V. AISI 2016 2CU F2F Tensile Strength

Verify the axial tensile strength of a double cold-formed channel section according to the AISI S100 2016 specification using both the LRFD and ASD methods.

  1. American Iron and Steel Institute. AISI Manual: Cold-formed Steel Design - Vol. 1.. 2018. Milwaukee, WI.

Details

The member is 10 ft long cantilever. The section used is a pair of 600T125-54 channels in a front-to-front configuration (no spacing between channel toes). Assume a net section area of 0.90× the gross section area.

Section Properties

Properties of a 600T125-54 (listed as a 600CU125-54 in STAAD.Pro):

  • Cross-section area, A = 0.48 in2

Material Properties

  • E = 29,000 ksi
  • G = 11,200 ksi
  • Fy = 36 ksi
  • Fu = 58 ksi

Calculations

Section Properties

  • Cross-section area, A = 2× 0.48 = 0.96 in2

The net area of the cross section:

An = 0.9× (0.96) = 0.864 in2

Tensile Yielding of Gross Section

Tn = Ag×Fy = 0.96 × 36 = 34.56
((Eq. D2-1))
  • LRFD: ϕtTn = 0.90 × 34.56 = 31.10 kips
  • ASD: Tnt = 34.56 / 1.67 = 20.69 kips

Tensile Rupture of Net Section

Tn = An×Fy = 0.864 × 58 = 50.11
((Eq. D3-1))
  • LRFD: ϕtTn = 0.75 × 50.11 = 37.58 kips
  • ASD: Tnt = 50.11 / 2.00 = 25.06 kips

Comparison

Table 1. Comparison of results
Result Type Reference STAAD.Pro Difference Comments
LRFD Tensile Yielding of Gross Section, ϕtTn , (kN) 31.10 31.104 negligible
Tensile Rupture of Net Section, ϕtTn , (kN) 37.58 37.584 negligible
ASD Tensile Yielding of Gross Section, Tnt , (kN) 20.69 20.695 negligible
Tensile Rupture of Net Section, Tnt , (kN) 25.06 25.056 negligible

STAAD Input

The file C:\Users\Public\Public Documents\STAAD.Pro 2024\Samples \Verification Models\09 Steel Design\US\AISI\AISI 2016 2CU F2F Tensile Strength.STD is typically installed with the program.

The following design parameters are used:
  • The net section factor is specified using the NSF 0.9 parameter.
  • Unreinforced webs are specified using the TSA 0 parameter.
STAAD SPACE
START JOB INFORMATION
ENGINEER DATE 11-Jan-22
ENGINEER NAME TK
END JOB INFORMATION
INPUT WIDTH 79
UNIT FEET KIP
JOINT COORDINATES
1 0 0 0; 2 10 0 0;
MEMBER INCIDENCES
1 1 2;
DEFINE MATERIAL START
ISOTROPIC STEEL
E 4.176e+06
POISSON 0.3
DENSITY 0.489024
ALPHA 6.5e-06
DAMP 0.03
G 1.6128e+06
TYPE STEEL
STRENGTH RY 1.5 RT 1.2
END DEFINE MATERIAL
UNIT INCHES KIP
MEMBER PROPERTY COLDFORMED AMERICAN
1 TABLE FR 600CU125-54
CONSTANTS
MATERIAL STEEL ALL
SUPPORTS
1 FIXED
LOAD 1 LOADTYPE None  TITLE LOAD CASE 1
JOINT LOAD
2 FX 10
PERFORM ANALYSIS
PARAMETER 1
CODE AISI 2016
METHOD LRFD
FYLD 36 ALL
FU 58 ALL
FLX 0 ALL
NSF 0.9 ALL
TSA 0 ALL
TRACK 2 ALL
CHECK CODE ALL
PARAMETER 2
CODE AISI 2016
METHOD ASD
FYLD 36 ALL
FU 58 ALL
FLX 0 ALL
NSF 0.9 ALL
TSA 0 ALL
TRACK 2 ALL
CHECK CODE ALL
FINISH

