How road quality is ensured in the construction industry.The PowerPoint explains the question.

1. STEPS OF THE QUALITY CONTROL FOR
CONSTRUCTION OF A FLEXIBLE PAVEMENT
Rajib Chattaraj
Superintending Engineer
PWD, West Bengal

2. A. EMBANKMENT/SUB-GRADE/BACKFILL
 The material shall be soil, moorum, gravel, reclaimed
material from pavement, fly ash, pond ash, a mixture
of these or any other material as approved.
 Clay having LL exceeding 50 and PI exceeding 25 is
not suitable.
 Fill material with expansive clay should not have Free
Swelling Index exceeding 50 percent.
 When expansive clay having free swelling index value
less than 50 percent is used as a fill material, subgrade
and top 500 mm portion of the embankment just below
sub-grade shall be non-expansive in nature.

3. A. EMBANKMENT/SUB-GRADE/BACKFILL
i) Maximum dry density requirements of embankment and
sub-grade materials (as per table 300-1 of 5th Revision)
are as follows:
Sl.
no.
Type of Work Maximum laboratory dry
unit weight tested as per IS:
2720 (modified proctor
method) (part-8)
1. Embankments up to 3 mt. height, not
subjected to expensive flooding
Not less than 15.2
kN/cu.m.
2. Embankments exceeding 3 mt. height or
embankments of any height subject to
long period of inundation.
Not less than 16.0
kN/cu.m.
3. Sub-grade and earthen shoulders/
verges/backfill.
Not less than 17.5
kN/cu.m.

4.  Apart from that, the required CBR value, as specified in design, if
any, should also be achieved.
 If the soil is unsuitable to satisfy the above criteria, it should be
replaced by suitable soil or modified by suitable methods.
 After excavation, before putting on the subsequent layers,
compaction of ground supporting sub-grade or embankment
has to be done in accordance to cl. no. 305.3.4 of 5th. Revision.
 Field density has to be checked in accordance with IS: 2720 (part
28, Sand replacement method) as per clause 903.2.2 of 5th
revision. Degree of compaction compared with laboratory
maximum dry density for sub-grade, backfill and earthen
shoulders should not be less than 97% and for embankment it
should not be less than 95%. (Table 300-2 of 5th Revision).
 According to clause no. 903.2.2 of 5th revision, the acceptance
criteria for tests on density is as follows :

6. TOLERANCE OF SURFACE LEVELS OF SUB-GRADE IS + 20 MM (AS
PER TABLE 900-1 OF 5TH REVISION).
Picture of rolled and levelled subgrade

7. B. Granular Sub-Base (GSB)
 When GSB layer is comprised of two layers- upper & lower, the upper
GSB layer should be treated as drainage layer and the lower GSB
layer should be treated as separating/ filler layer.
 The minimum thickness of drainage and filter layer each will be 100
mm.
 Gradation III and IV of Table 400-1 should be used as drainage
layer.
 Gradation I, II, V and VI of Table 400-1 should be used as
filter/separation layer.
 If for structural requirement, the thickness of GSB layer is less than
200 mm, and both drainage and filter layer can not be provided
separately, the minimum thickness of the single drainage cum
filter layer shall be 150 mm from functional requirement.
 Gradation V and VI of Table400-1should be used in that case.
[As per Clause 7.2.1 and cl. 7.2.2 of IRC 37(2018)]

8. Gradations of GSB

9. GSB – CONTD..
 The materials chosen for GSB should be such that
physical requirements as per table 400-2 of 5th
Revision are satisfied.
Aggregate Impact
Value (AIV)
IS: 2386 (Part 4) or IS:
5640
40 Maximum
Liquid Limit IS: 2720 (Part 5) Maximum 25
Plasticity Index IS: 2720 (Part 5) Maximum 6
CBR at 98% dry
density (at IS: 2720-
Part 8)
IS: 2720 (Part 16) Minimum 30 unless
otherwise specified in
the Contract

10.  The required CBR value as specified in design should also
be achieved with the minimum value of 30%. Material
passing through sieve size 425 micron has to be taken for
testing of liquid limit and plasticity index.
 For all important roads, use of laterite, moorum type of
material in GSB should be avoided even if these materials
would meet the required criteria of liquid limit and plasticity
index after mixing some amount of sand. It is experienced
that chances of these material forming cake are much more
and thereby blocking the drainage of pavement which
would result in cracks/settlement/failure of the much costlier
upper layers of the pavement.

