EX. UK-8 Concrete Design for a Space Frame

In this example, concrete design is performed on some members of a space frame structure. Design calculations consist of computation of reinforcement for beams and columns. Secondary moments on the columns are obtained through the means of a P-Delta analysis.

This problem is installed with the program by default to C:\Users\Public\Public Documents\STAAD.Pro CONNECT Edition\Samples\Sample Models\UK\UK-8 Concrete Design for a Space Frame.STD when you install the program.

Example Problem No. 8

The above example represents a space frame, and the members are made of concrete. The input in the next page will show the dimensions of the members.

Actual input is shown in bold lettering followed by explanation.

```    STAAD SPACE FRAME WITH CONCRETE DESIGN
```

Every input has to start with the term STAAD. The word SPACE signifies that the structure is a space frame structure (3-D) and the geometry is defined through X, Y and Z coordinates.

```    UNIT METER KNS
```

Defines the input units for the data that follows.

```    JOINT COORDINATE
1 0 0 0 ; 2 5.4 0 0 ; 3 11.4 0. 0
4 0 0 7.2 ; 5 5.4 0 7.2 ; 6 11.4 0 7.2
7 0 3.6 0 ; 8 5.4 3.6 0 ; 9 11.4 3.6 0
10 0 3.6 7.2 ; 11 5.4 3.6 7.2 ; 12 11.4 3.6 7.2
13 5.4 7.2 0 ; 14 11.4 7.2 0 ; 15 5.4 7.2 7.2
16 11.4 7.2 7.2
```

Joint number followed by X, Y and Z coordinates are provided above.

Note: Semicolons (;) are used as line separators to allow for input of multiple sets of data on one line.
```    MEMBER INCIDENCE
1 1 7 ; 2 4 10 ; 3 2 8 ; 4 8 13
5 5 11 ; 6 11 15 ; 7 3 9 ; 8 9 14
9 6 12 ; 10 12 16 ; 11 7 8 12
13 10 11 14  ; 15 13 14 ; 16 15 16
17 7 10 ; 18 8 11 ; 19 9 12
20 13 15 ; 21 14 16
```

Defines the members by the joints to which they are connected.

```    UNIT MMS
MEMB PROP
1 2 PRISMATIC YD 300.0 IZ 2.119E08 IY 2.119E08 -
IX 4.237E08
3 TO 10 PR YD 300.0 ZD 300.0 IZ 3.596E08 IY 3.596E08 –
IX 5.324E08
11 TO 21 PR YD 535.0 ZD 380 IZ 2.409E09 IY 1.229E09 –
IX 2.704E09
```

All member properties are provided using the PRISMATIC option. YD and ZD stand for depth and width. If ZD is not provided, a circular shape with diameter = YD is assumed for that cross section. All properties required for the analysis, such as, Area, Moments of Inertia, etc. are calculated automatically from these dimensions unless these are explicitly defined. For this particular example, moments of inertia (IZ, IY) and torsional constant (IX) are provided, so these will not be recalculated. The IX, IY, and IZ values provided in this example are only half the values of a full section to account for the fact that the full moments of inertia will not be effective due to cracking of concrete.

```    DEFINE MATERIAL START
ISOTROPIC CONCRETE
E 21.0
POISSON 0.17
DENSITY 2.356e-008
ALPHA 5e-006
DAMP 0.05
G 9.25
TYPE CONCRETE
STRENGTH FCU 0.0275
END DEFINE MATERIAL
CONSTANTS
MATERIAL CONCRETE ALL
UNIT METER```

The DEFINE MATERIAL command is used to define material properties for concrete. The CONSTANT command is used to assign this to all members.

```    SUPPORT
1 TO 6 FIXED
```

Joints 1 to 6 are fixed supports.

```    LOAD 1 (1.4DL + 1.7LL)
```

Load case 1 is initiated followed by a title.

```    SELF Y -1.4
```

The selfweight of the structure is applied in the global Y direction with a -1.4 factor. Since global Y is vertically upward, the negative factor indicates that this load will act downwards.

