EX. US-21 Analysis of a Structure with Tension-Only Members
This example illustrates the modeling of tension-only members using the MEMBER TENSION
command.
This problem is installed with the program by default to C:\Users\Public\Public Documents\STAAD.Pro 2024\Samples \Sample Models\US\US-21 Analysis of a Structure with Tension-Only Members.STD when you install the program.
- L = 15 ft, H = 10 ft
- Load case 1: P1 = 10 kips & P2 = 15 kips
- Load case 2: P3 = -10 kips & P4 = -15 kips
UNIT FEET KIP
Units for the commands to follow are defined above.
JOINT COORDINATES
1 0 0 ; 2 0 10 ; 3 0 20 ; 4 15 20 ; 5 15 10 ; 6 15 0
Joint coordinates of joints 1 to 6 are defined above.
MEMBER PROPERTY AMERICAN
1 TO 10 TA ST W12X26
All members have been assigned a WIDE FLANGE
section from the built in American table.
UNIT INCH
DEFINE MATERIAL START
ISOTROPIC STEEL
E 29000
POISSON 0.3
DENSITY 283e-006
ALPHA 6e-006
DAMP 0.03
TYPE STEEL
STRENGTH FY 36 FU 58 RY 1.5 RT 1.2
END DEFINE MATERIAL
CONSTANT
MATERIAL STEEL ALL
The DEFINE MATERIAL
command is used to specify material properties and the CONSTANT
is used to assign the material to all members. The length units have been changed from feet to inch to facilitate the input of these values.
SUPPORT
1 6 PINNED
The supports are defined above.
MEMBER TENSION
6 TO 9
One or more among the members 6 to 9 may have been inactivated in the analysis.
LOAD 1
JOINT LOAD
2 FX 15
3 FX 10
Load 1 is defined above and consists of joint loads at joints 2 and 3.
LOAD 2
JOINT LOAD
4 FX -10
5 FX -15
Input File
STAAD PLANE EXAMPLE FOR TENSION-ONLY MEMBERS
UNIT FEET KIP
SET NL 3
JOINT COORDINATES
1 0 0 ; 2 0 10 ; 3 0 20 ; 4 15 20 ; 5 15 10 ; 6 15 0
MEMBER INCIDENCES
1 1 2 5
6 1 5 ; 7 2 6 ; 8 2 4 ; 9 3 5 ; 10 2 5
MEMBER TENSION
6 TO 9
MEMBER PROPERTY AMERICAN
1 TO 10 TA ST W12X26
UNIT INCH
DEFINE MATERIAL START
ISOTROPIC STEEL
E 29000.0
POISSON 0.3
DENSITY 283e-006
ALPHA 6e-006
DAMP 0.03
TYPE STEEL
STRENGTH FY 36 FU 58 RY 1.5 RT 1.2
END DEFINE MATERIAL
CONSTANT
MATERIAL STEEL ALL
SUPPORT
1 PINNED
6 PINNED
LOAD 1
JOINT LOAD
2 FX 15
3 FX 10
PERFORM ANALYSIS
CHANGE
MEMBER TENSION
6 TO 9
LOAD 2
JOINT LOAD
4 FX -10
5 FX -15
PERFORM ANALYSIS
CHANGE
MEMBER TENSION
6 TO 9
LOAD 3
REPEAT LOAD
1 1.0 2 1.0
PERFORM ANALYSIS
CHANGE
LOAD LIST ALL
PRINT ANALYSIS RESULTS
FINI
PAGE NO. 1
****************************************************
* *
* STAAD.Pro 2023 *
* Version 23.00.03.** *
* Proprietary Program of *
* Bentley Systems, Inc. *
* Date= JUL 4, 2024 *
* Time= 11:26:37 *
* *
* Licensed to: Bentley Systems Inc *
****************************************************
1. STAAD PLANE EXAMPLE FOR TENSION-ONLY MEMBERS
INPUT FILE: D:\Documentation\STAAD.Pro\_Automated_Py\output\2024-07-04\SPro_Output_Input_Files\Sample .. .STD
2. UNIT FEET KIP
3. SET NL 3
4. JOINT COORDINATES
5. 1 0 0 ; 2 0 10 ; 3 0 20 ; 4 15 20 ; 5 15 10 ; 6 15 0
6. MEMBER INCIDENCES
7. 1 1 2 5
8. 6 1 5 ; 7 2 6 ; 8 2 4 ; 9 3 5 ; 10 2 5
9. MEMBER TENSION
10. 6 TO 9
11. MEMBER PROPERTY AMERICAN
12. 1 TO 10 TA ST W12X26
13. UNIT INCH
14. DEFINE MATERIAL START
15. ISOTROPIC STEEL
16. E 29000.0
17. POISSON 0.3
18. DENSITY 283E-006
19. ALPHA 6E-006
20. DAMP 0.03
21. TYPE STEEL
22. STRENGTH FY 36 FU 58 RY 1.5 RT 1.2
23. END DEFINE MATERIAL
24. CONSTANT
25. MATERIAL STEEL ALL
26. SUPPORT
27. 1 PINNED
28. 6 PINNED
29. LOAD 1
30. JOINT LOAD
31. 2 FX 15
32. 3 FX 10
33. PERFORM ANALYSIS
EXAMPLE FOR TENSION-ONLY MEMBERS -- PAGE NO. 2
P R O B L E M S T A T I S T I C S
-----------------------------------
NUMBER OF JOINTS 6 NUMBER OF MEMBERS 10
NUMBER OF PLATES 0 NUMBER OF SOLIDS 0
NUMBER OF SURFACES 0 NUMBER OF SUPPORTS 2
Using 64-bit analysis engine.