11.  Field checking of Sub-grade layer done with laterite-moorum-sand mixture
which was discarded.

12.  Design mix of GSB layer has to be prepared and approved by
competent authority which should comprise of mix proportion of
different ingredients, their physical characteristics, combined
gradation and methodology for mixing (i.e. Job mix formula),
Laboratory density (Modified Proctor maximum dry density as
per IS: 2720 Part: 8) and optimum moisture content.
 Field checking of GSB would include gradation analysis which
should be close to the job mix formula and also within the range
of upper and lower limit, LL and p.i value for the material passing
425 micron should be within specified limit, the field density
checked in accordance with IS: 2720 (part 28, Sand replacement
method) has to be achieved upto at least 98% of the
laboratory density. [To test the layers exceeding 150 mm but
not exceeding 250mm in thickness and for fine, medium &
coarse grained soil, large pouring cylinder method has to be
adopted.]
 For control of compaction and acceptance criteria, same
clause 903.2.2 of 5th. revision as stated above shall be
applied. The frequency of the tests to be carried out will be
as per table 900-3 of 5th. revision.

13.  Tolerances in surface levels is + 10 mm (in case of flexible
pavement) and + 6mm (in case o concrete pavement) as
per table 900-1 of 5th Rev.
 Grading III & IV of Table 400-1 of 5th. revision being gap-
graded is suitable for drainage layer. (Not grading V & VI
as mentioned in cl. no. 401.2.1 of 5th revision, it is wrongly
written there. IRC 37(2018)) has clarified this very clearly.
 If the thickness of the compacted layer does not exceed
100 mm, a smooth wheeled roller of 80 to 100 kN weight
may be used.
 For a compacted single layer upto 200 mm, the
compaction shall be done with the help of a vibratory roller
of minimum 80 to 100 kN static weight capable of
achieving the required compaction. [Cl. 401.3.2 of 5th
revision]

14.  During mixing, transporting & laying, upmost care should be
taken so that no foreign material specially clay particles
are mixed with GSB materials. If so, during rolling and
visual inspection such material should be detected and
removed.
 The tendency of stacking GSB materials at site for days
together should strictly be avoided. At the end of each
working day, no stack of GSB material should be left at
site without being laid.
 GSB bed should be covered with subsequent upper layer
as early as possible soon after achieving desired degree
of compaction and level.

15. Picture of Laying GSB material and the field testing of the same

16.  C. Granular Base Course WBM/WMM.
 WBM works are not generally been adopted in project
works nowadays, its use are more or less confined to
maintenance natured work only (deeper pot-holes
mending). But during maintenance natured work, wherever
WBM is done, it should be ensured that there is no
bituminous layer or any other impervious natured layer
underneath the WBM layer constructed. In clause
no.404.3.1 of 5th. revision it is also stated in the same
way. If so, even the deeper pot-holes are also advised to be
mended with bituminous work. This is equally applicable in
case of WMM too.

17.  It is often experienced in site that WBM being a manual operation, is not
done following the proper norms. The coarse aggregates are not rolled
properly to ensure mechanical interlocking, screening materials are
stacked or dumped on WBM bed blocking the voids to be properly filled
up, the grading of the screening material (type A & type B) and the
property of the binding material where ever required are not as per
specification etc. To avoid this, it is advised to follow clause no 404 of 5th
revision properly while executing this item. In 5th. revision, grading-I of
coarse aggregate(as that was in 4th. revision) has been removed,
only grading 2 and grading 3 of 4th. revision has been retained.
Changes have also been made from 4th. revision to 5th. revision in
grading of type-B screening materials .
 (ii) Sand should be avoided to be used as fine aggregates with stone
chips as coarse aggregates, though it may result better permeability but
certainly at the cost of strength and stability because the presence of
natural sand having rounded surface will facilitate rutting.
 (iii) The materials chosen for WMM should satisfy the physical properties
as per table 400-12 of 5th rev.

