V. AS4600 2018 - C Shear Check

Verify the shear strength of a cold-formed channel along the local z & y directions per the AS6400:2018 code.

Reference

  1. Technical Committee BD-082. Cold-formed steel structures AS/NZS 4600:2018. Sydney, NSW. 2012.

  2. OneSteel Market Mills. Cold Formed Structural Hollow Sections & Profiles. Fourth Edition. 2003. p.46

Problem

A 6 m long, cantilever beam is subjected to an transverse load of 5 kN along the major axis and 10 kN along the minor axis. The section is an Duragal C300X90X8.0 channel. The material is steel with a fy = 400 MPa and fu = 450 MPa.

Section Properties

From reference #2:

  • Depth, d = 300 mm
  • Flange width, bf = 90 mm
  • Thickness, t = 8.0 mm
  • Inside corner radius, ri = 8.0 mm

Calculations

Along Z Direction

Shear force: Vz = 10 kN

Depth of flat portion of web, d1 = bf - tw - ri = 90 - 8.0 - 8.0 = 74 mm

Shear buckling coefficient, kv = 5.34

The slenderness ratio of the web:

The nominal shear capacity per flange (web in the z direction):

(3.3.4.1.)
Vvz = 2×Vvs = 2(151.6) = 303.1 kN

Capacity ratio for shear along minor axis

Along Y Direction

Shear force: Vy = 5 kN

Depth of flat portion of web, d1 = d - 2tw - 2ri = 300 - 2(8.0) - 2(8.0) = 268 mm

Shear buckling coefficient, kv = 5.34

The slenderness ratio of the web:

The nominal shear capacity of the web:

(3.3.4.1.)

Capacity ratio for shear along minor axis

Comparison

Table 1. Comparison of results
Result Type Reference STAAD.Pro Difference Comments
Shear strength along minor axis, ϕVvz (kips) 272.8 272.794 negligible
Ratio for shear along minor axis 0.037 0.0367 negligible
Shear strength along major axis, ϕVvy (kips) 494.0 493.978 negligible
Ratio for shear along major axis 0.010 0.0101 negligible

STAAD.Pro Input File

The file C:\Users\Public\Public Documents\STAAD.Pro 2024\Samples\Verification Models\09 Steel Design\Australia\AS4600 2018 - C Shear Check.STD is typically installed with the program.

The following design parameters are used:

  • The steel yield strength is directly specified: FYLD 400000 and FU 450000
STAAD SPACE
START JOB INFORMATION
ENGINEER DATE 29-June-24
END JOB INFORMATION
INPUT WIDTH 79
UNIT METER KN
JOINT COORDINATES
1 0 0 0; 2 6 0 0;
MEMBER INCIDENCES
1 1 2;
DEFINE MATERIAL START
ISOTROPIC STEEL
E 2.05e+08
POISSON 0.3
DENSITY 76.8195
ALPHA 1.2e-05
DAMP 0.03
G 7.88462e+07
TYPE STEEL
STRENGTH RY 1.5 RT 1.2
END DEFINE MATERIAL
MEMBER PROPERTY 'AUSTRALIA COLD FORMED (ONESTEEL).DB3'
1 TABLE 'CHANNEL - DURAGAL' ST 'C300X90X8.0'
CONSTANTS
MATERIAL STEEL ALL
SUPPORTS
1 FIXED
LOAD 1 LOADTYPE Dead  TITLE LOAD CASE 1
JOINT LOAD
2 FY -5 FZ -10
PERFORM ANALYSIS PRINT ALL
PARAMETER 1
CODE AS NZS 4600 2018
FYLD 400000 ALL
FU 450000 ALL
TRACK 2 ALL
CHECK CODE ALL
FINISH

