piers were glven a wide varlety of protectlve shieldlng to
avoid having motortsts contact them. In too many cases there was no protection
w-hntever or only a few section.� ot gnardrall placed In advance ot the pier.
In contrast wit.h the generally i.nadequate sblelding of center and slde piers,
a fairly elaborate treatrnent was common at twin bridges where an Interstate
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988
driver leavlng on the median slde mlgbt otherwlse drop to a roadway below
through the openlng ln the median. 0n most projects studled, long sectlons of
approaeh guardrail were fl'lln>d into the mt>di1111 <'l'lltPr llne or even b1>yond to
divert vehidei< from the openlng betwf'('n the hrldges. Tlw solutlon ot dec:·king the
median area was not frequently practlced. Tbls has the advantage ot ellmlnating
the hnzard just rl'fnred to and also remove11 the addltional hazard posed by
the left Pdge par1111et walls.
Among the States, Rhode Island has concluded that 20 teet ls ahout the
wldest median that C'an be economlC'ally paved between twln brldges. Sorne
Htnt1>:,1 that !111,·e studiec:I this itt>m ht>!il'Vf' that llll'clinn wi,lths UJI to 30 feet
<.im b!' ec:·ouomic·nllr justilit>d for pnving. On the niue Intnstate s('(·tinns inspected.
there were many twln brlclges wlth medlans below ten teet that WE"re not pavf'd
over. The separate structures were often less than 25 feet apart, and ellminating
the two parapet walls on the left sldes of approachlng traffi<' would have saved
their cost. plus that of the extl"nsive length ot gnardrail used on the approa<'hes
to the structurl'S. This <'0ul<l frequently support the Incremental eost of pavlng the
mec:lian aren.
Noteworthy among tbe bridge safety deslgn problf.'ms that stlll awalt l'Olut:ion
Is tbf.' devf'lopment of a satlsfactory transltlon fltru<'ttlre between approaeh gnard
rail and bridge ralllng or other elements of a grade i<epnrntlon stn1eture. In two
8tute!'I, Oklahorua and Utah, l<Ome attempt v.-ns ruade to obtain nn anC'hornge but
the design wns not nltogf>ther SU<'<'essful. In the other seven State", there wa" no
phyi;;lcal connec:·tion or evidence ot any nttl'mpt to mnke the approneh guardrail
Integral with the bridge raillng, a pier, or any other i<truetural component. Tbe
nf'f>d for 11n nnswer to this tr11nsition problPm ranks ai< high ns any on the list
ot immedlnte S11fety priorltlf>s. Dlscusslon" and lnformatlon obtnlned durlng the
survey indi<'ated that most Stntes plan sorne t'l'medy of thls deflciPncy. It ·as
lnteresting to notlce the varylng nature of the <'0ncern. In one State, there was
11lmol'lt no gunrdrnll on tbe npproach to i;;tructut'l's, whel'l'llf< in another, the ap
proach gunrdrnil hnd been built to a bridge location even before the bridge deck
hnd been completed.
Bridge Railing
The effectiveness of ralls on bridge stru<'tures Is l'l'lated to their helght as well
as to thelr design composition. Mensurements were taken on many of the f<truc
turPs observed In the nine l-ltatt's. Brid¡w ruil height. 11djoinlng and mensured
froru the rondway surfnce, was 118 low ai< 27 inches in sorne c11ses and as high as
44 lnches In other cnses. The mO!<t common ht>ight of bridge rail wn" 40 inches
11bove the roadway surf11ee. Only a tew ot the States hnd lower or higher bridge
rnlling than 40 loches, whieh suggests thnt this dimension, as well as the tune·
tlonal dt>sign rf'(Jnlrements of bridge ruiling, n(•t>ds to be studied and s¡,ec:•ified
more exactly for 1111pli<'11tion to bridges of the Intrrstntt> System.
Aluminum w11s a common 11ltemnte for steel for bridge rnillng. '.lany ditfPn>nt
configurations were noted. Combinutions with vnrious hf'lghts of conc·rete brl<l,re
pnrn)ll'ts mnke thls element extrrmt>ly eluslve for ernluntion. Rrldgf> de:-igners
11p¡X'11r to exeITisP a grPnt deal of lndh·illunl expression in developing the con·
figurntion of bridge r11ils. A!'i<thetics 1111d the desire to h11,·e a bridge r111l that
you c11n "!14'1' throngh'' i<hould not excet•d thr coneern for a rniling thnt Is nble
to wlthstnnd the lmpnet of a colliding vehicle without fuilure and unnecessary
hnznrd to higbway user!'I.
Shouldcrs
Sorne atb>ntlon was given durlng the 8tltdy to the use of flhoulders on the
mnln rondway and on ramps. In Utnh 1111d in Okl11ho11111, the normal width of
the shoulder wus ft"('f¡uently obstructed by curbs ¡>luced at the entrance ramp
terminal.
In additlon to obstn1ctioni< of the mnin rondwny shonl<lrrs, whiPh should in ali
cnsf>s be 11vai111ble for disahlf>d vehiclef<. a greut inC'onsistPm•y exlst1><l In the deslgn
ot shoulders for rarup rondwnys. In II fpw cnst>s it was diflkult to tell whether tbe
rnmp sbouldPr wns paved. On one projeet the rnmp hnd a pn�·ed shonlder six
ff>et wide on the rigbt 1111d no shoull!Pr pavlng on the Jpft. In st1II another State,
the shoulder of the rnmp ""ª" paved thn•e fpet wide both right and left. El!IE'
where, the ramps were outlined with curhi<. The prnc-tice of paving i;houlders
on connecting rumps at lnterchnngPs obviously has not bf'('11 f<Uffieiently deter
mlned, and U1ere li< doubt thnt. the need for adPquate i;houlders at ali locations
has yet been fully npprecinted.
