# V. AS4100 1998 - Bending Capacity

To check the bending capacity of the UB shape per AS4100-1998.

## Reference

Gorenc,B., R.Tinyou and A.Syam, Steel Designer's Handbook, 8th edition, UNSW Press,

problem 5.3, page 112.

## Problem

Check the suitability of a 360UB50.7 Grade 300 for the beam in Example 5.2 of the reference. This solution relies mainly on AS 4100 and minimally on AISC [1999a], for example, to get basic section properties. Omit deflection checks.

## Comparison

Table 1. Comparison of results
Bending capacity, Mnz (kN·m) 138 137.5 0.3%
Bending moment (kN·m) 125 124.7 0.2%
Utilization ratio 0.906 0.907 0.1%

The reference book does not compute the ratio.

Tip: You can copy and paste this content directly into a .std file to run in STAAD.Pro.

The file C:\Users\Public\Public Documents\STAAD.Pro CONNECT Edition\Samples\ Verification Models\09 Steel Design\Australia\AS4100 1998 - Bending Capacity.STD is typically installed with the program.

``````STAAD PLANE BENDING CAPACITY PER AS4100 1998
*
* REFERENCE : Steel Designer's Handbook, B.Gorenc, R.Tinyou and A.Syam,
*             8th edition, example problem 5.3, page 112
*
*  OBJECTIVE : TO DETERMINE THE ADEQUACY OF A UB SHAPE IN BENDING PER
*              THE AS4100-1998 CODE
*
START JOB INFORMATION
ENGINEER DATE 22-Jul-14
END JOB INFORMATION
*
INPUT WIDTH 79
UNIT METER KN
JOINT COORDINATES
1 0 0 0; 2 8 0 0;
*
MEMBER INCIDENCES
1 1 2;
*
DEFINE MATERIAL START
ISOTROPIC STEEL
E 1.99947e+08
POISSON 0.3
DENSITY 76.8191
ALPHA 6.5e-06
DAMP 0.03
END DEFINE MATERIAL
*
MEMBER PROPERTY AUSTRALIAN
1 TABLE ST UB360X50.7
PRINT MEMBER PROPERTIES ALL
*
CONSTANTS
MATERIAL STEEL ALL
*
SUPPORTS
1 2 PINNED
*******************************
* UB Self weight
1 UNI GY -0.54
* Slab
1 UNI GY -3.328
*
* Imposed Action
1 UNI GY -4.8
1 CON GY -10
*******************************
1 1.2 2 1.5
*******************************
PERFORM ANALYSIS
*
UNIT MMS NEWTON
PARAMETER 1
CODE AUSTRALIAN 1998
*
FYLD 300 ALL
*
* Twist restraint factor
KT 1.04 ALL
*
* Effective length Le
UNT 5820 ALL
*
* Moment modification factor
ALM 1.41 ALL
*
TRACK 2 ALL
CHECK CODE ALL
*
* Published capacity:- Mb = 138 (pg 114)
* Therefore Utilisation ratio = 125/138 = 0.906
*
FINISH
``````

```    *
STAAD.Pro CODE CHECKING - (  AS4100-1998   ) V2.3
****************************************************
NOTE : BY DEFAULT "AS/NZS 3679.1 300" WILL BE USED FOR ROLLED SECTIONS.
|--------------------------------------------------------------------------|
|                                                    Y        PROPERTIES   |
|*************                                       |        IN  CM  UNIT |
|            *  |=============================|   ===|===     ------------ |
|MEMBER   1  *  |  AUSTRALIAN SECTIONS        |      |        AX=0.6470E+2 |
|            *  | ST  UB360X50.7              |      |   --Z  AY=0.2599E+2 |
|DESIGN CODE *  |                             |      |        AZ=0.2622E+2 |
|AS4100 1998 *  ===============================   ===|===     PY=0.1730E+3 |
|            *                                                PZ=0.8970E+3 |
|            *  |&lt;---LENGTH (ME=     8.00 --->|               RY=0.3852E+1 |
|*************                                                RZ=0.1481E+2 |
|                                                             Iw=0.2848E+6 |
|                124.7( KN-METR)                                           |
|PARAMETER        |                   �3                      FORCE/MOMENT |
|IN  NEWTON MM    |               �3      �3                  IN  KN METRE |
|---------------  +                                           -------------|
| KL/R-Y=  207.7  |           �3              �3              PNC=0.2405E+3|
| KL/R-Z=   54.0  +       �3                      �3          PNT=0.1747E+4|
| UNL   = 5820.0  |                                           pn =0.0000E+0|
| MAIN  =  180.0  +                                           MNZ=0.1375E+3|
| PHI   =   0.90  |   �3                              �3      mnz=-.1247E+3|
| FULT  =  440.0  +                                           MNY=0.4547E+2|
| FYLD  =  300.0  |�0                                     �0  mny=0.0000E+0|
| NSF   =   1.00  +---+---+---+---+---+---+---+---+---+---|   VZ =0.6371E+3|
| SKT   =   1.00   -6.9                                       vz =0.0000E+0|
| SKL   =   1.00               ABSOLUTE MZ ENVELOPE           VY =0.3938E+3|
| SKR   =   1.00                  (WITH LOAD NO.)             vy =0.7500E+1|
|                                                                          |
| Section Type:  Compact - about Z axis;     Compact - about Y axis        |
|                                                                          |
|                    Parameters used to calculate RATIO                    |
|                    ----------------------------------                    |
| Ns=0.1723E+4  Msz=0.2691E+3  Msy=0.5053E+2  Mbz=0.1528E+3                |
|               Miz=0.1130E-4  Miy=0.1130E-4  Moz=0.1130E-4                |
|              Nciz=0.1433E+4 Nciy=0.2672E+3  Ncz=0.1433E+4  Ncy=0.2672E+3 |
|              Vvmy=0.4376E+3 Vvmz=0.7079E+3                               |
| ALPHA,M= 1.410  ALPHA,B= 0.000  ALPHA,SZ= 0.403                          |
|                                                                          |
|                      MAX FORCE/ MOMENT SUMMARY ( KN-METR)                |
|                      -------------------------                           |
|                AXIAL      SHEAR-Y    SHEAR-Z    MOMENT-Y    MOMENT-Z     |
|      VALUE       0.0        54.9        0.0         0.0       124.7      |
|   LOCATION       0.0         0.0        0.0         0.0         4.0      |