etab modelling

1. How to make ETABS
models
Note : for intermediate student in computer program not beginner
Please any note call me to discuss it
.

2. Exampl
e
: Our example
residential
building consist
of 20 story need
to make
ANALYSIS &
DESIGN with
ETABS
program
:

3. we choose default of program
Starting ETABS.
At start convert unit to the unit you work with
From file list – new model we get this massage

4. Define the Grid. When chose default this
window appears
 choose grid only
 in our example
number of stories
20
 story height 3m
 units kN -M

5. Plan View / 3D View
.
Your screen should
show one window
with a grid plan view
of your model and one
window with a grid
3D view of your
model.
Make sure the KN-M
is selected as your
units in the lower right
hand side of the
window.
Now is a good time to
save your model, so
click on the File/Save
and find a suitable
location for your file.

6. Now import your DXF file from *file / import / DXF floor plan
Choose your file and open it

7. Choose layers to
each element
(beams ,floors ,e
tc….)
Choose the story you insert
DXF in it

8. Define the Materials.
Next, we will define the
materials used in the model.
Concrete 40 & 60 grade will
be used.
The two materials will be
defined in successive steps.
Click Material Properties…
from the Define pull down
menu.
Click Add New Material…

9. For concrete 40 N/mm²
-Type C40 for the Material
Name.
-Select Isotropic for the Type
of Material.
-Type 2.5 for the Mass per
unit Volume.
-Type 25 for the Weight per
unit Volume.
-Type 28E06 for the Modulus
of Elasticity.
-Type 0.2 for Poisson’s Ratio.
-Type 9.900E-06 for the Coeff
of Thermal Expansion.
-Select Concrete for the Type
of Design.
-Type 40000 for f’c.
-Type 4600 for fy
-Type 4600 for fys.
-Click OK

10. For concrete 60 N/mm²
The difference here
Modulus of elasticity equal
0.2*60(grade ) + 20 = 32

11. Define the columns
.
Next, we will define the
concrete columns used in the
model. 25x80 cm columns
will be used.
The two concrete materials
defined in the previous step
will be used to define the
columns.
Click Define/Frame
Sections… from the pull
down menu.
Select Add Rectangular.

12. Define the 25x80 Cm column.
Type C25X80C60 as the
Section Name.
Select C60 as the
Material.
Type 0.8mfor the Depth.
Type 0.25m for Width.
Click OK.
Cracked section
design

13. Define the Shear walls.
Next, define the concrete shear
walls used in the model.
C60 shear walls will be used.
The concrete material defined
earlier in the tutorial will be
used to define the shear walls.
Click Wall/Slab/Deck
Sections… from the Define
pull down menu.
Select Add New Wall from the
Click to: menu.

14. Define the C60 shear wall.
Type W25C60 as the Section Name.
Select C60 as the Material.
Type .25 for the Membrane Thickness.
Type .25 for the Bending Thickness.
Select Shell as the Type.
Click OK.
Cracked section
design

15. Define the slab.
Next, define the concrete slabs
used in the model.
C40 slabs will be used.
Click Wall/Slab/Deck
Sections… from the Define
pull down menu.
Select Add New slab from the
Click to: menu.

16. Define the slab 22 cm post tension C40.
Type S22CMPT as the Section Name.
Select C40 as the Material.
Type .22 for the Membrane Thickness.
Type .22 for the Bending Thickness.
Select Shell as the Type.
Click OK.
Important note:-
The slab is post tension so
there is no cracked section
design that mean no
modifiers

17. Assigning slab section
Select the slab
Click wall/slab/deck section from
shell/area From assign menu.
Select S22CMPT.
Click OK.

18. Drawing & assigning column and shear wall
First drawing column Select the point u want to be a column
Click Extrude points to lines from
Edit menu.
Type -3 for dz.
Click OK.

19. Assigning column section
Select the column
Click Frame section from frame/line
From Edit menu.
Select C25x80.
Click OK.

20. Second drawing shear wall
-Select the lines u want to be a shear
wall
-Click Extrude lines to Areas from
Edit menu.
-Type -3 for dz.
-click Delete Source Objects.
Click OK.

21. Assigning shear wall section
Select the shear wall
Click wall/slab/deck section from
shell/area From assign menu..
Select W25C60.
Click OK.
Save your model.

22. Assigning Biers for wall sections
Select the shear wall each part alone
If the shear wall consist of HZ & VL
part (core) select HZ alone and VL
alone
Click pier label from shell/area from
assign menu

23. Write name P1 then click add new
name then ok
Do that for all walls HZ or VL
The name appears on the wall

24. Each wall appears its name on it

25. Edit the story data and relationships
.
Now, set up the story
relationship to aid us in the
development of the model.
Relationships between stories
are used to efficiently draw
elements on similar stories.
Select Edit Story Data from
the Edit pull down menu.

26. Continue to edit the story data and relationships
.
Set STORY 1 as a
Master Story by
selection Yes from the
Master Story Column.
Set ALL STORIES as
similar to STORY1.
Click OK

27. Activate the Similar Stories Command.
Now activate the Similar Stories Command so that elements
drawn on the master stories will be automatically drawn on
similar stories .
Select Similar Stories from the pull down menu located near
the bottom right hand corner of the ETABS screen.