```    MEMB LOAD
11 TO 16 UNI Y -42.0
11 TO 16 UNI Y -76.5
```

Load 1 contains member loads also. Y indicates that the load is in the local Y direction. The word UNI stands for uniformly distributed load.

```    LOAD 2 .75 (1.4DL + 1.7LL + 1.7WL)
```

Load case 2 is initiated followed by a title.

```    REPEAT LOAD
1 0.75
```

The preceding command will gather the load data values from load case 1, multiply them with a factor of 0.75 and utilize the resulting values in load 2.

```    JOINT LOAD
15 16 FZ 40.0
11 FZ 90.0
12 FZ 70.0
10 FZ 40.0
```

```    PDELTA ANALYSIS
```

This command instructs the program to proceed with the analysis. The analysis type is P-DELTA indicating that second-order effects are to be calculated.

```    PRINT FORCES LIST 2 5 9 14 16
```

Member end forces are printed using the above PRINT commands. The LIST option restricts the print output to the members listed.

```    START CONCRETE DESIGN
```

The above command initiates a concrete design.

```    CODE BRITISH
TRACK 1.0 MEMB 14
TRACK 2.0 MEMB 16
MAXMAIN 40 ALL
```

The values for the concrete design parameters are defined in the above commands. Design is performed per the BS 8110 Code. The TRACK value dictates the extent of design related information provided in the output. MAXMAIN indicates that the maximum size of main reinforcement is the 40 mm bar. These parameters are described in the manual where British concrete design related information is available.

```    DESIGN BEAM 14 16
```

The above command instructs the program to design beams 14 and 16 for flexure, shear, and torsion.

```    DESIGN COLUMN 2 5
```

The above command instructs the program to design columns 2 and 5 for axial load and biaxial bending.

```    END CONCRETE DESIGN
```

This will end the concrete design.

```    FINISH
```

This command terminates the STAAD run.

Input File

``````STAAD SPACE FRAME WITH CONCRETE DESIGN
UNIT METER KNS
JOINT COORDINATE
1   0.0  0.0  0.0 ;  2   5.4  0.0  0.0
3  11.4  0.0  0.0 ;  4   0.0  0.0  7.2
5   5.4  0.0  7.2 ;  6  11.4  0.0  7.2
7   0.0  3.6  0.0 ;  8   5.4  3.6  0.0
9  11.4  3.6  0.0 ; 10   0.0  3.6  7.2
11  5.4  3.6  7.2 ; 12  11.4  3.6  7.2
13  5.4  7.2  0.0 ; 14  11.4  7.2  0.0
15  5.4  7.2  7.2 ; 16  11.4  7.2  7.2
MEMBER INCIDENCE
1 1 7 ; 2 4 10 ; 3 2 8 ; 4 8 13
5 5 11 ; 6 11 15 ; 7 3 9 ; 8 9 14
9 6 12 ; 10 12 16 ; 11 7 8 12
13 10 11 14 ; 15 13 14 ; 16 15 16
17 7 10 ; 18 8 11 ; 19 9 12
20 13 15 ; 21 14 16
UNIT MMS
MEMB PROP
1 2 PRISMATIC YD 300.0 IZ 2.119E08 IY 2.119E08 -
IX 4.237E08
3 TO 10 PR YD 300.0 ZD 300.0 IZ 3.596E08 IY 3.596E08 -
IX 5.324E08
11 TO 21 PR YD 535.0 ZD 380 IZ 2.409E09 IY 1.229E09 -
IX 2.704E09
DEFINE MATERIAL START
ISOTROPIC CONCRETE
E 21.0
POISSON 0.17
DENSITY 2.356e-008
ALPHA 5e-006
DAMP 0.05
G 9.25
TYPE CONCRETE
STRENGTH FCU 0.0275
END DEFINE MATERIAL
CONSTANTS
MATERIAL CONCRETE ALL
UNIT METER
SUPPORT
1 TO 6 FIXED
SELF Y -1.4
11 TO 16 UNI Y -42.0
11 TO 16 UNI Y -76.5
LOAD 2 .75(1.4DL + 1.7LL + 1.7WL)
1 0.75
15 16 FZ 40.0
11 FZ 90.0
12 FZ 70.0
10 FZ 40.0
PDELTA ANALYSIS
PRINT FORCES LIST 2 5 9 14 16
START CONCRETE DESIGN
CODE BS8007
TRACK 1.0 MEMB 14
TRACK 2.0 MEMB 16
MAXMAIN 40 ALL
DESIGN BEAM 14 16
DESIGN COLUMN 2 5
END CONCRETE DESIGN
FINISH
``````

