ETABS Example-r

7/30/2019 ETABS Example-r

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ETABSExtended Three dimensional Analysis for Building S ystem

Example 1:No. of stories : G+3No. of bays in X Direction : 2No. of bays in Y Direction : 3Spacing in X Direction : 3500Spacing in Y Direction : 4500Typical Storey height : 3000Basement height : 2000Concrete Grade : M20Steel Grade : Fy415Column Sizes C1 (Corner Column) : 230 x 300

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

Beams B1 : 230x 330

B2 : 230x 406PB : 230x300Slab Thickness : 125mm


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3500 3500

4 5 0 0

4 5 0 0

4 5 0 0

1

2

3

4

A B C

C2 C1

B1B1

C1

C3C2 C2

B 2

B 2

B 2

B 2

B 2

B 2

C2 C3 C2

C1 C2 C1

B 2

B 2

B 2

B1 B1

B1 B1

B1 B1

BEAMS:

B1 = 230 X 330B2 = 230 X 406

PLINTH BEAM - PB 230 X 300

COLUMN:

C2 = 230 X 380C1 = 230 X 300

C3 = 230 X 460

C3 = 230 X 460

C1 = 230 X 300C2 = 230 X 380

COLUMN:

PLINTH BEAM - PB 230 X 300B2 = 230 X 406B1 = 230 X 330

BEAMS:

2 0 0 0

3 0 0 0

3 0 0 0

3 0 0 0

PB1 PB1

B1B1

B1 B1

B1B1

BASE

STOREY-1

3 0 0 0

STOREY-2

STOREY-3

STOREY-4

STOREY-5

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


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Open ETABS Program.

Set the units of the model in the drop down box in the lower right handcorner 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 =3No. of lines in Y Direction =4Spacing in X Direction = 3500 mmSpacing in y Direction = 4500 mm

Simple Grid DataNo. of stories =5

Typical Storey Height =3000 mm

Bottom storey height =2000 mmSelect Grid only button OK.

Note: You can change Grid spacing by choosing Custom Grid spacing, forcolumn varying spacing then click Edit Grid you can also change any storeyheight by choose Custom Storey Data, then click on Edit Storey Data.

Go to Main menu Edit Storey data Edit Storey.

GridNo.

Label Height Elevation MasterStorey

Similar to Spicepoint

Spiceheight

6 Storey 5 3000 14000 Yes No 05 Storey 4 3000 11000 No Storey 5 No 04 Storey 3 3000 8000 No Storey 5 No 03 Storey 2 3000 5000 No Storey 5 No 02 Storey 1 2000 2000 No None No 01 Base 0

Change units N.mm.

STEP 2: (Define Material Properties)


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From Main menu Define Material Property Add new material Material Name =M20Concrete cubic comp. strength fck =20Bending Reinforcement yield strength fy =415Shear Reinforcement yield strength fy =415 Ok Ok.

STEP 3: (Define Frame section)Define Beam:From Main menu Define Frame section Add rectangular Materialname =M20 (select) Section Name=B1Dimensions:Depth (3) =330mmWidth (2) =230mm

Click reinforcementSelect Beam Concrete cover to rebar center Top =25 mm

Bottom =25mm Ok Ok.In the same manner define other beams B2 and PB.

Define Column:Add Rectangular section Name =C1Material name = M20Dimensions :Depth (3) =330mmWidth (2) =230mm

Click reinforcementSelect Column Select RectangularTies RectangularCover = 40 mmBar size =12 dCorner bar =12 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 = S1Material name = M20.

MembraneMembrane =125 mm

Bending =125mmSelect Membrane Ok Ok.STEP 5: (Drawing Beams, Columns and Slabs)Drawing Beams:


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From Main menu Draw Draw line objects Create lines in regionProperty = -Select required beam size B1Click or Select the beam B1 in Plan view (Left window) (with similar storeyoption) and select all beam B1.Change Property = Beam B2 size and click on beam B2 (with Similar storeyoption) Select Plinth beam Property =PB and select all Plinth beams inStorey 1 in plan view (Left Window) with one storey option Close.

Drawing Columns :From Main menu Draw Draw line objects Create column in regionProperty = C1 Select or Click on the column joints in Plan view (Left window) with similarstorey option. If necessary change angle =90 Change Property =C2 andC3 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.