18. WMM

19.  The criteria of meeting the plasticity index value for the
material passing 425 micron is very important and crucial for
proper functioning of WMM. It is advisable to collect field samples
of WMM to test these criteria. By checking this, the chances of
mixing up clay particles/plastic fines with WMM materials would
be restricted. It is seen that mixing up of clay particles or
plastic fines with WMM materials is one of the main ways of
failure of WMM or more precisely causes the failure of the
bituminous layer laid over it. . Visual inspection should also be
done by experienced engineers to find out the lumps if any, which
are the sign of presence of plastic fines. If such lumps are found
on laid WMM bed, those should be removed with surroundings
and replaced by WMM materials, not by stone dust or coarse
aggregate alone. Then proper rolling has to be done to achieve
required degree of compaction level so that by no chance, these
spots remain as weak spots. Regarding this, cl. 406.6 of 5th
revision should be followed.

20.  WMM (and also GSB) is unbound materials. Thus, plying of
vehicles over GSB and WMM bed is prohibited. In case of
construction vehicles, plying in restricted speed has to be allowed
but as minimum as possible by not prolonging the construction of
upper layer over it.
 To avoid stripping of the materials from WMM bed, soon after
achievement of desired degree of compaction, level and drying of
surface moisture, WMM bed should immediately be primed and
after the curing time of the priming coat, it should be covered by
bituminous layer with no further delay.
 (v) Design –mix of WMM has to be prepared and approved by
competent authority which should comprise of mix proportion of
different size of aggregates, their physical properties, combined
gradation (i.e., job-mix formula) as per table 400-13 of 5th.
revision, modified by table 2 of IRC:109(2015)[Guideline for
Wet Mix Macadam, First Revision], laboratory density (Modified
Proctor dry density as per IS: 2720 Part-8) and optimum moisture
content.

21. Ref: IRC:109(2015)

22.  (vi) Field checking of WMM would include gradation analysis which
should be close to the job mix formula and also within the range of upper
and lower limit, plasticity index value for the material passing 425 micron
should be within specified limit, the field density(MDD) checked in
accordance with IS: 2720 (part 28, Sand replacement method) has to be
achieved upto at least 98% of the laboratory density. [To test the layers
exceeding 150 mm but not exceeding 250mm in thickness and for fine,
medium & Coarse grained soil, large pouring cylinder method has to be
adopted.]
 For control of compaction, same clause 903.2.2 of 5th. revision as
stated above shall be applied. The frequency of the tests to be carried
out will be as per table 900-3 of 5th. revision.
 (vii) Tolerances in surface levels is + 10 mm (in case of mechanically laid
WMM) and + 15mm. (in case of manually laid WMM) as per table 900-1 of
5th Rev. For any correction of level, method as per cl. 406.6 of 5th rev.
has to be followed.
 (viii) During mixing, transporting & laying, utmost care should be taken, so
that no foreign material specially clay particles are mixed with WMM
materials. If so, during rolling and visual inspection such material should be
detected and removed.
 (ix) The tendency of stacking WMM materials at site for days together
should strictly be avoided. At the end of each working day, no stack of
WMM material should be left at site without being laid.

23. Continued
..............
Acceptance criteria for degree of
compaction :
Ref: IRC:109(2015)

24. Picture showing formation of lumps in WMM
layer due to presence of plastic fines

25. Picture showing removal of damaged WMM mixed with plastic
fines.
If the lump or cake formation by the presence of plastic
material is retained somehow in WMM, it will retain water
during its functional life and in turn will cause pumping action
to cause cracking in the upper bituminous layer.

26. Such fatigue cracks in the bituminous layer is
suspected to be caused by the effect of pumping
action by the entrapped water in the plastic material
underneath.

27. PRIMING OF BASE COURSE
A good prime coat should meet the following requirements:
1.It should penetrate at least 8 to 10 mm into the WMM.
2.It should normally be absorbed within 48 hours.
3.It should not be excessive on the surface of WMM. No prime coat is
better than excessive prime coat because the latter is detrimental to
the flexible pavement.
Cationic bitumen emulsion SS-1 Grade conforming to IS:8887
only and not as per ASTM D 2397 shall be used as primer.
Courtesy : Prof P S Kandhal

28. CHECK-LIST CUM GUIDELINE FOR BITUMINOUS
WORK (DENSE GRADED MIX LIKE DBM, BC)
 A. Mix design and selection of material related
 Mix design of dense graded bituminous mixes is very
important and should be very carefully done. It has to
address strength, stability, durability, rut resistance,
fatigue resistance, resistance to temperature cracking,
moisture damage etc. so many things out of which many
are conflicting to each other. The ranges for different criteria
for Marshall Method of bituminous mix design has been laid
down in section 500 of 5th revision and IRC: 111 (2009).
However, details of the Marshall Mix design procedure are
laid down in MS-2 of Asphalt Institute, USA which is
followed internationally.

