ETABS Prob Examples

ETABS Extended Three dimensional Analysis for Building System ********

SYLABUS:

1. Introduction & Modeling : -Introduction

- Objects

- Templates - Floor Information

- Modeling / geometry

2. Material & section Properties : - Material Properties

- Section properties - Wall/Slab/Deck sections.

3. Draw and options :

-Drawing of point, line and area objects. - Reference lines and Planes.

4 . View, selection & Options :

- View Management

- Object selection - Options and Preferences.

5. Assignment --Structural options :

- Point object assignments. - Line object assignments.

- Area object assignments.

6. Assignment – Loads - Load cases- Dead loads/Line loads/

Wind loads/ Earthquake loads. - Load Combinations

- Load assignment.

7. Analysis :

- Analysis options . - Analysis log.

8. Text & Graphical output :

- Text output - Un deformed shape and load plots.

- Deformed shape and result plots. - Energy plots.

9. Editing option :

- Cut, Copy and Paste. - Replicate.

- Frame and area meshing. - Point and line extrusion.

10. Text input and File Export / Import :

- Text input file - Export options

- Import options.

11. Concrete Design using Indian Code IS 456- 2000: - Design of concrete beams and columns.

- Design of Shear Walls and lintels. - Design of Composite Beam.

12. Steel Design using IS 800-2007 : - Design of Steel members.

- Optimization options.

****

ETABS CABABILITIES

o Construction sequence analysis.

o Push over analysis. o Shear wall design.

o Live load reduction for upper floors. o Earthquake forces can be applied in anu angle (not just X and Y

alone) o Modeling tapered concrete beams.

o Floor load for irregular panels, that is easy to do. o Design of columns with cross section of any arbitary shape (including

Y, L, +) o Diaphragm action.(with earthquake loads and wind loads

automatically applied on the diaphragm centre) o Automatic lumping of masses for earthquake .

o Choice of Eigen or Ritz vector for Response spectrum analysis.

o Auto calculation of beam reinforcements based on moments at column face, rather than at column centre line and column

reinforcements based on moments at beam soffit, rather than at beam centre line.

o Rigid Panel zone modifier. o Facility for design as per IS 13920 (Ductile drtailing)

o Additional software for foundation design especially mat (SAFE software).

o Not support for sloping roofs. o ETABS uses matrix method of structural analysis.

(Staad also uses Matrix method of structural analysis & FEA for plates.

o 3D rendering in ETABS: Go to view menu � Select set building view options. In first column

button, check Extrusion and object fill.

Disadvantages :

ETABS can not generate floor loads. You have to model slabs as plate element & mesh it and apply floor loads on it. Otherwise modeling

and rebar detailing is far easier in ETABS. ETABS documentation gives no details of the solver it uses other than

referring to it as “standard solver”.

ETABS TIPS

***** 1. Analysis options :

ETABS has many analysis option which includes - P delta analysis .

- Dynamic analysis - Eigen vectors analysis.

- Ritz vectors analysis. - Linear analysis.

- Non linear analysis. - Static Non linear analysis.

- Construction sequence analysis.

2. Locking and unlocking the model : From Main menu � Option � Lock model / unlock

Check model : Before running analysis use check model to ensure that objects do not

overlap and that objects are connected. From Main menu � Analysis � Check model ----

3. Editing the model :

Edit � edit grid data.

� edit storey data. � edit reference plane.

� edit reference line. � Add model from template (2D frame or 3D frame).

� merge areas.

� Joint lines/ Joining selected beams or selected columns.

4. Text/ Graphical output : To view loads :

From Main menu � Display � Show loads � Frame /Line ---

To view design info :

From Main menu � Design � Concrete frame design � Display design info.

To view other Tables :

From Main menu � Display Show Tables � Select required boxes.

Exporting the files :

From Main menu � File � Export � Save model as etabs.e2k text file (like a Staad editor file )

We can also export to SAP or SAFE or Excell data base or .dxf file.

Importing the file :

From Main menu � File � Import � ETABS.e2k. Text file or Staad file or Struds.

Options/Preferences:

From Main menu � Option � Preferences � Concrete frame design

(Select code and other parameters) - Shear wall design

- Reinforcement/bar sizes (add new dias or modify existing)

- Live load reduction.

Auto saving the model : From Main menu �Option � Auto save model � set time � Ok.

Loads :

Combination of existing loads - Envelope of combinations.

To draw Column or beam to required location :

There is no move command here. Set snap grid on and draw column or beam any where we want.

