STAAD PRO seismic analysis procedure.pdf

SEISMIC ANALYSIS USING LUMPED MASS METHOD

STEPS INVOLVED: 1. Creation of Geometry 2. Giving Member Property 3. Support Condition 4. Giving Loads : Load 1 Dead Load Load 2 Live Load 5. Specifying Analysis Type 6. Post Analysis Print 7. Design 8.  Analysis. (1) In this complete steps steps 1 to 6. Then follow the further steps for Lumped Mass. There are two parts. Part 1 : Finding Joint Loads for Earth quake analysis. Part 2: Applying Earthquake analysis. Before Proceeding take a copy of Model created from step 1 to 6.

Part 1: To find Joint Loads:

1.To give pinned supports at column nodes except base nodes: Main menu

 Select  Beams

parallel to

 Y

Main menu View

 View

selected objects only.

Main menuCommands

Support

specifications

 Pinned  Assign.

2. Apply Load: (1) In Seismic Load for finding joint load we have to consider the following Load case as per Table 8 (Clause 7.3.1 )of IS 1893-2002. 1.0DL+0.25LL (If LL<3KN/m2) 1.0DL+0.50LL Main menu

(If LL>3KN/m2)

Edit Edit

input command file

In Load case below Live Load type the following: Load Combination 3 1 1 2 0.25 Perform Analysis Load List 3 Print Support Reaction (2) Main Menu Analysis (3) Main Menu View

 Run

Analysis

Tables 

Done.

□ Support Reaction.

From support reaction Select only Joint No. and Force FY. Copy and Paste the Joint No. and vertical reaction at the pinned supports in a separate file named as “Joint Load “file.

Type Weight in between Joint No. and Fo rce Fy as below: 16 WEIGHT 81.47 Close the File. Part 2 : Applying Earthquake Analysis: Go to original file of Model created from step 1 to 6. Then follow the steps below: DEFINING SEISMIC LOAD: 1. Main menu 2002

CommandsLoading  

DefinitionsSeismic Load IS1893-

2.Seismic Parameter screen will appear. Select type:IS1893-2002.

□ Include Accidental Load □ Generate . 3. IS1893-2002 Seismic Parameter screen will appear. Select city or Zone. For Zone III Z=0.16 (Table 2 IS1893-2002) Response Reduction Factor (RF) : (Table 7 IS1893-2002) : 5 for SMRF : 3 for OMRF Importance Factor (I)

: (Table 6 IS1893-2002) : 1 for Ordinary Residential Building : 1.5 for Important Building

Other Factors: Rock or Soil sites Factor (SS) : (Clause 6.4.5 of IS1893-2002) : 1 for hard soil (N>30) : 2 for medium soil (10≤ N ≤ 30) for all soils. : 3 for soft soils (N< 10) Type of Structure (ST) (Optional) : (Clause 7.6 IS1893-2002) =1 for RC Frame Building

= 2 for Steel Frame Building = 3 for all other Building Damping Ratio (DM) (Table 3 IS1893-2002): 0.05% PX =Period in X Direction (Optional): PZ =Period in Z Direction (Optional): □ Generate

 Add  Close.

4. Go to “ Joint Load” file .Copy the Joint Weight and apply them as Seismic Weights. For this go to Main menu

Edit Edit

Input Command file.

Below the Zone factor, copy and paste the JOINT WEIGHT as in the Joint Load file.

1. Edit the Load case No.1 (Dead Load) and 2(Live Load) as Load case No. 5 & 6. 2.  APPLYING SEISMIC LOAD: (1) Click Load case details in the Data Area

 Add.

Number: 1 Loading Type: Seismic Tittle : Seismic X +ve Click Load Case 1 Seismic Load

 Add.

 Add

 X

Direction. Factor 1

 Add.  Close.

(2) Click Load case details in the Data Area

 Add.

Number: 2 Loading Type: Seismic Tittle : Seismic X -ve Click Load Case 2 Seismic Load

 Add.

 Add

 X

Direction. Factor:- 1

 Add.  Close.

(3) Click Load case details in the Data Area

 Add.

Number: 3 Loading Type: Seismic Tittle : Seismic Z +ve

 Add.

Click Load Case 1

 Add

Seismic Load

Z Direction. Factor 1



 Add.  Close.