STAAD.Pro Output

--------------------------------------------------------------------------------
                     ***STAAD.PRO DESIGN RESULTS SUMMARY***
                        Code: AS/NZS 4600:2018 [v1.0]                           
                All units are in kN-m unless otherwise noted                    
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
    MEMBER: 1                     PROFILE: C300X90X8.0                          
   CRITICAL RATIO: 2.272E+1 | STATUS: FAIL | GOVERNING CRITERIA: STRENGTH       
--------------------------------------------------------------------------------
   STRENGTH:                                                                    
   Status: FAIL                 Ratio:   22.7                Loadcase: 1        
   Location: 0.0                Reference: Eq. 3.3.5(1)                         
   Fx: 0.0                      Fy:  -5.00                   Fz:  -10.0         
   Mx: 0.0                      My:   60.0                   Mz:  -30.0         
--------------------------------------------------------------------------------
   SECTION PROPERTIES:                                                          
   Ag:  0.363E-02                                                               
   Ix:  0.774E-07               Iy:  0.244E-05               Iz:  0.442E-04     
   Sy:  0.350E-04               Sz:  0.295E-03               Cw:  0.377E-07     
--------------------------------------------------------------------------------
   SLENDERNESS RATIO:                                                           
   Ratio:   1.16               Actual:  231.425            Allowable:  200.000  
   Ky.Ly/ry:  231.425           Ky:   1.00                   Ly:   6.00         
   Kz.Lz/rz:   54.4             Kz:   1.00                   Lz:   6.00         
--------------------------------------------------------------------------------
   DIMENSIONAL:                                                                 
   Web depth to thickness ratio:                                                
   Ratio:  0.168 [PASS]        Actual:   33.5              Allowable:  200.000  
   Width to thickness ratio:                                                    
   Ratio:  0.154 [PASS]        Actual:   9.25              Allowable:   60.0    
   Unstiffened width to thickness ratio:                                        
   Ratio:  0.154 [PASS]        Actual:   9.25              Allowable:   60.0    
--------------------------------------------------------------------------------
   TENSION:                                                                     
   (Gross Section) Yielding:                                                    
   Ratio: 0.0               Demand: 0.0                 Capacity:   1.31E+03    
   Ref.: Eq. 3.2.1                     LoadCase: 1               Section: 1     
   Intermediate results:                                                        
   Nominal section capacity, Nt:   1.45E+03                                     
   (Net Section) Rupture:                                                       
   Ratio: 0.0               Demand: 0.0                 Capacity:   1.25E+03    
   Ref.: Eq. 3.2.1                     LoadCase: 1               Section: 1     
   Intermediate results:                                                        
   Net area, An:  0.363E-02                                                     
   Nominal section capacity, Nt:   1.39E+03                                     
--------------------------------------------------------------------------------
      STAAD SPACE                                              -- PAGE NO.    6 
--------------------------------------------------------------------------------
                     ***STAAD.PRO DESIGN RESULTS SUMMARY***
                        Code: AS/NZS 4600:2018 [v1.0]                           
                All units are in kN-m unless otherwise noted                    
--------------------------------------------------------------------------------
   ***Contd. Member: 1 | Ratio: 2.272E+1 [F] | Profile: C300X90X8.0             
   COMPRESSION:                                                                 
   Member Capacity:                                                             
   Ratio: 0.0               Demand: 0.0                 Capacity:  102.263      
   Ref.: Cl. 3.4.1                     LoadCase: 1               Section: 1     
   Intermediate results:                                                        
   Nominal member capacity, Nc:  120.309                                        
   Effective area, Ae:  0.363E-02                                               
   Critical stress, fn:   3.31E+04                                              
   Flexural/torsional stress, foc:   3.78E+04                                   
   Section Capacity:                                                            
   Ratio: 0.0               Demand: 0.0                 Capacity:   1.18E+03    
   Ref.: Cl. 3.4.1                     LoadCase: 1               Section: 1     
   Intermediate results:                                                        
   Nominal section capacity, Ns:   1.39E+03                                     
   Effective area, Ae:  0.346E-02                                               
--------------------------------------------------------------------------------
      STAAD SPACE                                              -- PAGE NO.    7 
--------------------------------------------------------------------------------
                     ***STAAD.PRO DESIGN RESULTS SUMMARY***
                        Code: AS/NZS 4600:2018 [v1.0]                           
                All units are in kN-m unless otherwise noted                    
--------------------------------------------------------------------------------
   ***Contd. Member: 1 | Ratio: 2.272E+1 [F] | Profile: C300X90X8.0             
   FLEXURE:                                                                     
   (Local Z) Section Capacity:                                                  
   Ratio:  0.283            Demand:  -30.0              Capacity:  106.006      