STAAD Output

            STAAD.Pro CODE CHECKING - (AISI S100-16) [LRFD] (v1.0)
           ********************************************************
ALL UNITS ARE IN "INCH" AND "KIP " (U.N.O.)
|-----------------------------------------------------------------------------|
|  MEMBER:     1     SECTION:FR  600CU125-54     LEN:  120.000     LOC:   0.000 |
| STATUS: PASS       RATIO:  0.322             REF: Sec. D2       LC:      1  |
|-----------------------------------------------------------------------------|
| DESIGN FORCES:                                                              |
|  Location:    0.000  Criteria:   Sec. D2              LC:           1       |
|  Fx:(T)      -10.000       Fy:        -0.000          Fz:      -0.000       |
|  Mx:           0.000       My:        -0.000          Mz:      -0.000       |
|-----------------------------------------------------------------------------|
| SECTION PROPERTIES:                                                         |
|  Ag:         0.96000       Az:     0.25096            Ay:     0.66958       |
|  Cz:         0.20400       Cy:     3.09900                                  |
|  Iz:         4.68000       Iy:     1.15815             J:     0.00104       |
|  Sz:         1.51016       Sy:     0.92652                                  |
|  Rz:         2.20794       Ry:     1.09837            Cw:     0.00000       |
|-----------------------------------------------------------------------------|
| MATERIAL INFO:                                                              |
|  Fy:    36.000        Fu:    58.000      E:  29000.000       G:  11200.000  |
|-----------------------------------------------------------------------------|
| DESIGN PROPERTIES:                                                          |
|  Member Length:   120.000   Lz:   120.000   Ly:   120.000   Lb:       0.000 |
| DESIGN PARAMETERS:                                                          |
|  Kz:   1.000    Ky:   1.000    NSF:  0.900                                  |
|-----------------------------------------------------------------------------|
| CRITICAL SLENDERNESS:                                                       |
|-----------------------------------------------------------------------------|
|  LC :     1   Actual :  109.253   Allowable :  300.000   Ratio :   0.364    |
|-----------------------------------------------------------------------------|
|  Section Dimension Check      |    Ratio     |    Limit     |     Status    |
|-----------------------------------------------------------------------------|
|  Radius To Thickness Ratio    |      1.500   |     10.000   |      PASS     |
|  Width To Thickness Ratio     |     17.085   |    500.000   |      PASS     |
|  Web Depth To Thickness Ratio |    104.505   |    200.000   |      PASS     |
|-----------------------------------------------------------------------------|
      STAAD SPACE                                              -- PAGE NO.    4 
            STAAD.Pro CODE CHECKING - (AISI S100-16) [LRFD] (v1.0)
           ********************************************************
ALL UNITS ARE IN "INCH" AND "KIP " (U.N.O.)
|                                              - MEMBER:       1 (Contd.....) |
|                                                                             |
|-----------------------------------------------------------------------------|
| Limit States       | Load# |Location|  Demand  | Capacity |Ratio| Reference |
|--------------------|-------|--------|----------|----------|-----|-----------|
| Tension            |     1 |   0.00 |  -10.000 |   31.104 |0.322|Sec. D2    |
|   Yielding         |     1 |   0.00 |  -10.000 |   31.104 |0.322|Sec. D2    | 
|   Rupture          |     1 |   0.00 |  -10.000 |   37.584 |0.266|Sec. D3    | 
| Compression        |   -   |   -    |     -    |   11.283 |  -  |Sec. E3    |
|   Local Comp       |   -   |   -    |     -    |   11.283 |  -  |Sec. E3    |
|   Axial Comp       |   -   |   -    |     -    |   15.671 |  -  |Sec. E2    |
| Bending            |   -   |   -    |     -    |   14.721 |  -  |Sec. F2    |
|   Major Local Bend |   -   |   -    |     -    |   14.756 |  -  |Sec. F3    |
|   Minor Local Bend |   -   |   -    |     -    |   14.846 |  -  |Sec. F3    |
|   Major Sectional  |   -   |   -    |     -    |   48.929 |  -  |Sec. F2    |
|   Minor Sectional  |   -   |   -    |     -    |   30.019 |  -  |Sec. F2    |
|   LTB Major        |   -   |   -    |     -    |   14.721 |  -  |Sec. F2    |
|   LTB Minor        |   -   |   -    |     -    |   23.956 |  -  |Sec. F2    |
| Shear              |   -   |   -    |     -    |    5.150 |  -  |Sec. G2    |
|   Major Shear (Z)  |   -   |   -    |     -    |    5.150 |  -  |Sec. G2    |
|   Minor Shear (Y)  |   -   |   -    |     -    |    8.154 |  -  |Sec. G2    |
| Interaction        |     1 |   0.00 |     -    |     -    |0.322|Eq. H1.1-1 |
|   (Bend+Ten) Int1  |     1 |   0.00 |     -    |     -    |0.322|Eq. H1.1-1 |
|-----------------------------------------------------------------------------|
    44. PARAMETER 2
    45. CODE AISI 2016
    46. METHOD ASD
    47. FYLD 36 ALL
    48. FU 58 ALL
    49. FLX 0 ALL
    50. NSF 0.9 ALL
    51. TSA 0 ALL
    52. TRACK 2 ALL
    53. CHECK CODE ALL
 STEEL DESIGN    