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8�
Flattenlng alde alopea and roundlng dltcb bott.oma to lncreaae tbe aatety ot tbe
road&lde waa not cbaracterlstlc ot m08t ot the nlne proJecta vlalted. Nnmeroue
Bltuatlone were noted wbere, at least In locallzed areaa, readll7 avallable embank
ment material could bave been nsed to flatten alopes to 6 :1, a alope tbat can be
eately traven,ed b7 a conventlonal veblcle. Becauee grad.Lng coetB are becom1nc
a &01Dewbat 1JIDaller part ot tbe total proJect C08t, mncb more attentfon sbould
be devoted to examlnlng Miope adjustments as new projects are conatruct.ed.
Savlngs In guardrall lnstallatlons, malntenance, and posslbl7 dralnage teatnree
tbat otberwlse would be requlred can be cred.lted agalnat dlrt-movlng coets aao
clated wltb flatter alopes.
Li(lhtíPlfl
lt waa prevlonsly observed tbat only tour Statea lnstalled roadway Ugbtlng on
tbe lnteretate proJects vlslted. Ot tbese four States, two naed ateel polea on trana
former or 11ange bues mounted on concrete footlngs no more tban 1¾ to 2 feet otl.
tbe out&lde edge of tbe paved sboulder. In Oklaboma and Rbode Island, tbe
118.Dle lateral locatlon was uBed bnt the lightlng lnatallatlon wae eomewbat leu
basardoDB becanae frangible bases were employed on the expoeed poles. The
aluminum poles used were of a type sbown by experleoce to break away at tbe
ftanged base wlthout cam!lng serious damage to the veblcle or its occupants. Where
roadway lightlng Is employed, concrete footlngs should be kept to tbe ground level
and tbe lateral clearance from the edge of the sboulder or face of cnrb lncreased
above preeently uffed mlnimums. The enthuslasm for maximum Ugbtlng efflciency
and aeetbetica has eometimes resulted in having the poles In target posltiona and
undesirably close to the roadway. Longer mast arme are possible and with more
powerfnl luminaires at hlgher mountlog beights, fewer Ugbtlng standard& are
needed.
Summar, of need.8
In summary of the study of the nlne lnterstate projects selected essentlally
at random tor tbls study, lt can be sald tbat several urgent needs remaln to
be satli;tlt'd lf the InterHtate System is to become as safe as tbe publlc lnteret
requires. Tbe tollowlng statt'mt'nts hlghllght tbt'se requlrements:
I. Declslons on engineering deslgn frequ,ently bave been based on 1trst cost
considerations rather than on a true cost effecth·eness prlndple. Long-range
economic demands 1mgge11t the bigb importance ot chOO!oling lultial deslgns
that will serve trafflc adl'<)uately oYer the full life ot the lmprovement at a
minlmum cost and wlth a maxlmum ot satety. Tbe malntenance and operat
lng requlreme11t11 aSHOClatt'd witb the various alternate degigns are vital
collt determinants that Kbould receive more attentlon durlng tbe declslons
on deslgn.
II. When separate contracts or subcontracts are negotlated for lnstalla
tion ot 11ign:,1, lightlng, g111.rdrall, dralnage facilities, and similar elements,
a maxlmum ot coordlnation 111 needed to insure that these l!("'l"eral ltems and
tbe festures of the principal construction contrlbute in a unlfled way to
the flnally complett'd higbway i111pro·e111ent.
III. Immediate Hlep,,i !!hould l>e takt'n toward a cloMer worklng relatio11-
11blp between bridge and roadwny design engirreers to a<'hieve safer deslgn
condltlom1 tor the roadway entraoce to bridge 11tructnre11. Lil>eral e,·ldence
exl,:1t.<1 that the ,·ertkal eleruent of the tran,.ltion between roadways and
bridges Is one ot the Wt'11ke11t featnres ot preMt"nt roadside de11ign.
IV. Multl-di�•l¡,linary revlew tt'am.«. operating before, durlng and atter
hlghway construl'tion, are an ald to cryi,tallizing tlmely declslons on many
ltems atlectiug the 1mfety of Interstate projeds. Teams ,.bould be c-ompo..ed
ot reprel4t'ntatl'es trom design, ron11tn1etlon, trafflc, malntenance and perha¡>o!
otber dlvi;1ion11 ot the highway dt>partment who"e vlews re"ult in dech•lons
that atre<'t !!llfety teatnres. Supplemt'ntary as..l,otance ot pel"!!Onnt'I from the
Bureau of Pubiic Road,i and other rompont'nt unlts of the Jo't'dernl Hlghway
Ad111lnl11tratlon. and troru t'nforcemt'nt authorlti� ha11 pro,·ed ,·aluable. The
function11 ot the team loglcally :<tart in the earlit'><t plannlng stagt' In the
conslderatlon ot "uch items 8!1 11ign locatio1111, guardrail plaeement, and llght
lng installations. Team,o should al!40 be active during the ronstruction perlod
110 that adju,-1ment!-I then found to be dt>Sirablt' c·an be made. Betore tbe
projec:•t Is o¡,en to traffl(', tbe revlew tenm :-hould examine the final state
of the lruprovement to in,.ure that tbe highway is in tact ready for publlc
87-TGT 0-68---Q
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use. In tbe admlnllltratlve area alM, care ebould be taken to avold premature
openlng ot projecte tbat are not operatJonally Nte tor traffle.