To draw secondary beam at required distance

Set plan view to required floor in left window � Right click on the screen (not on the slab) � Plan fine grid spacing � Plan fine grid

spacing =500 (say) � Ok. From Main menu � Draw � Snap to � Fine Grid � From Main menu�Draw line objects� Draw line �

Property = --- (Moment release=Pinned and draw the beam at

required distance. To get out from line grid (above option):

Draw � Snap to � Fine grid. *****

ETABS Extended Three dimensional Analysis for Building System

Example 1: No. of stories : G+3

No. of bays in X Direction : 2 No. of bays in Y Direction : 3

Spacing in X Direction : 3500

Spacing in Y Direction : 4500 Typical Storey height : 3000

Basement height : 2000 Concrete Grade : M20

Steel Grade : Fy415 Column Sizes C1 (Corner Column) : 230 x 300

C2 (Side Column) : 230x 380 C2 (Inner Column) : 230x 460

Beams B1 : 230x 330 B2 : 230x 406

PB : 230x300 Slab Thickness : 125mm

C3 = 230 X 460

C1 = 230 X 300

C2 = 230 X 380

COLUMN:

PLINTH BEAM - PB 230 X 300

B2 = 230 X 406

B1 = 230 X 330

BEAMS:

B1B1

B1B1

B1B1

B2

B2

B2

C1C2C1

C2C3C2

B2

B2

B2

B2

B2

B2

C2C2 C3

C1

B1 B1

C1C2

CBA

4

3

2

1

4500

4500

45

00

35003500

STOREY-5

STOREY-4

STOREY-3

STOREY-2

30

00

STOREY-1

BASE

B1 B1

B1B1

B1 B1

PB1PB1

30

00

30

00

30

00

20

00

BEAMS:

B1 = 230 X 330

B2 = 230 X 406


COLUMN:

C2 = 230 X 380C1 = 230 X 300

C3 = 230 X 460

STEP BY STEP PROCEURE:

STEP 1: (Creation of geometry) Open ETABS Program.

Set the units of the model in the drop down box in the lower right hand

corner of ETABS window , click the drop down box to set units in N. mm.

From Main menu � File � New Model � Select No.

Building Pan Grid System and Storey Data Definition will be displayed. � Uniform Grid Spacing

No. of lines in X Direction =3

No. of lines in Y Direction =4 Spacing in X Direction = 3500 mm

Spacing in y Direction = 4500 mm

� Simple Grid Data No. of stories =5

Typical Storey Height =3000 mm Bottom storey height =2000 mm

Select Grid only button � OK.

Note: You can change Grid spacing by choosing Custom Grid spacing, for

column varying spacing then click Edit Grid you can also change any storey height by choose Custom Storey Data, then click on Edit Storey Data.

Go to Main menu � Edit Storey data � Edit Storey.

Grid No.

Label Height Elevation Master Storey

Similar to Spice point

Spice height

6 Storey 5 3000 14000 Yes No 0

5 Storey 4 3000 11000 No Storey 5 No 0



2 Storey 1 2000 2000 No None No 0

1 Base 0

Change units N.mm.

STEP 2: (Define Material Properties)

From Main menu � Define � Material Property � Add new material �

Material Name =M20 Concrete cubic comp. strength fck =20

Bending Reinforcement yield strength fy =415 Shear Reinforcement yield strength fy =415 � Ok � Ok.

STEP 3: (Define Frame section)

Define Beam:

From Main menu � Define � Frame section � Add rectangular � Material name =M20 (select) � Section Name=B1

Dimensions: Depth (3) =330mm

Width (2) =230mm Click reinforcement

Select � Beam � Concrete cover to rebar center Top = 41 mm (clear cover(25mm)+stirrup dia (8mm)+Dia. Of rod/2 (16/2)

Bottom =41mm � Ok � Ok. In the same manner define other beams B2 and PB.

Define Column:

Add Rectangular � section Name =C1 Material name = M20

Dimensions :

Depth (3) =330mm Width (2) =230mm

Click reinforcement

Select � Column Select � Rectangular

Ties � Rectangular

Cover = 56 mm (clear cover(40mm)+Dia of stirrups(8mm)+Dia. Of rod /2(16/2))

Bar size =16 d Corner bar =16 d

� Reinforcement to be designed � Ok� Ok. In the same manner define column C2 and C3.

Define Slab:

From Main menu � define � Wall/Slab /Deck section � Add New slab �

Section name = S1 Material name = M20.