(4) Click Load case details in the Data Area

 Add.

Number: 4 Loading Type: Seismic Tittle : Seismic Z -ve Click Load Case 4 Seismic Load

 Add.

 Add

 Z

Direction. Factor: - 1

LOAD COMBINATION: Main menu

 Load

Combinations

 Add.  Close.

Loading No.7 Name: 1.5(DL+LL) Default: 1.5  Available Load case

Load

Factor

cases 1. EQX+ve

>

5

1.5

2. EQX-ve

>>

6

1.5

3. EQZ+ve

<

4. EQZ-ve

<<

5. DL 6. LL  Add

Loading No.8

Name: 1.5(DL+EQX+ve) Default : 1.5

 Available Load case

Load

Factor

cases 1. EQX+ve

>

5

1.5

2. EQX-ve

>>

1

1.5

3. EQZ+ve

<

4. EQZ-ve

<<

5. DL 6. LL  Add In the similar way add the following load combination. Load case No.

9

10

11

12

13

14

15

16 17

Load case

Factor

5

1.5

2

1.5

5

1.5

3

1.5

5

1.5

4

1.5

5

1.2

6

1.2

1

1.2

5

1.2

6

1.2

2

1.2

5

1.2

6

1.2

3

1.2

5

1.2

6

1.2

4

1.2

5

0.9

1

1.5

5

0.9

18

19

 Add

2

1.5

5

0.9

3

1.5

5

0.9

4

1.5

 Close.

(OR)

AUTO LOAD COMBINATION Main menu

  Commands   Loading Edit

Auto Loads

  Select

Indian

Code Select : New category say EQ No. of rule :4 Rule No.

Dead

Live

Seismic

1

1.5

1.5

--

2

1.5

--

1.5

3

1.2

1.2

1.2

4

0.9

---

1.5

Click Update Table

Close.

Click Load case details

 Add  High

side). Select

: Indian code

light Auto Load Combination (in left

Category:

EQ

 Generate

loadsAdd Close.

Main menuCommandsLoading Load List (selecting Design loads)



Load List. Available Load

Load list

1. EQ X+ve

>

Load Comb

2. EQ X-ve

>>

7 to 19

3. EQ Z+ve

<

4. EQ Z-ve.

<<

5.DL 6.LL 7. 1.5(DL+LL) 8. 1.5(DL+EQX+) 9. 1.5(DL-EQX-) 10. 1.5(DL+EQZ+) 11. 1.5(DL-EQZ-) 12. 1.2(DL+LL+EQX+) 13. 1.2(DL+LL+EQX-) 14. 1.2(DL+LL+EQZ+) 15. 1.2(DL+LL+EQZ-) 16. 0.9DL+1.5 EQX+ 17. 0.9DL+1.5 EQX18. 0.9DL+1.5EQ Z+ 19. 0.9DL+1.5EQ Z-

O.k.  

Close.

STEP 5 ( Analysis ):

From Main menu print

 OK.

 Commands

– Analysis

 Perform

Analysis





No

STEP 6 (Post Analysis Print):

From Main Menu

 Commands  Post

Analysis Print

 Support

Reactions

  To

view

 OK.

STEP 7 ( Design) :

From Main menu code=IS 456

 Commands  Design  Concrete

 From

Main menu

Length =mm; Force = N  Select

all the member

ELY =0.85

 Assign

ELZ =0.85

 Assign

FC

 Assign

=20

FYMAIN= 415 FYSEC =415

MAXSEC

=8

 OK. 

Define parameters

 Assign  Assign

MAXMAIN =16

 Assign

 Assign

MINMAIN =12

 Assign

MINSEC =8 – Assign

 Tools  Set

 Close.

Design

 Current

current input unit

De select all members and select beams only (Main menu Beams

parallel to X and Beam parallel to Z axis)

Select

  Commands

(in

data area) (Concrete Design)

  Design

beam

 Assign 

Deselect all beams and

select columns only(Main menu Select   Beam parallel to Y axis) Design column

 Assign  Take

off

 Assign  Close.

Note: Save the File and Run the Program.

STEP 8 (Analysis):

From Main Menu

 `

Analysis

 Run

Analysis

Select the member and double click on it

 Run

 Shear

Analysis

bending

 Done.

 Close.