V. Tbe adoptlon ot a satety croM sectlon to provlde 30 teet or more ot
dear area trom the edge ot psvement on lnterstate projects Is one of tbe
more lmportant steps toward greater imfety ou Interstate projectH. Tbls will
requlre not only tbe revb,lon of standard" tor new work but ala,oo tbe &<"
celeratlon ot programs to remove ftxed object hasards imcb as unnece-ry
guardrall, eigns, treee, utlllty poles, boulders and otber similar ltems. Tbe
deslrablllty Is also evldent of adoptlng 6 :1 or ftatter slope!! at tbe road1dde
wbert'ver practlcal, and tbe smootblng and removal ot ali imb'4tantial ob
stacles from i!le gore, except for tbe standard EXIT elgn and ll&'bt-welgbt
dellneator poets. In all caees, tbe EXIT sigo sbould be on breakawa:, tnie
81lpports.
VI. Wbere basardons obJects are not teaFlble ot removal, lnlltallatlon of
approprlate barrier devlces sbould be ronmdered. Under sucb rondltlonti.
barriere usually sbould be lruotalled at a maxlmnm dlstance from tbe roed
way ratber tban at the conventlonal poeltlon aloog the outer edlt(" of tbe
!!houlder. Speclal lmpsct-attenuating devlces now becomlng anllable 14bould
be emplo� for shleldlng center plers In mediana and for 1tlmllar massh·e
obJects tbat cannot In any reasonable way be relocated or removt'd.
VII. Hundreds of relatlvely mlnor hazards exist in cnrrent deslgns or
In proJects now In use. Tbese should be the f0<.'118 of programs by trafflc
engineerlng and malntenance torces. Corrective work lncludes sucb readilv
adaptable teatures as fran,cible or breakaway basee tor exposed slgn sup
ports and light standards, tbe lo1rerlng at concrete footlnga to ground le-veJ.
tbe removal ot unneeded barrier curb. tbe bnrylng and ftartng ot (tllardrall
approach ends, tbe removal ot 8&fety walks and wlde curbs on bridge struc
tures, and tbe placement ot <'lear understandable signlng 8Ufflciently In ad
vanee ot decision point&
VIII. One of tbe maJor breakdowns noted trom the study ot the nlne ln
terstate projects Is tbe inadequate communlcation and use of avallable re
�arch ftndings and lmproved technlques. Tbe tallure to rommunlcate Is
notlceable at ali levels and actually may be more serlous In the blgber ad
minlstratlve levels than at tbe technlcal level. A cbange ot attitude wblcb
would characterlze the blgbway as a more posltlve contrlbutor to trafflc
A&tety Is a pre-conditlon to progrese In thls area.
IX. Concerted efforts sbould be made to compresa tbe time perlod between
final deslgn declslons and general use ot tbe blgbway lmprovement so tbat
tbe beneftts ot recent advancements In operatlonal practlces, designe and
controle wlll be reallzed In new or remedlal work ou tbe Interstate System.
X. None ot tbe ftndlngs from tbe observatlon of nlne Interstate proJects
can or shonld be regarded as tully concluslve and final. Tbrough properly
dlrected research and addltlonal lnvestlgatlon, more speclftc lntormaUon as
to blgbway deslgn and operatlng deflclencles and solutlons wlll surely be
ldentifted. Nevertheles11, tbe ftndlngs ot thls stndy ot nlne new and represent
atl'e Interstate projects do have high lndknted value. Typlcal ot tbe atten
tlon belng devoted to betterment ot the general sltuatlon Is tbe llstlng ot
Interstate satety lmprovements rontemplated or underway ( See Adden
dum 1).
ADDENDUH l
CURBENT AND CoNTEMPLATED 8AFETY IMPROVEMF,NTS FOB THE NINE lNTEBSTATE
PROJECT8 REVIEWED BY TRE SPECIAL SUBCOMMITTEE ON TRE F'EDERAL·AID
HIOHWAY PROOBAH
Each ot the nlne Interstate projects selected tor revlew In tbe several reglons ot
the Ft>deral Hlghway Adrulnistratlon has been AAid to be deftdent safetywil'I(> In
sorne one or more ot lts englneerlng detalls. Totnl safPty In englneerlng de!!lgn
nnd opl'ratlon wlll never be rea<'l1ed but sorne brlet ml'ntlon ot tbe Jm1tlfied
strl'lng toward that objectl·e onght to be lncluded In the record.
Wlthln the regions and on U..! projects stndled !'ooperntlYely by tbe Subcom
mlttee stnff and a qnnllfled englneer from the Hnreau of Publlc Roads. tbe satety
lmpro'ements Usted below are presently 1111derw11y or contemplatt'd:
Regiot1, Otte-Rhodc 1Rlan4 Inter11tate 95
1. Signe orlglnally placed 2 feet off the edge of shoulder wlll be mo,·ed back to
30 feet wherever 'lewlng conditlons permlt.
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2. JleaT7 alp bridge npportl located In the gore at the Junct!on wlth I-29G
wlll be ellmlnated b7 movlng the elgn bridge to an advance locaUon.
3. Curb and guardrall wlll be ellmlnated trom sores and theee areaa wlll be
paded wlth 8atter alopea.
Relf{o,a Tto0-011.lo lflleralale 808
1. The preeent temporal'f elgnlng on thla project wlll be replaced wlth perma
nent algna of modern deelgn as the next etage ot lmprovement.
R� TAree-Georgfa lfllerltate 15
1. Guardrall on thle proJect wlll be revleed to lncorporate the eatet7 reflne
menta outllned bf reeent reeeareh. Posta wlll be apaced closer to lncreaae
stablllt,. The ende ot the guardrall expoeed to trame wlll be anchored at groond
level.
