# V. AISC ASD - Rectangular Tube Compression Capacity

Determine the axial compression capacity of a rectangular 7x5x3/8 structural tube.

## Reference

AISC Allowable Stress Design, 9th Edition, tables on page 3-49.

## Problem

 Fy =46 ksi

 KyLy = KzLz = 25ft

## Comparison

The reported STAAD.Pro value is obtained by multiplying FA times AX from the STAAD.Pro output = 6.32(8.08) = 51.06.

Table 1. Comparison of results
Axial capacity (kips) 51 51.1 <1%

The file C:\Users\Public\Public Documents\STAAD.Pro CONNECT Edition\Samples\ Verification Models\09 Steel Design\US\AISC\AISC ASD - Rectangular Tube Compression Capacity.STD is typically installed with the program.

STAAD SPACE AISC VERIFICATION PROBLEM FOR AXIAL COMPRESSION CAPACITY.
START JOB INFORMATION
ENGINEER DATE 03-Sep-18
END JOB INFORMATION
* PAGE 3-49 OF 9TH ED. AISC-ASD. RECTANGULAR TUBE 7X5X3/8, 25 FT LONG.
* FA SHOULD BE APPROX. 51/8.08 = 6.31 KSI
UNIT FEET KIP
JOINT COORDINATES
1 0 0 0; 2 0 25 0;
MEMBER INCIDENCES
1 1 2;
START USER TABLE
TABLE 1
UNIT INCHES KIP
TUBE
TUB70506
8.08 7 5 0.375 52.2 30.8 64.2 3.97 2.98
END
UNIT INCHES KIP
MEMBER PROPERTY AMERICAN
1 UPTABLE 1 TUB70506
*1 TA ST TUB70506
DEFINE MATERIAL START
ISOTROPIC STEEL_50_KSI
E 29000
POISSON 0.3
DENSITY 0.000283
ALPHA 6.5e-06
DAMP 0.03
TYPE STEEL
STRENGTH FY 50 FU 62 RY 1.5 RT 1.2
END DEFINE MATERIAL
UNIT FEET KIP
CONSTANTS
MATERIAL STEEL_50_KSI ALL
SUPPORTS
1 FIXED
2 FY -50
PERFORM ANALYSIS
UNIT INCHES KIP
PARAMETER 1
CODE AISC
FYLD 46 ALL
TRACK 2 ALL
CHECK CODE ALL
FINISH


                       STAAD.PRO CODE CHECKING - (AISC 9TH EDITION)   v1.0
********************************************
|--------------------------------------------------------------------------|
|                                                    Y        PROPERTIES   |
|*************                                       |        IN INCH UNIT |
|            *  |=============================|   |=====|     ------------ |
|MEMBER   1  *  |            UPT              |   |     |     AX =   8.08  |
|            *  | UP  TUB70506                |   |     |--Z  AY =   3.97  |
|DESIGN CODE *  |                             |   |     |     AZ =   2.98  |
| AISC-1989  *  ===============================   |=====|     SY =  12.32  |
|            *                                                SZ =  14.91  |
|            *  |&lt;---LENGTH (FT)=   25.00 --->|               RY =   1.95  |
|*************                                                RZ =   2.54  |
|                                                                          |
|                  0.0 (KIP-FEET)                                          |
|PARAMETER        |L0 L0  L0  L0  L0  L0  L0  L0  L0  L0  L0  STRESSES     |
|IN KIP  INCH     |L0 L0  L0  L0  L0  L0  L0  L0  L0  L0  L0  IN KIP  INCH |
|---------------  +L0 L0  L0  L0  L0  L0  L0  L0  L0  L0  L0  -------------|
| KL/R-Y= 153.66  |L0 L0  L0  L0  L0  L0  L0  L0  L0  L0  L0  FA  =   6.32 |
| KL/R-Z= 118.03  +L0 L0  L0  L0  L0  L0  L0  L0  L0  L0  L0  fa  =   6.19 |
| UNL   = 300.00  |L0 L0  L0  L0  L0  L0  L0  L0  L0  L0  L0  FCZ =  27.60 |
| CB    =   1.00  +L0 L0  L0  L0  L0  L0  L0  L0  L0  L0  L0  FTZ =  27.60 |
| CMY   =   0.85  |L0 L0  L0  L0  L0  L0  L0  L0  L0  L0  L0  FCY =  27.60 |
| CMZ   =   0.85  +L0 L0  L0  L0  L0  L0  L0  L0  L0  L0  L0  FTY =  27.60 |
| FYLD  =  46.00  |L0 L0  L0  L0  L0  L0  L0  L0  L0  L0  L0  fbz =   0.00 |
| NSF   =   1.00  +---+---+---+---+---+---+---+---+---+---|   fby =   0.00 |
| DFF   =   0.00   0.0                                        Fey =   6.32 |
| dff=      0.00               ABSOLUTE MZ ENVELOPE           Fez =  10.72 |
| (KL/R)max = 153.66              (WITH LOAD NO.)             FV  =  18.40 |
|                                                             fv  =   0.00 |
|                                                                          |
|                      MAX FORCE/ MOMENT SUMMARY  (KIP-FEET)               |
|                      -------------------------                           |
|                                                                          |
|                AXIAL      SHEAR-Y    SHEAR-Z    MOMENT-Y    MOMENT-Z     |
|                                                                          |
|      VALUE      50.0         0.0        0.0         0.0         0.0      |
|   LOCATION       0.0         0.0        0.0         0.0         0.0      |
|                                                                          |
|**************************************************************************|
|*                                                                        *|
|*                         DESIGN SUMMARY  (KIP-FEET)                     *|
|*                         --------------                                 *|
|*                                                                        *|