Special effects:

Object Fill

Extrusion 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)


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Set Base floor Plan view in left window Set Column points (with mouse)From Main menu Assign Joint/Point Restraints (supports) SelectFixed Ok.To view Support assignedFrom 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 = DeadSelf weight multiplier =0 Add New Load Ok.Load = Wall

Type= DeadSelf weight multiplier =0 Add New Load Ok.

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

Assigning the Loads:Activate left window and set to Plan view Activate or select similar storeyoption (at bottom) and select all slabs

From Main menu AssignShell / Area loads UniformLoad case name =SDL

Uniform loadLoad = 1.50 Kn/m 2 (units Kn.m)Direction Gravity Ok.In the same manner assign Load case name = Live

Uniform loadLoad = 2.0 Kn/m 2 (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 similarstorey options and view the status bar to know no. of beams selectedFrom Main menu Assign Frame /Line loads Distributed Load case name = wall. Unit Kn.m

ForcesDirection Gravity


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Uniform load=12 Kn/mReplace 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 loadsForces 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 availabledesign codes.Define wind load parameters as per IS 875 --Part 3 (1987)From Main menu Define Static Load cases Load = X or YType = WindSelf weight multiplier =0Auto Lateral load =IS 8751987 Add New Load Select wind Xload and click on modify lateral loads to specify required wind loadparameter. As per IS 875 Ok Ok.

Creating dummy areas with property =NoneSet 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 coefficientsWind load case name =Wind XCoefficient Cp= - (Change if required) Ok.

To see wind load selectionSet Building view option

Area section Line section Ok.


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3. Earthquake AnalysisIn building, slab is considered as single rigid member during earthquakeanalysis.Select left side window.Select all slabs by setting all floors/ similar storey option From Mainmenu Define Diaphragms Select D1 Modify/ Show diaphragms

Select Rigid Ok Ok.

Define Mass SourceAs 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 AddLoad = Live; Multiplier =0.25 AddLoad =SDL; Multiplier =1.0 AddLoad = Wall; Multiplier =1.0 Add Ok.

Define Earthquake Load (Static Method)From Main menu Define Static Load casesLoad =EQXType = QuakeDefault Multiplier =0Auto Lateral load = IS 18932002 Add New Load Select the load RQX Modify lateral load If requiredchange values as per IS 1893 Select X DirectionSelect Program calc per code =0.16 (change as per requirement) Ok Ok.

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

To view the DiaphragmGo to Set Building View objects

Diaphragm

STEP 8 : ( Design)

Selecting Indian CodeFrom Main menu Options Preferences Concrete Frame Designcode = Indian IS 456-2000. Ok.

Defining Load CombinationFrom Main menu Define Load Combinations Add New Load CombLoad Combination Name =DL+LL


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Load Combination type =Add Change scale factor =1.5 for DL and LL byclicking add button Add New Load Comb Load Combination Name =DL+WLLoad Combination type =Add Change scale factor =1.5 for DL and WL byclicking add button Add New Load CombLoad Combination Name =DL+EQXLoad Combination type =Add Change scale factor =1.5 for DL and EQXby 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 shapeview 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 thediagram check box Ok.Right click on any beam in right window which will display diagrams for thebeams.Select scroll for values (Right top window which will show at differentdistances along the beam.

To clear the display:Activate right window From Main menu Display Show un deformedshape Click on 3D button from top tool bar to display 3D view.To view reinforcement detail:

Running the Design ProcessFrom Main menu Design Concrete Frame Design start design /Checkof Structure Design results will be displayed in the model.

Set to Elevation view=1 in right window Reinforcement area will bedisplayed on the frame. Right click on any beam or column. We can selectvarious options:


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- Summary- Flexural details- Shear details etc.- Envelope Ok.

View the % of steel on beams and columnsFrom Main menu Design Concrete Frame Design Display designinformation select Design output=rebar% Ok.


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Example 2 :No. of stories : 10No. of bays in X Direction : 4No. of bays in Y Direction : 5Spacing in X Direction : 4500Spacing in Y Direction : 3000Typical Storey height : 3000Basement height : 2000Concrete Grade : M20 for beams & M25 for

ColumnsSteel Grade : Fy415Column Sizes C1 : 230 x 460

C2 : 230x 530C3 : 230x600

Beams B1 : 230x 406B2 : 230x 380PB : 230x300

Slab Thickness : 125mm

Y

X

C3 = 230 X 600

C1 = 230 X 460C2 = 230 X 530

COLUMN:


B2 = 230 X 460B1 = 230 X 330

BEAMS:

B2B1

B2

B1B1

B1B1B1

B2B2B2

B1 B1

B2

B2B2

B1

B1B1

B2

B2

B2

B2

5

4

3

2

1

DCB A

3 2 0 0

2

8 0 0

4 0 0 0

3 0 0 0

350030004000

FLOOR PLAN

C1

C1

C1C2C2

C2 C3 C3 C1

C3C3C2

C2 C2 C2

C2


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BASE

STOREY-1

STOREY-2

STOREY-3

STOREY-5

STOREY-7

STOREY-9

STOREY-10

A

4 4

B C

4 4

D

4000 3000 3500

BOTTOM HEIGHT=2000 mmTYPICAL STOREY=3000 mm

STEP BY STEP PROCEURE:


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

Select units N. mm.



No. of lines in X Direction =4No. of lines in Y Direction =5Spacing in X Direction = 4000 mmSpacing in y Direction = 3000 mm

Uniform Grid SpacingClick Edit Grid

X Grid Data

GridID Ordinate Line type visibility Bubblelocation Grid color

A 0 Primary Show TopB 4000 Primary Show TopC 7000 Primary Show TopD 10500 Primary Show Top

Y Grid dataGridID

Ordinate Line type visibility Bubblelocation

Grid color

1 0 Primary Show Left

2 3000 Primary Show Left3 7100 Primary Show Left4 9900 Primary Show Left5 13100 Primary Show Left

Ok.Storey dimension:No. of storeys :10Typical storey height :3000Bottom storey height :2000Go to Main menu Edit Edit storey data Edit storey


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Level Height Elevation Masterstorey

Similarstorey

Splicepoint

Spliceheight

11 Storey 10 3000 29000 Yes -- No 010 Storey 9 3000 26000 No Storey 10 No 09 Storey 8 3000 23000 No Storey 10 No 08 Storey 7 3000 20000 No Storey 10 No 07 Storey 6 3000 17000 No Storey 10 No 06 Storey 5 3000 14000 No Storey 10 No 05 Storey 4 3000 11000 No Storey 10 No 04 Storey 3 3000 8000 No Storey 10 No 03 Storey 2 3000 5000 No Storey 10 No 02 Storey 1 2000 2000 No None No 01 Base -- 0

Ok.

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



From Main menu Define Material Property Add new material Material Name =M25Concrete cubic comp. strength fck =25Bending Reinforcement yield strength fy =415Shear 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 Materialname =M20 (select) Section Name=B1Dimensions:Depth (3) =406mmWidth (2) =230mm

Click reinforcementSelect Beam Concrete cover to rebar center Top =25 mm

Bottom =25mm Ok Ok.In the same manner define other beams B2 and PB.


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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:



Select Line sections under object view options.Special effects:

Object Fill

Extrusion Ok.



Line section.

Special Effects:

Object Fill

Extrusion

Apply to all windows Ok.


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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) SelectFixed Ok.

To view Support assignedFrom top Tool bar Set Building view option Visible in view


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 = WallType= DeadSelf weight multiplier =0 Add New Load Ok.



Uniform loadLoad = 1.50 Kn/m 2 (units Kn.m)Direction Gravity Ok.In the same manner assign Load case name = Live


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 similarstorey options and view the status bar to know no. of beams selectedFrom Main menu Assign Frame /Line loads Distributed Load case name = wall. Unit Kn.m

ForcesDirection GravityUniform load=12 Kn/m

Replace existing loads Ok.


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


Note:For point load :From Main menu Assign Joint/Point loads Load case name =Dead. Units Kn.m.

Replace existing loadsForces 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 = WindSelf weight multiplier =0Auto Lateral load =IS 8751987 Add New Load Select wind Xload and click on modify lateral loads to specify required wind loadparameter. As per IS 875 Ok Ok.

Creating dummy areasProperty =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 areaMain menu Select By area object type select none Ok.

Assigning wind loadsSelect drawing area of required elevation From Main menu Assign Shell/area loads Wind Pressure coefficients Wind loadcase name =Wind X

Coefficient Cp= - (Change if required) Ok.




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3. Earthquake Analysis

Select left side window.Select all slabs by setting all floors/ similar storey option From Mainmenu Define Diaphragms Select D1 Modify/ Show diaphragms

Select Rigid Ok Ok.

Define Mass SourceAs 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 AddLoad = Live; Multiplier =0.25 AddLoad =SDL; Multiplier =1.0 AddLoad = Wall; Multiplier =1.0 Add Ok.