2. J'ranglble b&aes will be emplo7ed, replaclng the ateel baaee now npportlng
light atandarda wherever theee are In expoeed poaltlona.
3. Trdlc signa wlll be moved b&ek at leaat 30 feet trom the traveled wa,
wberever poaalble.
f. Median lnleta wlll be lmproved so not to be an obatructlon to trame lnad
vertentl,y enterlng the median.
Regw,a Four-IfUliau IttleralGte 69
l. Guardrall revlalona wlll be made to lnclnde tbe anchorage ot approacb enda
at groond level and aborter post apaclng at polnt11 where maxlmnm protectlon la
requlred.
2. Dralnage tacllltltea wlll be made leBB of an obatacle by ellmlnat!on ot
headwalla and with extenslon ot preeent cnlverta.
3. ConBlderatlon la belng glven Jlghtlng reqolrementa at lntercbangee and
other polnta ot need.
Reglott F,«-Mi11011rl lttter,tate �
l. lmprovement11 wlll be made to medlnm draln11 and dltch bloca.
2. Break-away 11lgn11 and light 11upportl wlll be lnetalled.
3. The lnstallatlon of addltlonal guardrall at polnta ot apeclal hasard wlll be
undertaken and guardrall deslgn wlll be lmproved to accord wlth lateet eatet,
standard&
Reglott B�klaAomo lttterltate ,60
1. Improvementa are belng made In the anchorage of guardrall to bridge
atructuree.
2. Improved guardrall designa are to be lnstalled.
ReglOA Severa-Nevada Jnteratate 80
l. Trame Blgns wlll be relocated at a turther diatance away trom the roadway.
Tbey are presently 2 feet beyond the edge of the shoulder.
2. Addltlonal guardrall lnstallatlons wlll be made to protect motorista agalnst
the basard of nmnlng off hlgh embankments and sorne embankment slopes wlll
be 8attened.
Retrlon ElgAI-Montana Jntcr,tate 90
l. Tbe guardrall on thla proJect wlll be blocked out throughout Ita length and
aborter post apaclng wlll be ueed to guard agalnat penetratlon at locatlona of
epeclal basard.
2. lmprovementa In the algnlng wlll lnclude lnstallatlon of breakaway deslgn
aupporta.
Reg'°" Nme-UtaA Intcr,tate 80
l. Some algM wlll be relocated to a poaltlon on overhead brldgee ao as to
ellmlnate the hazard of ground structurea.
2. Breakaway type lrigns wlll be ln11talled throughout the project.
3. Better detdgn wlll be used for the protectlon of motorista wbo strlke the
approach ende of guardrall.
4. The dealgn of Exlt and Entrance ramp termlnals wlll be lmproved to reduce
the ftxed obJect hazards at theae locatlons.
Mr. CoNSTANDY. ,ve have looked at the various rondside elements
in the nine States which we believe to be representative of interstate
projects completed in the latter part of 1966 and the beginning of 1967.
It would be most pertinent at this point if each of the members of the
panel were to evaluate what it is that they have seen.
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I realize that sorne of you have sorne additional comments, which
would be helpful and would enhance the record, but we would be
n.ppreciative if you would give your opinions as an evaluation of what
you ha.ve seen overall on these projects.
Can we begin with you, Mr. Wilson f
Mr. Wrr.soN. Well1 as engineers in this field of endeavor, our rnission
is twofold, as I see 1t.
First we have got to keep the vehicle on the road by providing him
with wider shoulders, wider travel lanes or wider roadwa.ys, delinea
tion mark lines, and things of this na.ture.
The second thing is tha.t we ha.ve got to prepa.re for the inevitable
and that is when the vehicle leaves the highway. We must give the
m"torist a rea.sonable cha.nce to avoid injury and death.
I would like to ca.U this building-in a forgiving quality in the
roadside.
This forgiving quality can take many fonns, ali of which we have
discussed in the past few days. I do not think it will be necessary to
elaborate on the specific · item.s because my remarks regarding thern
are already a ma.tter of record.
However, I am deeply concerned about what I ha.ve seen.
I believe there is knowledge available, knowledge that has been
tested and proven. There is more experimentation going on right at
this point that will help build in this forgiving quality that I
mentioned.
Our attention has previously been concerned primarily with the
single-vehicle wreck. We must not lose sight of the fact that .some of
these se.me fea.tures that cáuse the problem for the single car have
caused the multiple-car wreck.
The limited-access facility has brought with it some problems con
cerning which our own acc1dent records, until just recently, were not
telling us the full story of just exactly what was happening.
To assure that good design practices are followed, I mention just
two items. First, for the past severa! years we ha.ve been having opera
tional reports made on completed facilities. These operational reports
have been made by patrol officers, design engineers, traffic engineers,
maintenance engineers, and people who are familiar with the a.rea.
These operat10nal reports lead to improved design standards and
have in fact been instrumental in not only changing standards for our
future projects, but have been making immediate modifications to
recently completed work.
It. is not unusual to go back and see things that need to be changed
almost. immediately after a project is finished, once the roadway is
placed under:traffic, and you can see what the behavior of traffic actually
JS.
Second, in order to forestan the construction of obsolete work, we
have recently formed a review team to look at projects in the planning
stage. Design engineers, traffic eng'Íneers, and other disciplines a.re
making recommendationi, to change contrnct. plans before the work
commences.
I think here is one of the most fruitful nreas and is resulting in
mimy, many chnnges which will be beneficinl.
