EX. US-27 Modeling Soil Springs for a Slab on Grade
This example illustrates the usage of commands necessary to apply the compression only attribute to spring supports for a slab on grade. The spring supports themselves are generated utilizing the built-in support generation facility. The slab is subjected to pressure and overturning loading. A tension/compression only analysis of the structure is performed.
This problem is installed with the program by default to C:\Users\Public\Public Documents\STAAD.Pro 2024\Samples \Sample Models\US\US-27 Modeling Soil Springs for a Slab on Grade.STD when you install the program.
Input File
STAAD SPACE SLAB ON GRADE
* SPRING COMPRESSION EXAMPLE
SET NL 3
UNIT FEET KIP
JOINT COORDINATES
1 0.0 0.0 40.0
2 0.0 0.0 36.0
3 0.0 0.0 28.167
4 0.0 0.0 20.333
5 0.0 0.0 12.5
6 0.0 0.0 6.5
7 0.0 0.0 0.0
REPEAT ALL 3 8.5 0.0 0.0
REPEAT 3 8.0 0.0 0.0
REPEAT 5 6.0 0.0 0.0
REPEAT 3 8.0 0.0 0.0
REPEAT 3 8.5 0.0 0.0
ELEMENT INCIDENCES
1 1 8 9 2 TO 6
REPEAT 16 6 7
UNIT INCH
ELEMENT PROPERTIES
1 TO 102 TH 8.0
DEFINE MATERIAL START
ISOTROPIC CONCRETE
E 4000.0
POISSON 0.12
DENSITY 8.68e-005
ALPHA 5e-006
DAMP 0.05
G 1346.15
TYPE CONCRETE
STRENGTH FCU 4
END DEFINE MATERIAL
CONSTANTS
MATERIAL CONCRETE ALL
SPRING COMPRESSION
1 TO 126 KFY
UNIT FEET
SUPPORTS
1 TO 126 ELASTIC MAT DIRECTION Y SUBGRADE 12.0
LOAD 1 'WEIGHT OF MAT & EARTH'
ELEMENT LOAD
1 TO 102 PR GY -1.50
PERFORM ANALYSIS PRINT STATICS CHECK
CHANGE
LOAD 2 'COLUMN LOAD-DL+LL'
JOINT LOADS
1 2 FY -217.
8 9 FY -109.
5 FY -308.7
6 FY -617.4
22 23 FY -410.
29 30 FY -205.
26 FY -542.7
27 FY -1085.4
43 44 50 51 71 72 78 79 FY -307.5
47 54 82 FY -264.2
48 55 76 83 FY -528.3
92 93 FY -205.0
99 100 FY -410.0
103 FY -487.0
104 FY -974.0
113 114 FY -109.0
120 121 FY -217.0
124 FY -273.3
125 FY -546.6
PERFORM ANALYSIS PRINT STATICS CHECK
CHANGE
LOAD 3 'COLUMN OVERTURNING LOAD'
ELEMENT LOAD
1 TO 102 PR GY -1.50
JOINT LOADS
1 2 FY -100.
8 9 FY -50.
5 FY -150.7
6 FY -310.4
22 23 FY -205.
29 30 FY -102.
26 FY -271.7
27 FY -542.4
43 44 50 51 71 72 78 79 FY -153.5
47 54 82 FY -132.2
48 55 76 83 FY -264.3
92 93 FY 102.0
99 100 FY 205.0
103 FY 243.0
104 FY 487.0
113 114 FY 54.0
120 121 FY 108.0
124 FY 136.3
125 FY 273.6
PERFORM ANALYSIS PRINT STATICS CHECK
LOAD LIST 3
PRINT JOINT DISPLACEMENTS LIST 113 114 120 121
PRINT ELEMENT STRESSES LIST 34 67
PRINT SUPPORT REACTIONS LIST 5 6 12 13
FINISH
PAGE NO. 1
****************************************************
* *
* STAAD.Pro 2023 *
* Version 23.00.03.** *
* Proprietary Program of *
* Bentley Systems, Inc. *
* Date= JUL 4, 2024 *
* Time= 11:27:55 *
* *
* Licensed to: Bentley Systems Inc *
****************************************************
1. STAAD SPACE SLAB ON GRADE