29.  The basic concept as well as the trick of success of the
bituminous mix design is to compact the mix to a desired air
void, not to compact the mix to its maximum possible density
like it is done in case of soil, non-bituminous mixes and also non-
dense graded bituminous mix like BM. This desired air-void
range of the mix is 3-5% compared with the mix with no air void
which is called theoretical maximum specific gravity of the
mix. This 4% air void (mid of 3-5) of the mix is desired to be
achieved after attaining the saturation level of compaction that is
generally achieved after 1-2 years of plying of traffic on the
finished work which is called secondary compaction. As per MS-
2, it is advisable not to depend on single criteria of mix design,
but it is also said that if one criteria has the maximum influence
on the overall durability and performance of the mix with desired
level of services, it is the appropriate level of air void. It is
internationally established fact that 4% air void is that
appropriate level after secondary compaction for best optimum
service .

30. MAXIMUM THEORETICAL SPECIFIC GRAVITY AS
PER ASTM D 2041

31. VIDEO OF THEORETICAL MAXIMUM SPECIFIC GRAVITY
TEST AS PER ASTM D 2041/ AASHTO T-209

32.  Therefore, the main aim of the Marshall Method of mix
design is to achieve such a mix, so that the mix attains air
void nearing 4% after secondary compaction where as it
also meets the specified range of the other criteria like
stability and flow and three volumetric properties -the first
one is the most important i.e, air void or void in mix, (VIM),
and the other two are voids in mineral aggregate (VMA)
and voids filled by bitumen (VFB).
 The ranges of these criteria is laid down in table 500-11 of
5th. revision. Density of the mix is also determined though
there is no specific range mentioned of the compacted
density of the mix because it depends on specific gravity of
the individual ingredient which may vary from source to
source.

33. Picture of taking Marshall Moulds, Moulds and the Marshall stability testing
Machine

34.  The volumetric properties are indirect indicators of the
performance of the mix. These are not direct
performance parameters.
 However, it is established by international research that
volumetric properties of the mix are much more
important than physically measured criteria like
stability & flow for durability and overall performance of
the mix.
 Further improved version of Mix design method like
Superpave and very recent development as Balanced Mix
design also uses the volumetric properties of the mix.

35. Ref: MS-2, Seventh revision
What is Air Void, Voids in Mineral Aggregate and
Voids filled by bitumen

36. IMPORTANCE OF THE VOLUMETRIC PROPERTIES
OF A BITUMINOUS MIX
In the Fatigue equation of IRC 37(2018), a factor “C” has been
incorporated which is determined by the volumetric properties

37. The items of Job-mix formula of dense graded bituminous mixes
should be as specified in cl. 505.3.3 of 5th rev./ Cl. 4.3 of IRC: 111.

38.  Gradation of DBM Gr- I and DBM Gr-II should be as per
table 500-10 of 5th Revision and that of BC Gr.-I and BC
Gr.-II should be as per table 500-17 of 5th Revision. The
same is also laid down in table 7 of IRC: 111 (2009).

39.  As such nothing in particular has been mentioned in 5th Revision or IRC:
111 about how to choose and fix the combined gradation of DBM or BC
mix. But it is an important aspect of mix design. In absence of that, many
engineers follows the mid-point gradation (mean of upper and lower
limit of each sieve size). It is not the best idea. Out of some school of
thoughts, optimising "void in Mineral Aggregate, VMA" is one
established way by international research for choosing the combined
gradation. 3 to 4 gradation curves may be derived by varying the proportion
of different sizes of mineral aggregates being within the range of upper and
lower limit. As least 2 sets (each set comprises of 3 samples) of Marshall
moulds have to be cast with bitumen content nearing design bitumen
content of the particular mix under consideration e.g. DBM Gr.-I, BC Gr.-II
etc. and different parameters say stability, flow, density and volumetric
properties have to be determined . The gradation curve which gives
higher VMA and at the same time satisfies the range of other criteria
may be chosen as the design gradation curve. The combined
gradation curve which gives the maximum density, cannot be chosen
as the design gradation curve because the aim is not to get the
densest mix.
 The implication of Air void, VMA and Voids filled by bitumen has been
discussed in details in MS-2.
 The minimum VMA criteria laid down in table 500-12 of 5th revision is
incomplete. Table 8 of IRC: 111 (2009) should be followed regarding this.