   WARNING # 14 ~ Channel front to front member #     1 will be considered welded throughout length.
   Spacing will not be considered.
      STAAD SPACE                                              -- PAGE NO.    5 
            STAAD.Pro CODE CHECKING - (AISI S100-16) [ASD ] (v1.0)
           ********************************************************
ALL UNITS ARE IN "INCH" AND "KIP " (U.N.O.)
|-----------------------------------------------------------------------------|
|  MEMBER:     1     SECTION:FR  600CU125-54     LEN:  120.000     LOC:   0.000 |
| STATUS: PASS       RATIO:  0.483             REF: Sec. D2       LC:      1  |
|-----------------------------------------------------------------------------|
| DESIGN FORCES:                                                              |
|  Location:    0.000  Criteria:   Sec. D2              LC:           1       |
|  Fx:(T)      -10.000       Fy:        -0.000          Fz:      -0.000       |
|  Mx:           0.000       My:        -0.000          Mz:      -0.000       |
|-----------------------------------------------------------------------------|
| SECTION PROPERTIES:                                                         |
|  Ag:         0.96000       Az:     0.25096            Ay:     0.66958       |
|  Cz:         0.20400       Cy:     3.09900                                  |
|  Iz:         4.68000       Iy:     1.15815             J:     0.00104       |
|  Sz:         1.51016       Sy:     0.92652                                  |
|  Rz:         2.20794       Ry:     1.09837            Cw:     0.00000       |
|-----------------------------------------------------------------------------|
| MATERIAL INFO:                                                              |
|  Fy:    36.000        Fu:    58.000      E:  29000.000       G:  11200.000  |
|-----------------------------------------------------------------------------|
| DESIGN PROPERTIES:                                                          |
|  Member Length:   120.000   Lz:   120.000   Ly:   120.000   Lb:       0.000 |
| DESIGN PARAMETERS:                                                          |
|  Kz:   1.000    Ky:   1.000    NSF:  0.900                                  |
|-----------------------------------------------------------------------------|
| CRITICAL SLENDERNESS:                                                       |
|-----------------------------------------------------------------------------|
|  LC :     1   Actual :  109.253   Allowable :  300.000   Ratio :   0.364    |
|-----------------------------------------------------------------------------|
|  Section Dimension Check      |    Ratio     |    Limit     |     Status    |
|-----------------------------------------------------------------------------|
|  Radius To Thickness Ratio    |      1.500   |     10.000   |      PASS     |
|  Width To Thickness Ratio     |     17.085   |    500.000   |      PASS     |
|  Web Depth To Thickness Ratio |    104.505   |    200.000   |      PASS     |
|-----------------------------------------------------------------------------|
      STAAD SPACE                                              -- PAGE NO.    6 
            STAAD.Pro CODE CHECKING - (AISI S100-16) [ASD ] (v1.0)
           ********************************************************
ALL UNITS ARE IN "INCH" AND "KIP " (U.N.O.)
|                                              - MEMBER:       1 (Contd.....) |
|                                                                             |
|-----------------------------------------------------------------------------|
| Limit States       | Load# |Location|  Demand  | Capacity |Ratio| Reference |
|--------------------|-------|--------|----------|----------|-----|-----------|
| Tension            |     1 |   0.00 |  -10.000 |   20.695 |0.483|Sec. D2    |
|   Yielding         |     1 |   0.00 |  -10.000 |   20.695 |0.483|Sec. D2    | 
|   Rupture          |     1 |   0.00 |  -10.000 |   25.056 |0.399|Sec. D3    | 
| Compression        |   -   |   -    |     -    |    7.375 |  -  |Sec. E3    |
|   Local Comp       |   -   |   -    |     -    |    7.375 |  -  |Sec. E3    |
|   Axial Comp       |   -   |   -    |     -    |   10.242 |  -  |Sec. E2    |
| Bending            |   -   |   -    |     -    |    9.795 |  -  |Sec. F2    |
|   Major Local Bend |   -   |   -    |     -    |    9.818 |  -  |Sec. F3    |
|   Minor Local Bend |   -   |   -    |     -    |    9.878 |  -  |Sec. F3    |
|   Major Sectional  |   -   |   -    |     -    |   32.554 |  -  |Sec. F2    |
|   Minor Sectional  |   -   |   -    |     -    |   19.973 |  -  |Sec. F2    |
|   LTB Major        |   -   |   -    |     -    |    9.795 |  -  |Sec. F2    |
|   LTB Minor        |   -   |   -    |     -    |   15.939 |  -  |Sec. F2    |
| Shear              |   -   |   -    |     -    |    3.388 |  -  |Sec. G2    |
|   Major Shear (Z)  |   -   |   -    |     -    |    3.388 |  -  |Sec. G2    |
|   Minor Shear (Y)  |   -   |   -    |     -    |    5.364 |  -  |Sec. G2    |
| Interaction        |     1 |   0.00 |     -    |     -    |0.483|Eq. H1.1-1 |
|   (Bend+Ten) Int1  |     1 |   0.00 |     -    |     -    |0.483|Eq. H1.1-1 |
|-----------------------------------------------------------------------------|