SOLVER USED IS THE IN-CORE ADVANCED MATH SOLVER
TOTAL PRIMARY LOAD CASES = 1, TOTAL DEGREES OF FREEDOM = 14
TOTAL LOAD COMBINATION CASES = 0 SO FAR.
*** LOAD CASE 1 -- START ITERATION NO. 2
**NOTE-Tension/Compression converged after 2 iterations, Case= 1
34. CHANGE
35. MEMBER TENSION
36. 6 TO 9
37. LOAD 2
38. JOINT LOAD
39. 4 FX -10
40. 5 FX -15
41. PERFORM ANALYSIS
*** LOAD CASE 2 -- START ITERATION NO. 2
**NOTE-Tension/Compression converged after 2 iterations, Case= 2
42. CHANGE
43. MEMBER TENSION
44. 6 TO 9
45. LOAD 3
46. REPEAT LOAD
47. 1 1.0 2 1.0
48. PERFORM ANALYSIS
*** LOAD CASE 3 -- START ITERATION NO. 2
**NOTE-Tension/Compression converged after 2 iterations, Case= 3
EXAMPLE FOR TENSION-ONLY MEMBERS -- PAGE NO. 3
49. CHANGE
50. LOAD LIST ALL
51. PRINT ANALYSIS RESULTS
ANALYSIS RESULTS
EXAMPLE FOR TENSION-ONLY MEMBERS -- PAGE NO. 4
JOINT DISPLACEMENT (INCH RADIANS) STRUCTURE TYPE = PLANE
------------------
JOINT LOAD X-TRANS Y-TRANS Z-TRANS X-ROTAN Y-ROTAN Z-ROTAN
1 1 0.00000 0.00000 0.00000 0.00000 0.00000 -0.00062
2 0.00000 0.00000 0.00000 0.00000 0.00000 0.00039
3 0.00000 0.00000 0.00000 0.00000 0.00000 -0.00007
2 1 0.06285 0.00373 0.00000 0.00000 0.00000 -0.00030
2 -0.04313 -0.01262 0.00000 0.00000 0.00000 0.00028
3 0.00605 0.00000 0.00000 0.00000 0.00000 -0.00001
3 1 0.09724 0.00387 0.00000 0.00000 0.00000 -0.00018
2 -0.08929 -0.01613 0.00000 0.00000 0.00000 0.00029
3 0.00408 0.00000 0.00000 0.00000 0.00000 0.00002
4 1 0.08929 -0.01613 0.00000 0.00000 0.00000 -0.00029
2 -0.09724 0.00387 0.00000 0.00000 0.00000 0.00018
3 -0.00408 0.00000 0.00000 0.00000 0.00000 -0.00002
5 1 0.04313 -0.01262 0.00000 0.00000 0.00000 -0.00028
2 -0.06285 0.00373 0.00000 0.00000 0.00000 0.00030
3 -0.00605 0.00000 0.00000 0.00000 0.00000 0.00001
6 1 0.00000 0.00000 0.00000 0.00000 0.00000 -0.00039
2 0.00000 0.00000 0.00000 0.00000 0.00000 0.00062
3 0.00000 0.00000 0.00000 0.00000 0.00000 0.00007
EXAMPLE FOR TENSION-ONLY MEMBERS -- PAGE NO. 5
SUPPORT REACTIONS -UNIT KIP INCH STRUCTURE TYPE = PLANE
-----------------
JOINT LOAD FORCE-X FORCE-Y FORCE-Z MOM-X MOM-Y MOM Z
1 1 -24.91 -23.33 0.00 0.00 0.00 0.00
2 0.09 23.33 0.00 0.00 0.00 0.00
3 -0.05 0.00 0.00 0.00 0.00 0.00
6 1 -0.09 23.33 0.00 0.00 0.00 0.00
2 24.91 -23.33 0.00 0.00 0.00 0.00
3 0.05 0.00 0.00 0.00 0.00 0.00
EXAMPLE FOR TENSION-ONLY MEMBERS -- PAGE NO. 6
MEMBER END FORCES STRUCTURE TYPE = PLANE
-----------------
ALL UNITS ARE -- KIP INCH (LOCAL )
MEMBER LOAD JT AXIAL SHEAR-Y SHEAR-Z TORSION MOM-Y MOM-Z
1 1 1 -6.90 0.26 0.00 0.00 0.00 0.00