41.  There may be confusion in correctly interpreting the foot-note below table
500-10 or table 500-17 of 5th revision, where in, it is stated that in case
aggregate have specific gravity more than 2.7, the minimum bitumen
content may be reduced proportionately. It is the minimum bitumen
content that may be reduced (i.e. 5.2% for BC gr-I, 5.4% for BC gr.-II like
that), but not the design bitumen content. The design bitumen content
as derived by proper design-mix cannot be reduced.
 If the Water Sensitivity Criteria of the mineral aggregates used for the
mix are unable to satisfy the specified value as per table 500-8 of 5th.
revision, filler should be used (cl. 505.2.4 of 5th. revision). Hydrated
lime [Ca(OH)2] has been found by research to be the best filler in
bituminous mix. It is having the added advantage of anti-oxidant and anti-
stripping property. Cement as filler in bituminous mix has no role to play as
binding material (which is a result of chemical reaction with water in
cement-concrete structures) other than being a finely pulverised material
of a uniform range of size. Thus, cement as filler in bituminous mix
should be discouraged, being a costly material but its capacity not being
fully utilized in bituminous mix. Bag-house fines in Batch-Mix-Plant can be
a suitable alternative to be used as filler or more precisely saying as fines.
In that case, it should be appropriately taken into account of the design-
mix and rate analysis too.

42.  Selection of appropriate grade of binder i.e., bitumen is very
important. In IRC 37(2018) Table 9.1 has categorically laid down
the provision of the grade as per the traffic volume.

43.  For modified bitumen, the designated IRC code is IRC: SP: 53. But
there is dispute whether to follow its 2002 version as 2010 version.
Therefore, it is advisable to follow BIS code for modified bitumen i.e., IS:
15462(2019), recently revised basedon PG(performance grade).
 Wherever CRMB is used as modified bitumen, engineers should be
extra careful, so that the quality of CRMB reached at site and before
being consumed in HMP would meet the required specifications as per
codal provisions. Storage of CRMB in storage tank in plant site for a
longer duration is strictly prohibited. A separate BIS code for Rubber
modified bitumen IS:17079(2019) has been published.
 Wherever PMB is specified to be used, between elastomeric and
plastomeric variety of polymer modified bitumen, it is advisable to use
PMB (E) i.e., elastomeric variety.
 The recommended grade of bitumen for Mastic Asphalt is also different
as laid dawn as per cl.516.2.1 of 5th. revision and cl.3.1 of IRC: 107
(2013). It is advisable to use 85/25 grade of industrial bitumen ( as per
IS: 702) as recommended in IRC: 107 (2013) except in cold region where
the temperature is below 100C when paving grade bitumen VG-40
should be used as recommended in 5th rev. [ Temperature should be the
guiding criteria, not altitude as it is stated in IRC: 107 (2013)].

44. B. FIELD CHECKING OF BITUMINOUS WORK
 The range of temperature of dense graded bituminous mix
during different operations like mixing, laying and rolling
for different grade of paving bitumen has been laid down in
Table 10 of IRC: 111 (2009) or table 500-2 of 5th. revision .
Maintaining correct temperature for different operations is one
of the key factor for the success of bituminous pavement. So it
should be strictly followed and written record for temperature
of the daily bituminous work has to be maintained.

45.  For HPMs of batch mix type which is desired to be
employed for BC/DBM mix, the production of bituminous mix
have to be monitored by taking computer print outs of at
least first three batches, last batch and minimum one print
out of a batch per hour of production for everyday's work.
 For bituminous work of everyday, the print outs of the
consumption of aggregate and bitumen have to taken and
cross-checked with physical work and consumption of
material at site and recorded in a register which will time to
time be checked by departmental engineers and consultants
wherever employed.