```                                                                  PAGE NO.    1
****************************************************
*                                                  *
*           Version  22.08.00.***                  *
*           Proprietary Program of                 *
*           Bentley Systems, Inc.                  *
*           Date=    OCT 19, 2021                  *
*           Time=    17:54:33                      *
*                                                  *
*  Licensed to: Bentley Systems Inc                *
****************************************************
1. STAAD SPACE FRAME WITH CONCRETE DESIGN
INPUT FILE: UK-8 Concrete Design for a Space Frame.STD
2. UNIT METER KNS
3. JOINT COORDINATE
4. 1   0.0  0.0  0.0 ;  2   5.4  0.0  0.0
5. 3  11.4  0.0  0.0 ;  4   0.0  0.0  7.2
6. 5   5.4  0.0  7.2 ;  6  11.4  0.0  7.2
7. 7   0.0  3.6  0.0 ;  8   5.4  3.6  0.0
8. 9  11.4  3.6  0.0 ; 10   0.0  3.6  7.2
9. 11  5.4  3.6  7.2 ; 12  11.4  3.6  7.2
10. 13  5.4  7.2  0.0 ; 14  11.4  7.2  0.0
11. 15  5.4  7.2  7.2 ; 16  11.4  7.2  7.2
12. MEMBER INCIDENCE
13. 1 1 7 ; 2 4 10 ; 3 2 8 ; 4 8 13
14. 5 5 11 ; 6 11 15 ; 7 3 9 ; 8 9 14
15. 9 6 12 ; 10 12 16 ; 11 7 8 12
16. 13 10 11 14 ; 15 13 14 ; 16 15 16
17. 17 7 10 ; 18 8 11 ; 19 9 12
18. 20 13 15 ; 21 14 16
19. UNIT MMS
20. MEMB PROP
21. 1 2 PRISMATIC YD 300.0 IZ 2.119E08 IY 2.119E08 -
22. IX 4.237E08
23. 3 TO 10 PR YD 300.0 ZD 300.0 IZ 3.596E08 IY 3.596E08 -
24. IX 5.324E08
25. 11 TO 21 PR YD 535.0 ZD 380 IZ 2.409E09 IY 1.229E09 -
26. IX 2.704E09
27. DEFINE MATERIAL START
28. ISOTROPIC CONCRETE
29. E 21.0
30. POISSON 0.17
31. DENSITY 2.356E-008
32. ALPHA 5E-006
33. DAMP 0.05
34. G 9.25
35. TYPE CONCRETE
36. STRENGTH FCU 0.0275
37. END DEFINE MATERIAL
38. CONSTANTS
FRAME WITH CONCRETE DESIGN                               -- PAGE NO.    2
39. MATERIAL CONCRETE ALL
40. UNIT METER
41. SUPPORT
42. 1 TO 6 FIXED
43. LOAD 1 (1.4DL + 1.7LL)
44. SELF Y -1.4
46. 11 TO 16 UNI Y -42.0
47. 11 TO 16 UNI Y -76.5
48. LOAD 2 .75(1.4DL + 1.7LL + 1.7WL)
50. 1 0.75
52. 15 16 FZ 40.0
53. 11 FZ 90.0
54. 12 FZ 70.0
55. 10 FZ 40.0
56. PDELTA ANALYSIS
P R O B L E M   S T A T I S T I C S
-----------------------------------
NUMBER OF JOINTS         16  NUMBER OF MEMBERS      21
NUMBER OF PLATES          0  NUMBER OF SOLIDS        0
NUMBER OF SURFACES        0  NUMBER OF SUPPORTS      6
Using 64-bit analysis engine.
SOLVER USED IS THE IN-CORE ADVANCED MATH SOLVER
TOTAL      PRIMARY LOAD CASES =     2, TOTAL DEGREES OF FREEDOM =      60
TOTAL LOAD COMBINATION  CASES =     0  SO FAR.
57. PRINT FORCES LIST 2 5 9 14 16
FORCES   LIST     2        5
FRAME WITH CONCRETE DESIGN                               -- PAGE NO.    3
MEMBER END FORCES    STRUCTURE TYPE = SPACE
-----------------
ALL UNITS ARE -- KNS  METE     (LOCAL )
MEMBER  LOAD  JT     AXIAL   SHEAR-Y  SHEAR-Z   TORSION     MOM-Y      MOM-Z
2    1     4    301.86    -18.04    -2.84      0.00      3.49     -23.83
10   -293.46     18.04     2.84     -0.00      6.73     -41.68
2     4    243.90    -14.96   -30.23      1.39     57.98     -20.50
10   -237.60     14.96    30.23     -1.39     57.04     -33.98
5    1     5   1290.04     -2.02    -2.94      0.00      3.79      -5.67
11  -1279.35      2.02     2.94     -0.00      6.82      -4.10