� Membrane Membrane =125 mm

Bending =125mm

Select � Membrane � Ok � Ok. STEP 5: (Drawing Beams, Columns and Slabs)

Drawing Beams: From Main menu � Draw � Draw line objects � Create lines in region

Property = - Select required beam size B1

Click or Select the beam B1 in Plan view (Left window) (with similar storey option) and select all beam B1.

Change Property = Beam B2 size and click on beam B2 (with Similar storey

option) � Select Plinth beam Property =PB and select all Plinth beams in Storey 1 in plan view (Left Window) with one storey option �Close.

Drawing Columns:

From Main menu � Draw � Draw line objects � Create column in region � Property = C1 �

Select or Click on the column joints in Plan view (Left window) with similar

storey option. If necessary change angle =90 � Change Property =C2 and C3 and click on respective column joints � Close.

Drawing Slab:

From Main menu � Draw � Draw area objects � Create areas at click (Draw

areas) (Plan) � Property =S1 � Click on the periphery of column joints and press enter (With similar storey option).

Note:

To view the assigned beam in plan

Select � Set Building Objects on top of Tool bar.

Select � Line sections under object view options.

� Ok.

To view the rendered view

� Set Building view objects on top of Tool bar

� Line section.

Special Effects:

� Object Fill

� Extrusion

� Apply to all windows � Ok.

STEP 6:(Assigning Support Condition)

Set Base floor Plan view in left window � Set Column points (with mouse) From Main menu � Assign � Joint/Point � Restraints (supports) � Select

Fixed � Ok. To view Support assigned

From top Tool bar � Set Building view option �

Visible in view � Supports � Ok.

Go to Elevation view 1 and view . For other views click � � arrow at top of tool bar.

STEP 7: (Defining Loads) 1.Gravity Loads (Dead Load & Live Load)

From Main menu � Define � Static Load Cases � Load = SDL (Super Imposed Dead Load)

Type = Dead Self weight multiplier =0 � Add New Load � Ok.

Load = Wall Type= Dead

Self weight multiplier =0 � Add New Load � Ok.

Note:

For Self weight multiplier will be 1 for beams and columns of dead load. For all other loads, it will be zero.

Assigning the Loads:

Activate left window and set to Plan view � Activate or select similar storey option (at bottom) and select all slabs

� From Main menu � Assign �

Shell / Area loads � Uniform � Load case name =SDL

� Uniform load Load = 1.50 Kn/m2 (units Kn.m)

Direction Gravity � Ok.

In the same manner assign Load case name = Live � Uniform load

Load = 2.0 Kn/m2 (units Kn.m) Direction Gravity � Ok.

Assigning Wall loads:

9” wall load = 12Kn/m (For external or outer beams) 41/2” wall load=6 Kn/m (For internal beams).

In left side window select all outer beams in top floor by setting similar

storey options and view the status bar to know no. of beams selected � From Main menu � Assign � Frame /Line loads �

Distributed Load case name = wall. Unit Kn.m

� Forces Direction Gravity

Uniform load=12 Kn/m � Replace existing loads � Ok.

In the same manner apply 41/2” wall udl load to internal beams by setting “all floor options”.

To see the load assigned :

Right click the particular member corresponding load � Ok.

Note:

For point load : From Main menu � Assign � Joint/Point loads �

Load case name =Dead. Units Kn.m. � Replace existing loads

Forces Global =10 Kn � Ok.

2. Wind Loads :

In ETABS there are two ways to define lateral loads (Wind, earth quake). Built in option will automatically calculate lateral loads as per available

design codes. Define wind load parameters as per IS 875 --Part 3 (1987)

From Main menu � Define � Static Load cases � Load = X or Y

Type = Wind

Self weight multiplier =0 Auto Lateral load =IS 875—1987 � � Add New Load � Select wind X

load and click on modify lateral loads to specify required wind load parameter. As per IS 875 � Ok � Ok.

Creating dummy areas with property =None

Set required elevation view in right window � From Main menu � Draw

� Draw area objects � Draw rectangular areas � Property = None � Click on the perimeter of area and press enter.

Foot Note: Apply wind load for selections.

To select wind area Main menu � Select � By area object type � select none � Ok.

Assigning wind loads

Select drawing area of required elevation � From Main menu �

Assign � Shell/area loads � Wind Pressure coefficients � Wind load case name =Wind X

Coefficient Cp= - (Change if required) � Ok. To see wind load selection

� Set Building view option �

� Area section

� Line section � Ok.

3.Earthquake Analysis In building, slab is considered as single rigid member during earthquake

analysis. Select left side window.

Select all slabs by setting all floors/ similar storey option � From Main

menu � Define � Diaphragms � Select D1 � Modify/ Show diaphragms � Select � Rigid � Ok � Ok.