28. Set the Building View Options
.
Now is a good time to save your model, so click on the
File/Save.
Now adjust the model to view options.
Select the Set Building View Options… from the View
pull down menu.
Click the Object Fill and Extrusion check boxes.
Click OK.

29. Assigning slab loads
Click static load case From Define menu..
Select slabs
Click Uniform From Shell/area loads From
Assign menu..

30. Load Case Name Dead
Load = 5
Direction Gravity
Load Case Name Live
Load = 3
Direction Gravity
Reselect slabs and click uniform surface loads

31. Click icon all to choose all members
Click diaphragms from shell/area from
assign menu
Add new diaphragm then write D2 then
ok the shape of diaphragm appears
Making diaphragm

32. Select all restraint
Click restraints (supports) from
joint/point from assign menu
Choose free restraint
Now good time to save your model
This step for replicating
Now the geometry
has ended we can
replicate the model

33. Click icon all to choose all members
Replicating the story
Click replicate from edit menu
Choose story then select stories u want to
replicate in for example in our model select
from story 2 to 20 then click ok

34. 3D Model View
The 3D view of your model should have
extruded filled-in elements.
Sometimes view changes are not updated
automatically. You may have to save the
file and exit ETABS. Then restart ETABS
to get the updated view.
Now is a good time to save your model,
so click on the File/Save.

35. Analysis And Design

36. Design option
Click concrete frame design
Change ACI 380-99 to BS811097

37. Design option
Click shear wall design
Change UBC 97 to BS811097
Change rebar unit from in^2 to mm^2
Change rebar/length unit from
in^2/ft to mm^2/m

38. Case of loading for seismic and wind
Click static load case from define menu.
Make a new case named QX type quake
self weight 0 auto lateral load UBC 97
1- seismic load (static)

39. Click modify lateral load.
Ct = .02
Over strength factor R = 5.5
Zone factor = .15
Importance factor = 1

40. Click static load case from define menu.
Make a new case named QY type quake
self weight 0 auto lateral load UBC 97
Click modify lateral load.
Ct = .02
Over strength factor R = 5.5
Zone factor = .15
Importance factor = 1
NOTE : we do cases –QX & -
QY when the structure is
not symmetric

41. Click static load case from
define menu.
Make a new case named
WX type wind self weight
0 auto lateral load BS 6399-
95
Click modify lateral load.
2- wind load

42. Click static load case from
define menu.
Make a new case named
WX type wind self weight
0 auto lateral load BS 6399-
95
Click modify lateral load.
Change wind angel direction
=90

43. 1- seismic load (dynamics)
Click response spectrum function from define menu.
Click add UBC 97 spectrum

44. Put Ca & Cv from UBC tables
At pages 2-34 , 2-35 chapter 16
Ca = .18
Cv = .25

45. Click response spectrum
cases from define menu.
Add new spectrum
Scale factor = 9.81/(R=5.5)
% Eccentricity = .05

46. Click Add new spectrum
Scale factor = 9.81/(R=5.5)
% Eccentricity = .05
NOTE :
U2 for Y case & U1 for X case

47. Any FORCE equal
MASS* ACCELERATION
So we need to get mass
source
Click mass source from
define menu .
-Mass definition from loads
-Load Dead multiplier 1 IF
residential structure live less
than 5 kn/m^2
We increase case of live IF
live > 5 kn/m^2
Load live multiplier .5
(commercial building )

48. *
Remove ACCEL Z

49. *
Number of iteration from 2 to 5 select 3
ow u can run the model
and see your result

50. -
Deformation according to
dead load case

51. Time period is very important

52. Support reaction
*
Click support/spring
reaction from show
member force stress
diagram from display menu
-
Choose the case u need
reaction in it

53. *
Click
Frame/pier/spandrel
forces
from show member force
stress diagram from
display menu
Frame/pier forces

54. *
Click Shell
stresses/forces from show
member force stress
diagram from display menu
Shell stresses/forces

55. Before resuming design we must careful some point
1
-
The last mode must reach percentage more than 90%
How to check that
?
Click show tables from
display menu
Select table modal participation mass ratio

56. The last mode must reach 90% or more than 90%
If modes not enough increase it from dynamic analysis parameter
form set option from analysis menu

57. 1
-
The base shear from dynamic analysis must equal base
shear from static analysis
How to do that
?
Click show tables from
display menu
Select table story shear

58. Select cases of seismic analysis

59. By diving Qx/SPECx factor is (6469/4200) = 1.54
By diving Qy/SPECy factor is (6469/4043) = 1.6

60. 1.7818
*
1.54
=
2.743972

61. 1.7818182
*
1.6
=
2.85090912
Now we can design with dynamic results

62. Concrete design
Shear wall design
Note : DCON15 to DCON26 removed
because its cases for static analysis in
concrete and shear wall design and
we use dynamic analysis in design