2     5   1015.94     -3.81   -55.16      1.18    121.20      -8.83
11  -1007.92      3.81    55.16     -1.18    111.88      -7.55
9    1     6    758.52     20.05    -2.75     -0.00      3.44      22.20
12   -747.84    -20.05     2.75      0.00      6.48      48.55
2     6    620.14     12.89   -60.00      0.16    124.29      12.18
12   -612.12    -12.89    60.00     -0.16    113.38      32.62
14    1    11    -40.76    435.24     0.00     -0.29     -0.01     498.88
12     40.76    315.99    -0.00      0.29     -0.00    -141.08
2    11    -34.70    327.08     3.02     -1.14    -12.30     375.74
12     34.70    236.34    -3.02      1.14     -5.89    -103.49
16    1    15     60.81    378.36    -0.00      0.04     -0.00     139.84
16    -60.81    372.88     0.00     -0.04      0.00    -123.47
2    15     45.61    283.60     0.40     -0.13     -1.29     104.67
16    -45.61    279.83    -0.40      0.13     -1.01     -93.39
************** END OF LATEST ANALYSIS RESULT **************
58. START CONCRETE DESIGN
CONCRETE DESIGN
59. CODE BS8007
PROGRAM CODE REVISION V1.0_8007_87/1
60. TRACK 1.0 MEMB 14
61. TRACK 2.0 MEMB 16
62. MAXMAIN 40 ALL
63. DESIGN BEAM 14 16
FRAME WITH CONCRETE DESIGN                               -- PAGE NO.    4
====================================================================
B E A M  N O.    14 D E S I G N  R E S U L T S -  FLEXURE
LEN -  6000. mm   FY - 460.  FC - 30.  SIZE -  380. X  535. mm
LEVEL    HEIGHT     BAR INFO       FROM           TO        ANCHOR
mm                       mm            mm       STA  END
-------------------------------------------------------------------
1        35.      5- 20 MM       740.         6000.      NO   YES
|----------------------------------------------------------------|
|   CRITICAL POS MOMENT=    257.51 KN-M   AT  3500. mm, LOAD  1  |
|  REQD STEEL=  1480. mm2, ROW=0.0073, ROWMX=0.0400,ROWMN=0.0013 |
|   MAX/MIN/ACTUAL BAR SPACING=  174./  45./  58. mm             |
|----------------------------------------------------------------|
2       487.      4- 32 MM         0.         1760.      YES  NO
COMP.      5- 10 MM   (REQD. STEEL=    375. SQ. MM)
|----------------------------------------------------------------|
|   CRITICAL NEG MOMENT=    498.88 KN-M   AT     0. mm, LOAD  1  |
|  REQD STEEL=  3192. mm2, ROW=0.0157, ROWMX=0.0400,ROWMN=0.0013 |
|   MAX/MIN/ACTUAL BAR SPACING=  171./  35./  70. mm             |
|----------------------------------------------------------------|
3       497.      7- 12 MM      5240.         6000.      NO   YES
|----------------------------------------------------------------|
|   CRITICAL NEG MOMENT=    141.08 KN-M   AT  6000. mm, LOAD  1  |
|  REQD STEEL=   762. mm2, ROW=0.0037, ROWMX=0.0400,ROWMN=0.0013 |
|   MAX/MIN/ACTUAL BAR SPACING=  170./  37./  41. mm             |
|----------------------------------------------------------------|
B E A M   N O.    14 D E S I G N  R E S U L T S -  SHEAR
|----------------------------------------------------------------|
| FROM -  TO     | MAX. SHEAR | LOAD | LINKS | NO. | SPACING C/C |
|----------------|------------|------|-------|-----|-------------|
| END 1  2001 mm |  435.2  kN |    1 | 8  mm | 28  |   74   mm   |
| 2001   3502 mm |  184.8  kN |    1 | 8  mm |  6  |  250   mm   |
|  3499  5000 mm |  190.8  kN |   1  | 8  mm |  6  |  250   mm   |