46. Picture of Batch type of Hot Mix Plant

47.  Bitumen content of the mix have to be checked at random
throughout the day's work. Generally centrifuge extractor
machine (as per ASTMD 2172) is engaged for determination of
bitumen content. To test the correctness of this equipment,
bitumen content of a mix of known bitumen content (which may
be prepared in laboratory by mixing with weighed aggregate and
weighed bitumen) may be determined and check + error (if any) in
% bitumen content. It may be taken into account while testing
bitumen content of the mix produced from HMP with that
centrifuge extractor testing equipment. The tolerable limit of the
bitumen content from the design bitumen content is + 0.3% as
per provision of table 500-13 or table 500-18 of 5th revision. That
means, if the design bitumen content of a DBM mix is 4.5%,
during construction operation, the bitumen content of the
DBM mix from 4.2% to 4.8% is acceptable. But it should not be
perpetually on either of the upper or lower side. Ideally, the
bitumen content should be plotted wrt the design bitumen content
as the datum line. The plots of the bitumen content as
executed should be evenly distributed from upper to lower of
the datum line.

48. Picture of bitumen extractor machine
v) After bitumen extraction test, gradation test of the mineral aggregates (if
sufficient aggregates are not available after extraction of just one sample,
two/three mix materials sample would be extracted) have to be done and tallied
with the approved design mix -- Job Mix Formula(not with the range). The
variation should be within the tolerable limit for different sieve size as per
provision of table 500-13 (for DBM) & table 500-18(for BC) of 5th revision as the
case may be or as per table 9 of IRC: 111 (2009).

49. Register page showing the gradation test after bitumen extraction of DBM
mix

50.  Testing of field density of the bituminous layer is important. As per
cl. 505.3.5 of 5th revision, both for DBM and BC layer, the field
density of the bituminous layer should be at least 92 % of the
theoretical maximum specific gravity of the mix (Gmm) in
accordance with ASTM D2041, obtained on the day of compaction
just after compaction with the roller (compaction plant). Previously
it is said, for embankment the minimum density achievement
criteria is 95%, for sub-grade it is 97%, for GSB and WMM it is
98%. These % are compared with laboratory density. But for
dense graded bituminous mix, it is 92% because it is
compared with the density with no void which is called the
theoretical maximum specific gravity. It is presumed that after
the effect of moving traffic on the finished work (which is called
secondary compaction) for 1 to 2 years, the degree of compaction
of the bituminous would settle to a saturation point nearing 96-
97% of theoretical maximum specific gravity (Gmm) leaving 4 to
3% air void. In this level of air void, the mix would be stable. If it is
below 3%, plastic deformation in form of rutting in bituminous layer
will occur, if it is above 5%, the mix will have enough space for
moisture damage and accelerated oxidation of bitumen causing
early damage of the mix. Air void level more than 5%, means the
mix may be deficient in bitumen content which will affect durability
and cause stripping, ravelling etc too.

51. ACCEPTANCE CRITERIA FOR TESTS ON DENSITY SHALL BE AS
PER CLAUSE 903.4.2 WHICH IS AS FOLLOWS:
o It is very important to keep good record of Theoretical Maximum Density
(Gmm) of the plant mix everyday and the particular location where the mix
produced on a day is laid. If there is possibility of change of any parameter of
mix design, it should be separately marked.
o The density of the core cut from the bituminous layer of any location should be
checked with respect to the Gmm of that particular location.
o Properly correlating of the field cores to the respective Gmm is very
important, without that, it would be a mere theoretical exercise and of no
practical use.

52.  It is also said in cl. 505.3.5 that core has to be taken after
24 hours of laying and compacting the bituminous layer,
because before 24 hrs, it may not be enough hard or sound
to drill the core with defined cylindrical shape. But at the
same time, after 24 hrs, if it is detected that the desired level
of density has not been achieved, no rectifying measures
can be taken because after 24 hrs, the temperature of the
bituminous layer would come down to ambient level and at
that time further compaction would just not be possible.
Here the advantages of instant digital density gauge (like
nuclear density gauge, electrical density gauge or such
attachment fitted with sophisticated compaction
machineries, intelligent compaction) may be taken while
rolling operation is in progress.

53. Picture of Nuclear
density gauge
These gauges, if duly calibrated, can give the idea of level of
compaction to an accuracy level of 98-99%, from where the idea can
be obtained whether further rolling is required or not instantly, i.e.,
when the mix is still hot. But the result from these gauges cannot be
taken as acceptance or rejection criteria. It is only to be done by
taking cores from the laid and compacted bed.

54.  The procedure of determination of theoretical maximum
specific gravity of the mix has been laid down in Annex B
for IRC: 111 (2009) which may be consulted for
reference.
 The other routine test/checks as per section 900 of 5th
revision. have to be carried out for both non-
bituminous(table 900-3) and bituminous work (table 900-
4).
THANK YOU