V. IS13920 2016-Relative Strength Check
Verify the relative strength of beams and columns at a joint as per clause 7.2 of IS 13920:2016.
Details
Check the relative strength of beams and columns at joint 2 for the two-story structure shown.
The beams on each side of the joint are 400 mm × 400 mm square sections and are 5 m long. The columns above and below the joint are 400 mm × 400 mm square sections and are 3 m tall. The clear cover for both beams and columns is 30 mm on all faces.
Validation
Columns Strength
From Output file , Moment of Resistance based on reinforcement provided for column no. 22 along global X direction (Muz1) = 129.99 kN-m.
From Output file, Moment of Resistance based on reinforcement provided for column no. 1 along global X direction (Muz2) = 149.74 kN-m.
Total Moment of Resistance for column no. 1 and 22 along global X direction
Muz = (Muz1) + (Muz2) = 129.99 + 149.74 = 279.73 KN-m.
From Output file, Moment of Resistance based on reinforcement provided for column no. 22 along global Z direction (Muy1) = 129.99 kN-m.
From Output file, Moment of Resistance based on reinforcement provided for column no. 1 along global Z direction (Muy2) = 149.74 kN-m.
Total Moment of Resistance for column no. 1 and 22 along global Z direction
Muy = (Muy1) + (Muy2) = 129.99 + 149.74 = 279.73 KN-m.
Beams Strength
From output file , Moment of Resistance of Beam no. 2 due to hogging moment at start 55.48 kN-m.
From output file , Moment of Resistance of Beam no. 2 due to sagging moment at start 55.48 kN-m.
From output file , Moment of Resistance of Beam no. 9 due to hogging moment at start 208.14 kN-m.
From output file , Moment of Resistance of Beam no. 9 due to sagging moment at start 117.32 kN-m.
Total Moment of Resistance of Beam at joint no.2 along global X direction
Max {(Beam no.2 hogging moment + Beam no.9 sagging moment),( Beam no.2 sagging moment + Beam no.9 hogging moment)}
Max {( 55.48 + 117.32 ),( 55.48 + 208.14 )} = 263.62 kN-m
.
From output file , Moment of Resistance of Beam no. 4 due to hogging moment at start 55.48 kN-m.
From output file , Moment of Resistance of Beam no. 4 due to sagging moment at start 55.48 kN-m.
Beam is not extended in global (-Z) direction. So, taking zero hogging and sagging moment at global (-Z) direction
Total Moment of Resistance of Beam at joint no.2 along global Z direction
Max {( Beam no.4 hogging moment + 0 ),( Beam no.4 sagging moment + 0)}
= Max {( 55.48 + 0 ),( 55.48 + 0 )} = 55.48 kN-m
Checking Joint status for global X direction
As per Clause 7.2 of IS 13920 : 2016
Total Column Strength at joint no.2 along global X direction should be greater than or equal to 1.4 times Maximum Beam strength at joint no.2 along global X direction
Muz = 279.73 < 1.4 × 263.62 = 369.068
So , the joint no. 2 is falling along global X direction as per Clause 7.2 of IS 13920 : 2016.
Checking Joint status for global Z direction
As per Clause 7.2 of IS 13920 : 2016
Total Column Strength at joint no.2 along global Z direction should be greater than or equal to 1.4 times Maximum Beam strength at joint no.2 along global Z direction
Muy = 279.73 < 1.4 × 55.48 = 77.672
So , the joint no. 2 is passing along global Z direction as per Clause 7.2 of IS 13920 : 2016.
Results
| Result Type | Reference | STAAD.Pro | Difference | Comments |
|---|---|---|---|---|
| Cl. 7.2 check at joint 2, X direction | Fails | Fails ("F") | none | |
| Cl. 7.2 check at joint 2, Z direction | Passes | Passes ("P") | none |
STAAD.Pro Input
The file C:\Users\Public\Public Documents\STAAD.Pro CONNECT Edition\Samples\ Verification Models\10 Concrete Design\India\IS13920 2016-Relative Strength check.STD is typically installed with the program.