I think that. this process of review should continue on through the
construction phnse ns well. And obviously from thc pictures that we
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have j!OOn here in the last few days, many changes could be made at
modest cost on the construction job itself, which would enhance the
safety of the motorist.
Mr. CoNSTANDY. That is fine. That is a very good statement.
Are you pleased or unsettled-what word would you use to charac
terize your overall impression Y
Mr. WIL80N. I think I am <leeply concerned about this problem,
and I think that, not only to u.c;e an old excuse, but I think that the
matter of communicating some of the very latest developments to our
people in the field who can do the most about it would be most helpful
here.
Mr. CoNSTANDY. Thank you. Mr. Skeelsl
Mr. SK.EELS. During these 31h days of hearings, Mr. Prisk has shown
the committee many examples of questionable h1ghway design. I would
like to point out that the good features were not emphasized.
Probably 95 percent of the design is excellent. The remaining 5
percent is what we have been seeing.
The deficiencies we have been shown are mainly concerned with
details that are safety hazards and indicate to me that the safety of
the traveling public has not always been the primary concern of the
highway des1gner. And this neglect has undoubtedly been
unmtentional.
I do not for a moment believe anyone would accu.se the designers of
our Interstate System of being unconcerned with the safety of the
traveling public. Rather, it is the result of other design
pressures,
such as cost, terrain problems, drainage problems, esthetics, the nece.'3-
sity used to establish standards and procedures, and the lack of infor
mation on this state of the art at the designer's level.
Overriding ali of this is the necessity to have the enthusiastic support
of top management at both the State and national levels. Without
this, the best qualified and most safety motivated design engineer is
helpless to put his design engineering in effect. Witb active top-level
encouragement, even a mediocre design engineer using only ordinary
commonsense should be able to improve on many of tbe design and
construction deficiencies that we have seen.
I hope these hearings will inspire the agencies responsible for high
wa.y design to compete with each other to produce the safest road.
Surely the influence of this committee will go far to achieve this
end. The following ste)?S might be considered:
First, that safety des1gn review boards be established at appropriate
level.s to catch as many deficiencies as pos.'3ible at the design stage for
new highways.
Second, that trnined inspection tenms check the finished highwa.y
for areas in which improvements could be made.
Third, that proven snfety designs be immediately adopted by a.U
States, even though they were developed by another State or another
agency.
Fourth, that new but unproven designs be evaluated by an unbia.sed
testing agency, and neither be adopted nor rejected on the basis of
opinion alone. Most of the designs of which we are critical were
thought to be good by somebo<ly.
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Fifth, that AASHO and other pertinent standards be undated and
written in sufficient detail so that the engineer will have an adequate
guideline from which to work.
Last, and most important, the top officials in all highway depart
ments, who in the final sense are responsible for approving or rejecting
projects, must motivate their entire staff to put safety first.
As a postscript, I would like to add that the nine Sta.tes whose
Interstate efforts were critically evaluated are typica.l of all States,
and their highways are neither worse nor better than the others.
Mr. 0>NSTANDY. Thank you, Mr. Skeels. Very good. Mr. Hufff
Mr. HUFF. First, Mr. Cha.irman, I would like to express my appre
ciation for the honor of ha.ving been invited to appear on th1s panel.
As far as criticizing the many, many iJlustrations of design that we
have seen, I believe tha.t. we have made statements over and over regard
ing them, so I will confine myself to generalizing.
It seems that guardrail and bridge rail connections might be listed
as public enemy No. l. Close behind that would be curbs and possibly
the massive ends of bridge rails. It is a.lso significant, I think, that the
insta.llations that we ha.ve seen, all being on the Interstate System,
<'ould meet the standards for the Nat1ona.l System of Interstate
Highwa.ys.
Now, I say standards for the National System of Interstate High
ways, and I mean that pe.rt of the standards which formulated in the
beginninp: a.nd was mandatory 'that ali Sta.tes follow. However, it must
be rememhered that there are other AASHO policies.
They are not called sta.ndards. They are called policies; and it is my
opinion that most of the insta.llations that we have seen would follow
wha.t ever is la.id out in those policies, insofar as they are covered.
Sorne of the items that we ha.ve seen are not covered in the sta.ndards
or the policies.
This m my opinion calls for a. need for upgrading and broadening
our-pa.rticularly our AASHO policies to cover these types of design,
both on the Interstate System and on other highway systems for tliat
matter.
For example, the width of shoulders should be examined critically as
to whether we are now designing a proper width shoulder. The guard
rail design should be examined critically, remembering that the guard
rail on a fill approaching the bridge is a flexible structure. When it gets
to the structure, it becomes a rigid structure.
Bridges ha.ve to be designed to carry trucks. It is entirely possible
that a flexible raíl should be run across the bridge, which would be a
secondary raíl inside the rigid rail. If a truck ran into the flexible rail,
it would go through the flexible ra.il and then be conta.ined on the
rigid rail. Wherens, ali passenger cnrs would be contained bv the
flexible rail.
•
Now, a good example of what AASHO is doing currently is the so
called Yellow Book, whi<'h wn.c, issued earlier this year. At recent
A.ASHO design committee meetin�I am not sure ,,·hether all have
done this, but. the ones I nm familia.r with-ha.Ye endorsed the so-called
Yellow Book u.s a de.'li�1 standard.
lt goes fnr beyond the spedfications of the standards 01· the poliC'ie.....__
Anot.her thing that I ha.ve been impressed with in these hearinirs
is the need for better correlation between the various disciplines in
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995
highway engineering. It has been stated that the bridge engineer goes
here a.nd the road engineer starts and goes the rest of the way. Now,
wherever that correlntion is not being done, I strongly recommend that
it bebrought into pla)' ns quickly as possible.