2 6.90 -0.26 0.00 0.00 0.00 31.66
2 1 23.33 -0.09 0.00 0.00 0.00 -0.00
2 -23.33 0.09 0.00 0.00 0.00 -10.81
3 1 0.00 0.05 0.00 0.00 0.00 0.00
2 -0.00 -0.05 0.00 0.00 0.00 5.46
2 1 2 -0.24 0.20 0.00 0.00 0.00 6.07
3 0.24 -0.20 0.00 0.00 0.00 18.42
2 2 6.49 -0.43 0.00 0.00 0.00 -25.74
3 -6.49 0.43 0.00 0.00 0.00 -25.59
3 2 0.00 -0.05 0.00 0.00 0.00 -4.66
3 -0.00 0.05 0.00 0.00 0.00 -1.39
3 1 3 9.80 -0.24 0.00 0.00 0.00 -18.42
4 -9.80 0.24 0.00 0.00 0.00 -25.59
2 3 9.80 0.24 0.00 0.00 0.00 25.59
4 -9.80 -0.24 0.00 0.00 0.00 18.42
3 3 10.05 0.00 0.00 0.00 0.00 1.39
4 -10.05 -0.00 0.00 0.00 0.00 -1.39
4 1 4 6.49 0.43 0.00 0.00 0.00 25.59
5 -6.49 -0.43 0.00 0.00 0.00 25.74
2 4 -0.24 -0.20 0.00 0.00 0.00 -18.42
5 0.24 0.20 0.00 0.00 0.00 -6.07
3 4 -0.00 0.05 0.00 0.00 0.00 1.39
5 0.00 -0.05 0.00 0.00 0.00 4.66
5 1 5 23.33 0.09 0.00 0.00 0.00 10.81
6 -23.33 -0.09 0.00 0.00 0.00 0.00
2 5 -6.90 -0.26 0.00 0.00 0.00 -31.66
6 6.90 0.26 0.00 0.00 0.00 0.00
3 5 -0.00 -0.05 0.00 0.00 0.00 -5.46
6 0.00 0.05 0.00 0.00 0.00 0.00
6 1 1 -29.62 0.00 0.00 0.00 0.00 0.00
5 29.62 0.00 0.00 0.00 0.00 0.00
2 1 0.00 0.00 0.00 0.00 0.00 0.00
5 0.00 0.00 0.00 0.00 0.00 0.00
3 1 0.00 0.00 0.00 0.00 0.00 0.00
5 0.00 0.00 0.00 0.00 0.00 0.00
7 1 2 0.00 0.00 0.00 0.00 0.00 0.00
6 0.00 0.00 0.00 0.00 0.00 0.00
EXAMPLE FOR TENSION-ONLY MEMBERS -- PAGE NO. 7
MEMBER END FORCES STRUCTURE TYPE = PLANE
-----------------
ALL UNITS ARE -- KIP INCH (LOCAL )
MEMBER LOAD JT AXIAL SHEAR-Y SHEAR-Z TORSION MOM-Y MOM-Z
2 2 -29.62 0.00 0.00 0.00 0.00 0.00
6 29.62 0.00 0.00 0.00 0.00 0.00
3 2 0.00 0.00 0.00 0.00 0.00 0.00
6 0.00 0.00 0.00 0.00 0.00 0.00
8 1 2 -11.26 0.00 0.00 0.00 0.00 0.00
4 11.26 0.00 0.00 0.00 0.00 0.00
2 2 0.00 0.00 0.00 0.00 0.00 0.00
4 0.00 0.00 0.00 0.00 0.00 0.00
3 2 0.00 0.00 0.00 0.00 0.00 0.00
4 0.00 0.00 0.00 0.00 0.00 0.00
9 1 3 0.00 0.00 0.00 0.00 0.00 0.00
5 0.00 0.00 0.00 0.00 0.00 0.00
2 3 -11.26 0.00 0.00 0.00 0.00 0.00
5 11.26 0.00 0.00 0.00 0.00 0.00
3 3 0.00 0.00 0.00 0.00 0.00 0.00
5 0.00 0.00 0.00 0.00 0.00 0.00
10 1 2 24.31 -0.41 0.00 0.00 0.00 -37.72
5 -24.31 0.41 0.00 0.00 0.00 -36.55
2 2 24.31 0.41 0.00 0.00 0.00 36.55
5 -24.31 -0.41 0.00 0.00 0.00 37.72
3 2 14.90 0.00 0.00 0.00 0.00 -0.79
5 -14.90 -0.00 0.00 0.00 0.00 0.79
************** END OF LATEST ANALYSIS RESULT **************
52. FINI
EXAMPLE FOR TENSION-ONLY MEMBERS -- PAGE NO. 8
*********** END OF THE STAAD.Pro RUN ***********
**** DATE= JUL 4,2024 TIME= 11:26:39 ****
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