INPUT FILE: D:\Documentation\STAAD.Pro\_Automated_Py\output\2024-07-04\SPro_Output_Input_Files\Sample .. .STD
2. * SPRING COMPRESSION EXAMPLE
3. SET NL 3
4. UNIT FEET KIP
5. JOINT COORDINATES
6. 1 0.0 0.0 40.0
7. 2 0.0 0.0 36.0
8. 3 0.0 0.0 28.167
9. 4 0.0 0.0 20.333
10. 5 0.0 0.0 12.5
11. 6 0.0 0.0 6.5
12. 7 0.0 0.0 0.0
13. REPEAT ALL 3 8.5 0.0 0.0
14. REPEAT 3 8.0 0.0 0.0
15. REPEAT 5 6.0 0.0 0.0
16. REPEAT 3 8.0 0.0 0.0
17. REPEAT 3 8.5 0.0 0.0
18. ELEMENT INCIDENCES
19. 1 1 8 9 2 TO 6
20. REPEAT 16 6 7
21. UNIT INCH
22. ELEMENT PROPERTIES
23. 1 TO 102 TH 8.0
24. DEFINE MATERIAL START
25. ISOTROPIC CONCRETE
26. E 4000.0
27. POISSON 0.12
28. DENSITY 8.68E-005
29. ALPHA 5E-006
30. DAMP 0.05
31. G 1346.15
32. TYPE CONCRETE
33. STRENGTH FCU 4
34. END DEFINE MATERIAL
35. CONSTANTS
36. MATERIAL CONCRETE ALL
37. SPRING COMPRESSION
38. 1 TO 126 KFY
SLAB ON GRADE -- PAGE NO. 2
* SPRING COMPRESSION EXAMPLE
39. UNIT FEET
40. SUPPORTS
41. 1 TO 126 ELASTIC MAT DIRECTION Y SUBGRADE 12.0
42. LOAD 1 'WEIGHT OF MAT & EARTH'
43. ELEMENT LOAD
44. 1 TO 102 PR GY -1.50
45. PERFORM ANALYSIS PRINT STATICS CHECK
P R O B L E M S T A T I S T I C S
-----------------------------------
NUMBER OF JOINTS 126 NUMBER OF MEMBERS 0
NUMBER OF PLATES 102 NUMBER OF SOLIDS 0
NUMBER OF SURFACES 0 NUMBER OF SUPPORTS 126
Using 64-bit analysis engine.
SOLVER USED IS THE IN-CORE ADVANCED MATH SOLVER
TOTAL PRIMARY LOAD CASES = 1, TOTAL DEGREES OF FREEDOM = 378
TOTAL LOAD COMBINATION CASES = 0 SO FAR.
SLAB ON GRADE -- PAGE NO. 3
* SPRING COMPRESSION EXAMPLE
**NOTE-Tension/Compression converged after 1 iterations, Case= 1
STATIC LOAD/REACTION/EQUILIBRIUM SUMMARY FOR CASE NO. 1
'WEIGHT OF MAT & EARTH'
CENTER OF FORCE BASED ON Y FORCES ONLY (FEET).
(FORCES IN NON-GLOBAL DIRECTIONS WILL INVALIDATE RESULTS)
X = 0.645000019E+02
Y = -0.000000000E+00
Z = 0.200000006E+02
TOTAL APPLIED LOAD 1
***TOTAL APPLIED LOAD ( KIP FEET ) SUMMARY (LOADING 1 )
SUMMATION FORCE-X = 0.00
SUMMATION FORCE-Y = -7740.00
SUMMATION FORCE-Z = 0.00
SUMMATION OF MOMENTS AROUND THE ORIGIN-
MX= 154800.01 MY= 0.00 MZ= -499230.03
TOTAL REACTION LOAD 1
***TOTAL REACTION LOAD( KIP FEET ) SUMMARY (LOADING 1 )
SUMMATION FORCE-X = 0.00
SUMMATION FORCE-Y = 7740.00
SUMMATION FORCE-Z = 0.00
SUMMATION OF MOMENTS AROUND THE ORIGIN-
MX= -154800.01 MY= 0.00 MZ= 499230.03
MAXIMUM DISPLACEMENTS ( INCH /RADIANS) (LOADING 1)
MAXIMUMS AT NODE
X = 0.00000E+00 0
Y = -1.50000E+00 1
Z = 0.00000E+00 0
RX= 9.79653E-10 121
RY= 0.00000E+00 0
RZ= 4.32018E-10 45
************ END OF DATA FROM INTERNAL STORAGE ************
46. CHANGE
47. LOAD 2 'COLUMN LOAD-DL+LL'
48. JOINT LOADS
49. 1 2 FY -217.
50. 8 9 FY -109.
51. 5 FY -308.7
52. 6 FY -617.4
53. 22 23 FY -410.
54. 29 30 FY -205.