I might say that m our own State we have jointly-the divisions
handling bridges and ronds together with the traffic engineer-we have
joined together and think thnt we have the best solution that we know
how to make on tra.nsition from a road rail to a bridge raíl. I am not
sure that it is best, but we think it is the best that we have been able to
find.
Of course we need also to inform ourselves as to what we should do
to correct sorne of the deficiencies that we ha.ve seen here, and we all
know-although m_y State is not represented in these pictures-we do
have the ea.me kind of deficiencies as were depicted here.
We need to establish priorities on the worst and the most dangerous
deficiencies and get to work on them. I believe that the States should get
to the job as fastas possible.
Now, we are not going to be able to do all of them at one time.
Another comment I would like to make would be-and this I hope is
constructive criticism-1 ama little bit aíra.id that this oommittee has
tried to give too many answers tothe deficieneies.
We are a group of six engineers here.. We have our opinions, but you
mit!get s1x other engineers somewhere else a.nd say, well, and start
pi
.
g boles.
I thmk rather than us trying to give the ideas here before this dis
tinguished committee, we should develop through AASHO, which I
think is the most capable organization to do it, standards based upon
the great mass of research tha.t has been aecumulated during the last
10 years since the standa.rds were developed and base our designs on
that.
I believe somebody should say sorne good things a.bout our Interstate
System. because I know that in our Sta.te, and I ha.ve been in many other
States, the people like it.
They cango a great distance and at great ease, and I think one time
we thought-and I was in our de{>&rtment in my sa.me position before
the interstate progr:am wa.s init1ated-some of us thought that we
were building too plush a highwa.y, were just gold-plating and gilt
� a special system here; and many of us thought the people
woúlcfrebel against that.
I think we should be gratified tha.t they are with us a.nd are willing
nnd a.nxious and a.lmost make it manda.tory tha.t we make it even bet
ter than we have made it inthe past.
Mr. CoNSTANDY. Thiank you, Mr. Huff, for your very pertinent
remarks.
Mr. Chairman, Mr. Huff on June 5 delivered a paper to the AASHO
()perating Committee on Design for Region 3, at Indiana.polis, Ind.
TÍle title of it is "Highway Safety as Related to Design Involving
Fixed Objects."
I would like to ask to make that exhibit No. 9 a.nd with permission,
to print it in the record, providing the size of the transcript will allow
it. It is a very pertinent paper. I think it will add a great deal to the
recordstha.t we have here.
Mr. McCARTHY. Without objection, it is so ordered.
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996
(The document referred to,illustrationsomitted, follows:)
HIGllWAY 8AFETY AS RELATED TO Dt:SIGN INVOLVING FlXED OBJECT8
Over tbe past year, the toplc "Hlghway 8afety" has received CODBiderable
attentlon by automoblle clubs, law enforcement agencies, automoblle mano-
. facturers, clvlc groups, servlce clubs, and even tbe Natlonal Admlnlstratlon. Tbe
U.S. Congress has recognlzed the problem by passage of the Natlonal Trafflc and
Motor Vehlcle Safety A.et of 1966 and the Hlghway Safety Act of 1966. Tberefore,
tbe program thls afternoon Is both tlmely and In accord wltb thls growtng
awareness of tbe problem.
My dlscusslon Is concerned wltb only one phase of tbe over-all accldent
record, those lnvolvlng ftxed objects. However, 1t also representa one of tbe ftelds
In whicb we, as blghway engtneers, can exerclse the most lnftuence. We can exert
only a llmlted control over pedestrlan movementa or anlmals encroachlng opon
tbe roadway. We have even less control over a driver's actlODB and reactlon&
We can, however, remove ftxed Impedimenta or render them safer so tbat the
errant driver has a chance to recover control of bis vehlcle and retum uninjnred
totbe travelway.
Durlng 1966. ftxed obJect accidente In the State of Texas accounted for 14.5
per cent ot the total rural trafflc fatalitles. Altbongh tbls percentage is small
compared to tbe total record. tbe number of people represented thereby la not.
In human statlstlcs, thls percentage reflecta a total ot 500 people Jdlled In our
rural areas as a result of ftxed obJect accidente. lt Is, tberefore, obvlous tbat such
features deserve our lmmedlate attentlon.
As has been tbe case slnce Ita very inceptloo, tbe American A880Ciation of
State Highway Offlclals has taken the inltlative In tbls matter and In February
of thls year publlshed a report entltled "Highway Deslgn and Operatlonal Prac
Uces Related to Hlghway Safety." Tbe Speclal AASHO Trafflc Safety Commlttee
whlch complled the report Is to be commended for a Job well done. It Is my
fervent hope that the ftndings and recommendatlons contained thereln will gato
immedlate acceptance by tbe blghway professlon. Tbls publlcatlon covers, in
detall, the toplc whlch I am to dlscuss; however, I wonld Uke to cover severa!
features whlcb, over the years, have been of great concem to tbe Texas Highway
Department and, I trust, otber blgbway agencies.
BRIDGES AND SEPAJLATION 8TBUCTURE8
Wtth the advent of the Interstate Hlghway System, we began an accelerated
program lnvolvlng, among other thlngs, the constructlon of thonsands of brldges
and grade separatlons. Tbese lmprovementa have enabled us to redu.ce the poten
tlal hazards assoclated wlth at-grade cro98lngs; bowever, tbey lntroduced ftxed
objects In tbe way of plers and wlngwalls whlch have, unfortunat.ely, taken
tbelr toll of drivers. In 1966, Texas recorded Just over 1,000 rural accldents in
volvlng bridge ende or plers.