Define Mass Source

As per IS 1893-->2002 25% of Live load is considered on all floors of building.

From Main menu � Define � Mass source � select � From Loads �

Load =Dead; Multiplier -->1.0 � Add Load = Live; Multiplier =0.25 � Add

Load =SDL; Multiplier =1.0 � Add Load = Wall; Multiplier =1.0 � Add � Ok.

Define Earthquake Load (Static Method) From Main menu � Define � Static Load cases �

Load =EQX Type = Quake

Default Multiplier =0 Auto Lateral load = IS 1893—2002 � �

Add New Load � Select the load RQX � Modify lateral load � If required

change values as per IS 1893 � Select � X Direction Select � Program calc � per code =0.16 (change as per requirement) �

Ok � Ok.

Assigning Diaphragms

Set all storey option and select all slabs � From Main menu � Assign � Shell area � Diaphragms � D1 � Ok.

To view the Diaphragm

Go to � Set Building View objects

� Diaphragm

STEP 8 : ( Design)

Selecting Indian Code From Main menu � Options � Preferences � Concrete Frame � Design

code = Indian IS 456-2000. � Ok.

Defining Load Combination

From Main menu � Define � Load Combinations � Add New Load Comb �

Load Combination Name =DL+LL

Load Combination type =Add � Change scale factor =1.5 for DL and LL by clicking add button � Add New Load Comb �

Load Combination Name =DL+WL Load Combination type =Add � Change scale factor =1.5 for DL and WL by

clicking add button � Add New Load Comb �

Load Combination Name =DL+EQX Load Combination type =Add � Change scale factor =1.5 for DL and EQX by

clicking add button � Ok � Ok.

Selecting Design Load ( i.e. DL+LL) From Main menu � Design � Concrete Frame design � Select design comb

� Select our combination load from the list � Add � Ok.

STEP 9 : (Analysis)

From Main menu � Analysis � Run analysis. After completing process, the model automatically displaces deformed shape

view and the model is locked (you cannot do any changes ).

STEP 10 : (Running the Design Process)

From Main menu � Design � Concrete frame design � Start Design/ Check of Structure � Design results will be displayed on the model.

Graphical output:

Activate 3D view in right window by clicking title bar � Set elevation view

=1 � From Main menu � Display � Show member force/Stresses diagrams � Frame/Pier/Spandrel forces � Select any load case say DL +LL.

Select moment – 3 option � Uncheck the fill diagram.

If it is checked, we have to deselect. � check the showed values on the

diagram check box � Ok. Right click on any beam in right window which will display diagrams for the

beams. Select � scroll for values (Right top window which will show at different

distances along the beam.

To clear the display: Activate right window � From Main menu � Display � Show un deformed

shape � Click on 3D button from top tool bar to display 3D view.

To view reinforcement detail:

Running the Design Process From Main menu � Design � Concrete Frame Design � start design /Check

of Structure� Design results will be displayed in the model.

Set to Elevation view=1 in right window � Reinforcement area will be

displayed on the frame. Right click on any beam or column. We can select various options:

- Summary - Flexural details

- Shear details etc. - Envelope � Ok.

View the % of steel on beams and columns

From Main menu � Design � Concrete Frame Design � Display design

information � select � Design output=rebar% � Ok.

Example 2 :

No. of stories : 10 No. of bays in X Direction : 4

No. of bays in Y Direction : 5 Spacing in X Direction : 4500


Basement height : 2000 Concrete Grade : M20 for beams & M25 for

Columns Steel Grade : Fy415

Column Sizes C1 : 230 x 460 C2 : 230x 530

C3 : 230x600 Beams B1 : 230x 406

B2 : 230x 380

PB : 230x300 Slab Thickness : 125mm

C2

C2C2C2

C2 C3 C3

C1C3C3C2

C2 C2 C1

C1

C1

FLOOR PLAN

4000 3000 3500

30

00

40

00

28

00

32

00

A B C D

1

2

3

4

5

B2

B2

B2

B2

B1 B1

B1

B2 B2

B2

B1B1

B2 B2 B2

B1 B1 B1

B1 B1

B2

B1

B2

BEAMS:

B1 = 230 X 330

B2 = 230 X 460


COLUMN:

C2 = 230 X 530

C1 = 230 X 460

C3 = 230 X 600

X

Y

TYPICAL STOREY=3000 mmBOTTOM HEIGHT=2000 mm

350030004000

D

44

CB

44

A

STOREY-10

STOREY-9

STOREY-7

STOREY-5

STOREY-3

STOREY-2

STOREY-1

BASE

STEP BY STEP PROCEURE:

STEP 1: (Creation of geometry) Open ETABS Program.