   Ref.: Eq. 3.3.1(1)                  LoadCase: 1               Section: 1     
   Intermediate results:                                                        
   Nominal section capacity, Ms:  117.784                                       
   Effective section modulus, Ze:  0.294E-03                                    
   (Local Z) Member Capacity:                                                   
   Ratio:  0.596            Demand:  -30.0              Capacity:   50.3        
   Ref.: Eq. 3.3.1(2)                  LoadCase: 1               Section: 1     
   Intermediate results:                                                        
   Nominal member capacity, Mb:   55.9                                          
   Effective section modulus, Zc:  0.294E-03                                    
   Full unreduced section modulus, Zf:  0.295E-03                               
   Critical moment, Mc:   56.0                                                  
   Moment for section yielding, My:  117.867                                    
   Elastic buckling moment, Mo:   56.0                                          
   (Local Y) Section Capacity:                                                  
   Ratio:   4.77            Demand:   60.0              Capacity:   12.6        
   Ref.: Eq. 3.3.1(1)                  LoadCase: 1               Section: 1     
   Intermediate results:                                                        
   Nominal section capacity, Ms:   14.0                                         
   Effective section modulus, Ze:  0.350E-04                                    
   (Local Y) Member Capacity:                                                   
   Ratio:   1.89            Demand:   60.0              Capacity:   31.7        
   Ref.: Eq. 3.3.1(2)                  LoadCase: 1               Section: 1     
   Intermediate results:                                                        
   Nominal member capacity, Mb:   35.2                                          
   Effective section modulus, Zc:  0.120E-03                                    
   Full unreduced section modulus, Zf:  0.120E-03                               
   Critical moment, Mc:   35.3                                                  
   Moment for section yielding, My:   48.1                                      
   Elastic buckling moment, Mo:   39.5                                          
   Reduced Member Capacity:                                                     
   Ratio:  0.333            Demand:  -30.0              Capacity:   90.1        
   Ref.: Eq. 3.3.1(2)                  LoadCase: 1               Section: 1     
   Intermediate results:                                                        
   Nominal member capacity, Mb:  100.117                                        
   Reduction factor, R:  0.850                                                  
--------------------------------------------------------------------------------
      STAAD SPACE                                              -- PAGE NO.    8 
--------------------------------------------------------------------------------
                     ***STAAD.PRO DESIGN RESULTS SUMMARY***
                        Code: AS/NZS 4600:2018 [v1.0]                           
                All units are in kN-m unless otherwise noted                    
--------------------------------------------------------------------------------
   ***Contd. Member: 1 | Ratio: 2.272E+1 [F] | Profile: C300X90X8.0             
   SHEAR:                                                                       
   (Local Z) Shear Capacity:                                                    
   Ratio:  0.367E-01        Demand:  -10.0              Capacity:  272.794      
   Ref.: Cl. 3.3.4.1                   LoadCase: 1               Section: 1     
   Intermediate results:                                                        
   Nominal shear capacity, Vv:  303.104                                         
   Shear buckling coefficient, kv:   5.34                                       
   Depth of flat portion of web, d1:  0.740E-01                                 
   (Local Y) Shear Capacity:                                                    
   Ratio:  0.101E-01        Demand:  -5.00              Capacity:  493.978      
   Ref.: Cl. 3.3.4.1                   LoadCase: 1               Section: 1     
   Intermediate results:                                                        
   Nominal shear capacity, Vv:  548.864                                         
   Shear buckling coefficient, kv:   5.34                                       
   Depth of flat portion of web, d1:  0.268                                     
--------------------------------------------------------------------------------
   INTERACTION:                                                                 
   Flexure-Shear (Local Z):                                                     
   Ratio:  0.802E-01                                                            
   Ref.: Eq. 3.3.5(1)                  LoadCase: 1               Section: 1     
   Flexure-Shear (Local Y):                                                     
   Ratio:   22.7                                                                
   Ref.: Eq. 3.3.5(1)                  LoadCase: 1               Section: 1     
   Flexure-Tension (Reduced):                                                   
   Ratio:   5.36                                                                
   Ref.: Eq. 3.5.2(1)                  LoadCase: 1               Section: 1     
   Flexure-Tension (Unreduced):                                                 
   Ratio:   5.04                                                                
   Ref.: Eq. 3.5.2(2)                  LoadCase: 1               Section: 1     
   Flexure-Compression (Unreduced):                                             
   Ratio:   5.36                                                                
   Ref.: Eq. 3.5.1(3)                  LoadCase: 1               Section: 1     
--------------------------------------------------------------------------------