|  5000   END 2  |  316.0  kN |    1 | 8  mm | 10  |  111   mm   |
|----------------------------------------------------------------|
FRAME WITH CONCRETE DESIGN                               -- PAGE NO.    5
___  11J____________________ 6000.X 380.X 535_____________________  12J____
|                                                                 =========||
||=====================                            7No12 H*****5240.TO|6000 |
| 4No32 H*****|||0.TO|1760                                        | | | | | |
| 28*8 c/c 74||||||||||                                      10*8 c/c111| | |
|        ||||||||||||||                                           | | | | | |
|        |5No20|H35.00|740.TO 6000                                | | | | | |
|        ==================================================================||
|___________________________________________________________________________|
___________     ___________     ___________     ___________     ___________
|           |   |           |   |           |   |           |   |  ooooooo  |
|   OOOO    |   |   OOOO    |   |           |   |           |   | 7T12      |
| 4T32      |   | 4T32      |   |           |   |           |   |           |
|           |   |           |   |           |   |           |   |           |
|           |   |           |   |           |   |           |   |           |
|           |   | 5T20      |   | 5T20      |   | 5T20      |   | 5T20      |
|           |   |   ooooo   |   |   ooooo   |   |   ooooo   |   |   ooooo   |
|___________|   |___________|   |___________|   |___________|   |___________|
====================================================================
B E A M  N O.    16 D E S I G N  R E S U L T S -  FLEXURE
LEN -  6000. mm   FY - 460.  FC - 30.  SIZE -  380. X  535. mm
LEVEL    HEIGHT     BAR INFO       FROM           TO        ANCHOR
mm                       mm            mm       STA  END
-------------------------------------------------------------------
1        41.      4- 32 MM         0.         6000.      YES  YES
COMP.      6- 8  MM   (REQD. STEEL=    264. SQ. MM)
2       497.      7- 12 MM         0.          760.      YES  NO
3       497.      6- 12 MM      5240.         6000.      NO   YES
REQUIRED REINF. STEEL SUMMARY :
-------------------------------
( MM )         (SQ.  MM )                (KN-METER)
0.          0.0/    754.7         0.00/    139.84        0/  1
500.        264.3/      0.0        34.13/      0.00        1/  0
1000.        971.9/      0.0       176.79/      0.00        1/  0
1500.       1687.4/      0.0       288.09/      0.00        1/  0
2000.       2278.7/      0.0       368.01/      0.00        1/  0
2500.       2684.2/      0.0       416.52/      0.00        1/  0
3000.       2829.9/    264.3       433.60/      0.00        1/  0
3500.       2708.4/      0.0       419.25/      0.00        1/  0
4000.       2322.3/      0.0       373.48/      0.00        1/  0
4500.       1744.6/      0.0       296.29/      0.00        1/  0
5000.       1037.9/      0.0       187.72/      0.00        1/  0
5500.        264.3/      0.0        47.78/      0.00        1/  0
6000.          0.0/    661.2         0.00/    123.47        0/  1
FRAME WITH CONCRETE DESIGN                               -- PAGE NO.    6