Select units N. mm.


Building Pan Grid System and Storey Data Definition will be displayed.

� Uniform Grid Spacing

No. of lines in X Direction =4 No. of lines in Y Direction =5

Spacing in X Direction = 4000 mm Spacing in y Direction = 3000 mm

� Uniform Grid Spacing Click Edit Grid

X Grid Data

Grid

ID

Ordinate Line type visibility Bubble

location

Grid color

A 0 Primary Show Top

B 4000 Primary Show Top

C 7000 Primary Show Top

D 10500 Primary Show Top

Y Grid data

Grid ID

Ordinate Line type visibility Bubble location

Grid color

1 0 Primary Show Left





� Ok.

Storey dimension: No. of storeys :10

Typical storey height :3000 Bottom storey height :2000

Go to Main menu � Edit � Edit storey data � Edit storey

Level Height Elevation Master

storey

Similar

storey

Splice

point

Splice

height

11 Storey 10 3000 29000 Yes -- No 0









2 Storey 1 2000 2000 No None No 0

1 Base -- 0

� Ok.

Change units N.mm. Select Grid only button � OK.

Note: You can change Grid spacing by choosing Custom Grid spacing, for column varying spacing then click Edit Grid you can also change any storey

height by choose Custom Storey Data, then click on Edit Storey Data.


From Main menu � Define � Material Property � Add new material � Material Name =M25

Concrete cubic comp. strength fck =25

Bending Reinforcement yield strength fy =415 Shear Reinforcement yield strength fy =415 � Ok � Ok.

Similarly Define M20 concrete for beam.

STEP 3: (Define Frame section) Define Beam:

From Main menu � Define � Frame section � Add rectangular � Material name =M20 (select) � Section Name=B1

Dimensions:

Depth (3) =406mm Width (2) =230mm Click reinforcement Select � Beam � Concrete cover to rebar center Top =41 mm

Bottom =41mm � Ok � Ok.

In the same manner define other beams B2 and PB.

Define Column: Add Rectangular � section Name =C1

Material name = M25 Dimensions :

Depth (3) =460mm Width (2) =230mm

Click reinforcement Select � Column Select � Rectangular Ties � Rectangular

Cover = 58 mm Bar size =20 d

Corner bar =20d

� Reinforcement to be designed � Ok� Ok. In the same manner define column C2(230x530) and C3 (230x600).

Define Slab:

From Main menu � define � Wall/Slab /Deck section � Add New slab � Section name = S1

Material name = M20. � Membrane

Membrane =125 mm

Bending =125mm Select � Membrane � Ok � Ok.

STEP 5: (Drawing Beams, Columns and Slabs) Drawing Beams:

From Main menu � Draw � Draw line objects � Create lines in region

Property = - Select required beam size B1

Click or Select the beam B1 in Plan view (Left window) (with similar storey option) and select all beam B1.

Change Property = Beam B2 size and click on beam B2 (with Similar storey option) � Select Plinth beam Property =PB and select all Plinth beams in

Storey 1 in plan view (Left Window) with one storey option �Close.

Drawing Columns: From Main menu � Draw � Draw line objects � Create column in region �

Property = C1 �

Select or Click on the column joints in Plan view (Left window) with similar storey option. If necessary change angle =90 � Change Property =C2 and

C3 and click on respective column joints � Close.

Drawing Slab:

From Main menu � Draw � Draw area objects � Create areas at click (Draw areas) (Plan) � Property =S1 � Click on the periphery of column joints and

press enter (With similar storey option).

Note:




Special effects:

� Object Fill

� Extrusion � Ok.



� Line section.

Special Effects:

� Object Fill

� Extrusion

� Apply to all windows � Ok. STEP 6:(Assigning Support Condition)


Fixed � Ok.

To view Support assigned

From top Tool bar � Set Building view option � Visible in view

� Supports � Ok.

Go to Elevation view 1 and view . For other views click � � arrow at top of tool bar.

STEP 7: (Defining Loads)

1.Gravity Loads (Dead Load & Live Load) From Main menu � Define � Static Load Cases �

Load = SDL (Super Imposed Dead Load)


Load = Wall Type= Dead

Self weight multiplier =0 � Add New Load � Ok.