STAAD SPACE
START JOB INFORMATION
ENGINEER DATE 13-Aug-20
END JOB INFORMATION
INPUT WIDTH 79
*******************************************************************************
*This Problem is created to verify the clause 7.2 of IS13920 2016 produced by *
*the program *
*Checking Relative Strength of Beam and Column at Joint no.2 * *
*******************************************************************************
UNIT METER KN
JOINT COORDINATES
1 0 2 0; 2 0 5 0; 3 5 5 0; 4 5 2 0; 5 0 2 5; 6 0 5 5; 7 5 5 5; 8 5 2 5;
9 -5 2 0; 10 -5 5 0; 11 -5 2 5; 12 -5 5 5; 13 0 2 10; 14 0 5 10; 15 5 5 10;
16 5 2 10; 17 -5 2 10; 18 -5 5 10; 19 0 8 0; 20 5 8 0; 21 0 8 5; 22 5 8 5;
23 -5 8 0; 24 -5 8 5; 25 0 8 10; 26 5 8 10; 27 -5 8 10;
MEMBER INCIDENCES
1 1 2; 2 2 3; 3 4 3; 4 2 6; 5 3 7; 6 5 6; 7 6 7; 8 8 7; 9 2 10; 10 6 12;
11 9 10; 12 10 12; 13 11 12; 14 6 14; 15 7 15; 16 12 18; 17 13 14; 18 14 15;
19 16 15; 20 14 18; 21 17 18; 22 2 19; 23 3 20; 24 6 21; 25 7 22; 26 10 23;
27 12 24; 28 14 25; 29 15 26; 30 18 27; 31 19 20; 32 19 21; 33 20 22; 34 21 22;
35 19 23; 36 21 24; 37 23 24; 38 21 25; 39 22 26; 40 24 27; 41 25 26; 42 25 27;
DEFINE MATERIAL START
ISOTROPIC CONCRETE
E 2.17185e+07
POISSON 0.17
DENSITY 23.5616
ALPHA 1e-05
DAMP 0.05
TYPE CONCRETE
STRENGTH FCU 30000
G 9.28141e+06
END DEFINE MATERIAL
MEMBER PROPERTY AMERICAN
2 4 5 7 9 10 12 14 TO 16 18 20 31 TO 42 PRIS YD 0.4 ZD 0.4
MEMBER PROPERTY AMERICAN
1 3 8 11 13 22 23 25 TO 27 PRIS YD 0.4 ZD 0.4
MEMBER PROPERTY AMERICAN
6 17 19 24 28 29 PRIS YD 0.5 ZD 0.5
MEMBER PROPERTY
21 30 PRIS YD 0.3 ZD 0.3
CONSTANTS
MATERIAL CONCRETE ALL
SUPPORTS
1 4 5 8 9 11 13 16 17 FIXED
LOAD 1 LOADTYPE Dead TITLE LOAD CASE 1
MEMBER LOAD
2 4 5 7 9 10 12 14 TO 16 18 20 31 TO 42 UNI GY -50
JOINT LOAD
10 12 18 23 24 27 FX 100
2 3 10 19 20 23 FZ 50
6 15 FY 1500
21 26 FY -1500
2 3 10 12 18 FY 300
15 19 20 23 24 27 FY -300
25 FY -500
PERFORM ANALYSIS
PRINT MEMBER FORCES
START CONCRETE DESIGN
CODE IS13920 2016
CLT 0.03 ALL
CLB 0.03 ALL
FC 30000 ALL
FYSEC 415000 ALL
FYMAIN 415000 ALL
MAXMAIN 12 ALL
MINMAIN 12 ALL
GLD 1 ALL
TRACK 9 ALL
TRACK 4
DESIGN BEAM 2 4 5 7 9 10 12 14 TO 16 18 20 31 TO 42
DESIGN COLUMN 1 3 6 8 11 13 17 19 21 TO 30
END CONCRETE DESIGN
FINISH
STAAD.Pro Output
JOINT RELATIVE STRENGTHS OF BEAMS AND COLUMNS AT A JOINT ================================================== COLUMN JOINT CONNECTED COLUMN CONNECTED BEAM STATUS ------- ----- ---------------- -------------------------- ---------- X Z X Z 1 2 22 2 9 4 - F P 3 3 23 2 - 5 - F P 6 6 24 7 10 4 14 F F 8 7 25 7 - 5 15 F F STAAD SPACE -- PAGE NO. 112