B E A M   N O.    16 D E S I G N  R E S U L T S -  SHEAR
|----------------------------------------------------------------|
| FROM -  TO     | MAX. SHEAR | LOAD | LINKS | NO. | SPACING C/C |
|----------------|------------|------|-------|-----|-------------|
| END 1  2001 mm |  378.4  kN |    1 | 8  mm | 28  |   74   mm   |
| 2001   3002 mm |  127.9  kN |    1 | 8  mm |  4  |  250   mm   |
|  2999  4000 mm |  122.5  kN |   1  | 8  mm |  4  |  250   mm   |
|  4000   END 2  |  372.9  kN |    1 | 8  mm | 28  |   74   mm   |
|----------------------------------------------------------------|
___  15J____________________ 6000.X 380.X 535_____________________  16J____
||========                                                        =========||
| 7No12|H*****   0.TO  760                         6No12 H*****5240.TO|6000 |
| ||||||||                                                        ||||||||| |
| 28*8 c/c 74                                                28*8 c/c 74||| |
| ||||||||                                                        ||||||||| |
| 4No32|H41.00   0.TO 6000                                        ||||||||| |
||=========================================================================||
|___________________________________________________________________________|
___________     ___________     ___________     ___________     ___________
|  ooooooo  |   |           |   |           |   |           |   |  oooooo   |
| 7T12      |   |           |   |           |   |           |   | 6T12      |
|           |   |           |   |           |   |           |   |           |
|           |   |           |   |           |   |           |   |           |
|           |   |           |   |           |   |           |   |           |
| 4T32      |   | 4T32      |   | 4T32      |   | 4T32      |   | 4T32      |
|   OOOO    |   |   OOOO    |   |   OOOO    |   |   OOOO    |   |   OOOO    |
|___________|   |___________|   |___________|   |___________|   |___________|
********************END OF BEAM DESIGN**************************
64. DESIGN COLUMN 2 5
FRAME WITH CONCRETE DESIGN                               -- PAGE NO.    7
====================================================================
C O L U M N   N O.      2  D E S I G N   R E S U L T S
FY - 460.  FC - 30. N/MM2   CIRC SIZE   300. MM DIAMETER
AREA OF STEEL REQUIRED =   1681.  SQ. MM.
BAR CONFIGURATION       REINF PCT.   LOAD   LOCATION
----------------------------------------------------
15    12 MM              2.378        2    EACH END
(ARRANGE  COLUMN REINFORCEMENTS SYMMETRICALLY)
====================================================================
C O L U M N   N O.      5  D E S I G N   R E S U L T S
FY - 460.  FC -30. N/MM2   SQRE SIZE -  300. X  300. MM,
AREA OF STEEL REQUIRED =   2677.  SQ. MM.
BAR CONFIGURATION       REINF PCT.   LOAD   LOCATION
----------------------------------------------------
16    16 MM              2.975        2    EACH END
(ARRANGE  COLUMN REINFORCEMENTS SYMMETRICALLY)
********************END OF COLUMN DESIGN RESULTS********************
65. END CONCRETE DESIGN
66. FINISH
*********** END OF THE STAAD.Pro RUN ***********
**** DATE= OCT 19,2021   TIME= 17:54:34 ****
FRAME WITH CONCRETE DESIGN                               -- PAGE NO.    8
************************************************************