Assigning the Loads: Activate left window and set to Plan view � Activate or select similar storey

option (at bottom) and select all slabs

� From Main menu � Assign � Shell / Area loads � Uniform �

Load case name =SDL � Uniform load

Load = 1.50 Kn/m2 (units Kn.m)

Direction Gravity � Ok. In the same manner assign Load case name = Live

� Uniform load Load = 2.0 Kn/m2 (units Kn.m)

Direction Gravity � Ok.

Assigning Wall loads:

9” wall load = 12Kn/m (For external or outer beams) 41/2” wall load=6 Kn/m (For internal beams).

In left side window select all outer beams in top floor by setting similar storey options and view the status bar to know no. of beams selected �

From Main menu � Assign � Frame /Line loads � Distributed Load case name = wall. Unit Kn.m

� Forces

Direction Gravity Uniform load=12 Kn/m

� Replace existing loads � Ok. In the same manner apply 41/2” wall udl load to internal beams by setting

“all floor options”.

To see the load assigned : Right click the particular member corresponding load � Ok.

Note: For point load :

From Main menu � Assign � Joint/Point loads � Load case name =Dead. Units Kn.m.

� Replace existing loads Forces Global =10 Kn � Ok.

2. Wind Loads :

Define wind load parameters as per IS 875 --Part 3 (1987) From Main menu � Define � Static Load cases �

Load = X or Y Type = Wind

Self weight multiplier =0 Auto Lateral load =IS 875—1987 � � Add New Load � Select wind X


Creating dummy areas with Property =None. Set required elevation view in right window � From Main menu � Draw

� Draw area objects � Draw rectangular areas � Property = None � Click on the perimeter of area and press enter.




Select drawing area of required elevation � From Main menu � Assign � Shell/area loads � Wind Pressure coefficients � Wind load

case name =Wind X

Coefficient Cp= - (Change if required) � Ok.

To see wind load selection � Set Building view option �

� Area section


3.Earthquake Analysis

Select left side window.



Define Mass Source

As per IS 1893--2002 25% of Live load is considered on all floors of building.


Load =Dead; Multiplier -->1.0 � Add Load = Live; Multiplier =0.25 � Add

Load =SDL; Multiplier =1.0 � Add

Load = Wall; Multiplier =1.0 � Add � Ok.



Default Multiplier =0

Auto Lateral load = IS 1893—2002 � � Add New Load � Select the load RQX � Modify lateral load � If required


Ok � Ok.



To view the Diaphragm Go to � Set Building View objects

� Diaphragm

STEP 8 : ( Design)

Selecting Indian Code

From Main menu � Options � Preferences � Concrete Frame � Design code = Indian IS 456-2000. � Ok.


From Main menu � Define � Load Combinations � Add New Load Comb � Load Combination Name =DL+LL

Load Combination type =Add � Change scale factor =1.5 for DL and LL by

clicking add button � Add New Load Comb � Load Combination Name =DL+WL

Load Combination type =Add � Change scale factor =1.5 for DL and WL by clicking add button � Add New Load Comb �

Load Combination Name =DL+EQX

Load Combination type =Add � Change scale factor =1.5 for DL and EQX by clicking add button � Ok � Ok.

Selecting Design Load ( i.e. DL+LL)

From Main menu � Design � Concrete Frame design � Select design comb


STEP 9 : (Analysis) From Main menu � Analysis � Run analysis.

After completing process, the model automatically displaces deformed shape

view and the model is locked (you cannot do any changes ).

STEP 10 : (Running the Design Process) From Main menu � Design � Concrete frame design � Start Design/

Check of Structure � Design results will be displayed on the model.

Graphical output: Activate 3D view in right window by clicking title bar �

Set elevation view =1 �

From Main menu � Display � Show member force/Stresses diagrams � Frame/Pier/Spandrel forces � Select any load case say DL +LL.

Select moment – 3 option

� Uncheck the fill diagram. If it is checked, we have to deselect. � check the showed values on the




To clear the display:

Activate right window � From Main menu � Display � Show un deformed shape � Click on 3D button from top tool bar to display 3D view.


Running the Design Process

From Main menu � Design � Concrete Frame Design � start design /Check of Structure� Design results will be displayed in the model.


displayed on the frame. Right click on any beam or column. We can select

various options:

- Summary

- Flexural details - Shear details etc.

- Envelope � Ok.

To View the % of steel on beams and columns From Main menu � Design � Concrete Frame Design � Display design

information � select � Design output=rebar% � Ok.

Example 3:

No. of bays in X Direction : 4

No. of bays in Y Direction : 3 Spacing in X Direction : 5000


Basement height : 3200 Concrete Grade : M25

Steel Grade : Fy415 Column Sizes : 300 x 450

Beam : 300x 450

Slab Thickness : 120mm

STEP BY STEP PROCEURE: STEP 1: (Creation of geometry)

Open the ETABS Program.