SLAB ON GRADE -- PAGE NO. 4
* SPRING COMPRESSION EXAMPLE
55. 26 FY -542.7
56. 27 FY -1085.4
57. 43 44 50 51 71 72 78 79 FY -307.5
58. 47 54 82 FY -264.2
59. 48 55 76 83 FY -528.3
60. 92 93 FY -205.0
61. 99 100 FY -410.0
62. 103 FY -487.0
63. 104 FY -974.0
64. 113 114 FY -109.0
65. 120 121 FY -217.0
66. 124 FY -273.3
67. 125 FY -546.6
68. PERFORM ANALYSIS PRINT STATICS CHECK
SLAB ON GRADE -- PAGE NO. 5
* SPRING COMPRESSION EXAMPLE
**NOTE-Tension/Compression converged after 1 iterations, Case= 2
STATIC LOAD/REACTION/EQUILIBRIUM SUMMARY FOR CASE NO. 2
'COLUMN LOAD-DL+LL'
CENTER OF FORCE BASED ON Y FORCES ONLY (FEET).
(FORCES IN NON-GLOBAL DIRECTIONS WILL INVALIDATE RESULTS)
X = 0.633725605E+02
Y = -0.000000000E+00
Z = 0.215722031E+02
TOTAL APPLIED LOAD 2
***TOTAL APPLIED LOAD ( KIP FEET ) SUMMARY (LOADING 2 )
SUMMATION FORCE-X = 0.00
SUMMATION FORCE-Y = -13964.90
SUMMATION FORCE-Z = 0.00
SUMMATION OF MOMENTS AROUND THE ORIGIN-
MX= 301253.66 MY= 0.00 MZ= -884991.47
TOTAL REACTION LOAD 2
***TOTAL REACTION LOAD( KIP FEET ) SUMMARY (LOADING 2 )
SUMMATION FORCE-X = 0.00
SUMMATION FORCE-Y = 13964.90
SUMMATION FORCE-Z = 0.00
SUMMATION OF MOMENTS AROUND THE ORIGIN-
MX= -301253.66 MY= 0.00 MZ= 884991.47
MAXIMUM DISPLACEMENTS ( INCH /RADIANS) (LOADING 2)
MAXIMUMS AT NODE
X = 0.00000E+00 0
Y = -1.12956E+01 120
Z = 0.00000E+00 0
RX= 8.11932E-02 99
RY= 0.00000E+00 0
RZ= 1.00569E-01 6
************ END OF DATA FROM INTERNAL STORAGE ************
69. CHANGE
70. LOAD 3 'COLUMN OVERTURNING LOAD'
71. ELEMENT LOAD
72. 1 TO 102 PR GY -1.50
73. JOINT LOADS
74. 1 2 FY -100.
75. 8 9 FY -50.
76. 5 FY -150.7
77. 6 FY -310.4
SLAB ON GRADE -- PAGE NO. 6
* SPRING COMPRESSION EXAMPLE
78. 22 23 FY -205.
79. 29 30 FY -102.
80. 26 FY -271.7
81. 27 FY -542.4
82. 43 44 50 51 71 72 78 79 FY -153.5
83. 47 54 82 FY -132.2
84. 48 55 76 83 FY -264.3
85. 92 93 FY 102.0
86. 99 100 FY 205.0
87. 103 FY 243.0
88. 104 FY 487.0
89. 113 114 FY 54.0
90. 120 121 FY 108.0
91. 124 FY 136.3
92. 125 FY 273.6
93. PERFORM ANALYSIS PRINT STATICS CHECK
SLAB ON GRADE -- PAGE NO. 7
* SPRING COMPRESSION EXAMPLE
*** LOAD CASE 3 -- START ITERATION NO. 2
*** LOAD CASE 3 -- START ITERATION NO. 3
*** LOAD CASE 3 -- START ITERATION NO. 4
*** LOAD CASE 3 -- START ITERATION NO. 5
**NOTE-Tension/Compression converged after 5 iterations, Case= 3
STATIC LOAD/REACTION/EQUILIBRIUM SUMMARY FOR CASE NO. 3
'COLUMN OVERTURNING LOAD'
CENTER OF FORCE BASED ON Y FORCES ONLY (FEET).