Define Earthquake Load (Static Method)From Main menu Define Static Load casesLoad =EQXType = QuakeDefault Multiplier =0Auto Lateral load = IS 18932002 Add New Load Select the load RQX Modify lateral load If requiredchange values as per IS 1893 Select X DirectionSelect Program calc per code =0.16 (change as per requirement) Ok Ok.

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


Diaphragm

STEP 8 : ( Design)


Defining Load CombinationFrom Main menu Define Load Combinations Add New Load CombLoad Combination Name =DL+LLLoad Combination type =Add Change scale factor =1.5 for DL and LL byclicking add button Add New Load Comb


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Load Combination Name =DL+WLLoad Combination type =Add Change scale factor =1.5 for DL and WL byclicking add button Add New Load CombLoad Combination Name =DL+EQXLoad Combination type =Add Change scale factor =1.5 for DL and EQXby clicking add button Ok Ok.




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 =1From Main menu Display Show member force/Stresses diagrams Frame/Pier/Spandrel forces Select any load case say DL +LL.Select moment 3 option






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- Summary- Flexural details- Shear details etc.- Envelope Ok.

To View the % of steel on beams and columnsFrom Main menu Design Concrete Frame Design Display designinformation select Design output=rebar% Ok.


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Example 3:

No. of bays in X Direction : 4No. of bays in Y Direction : 3Spacing in X Direction : 5000Spacing in Y Direction : 4000Typical Storey height : 3200Basement height : 3200Concrete Grade : M25Steel Grade : Fy415Column Sizes : 300 x 450 Beam : 300x 450 Slab Thickness : 120mm


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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.



No. of lines in X Direction =5No. of lines in Y Direction =4Spacing in X Direction = 5mSpacing in y Direction = 4m

Simple Grid DataNo. of stories =5

Typical Storey Height =3.2mBottom storey height =3.2mSelect Grid only button OK.


Go to Main menu Edit Storey data Edit Storey.

GridNo.

Label Height Elevation MasterStorey

Similar to Spicepoint

Spiceheight

6 Storey 5 3.2 16 Yes No 05 Storey 4 3.2 12.6 No Storey 5 No 04 Storey 3 3.2 9.6 No Storey 5 No 03 Storey 2 3.2 6.4 No Storey 5 No 02 Storey 1 3.2 3.2 No None No 01 Base 0

Change units N.mm.


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STEP 2: (Design Preference code)From Main menu Options Preferences Concrete Frame designDesign code =Indian IS456-2000. Ok.


From Main menu Define Material Property Add new material Material Name =M25Concrete cubic comp. strength fck =25Bending Reinforcement yield strength fy =415Shear 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) =0.45mWidth (2) =0.30m

Click reinforcementSelect 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 = M25Dimensions :Depth (3) =0.3mWidth (2) =0.45m

Click reinforcementSelect Column Select RectangularTies RectangularCover to rebar centre= 0.056 (40+8+16/2=56mm)

Bar size =16 dCorner bar =16 d

Reinforcement to be designed Ok Ok.

Define Slab:From Main menu define Wall/Slab /Deck section Add New slab Section name = S1Material name = M25.

Membrane


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Membrane =0.120 mBending =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 orat clicks(plan,Elev.,3D)Property = -Select required beam size B300x450Click or Select the beam B300x450 in Plan view (Left window) (with similarstorey option) and select all beam B300x450.

Close.

Drawing Columns :From Main menu Draw Draw line objects Create column in region orclicks(plan)

Property = C300x450 Select or Click on the column joints in Plan view (Left window) with similarstorey option. If necessary change angle =90 Close.

Drawing Slab:From Main menu Draw Draw area objects Create areas at click orclick (Plan, Elev.) (Plan) Property =S120 Click on the periphery of column joints and press enter (With similar storey option).

Note:



Select Line sections under object view options.

Special effects:

Object Fill

Extrusion Ok.



Line section.

Special Effects:

Object Fill


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Extrusion

Apply to all windows Ok.

STEP 7:(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 assignedFrom top Tool bar Set Building view option Visible in view


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

From Main menu Define Static Load Cases Load = SDL (Super Imposed Dead Load)Type = DeadSelf weight multiplier =0 Add New Load Ok.Load = WallType= DeadSelf weight multiplier =0 Add New Load Ok.

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




In the same manner assign Load case name = LiveUniform load

Load = 2.0 Kn/m 2 (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).


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In left side window select all outer beams in top floor by setting similarstorey options and view the status bar to know no. of beams selectedFrom Main menu Assign Frame /Line loads Distributed Load case name = wall. Unit Kn.m

ForcesDirection GravityUniform 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.