Set the units of the model in the drop down box in the lower right hand corner of ETABS window , click the drop down box to set units in Kn.m.


Building Pan Grid System and Storey Data Definition will be displayed. � Uniform Grid Spacing

No. of lines in X Direction =5 No. of lines in Y Direction =4

Spacing in X Direction = 5m Spacing in y Direction = 4m

� Simple Grid Data

No. of stories =5

Typical Storey Height =3.2m Bottom storey height =3.2m

Select Grid only button � OK.

Note: You can change Grid spacing by choosing Custom Grid spacing, for column varying spacing then click Edit Grid you can also change any storey

height by choose Custom Storey Data, then click on Edit Storey Data.

Go to Main menu � Edit Storey data � Edit Storey.

Grid No.

Label Height Elevation Master Storey

Similar to Spice point

Spice height

6 Storey 5 3.2 16 Yes No 0

5 Storey 4 3.2 12.6 No Storey 5 No 0



2 Storey 1 3.2 3.2 No None No 0

1 Base 0

Change units N.mm.

STEP 2: (Design Preference code) From Main menu � Options � Preferences � Concrete Frame design

Design code =Indian IS456-2000. �� Ok.


From Main menu � Define � Material Property � Add new material � Material Name =M25

Concrete cubic comp. strength fck =25 Bending Reinforcement yield strength fy =415

Shear Reinforcement yield strength fy =415 � Ok � Ok.

STEP 4: (Define Frame section)

Define Beam: From Main menu � Define � Frame section � Add rectangular � Material

name =M25 (select) � Section Name=B300x450. Dimensions:

Depth (3) =0.45m

Width (2) =0.30m Click reinforcement

Select � Beam � Concrete cover to rebar center Top = 0.041m(=25+8+16/2=41 mm)

Bottom =41mm � Ok � Ok. Define Column:

Add Rectangular � section Name =C300x450.

Material name = M25 Dimensions :

Depth (3) =0.3m Width (2) =0.45m

Click reinforcement

Select � Column Select � Rectangular

Ties � Rectangular

Cover to rebar centre= 0.056 (40+8+16/2=56mm) Bar size =16 d

Corner bar =16 d � Reinforcement to be designed � Ok� Ok.

Define Slab:

From Main menu � define � Wall/Slab /Deck section � Add New slab �

Section name = S1 Material name = M25.

� Membrane Membrane =0.120 m

Bending =0.125m Select � Membrane � Ok � Ok.

STEP 6: (Drawing Beams, Columns and Slabs) Drawing Beams:

From Main menu � Draw � Draw line objects � Create lines in regions or at clicks(plan,Elev.,3D)

Property = - Select required beam size B300x450

Click or Select the beam B300x450 in Plan view (Left window) (with similar storey option) and select all beam B300x450.

�Close.

Drawing Columns:

From Main menu � Draw � Draw line objects � Create column in region or clicks(plan) �

Property = C300x450 �

Select or Click on the column joints in Plan view (Left window) with similar storey option. If necessary change angle =90 � Close.

Drawing Slab:

From Main menu � Draw � Draw area objects � Create areas at click or click (Plan, Elev.) (Plan) � Property =S120 � Click on the periphery of

column joints and press enter (With similar storey option).

Note:




� Ok.



� Line section.

Special Effects:

� Object Fill

� Extrusion

� Apply to all windows � Ok.

STEP 7:(Assigning Support Condition)


Fixed � Ok.

To view Support assigned From top Tool bar � Set Building view option �

Visible in view � Supports � Ok.

Go to Elevation view 1 and view . For other views click � � arrow at top of

tool bar.

STEP 8 : (Defining Loads) 1.Gravity Loads (Dead Load & Live Load)

From Main menu � Define � Static Load Cases � Load = SDL (Super Imposed Dead Load)


Load = Wall

Type= Dead Self weight multiplier =0 � Add New Load � Ok.

Note:

For Self weight multiplier will be 1 for beams and columns of dead load. For all other loads, it will be zero.

Assigning the Loads:

Activate left window and set to Plan view � Activate or select similar storey

option (at bottom) and select all slabs � From Main menu � Assign �

Shell / Area loads � Uniform � Load case name =SDL

� Uniform load


In the same manner assign Load case name = Live � Uniform load


Assigning Wall loads: 9” wall load = 12Kn/m (For external or outer beams)

41/2” wall load=6 Kn/m (For internal beams). In left side window select all outer beams in top floor by setting similar

storey options and view the status bar to know no. of beams selected � From Main menu � Assign � Frame /Line loads �

Distributed Load case name = wall. Unit Kn.m

� Forces Direction Gravity

Uniform load=12 Kn/m � Replace existing loads � Ok.