Tbe construotion of mlnimum length underpasses wlth short spans have lntro
duced plers adjacent to the shoulders whlch are entlrely too close to gtve tbe
driver any possibillty of error. In order to protect the sense of openness afforded
by our modero hlghway sectlon, the driver should experlence no constrlctlon when
passlng beneath a structure. The cent.er or outslde plers should be ellmlnated
entlrely or set back at least thlrt7- feet from the edge of the malo lane pe.vement.
Tbls would be an Ideal arrangemeot; however, it must be recognlzed tbat such
an arrangement Is not always possible or practica!.
Where thls Is the case 1md plers must be located nearer than thlrty feet from
the traveled way, they should be protected by an adequate length of gnardrail,
nnchored on the ende so that it may de,·etop lts fnll ribbon strength. Tbe Texas
Highway Department has been uslng such lnstallatlons for several years and we
nre quite encouraged by the aceldent record as1<odated wlth the same.
Attenuatlon devlces conslsting of energy nbsorblng material may eventually
prove to be the best meaos or protectlon. Severnl dlfferent types of devices are
currently belng considere<! imch as honeycomb mnsses of alumlnum, forests of
poste and large polyethylene contalners fllled wlth water. Bales of hay such as
nre used at the Grand Prix race represent a fairly l•ffectlve although somewhat
prlmitlve attenuntlon devlce. As most of you are nwnre, Texas has de,·eloped
breakaway slgn supports; however. the elimlnatlon of the hazard lmposed by
flxed sigo supports is of little value lf the slgn Is backed up by a pler.
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997
Narrow overpall8ell and brldges Ultewl&e present eome impoeing barriera which
have a bigh accident frequency. We, in Texas, bave lonc belleved that ali struc
turea should be wide enough to accommodate the full wldth of approacb roadway
and shoulders. A crown width bridge does, of conrae, cost more than doee a
restrlcted wldth strncture; however, consldering the length of time the strnctnre
wlll be in serv-ice, lt is an exerclse in false economy to permlt the initial cost to
dictate design. Trafflc Eafety and operation are enbanced by tbe wlder roadway.
Tbe driver is more comfortable on a wide structure. In tbe event of an emergency
stop, the wlde structure can accommodate the parked vebicle wltbont obstrncting
a trafflc lane. Studietr bave lndlcated that emergency stops along a conventlonal
faclHty occur eacb 10,000 to 12,000 veblcle miles whicb means approximately
eigbty mlllion stops per year on the Natlon's bigbways. If we are willlng to spend
mllllons of dollara to construct parking shonlders on the bigbways in between
brldges, why should we shrlnlt at spending a Httle more to extend thls refuge
11rea acrosa our structures?
Wben gnardrall is requlred on tbe approacbe11 to a strnctnre, lt sbould be con
tlnnoW1 across the strncture, anchored secnrely to the bridge and at the end of the
rail. Tbe bridge should not have any cnrbs if there are none on the approacbes.
In particular, constrnctlon of a RO called "Safety Walkway" should be avoided.
Wbile on the l!Jllbject, I mlght offer the obse"ation tbat altogether too mnch
eurbing has been Wled in the past along onr blgbways. As a general rnle, curbs
11bonld be tl8ed only wbere required for dratnage and, ln sncb cases, should be
easlly monnted by trafflc. A.n acceptable curb would be a Iaydown type wlth a
sugested rlse of tbree inches in a width of twelve to eighteen inches. A.ny bigber
eurb can tbrow a vehlcle out of control or lmpart a dynamic actlon tbat tends to
project tbe vebicle onto or over a protective rall.
Bridge parapeta and ralls sbould be deslgned so as to provide nnimpeded sigbt
distances to slde roads or rampa beyond tbe strnctnre. 0n many of our existlng
facilltles, we bave discovered that trafflc on an exlt ramp or frontage road,
stapped at tbe interaectlon, cannot see a throngb vebicle on tbe crossroad strnc
tlue nntll they pull ont into the lntersectlon. As a resnlt, a number of colllsions,
several involvlng fatalltles, bave resnlted. Tbese existlng sitnatfons can only be
corrected by alterlng the trafflc patterns or, at great expense, modifylng the
deaign.
DBAINAOII: 8TKUCTUU8
Our bighway cross eectlons are replete wltb deatb traps for tbe nnwary or
errant driver. A.mong the moet common are our installations for handling snrface
or cr088 drainage. Openlngs In mediana and outer separatlons, between culverts,
are prevalent in all areas of the Natlon. lf the culvert Is contlnuous, any number
of drop inlet designa with ralsed covPrs are enconntered. Sucb bazards can be
rather easlly ellminated by extPnsion of the culverts and lnstallatlon of flusb in•
Iets. Admlttedly, a flush lnlet 111 a malntenance headache since lt is susceptible to
being plngged by loose brush. dPbrilÍ or even a newspaper; however, a ralsed lnlet
or an open ditch is an even greater headache to apyone unfortnnate enough to rnn
loto lt. The only exceptlon to the use of flush lnlets would be where they are
located thlrty feet or more away from the edge of pavement.
Curb inlets aleo present a hazard to drlven, if tbey are located adjace-nt to the
travel way. As a general rule, the use of curb lnlets shonld be avoided; however,
where they are absolutely necessaey, tbey shonld be loca:ted on the back slde of
tbe curb.