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

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

Define wind load parameters as per IS 875 --Part 3 (1987)From Main menu Define Static Load cases Load = X or YType = WindSelf weight multiplier =0Auto Lateral load =IS 8751987 Add New Load Select wind Xload and click on modify lateral loads to specify required wind loadparameter. As per IS 875 Ok Ok.

Creating dummy areas with property =NoneSet 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 loadsSelect drawing area of required elevation From Main menu Assign Shell/area loads Wind Pressure coefficients


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Wind load case name =Wind XCoefficient Cp= - (Change if required) Ok.



3. Earthquake AnalysisIn building, slab is considered as single rigid member during earthquakeanalysis.Select left side window.Select all slabs by setting all floors/ similar storey option From Mainmenu 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 AddLoad = Live; Multiplier =0.25 AddLoad =SDL; Multiplier =1.0 AddLoad = Wall; Multiplier =1.0 Add Ok.

Define Earthquake Load (Static Method)From Main menu Define Static Load casesLoad =EQXType = QuakeDefault Multiplier =0Auto Lateral load = IS 18932002 Add New Load Select the load EQX Modify lateral load If requiredchange values as per IS 1893 Select X DirectionSelect Program calc per code =0.16 (change as per requirement) Ok Ok.

Assigning DiaphragmsSet all storey option and select all slabs From Main menu Assign Shell area Diaphragms D1 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 =IS1893Damping =0.05 Modal combination CQC Directed Combination SRSSFunction name=1893; Function damping ration=0.05Seismic zone factor z=0.16 ; Soil type =1 Ok.


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Diaphragm

STEP 8 : ( Design)


Defining Load CombinationFrom Main menu Define Load Combinations Add New Load CombLoad Combination Name =DL+LLLoad Combination type =Add Change scale factor =1.5 for DL and LL byclicking add button Add New Load Comb Load Combination Name =DL+WLLoad Combination type =Add Change scale factor =1.5 for DL and WL by

clicking add button Add New Load CombLoad Combination Name =DL+EQXLoad Combination type =Add Change scale factor =1.5 for DL and EQXby clicking add button Ok Ok.




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



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- Summary- Flexural details

- Shear details etc.- Envelope Ok.

View the % of steel on beams and columnsFrom Main menu Design Concrete Frame Design Display designinformation select Design output=rebar percentage Ok.


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ETABSExtended Three dimensional Analysis for Building S ystem

********

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.


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- 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.

****


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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 notoverlap 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 designinfo.

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 )


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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 Staadfile 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 columnor beam any where we want.

*****


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

o Rigid Panel zone modifier.o Ductile detailing as per IS 13920.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 forplates.

o 3D rendering in ETABS:Go to view menu Select set building view options. In first columnbutton, check Extrusion and object fill.

Disadvantages :ETABS can not generate floor loads. You have to model slabs as plateelement & mesh it and apply floor loads on it.


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4000 3000 3500

3 0 0 0

4 0 0 0

2 8 0 0

3 2 0 0

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

NO. OF FLOORS: 10BEAMS:

B1 = 230 X 330B2 = 230 X 460


COLUMN:

C2 = 230 X 530C1 = 230 X 460

C3 = 230 X 600

FLOOR PLAN UP TO FOURTH STOREY

X

Y

C1

C1 C1 C1

C1C2 C2 C2

C1C2 C3 C3

C3 C3

C2C2C2

C2 C2


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Y

X

C3 = 230 X 600

C1 = 230 X 460C2 = 230 X 530

COLUMN:


B2 = 230 X 460B1 = 230 X 330

BEAMS:

B2

B1

B2

B1B1

B1B1B1

B2B2B2

B1 B1

B2

B2B2

B1

B1B1

B2

B2

B2

B2

5

4

3

2

1

DCB A

3 2 0 0

2 8 0 0

4 0 0 0

3 0 0 0

350030004000

FLOOR PLAN ABOVE FOURTH STOREY

C1

C1

C1C2C2

C2 C3 C3 C1

C3C3C2

C2 C2 C2

C2


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BASE

STOREY-1

STOREY-2

STOREY-3

STOREY-5

STOREY-7

STOREY-9

STOREY-10

A

4 4

B C

4 4

D

4000 3000 3500

BOTTOM HEIGHT=2000 mmTYPICAL STOREY=3000 mm

ETABS Example-r

Documents