In the same manner apply 41/2” wall udl load to internal beams by setting “all floor options”.

To see the load assigned :

Right click the particular member corresponding load � Ok.

Note:

For point load : From Main menu � Assign � Joint/Point loads � Forces

Load case name =Dead. Units Kn.m. Forces Global =10 Kn

� Replace existing loads

� Ok.

2. Wind Loads : In ETABS there are two ways to define lateral loads (Wind, earth quake).

Built in option will automatically calculate lateral loads as per available design codes.

Define wind load parameters as per IS 875 --Part 3 (1987) From Main menu � Define � Static Load cases �

Load = X or Y

Type = Wind Self weight multiplier =0

Auto Lateral load =IS 875—1987 � � Add New Load � Select wind X


Creating dummy areas with property =None

Set required elevation view in right window � From Main menu � Draw � Draw area objects � Draw rectangular areas � Property = None �

Click on the perimeter of area and press enter.




Select drawing area of required elevation � From Main menu �

Assign � Shell/area loads � Wind Pressure coefficients � Wind load case name =Wind X

Coefficient Cp= - (Change if required) � Ok.

To see wind load selection � Set Building view option �

� Area section


3. Earthquake Analysis In building, slab is considered as single rigid member during earthquake

analysis. Select left side window.



Define Mass Source

As per IS 1893--2002 25% of Live load is considered on all floors of building.


Load =Dead; Multiplier --1.0 � Add Load = Live; Multiplier =0.25 � Add

Load =SDL; Multiplier =1.0 � Add

Load = Wall; Multiplier =1.0 � Add � Ok.



Default Multiplier =0 Auto Lateral load = IS 1893—2002 � �

Add New Load � Select the load EQX � Modify lateral load � If required


Ok � Ok.



Define Earthquake Load (Response Spectrum or Dynamic method) From Main menu � Define � Response Spectrum Functions � IS 1893 -

2002 � select IS 1893-2002Spectrum � Ok. Select IS1893 �

Modify/Show Spectrum � Spectrum case name =IS1893 Damping =0.05 Modal combination � CQC Directed Combination � SRSS

Function name=1893; Function damping ration=0.05 Seismic zone factor z=0.16 ; Soil type =1 � Ok.

To view the Diaphragm Go to � Set Building View objects

� Diaphragm

STEP 8 : ( Design)

Selecting Indian Code

From Main menu � Options � Preferences � Concrete Frame � Design code = Indian IS 456-2000. � Ok.


From Main menu � Define � Load Combinations � Add New Load Comb � Load Combination Name =DL+LL

Load Combination type =Add � Change scale factor =1.5 for DL and LL by

clicking add button � Add New Load Comb � Load Combination Name =DL+WL

Load Combination type =Add � Change scale factor =1.5 for DL and WL by clicking add button � Add New Load Comb �

Load Combination Name =DL+EQX

Load Combination type =Add � Change scale factor =1.5 for DL and EQX by clicking add button � Ok � Ok.

Selecting Design Load ( i.e. DL+LL)

From Main menu � Design � Concrete Frame design � Select design comb


STEP 9 : (Analysis) From Main menu � Analysis � Run analysis.

After completing process, the model automatically displaces deformed shape view and the model is locked (you cannot do any changes ).

STEP 10 : (Running the Design Process)

From Main menu � Design � Concrete frame design � Start Design/ Check of Structure � Design results will be displayed on the model.

Graphical output:

Activate 3D view in right window by clicking title bar � Set elevation view =1 � From Main menu � Display � Show member force/Stresses diagrams

� Frame/Pier/Spandrel forces � Select any load case say DL +LL.

Select moment – 3 option � Uncheck the fill diagram.

If it is checked, we have to deselect. � check the showed values on the




To clear the display:

Activate right window � From Main menu � Display � Show un deformed shape � Click on 3D button from top tool bar to display 3D view.


Running the Design Process From Main menu � Design � Concrete Frame Design � start design /Check

of Structure� Design results will be displayed in the model.


displayed on the frame. Right click on any beam or column. We can select various options:

- Summary - Flexural details

- Shear details etc. - Envelope � Ok.

View the % of steel on beams and columns From Main menu � Design � Concrete Frame Design � Display design

information � select � Design output=rebar percentage � Ok.

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