(FORCES IN NON-GLOBAL DIRECTIONS WILL INVALIDATE RESULTS)
X = 0.454460478E+02
Y = -0.000000000E+00
Z = 0.202712741E+02
TOTAL APPLIED LOAD 3
***TOTAL APPLIED LOAD ( KIP FEET ) SUMMARY (LOADING 3 )
SUMMATION FORCE-X = 0.00
SUMMATION FORCE-Y = -10533.10
SUMMATION FORCE-Z = 0.00
SUMMATION OF MOMENTS AROUND THE ORIGIN-
MX= 213519.36 MY= 0.00 MZ= -478687.78
TOTAL REACTION LOAD 3
***TOTAL REACTION LOAD( KIP FEET ) SUMMARY (LOADING 3 )
SUMMATION FORCE-X = 0.00
SUMMATION FORCE-Y = 10533.10
SUMMATION FORCE-Z = 0.00
SUMMATION OF MOMENTS AROUND THE ORIGIN-
MX= -213519.36 MY= 0.00 MZ= 478687.78
MAXIMUM DISPLACEMENTS ( INCH /RADIANS) (LOADING 3)
MAXIMUMS AT NODE
X = 0.00000E+00 0
Y = 3.06386E+01 120
Z = 0.00000E+00 0
RX= -1.35247E-01 120
RY= 0.00000E+00 0
RZ= 1.12342E-01 125
************ END OF DATA FROM INTERNAL STORAGE ************
94. LOAD LIST 3
95. PRINT JOINT DISPLACEMENTS LIST 113 114 120 121
JOINT DISPLACE LIST 113
SLAB ON GRADE -- PAGE NO. 8
* SPRING COMPRESSION EXAMPLE
JOINT DISPLACEMENT (INCH RADIANS) STRUCTURE TYPE = SPACE
------------------
JOINT LOAD X-TRANS Y-TRANS Z-TRANS X-ROTAN Y-ROTAN Z-ROTAN
113 3 0.00000 20.81368 0.00000 -0.10277 0.00000 0.07382
114 3 0.00000 15.82565 0.00000 -0.10134 0.00000 0.06799
120 3 0.00000 30.63862 0.00000 -0.13525 0.00000 0.10711
121 3 0.00000 24.13106 0.00000 -0.12907 0.00000 0.09243
************** END OF LATEST ANALYSIS RESULT **************
96. PRINT ELEMENT STRESSES LIST 34 67
ELEMENT STRESSES LIST 34
SLAB ON GRADE -- PAGE NO. 9
* SPRING COMPRESSION EXAMPLE
ELEMENT STRESSES FORCE,LENGTH UNITS= KIP FEET
----------------
STRESS = FORCE/UNIT WIDTH/THICK, MOMENT = FORCE-LENGTH/UNIT WIDTH
ELEMENT LOAD SQX SQY MX MY MXY
VONT VONB SX SY SXY
TRESCAT TRESCAB
34 3 -4.66 -6.79 2.34 7.95 5.74
164.71 164.71 0.00 0.00 0.00
172.44 172.44
TOP : SMAX= 155.71 SMIN= -16.73 TMAX= 86.22 ANGLE= 58.0
BOTT: SMAX= 16.73 SMIN= -155.71 TMAX= 86.22 ANGLE=-32.0
67 3 32.82 6.55 -63.47 5.72 36.48
1238.45 1238.45 0.00 0.00 0.00
1357.37 1357.37
TOP : SMAX= 288.91 SMIN= -1068.46 TMAX= 678.69 ANGLE= 66.7
BOTT: SMAX= 1068.46 SMIN= -288.91 TMAX= 678.69 ANGLE=-23.3
**** MAXIMUM STRESSES AMONG SELECTED PLATES AND CASES ****
MAXIMUM MINIMUM MAXIMUM MAXIMUM MAXIMUM
PRINCIPAL PRINCIPAL SHEAR VONMISES TRESCA
STRESS STRESS STRESS STRESS STRESS
1.068459E+03 -1.068459E+03 6.786865E+02 1.238454E+03 1.357373E+03
PLATE NO. 67 67 67 67 67
CASE NO. 3 3 3 3 3
********************END OF ELEMENT FORCES********************
97. PRINT SUPPORT REACTIONS LIST 5 6 12 13
SUPPORT REACTION LIST 5
SLAB ON GRADE -- PAGE NO. 10
* SPRING COMPRESSION EXAMPLE
SUPPORT REACTIONS -UNIT KIP FEET STRUCTURE TYPE = SPACE
-----------------
JOINT LOAD FORCE-X FORCE-Y FORCE-Z MOM-X MOM-Y MOM Z
5 3 0.00 149.37 0.00 0.00 0.00 0.00
6 3 0.00 170.57 0.00 0.00 0.00 0.00
12 3 0.00 148.42 0.00 0.00 0.00 0.00
13 3 0.00 152.40 0.00 0.00 0.00 0.00
************** END OF LATEST ANALYSIS RESULT **************
98. FINISH
SLAB ON GRADE -- PAGE NO. 11
* SPRING COMPRESSION EXAMPLE
*********** END OF THE STAAD.Pro RUN ***********
**** DATE= JUL 4,2024 TIME= 11:27:58 ****
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