The ends of culverui, headwalls and beadwall curbs, etc., should be located well
beyond the shouldPr edge and behlnd protectlve guardrall rather than adjocent
to or projectlng into the roadway. Agaln. thP guanlrall should be of tmfflclent
length, wHh an<.'hored ends, In order to Pnable lt to develop full rlbbon strength
if lt is struck by a vehide. Too often. a short length of rall, usually 12'
6" is lnstalled at culverui. The11e short ralls cannot contain a vehlcle. Thus the
only purpoee they serve Is to dellneate tbe hazanl; however, they are a hazanl in
tht>m!!elves.
TIIEES
For the past sevPral yPars we and thP hlghway lndustry have been mallgned
botb publlcly and privately for our lack of appredatlon of nature's beauty. We
have been attused of wlllfully 1md unfeellngly wreaklng havoc on areas of natural
beanty by constructlon of hlghways whlch disftgure the landscape.
Unfortunately, thPre have bepn casPs where o,·erzealous englneers bave diere•
garded the amenltles; however, Ido not agree tbat thls Is the case rather tban
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998
the exceptlon. A modern, well delllped blghwa)' 11 a thlng ot beanf:7. B7 jucHcloua
plantlng and landtdplng lt can be adapted to the terrain and natnral follage .,
tbat lt complementa ratber than detracta from tbe seenlc grandenr. What we
must gnanl agalnst, ho�ver, 11 becomlng too ovenetllons In onr beaut.Ulcatlon
etforts.
Aslde from thelr ablHf:7 to enhance a hlghway'• appearance, trees are atlll
a deadly menace to hlgh speed trame. Drivers and tbelr untortnnate paMengeN
are 91:lll belng dally malmed and kllled by trees on our blgbway system. In Texas.
last year alooe we recorded 788 accldentl'I on our rural system lnvoh1ng trees
ond tlbrnbs.
In DO case abould safety ever be compromtsed In tbe tnterests of beautlftcatlon.
No trees abould be planted or pennltted to remaln wlthln thlrty feet of a maln·
lane shoulder or wtthln twenty feet ot • ramp. No treea abould be planted or
permltted to remaln wtthln mediana le88 than 11eventy-tlve feet In wldth. Slnce
over twenty-tlve per cent ot hlgbway fatalltlea result trom vehlcles le&vlng tbe
road, trees sbould be removed on tbe outalde wlthln tbe limita of horl&ontal
curves. Inslde tbe cu"ee, they abould be removed or aet back • sufllcient diB
tance so tbat they do not llmlt algbt dl8tance.
We tlave developed break-awa7 mounts for our blgbwa7 signa and lllomlna•
tlon standards. Untll sucb time as an &rtlftclal break-away tree la developed,
tbey muat be consldered one ot our mejor roadslde hazards.
ABUTMICNTS AND an'AllffflO WALL8
Slnce abutments and retalnlng wall8 must by thelr veey natnre be cloeer tbaD
tblrty feet to the roadway, they must be contlnuous wtth DO protrudlng features
subJect to colllslon. Deslrably, they abould be at leaat twenty feet from tbe
roadway. U a cloaer locatlon la requlred, protectlve gnanlrall sbould be lnatalled.
Retalnlng walla or abutmenta abould not lmpalr algbt dlatance to ramp gorea or
algns. Retalntnr walls chould, al. coune, be avolded lt at all poeslble, thoa
reaultlng tn a much more open, pleaalng and eafer factllt:7.
UTILITIEB
Utlllty lnstallatlons are tbe nemesla ot many blgbway engtneera. They con
tribute nothlng to the appearance, operatlon or malntenance of our aystem. The
tangle ot utlllty Unes along many of our hlgbwaya aeverely detracta from thelr
appearance and they are a conatant beadache to ·our conatructlon and malnte
nance peraonnel Neverthelesa, we muat Uve wlth them, bence we must eatabUsb
some baste bousekeeplng rules.
All overbead Unes conatltute a hazanl by vlrtue of thelr aupportlng polea.
Due to tbe maaalve slze ot B-framea and towers, tbey ahould be kept completely
off the rlght ot way except at extremely wlde sectlona where they can be placed
beyond any reasonable po98lblllty of danger to trafflc. Ideally, overhead linee
should apan the entlre rlght of way wlth poles adJacent to or Juat outalde tbe
right ot way Une; however, lf a comproml.ae arrangement muat be accepted,
utility polea abould be no closer than thlrty feet to the maln lane ahoulden
or twenty feet to tbe ramp shouldera. Electrlcal transmlsslon Unes, of course.
pose the greatest danger to trafflc slnce any accldent resultlng In a pole knock•
down or damage could drop a "bot Une" across the hlghway. Telepbooe Unes do
not pose thiB danger; bowever, because telephone Unes cannot normally span as
great a dlstance as power linea, thelr pole placement Is a principal conslderatlon.
RailrOlll.d signa! devlces such as gnt,ee, flashing llghl's, crossbuck slgns. ere., con·
stltute amenace to trafflc dueto thelr usual proxlmity to the blghway at rallroad
hlghway crosslngs. I mlgbt menUon tbat Texas Is eurrently engaged lo a coopera•
tive research study lnvolvlng at-grade rallrood crosslngs. It ls our lntent to try
nnd develop a hazard ratlng of dltferent types ot crosslngs as well as determine
whether rnHroad crosslng signa ami slgnals -sbould be brougbt back lnto die
tamlly highway signa.
In municlpollties, ftre plugs and traffic signnls can be quite hazardoua. Most
f"treet sa'l:ions are n�sarily ronistructed on very restrkted rlght of way wltb
flre plugs, trafl.'c signal11, lllumi!11ltion stiandnrds, etc.. locuted 'between tbe C'llrb
and sldewalk. Ali sucb lnstallatlons Eihould be located as far away trom tbe road·
way as poaslble, preterably beyond the sldewalk area.
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