V.ASME NF 3000 2004 STYPE 1 Pipe

Verify the design results an austenitic stainless steel pipe section, designed as per ASME NF 3000 2004.

Details

A beam (beam no. 7 in the model) of length 10 ft is loaded with a uniformly distributed load of 1 kip/ft over the whole span, and axial compressive loads of 100 kip at both ends. The beam is assigned with a steel pipe section of PIPS120 and is designed in accordance with ASME NF3000 2004.

The austenitic stainless steel has a yield strength of 36 ksi, an ultimate rupture strength of 58 ksi, and a modulus of elasticity of 29,000 ksi.

Validation

From the analysis:

F_x = 100.145 kip
F_y = 5 kip (at ends)
M_z = 97.683 in·k (at mid-span)
M_y = 10.798 in·k

(KL/r)z = Slenderness Ratio along Z-Axis = 27.44 =(KL/r)_y = Slenderness Ratio along Y-Axis < 200 Hence OK (Refer NF-3322.2(c)(1))

Check Against Axial Compression

As per clause NF 3322.2(d)(2)(c),

OD/t_w = 12.75/0.35 = 36.429 < 3,300/F_y = 91.667

Since (KL/r)_y = 27.44 = (kl/r)_z < 120

As per NF 3322.1(c)(2)(a),

Allowable compressive stress, $F_{a} = F_{y} (0.47 - \frac{k l / r}{444}) = 14.7 ksi$

Actual compressive stress f_a = F_x/A_x = 7.31 ksi

Ratio = 0.497

Check Against Bending

Allowable Stress along Major Axis (Z-Axis):

Since as per clause NF 3322.1(d)(1)(a)(7),

OD/t_w = 12.75/0.35 = 36.429 < 3,300/F_y = 91.67

Thus, allowable bending stress is obtained by treating the section as compact.

Fbcz = 0.66×F_y = 23.76 ksi = Fbtz

Allowable Stress along Minor Axis (Y-Axis):

Here also, allowable stress along minor axis is given as Fbty=0.66xFYLD = 23.8 ksi = Fbcy

Actual Bending Stress along Major Axis (Z-Axis):

Mz = 97.683 in·k

Bending Tensile Stress = fbtz = (Mz/Iz)×(OD/2) = 2.38 ksi < 23.8 ksi, Hence OK.

Bending Compressive Stress = fbcz = 2.38 ksi < 23.8 ksi, Hence safe.

Actual Bending Stress along Minor Axis (Y-Axis):

My = 10.798 in·k

Bending Tensile Stress = fbty = (Mz/Iz)×(OD/2) = 0.263 ksi < 23.8 ksi, Hence OK.

Bending Compressive Stress = fbcy = 0.263 ksi < 23.8 ksi , Hence safe.

Check for Combined Axial Compression and Bending

Cmz = Cmy = 1 (as provided in the input)

Now, fa = 7.31 ksi, Fa = 14.7 ksi, fbcz = 2.38 ksi, Fbcz = 23.8 ksi, fbcy = 0.263 ksi, Fbcy = 23.8 ksi

Since fa/ Fa = 7.31 / 14.7 = 0.497 > 0.15

{F_{e z}}^{'} = \frac{π^{2} \times E}{2.15 \times {(\frac{k l}{r})}_{z}^{2}} = 176.804 ksi

(NF 3322.1(e)(1) )

{F_{e y}}^{'} = \frac{π^{2} \times E}{2.15 \times {(\frac{k l}{r})}_{y}^{2}} = 176.804 ksi

(NF 3322.1(e)(1) )

From Eqn. 20:

$\frac{f_{a}}{F_{a}} + \frac{C_{m z} \times f_{b z}}{(1 - \frac{f a}{F^{'} e z}) \times F_{b z}} + \frac{C_{m y} \times f_{b y}}{(1 - \frac{f a}{F^{'} e y}) \times F_{b y}} = 0.613 < 1$ , Hence safe (critical ratio)

From Eqn. 21:

$\frac{f_{a}}{0.6 F_{y}} + \frac{f_{b z}}{F_{b z}} + \frac{f_{b y}}{F_{b y}} = 0.449 < 1$ , Hence safe

Check Against Shear

Actual Shear along Major Axis:

V_y = 2× OD × t_w = 8.925 in²

f_vy = 5 kip / 8.925 in² = 0.56 ksi

(No shear along minor axis; f_vz = 0)

Allowable Shear:

As per NV 3322.1(b)(1), allowable shear stress, F_v = 0.4×F_y = 14.4 ksi

Ratio = 0.039

Results

Table 1. Comparison of results
Result Type	Reference	STAAD.Pro	Difference
Slenderness ratio	27.44	27.44	none
Actual compressive stress (ksi)	7.31	7.31	none
Allowable compressive stress (ksi)	14.7	14.7	none
Actual bending stress; major axis (ksi)	2.38	2.38	none
Allowable bending stress, major axis (ksi)	23.8	23.8	none
Actual bending stress, minor axis (ksi)	0.263	0.263	none
Allowable bending stress, minor axis (ksi)	23.8	23.8	none
Combined interaction ratio	0.613	0.613	none
Shear stress, major axis (ksi)	0.039	0.039	none

STAAD.Pro Input File

The file C:\Users\Public\Public Documents\STAAD.Pro CONNECT Edition\Samples\ Verification Models\09 Steel Design\US\ASME\ASME NF 3000 2004 STYPE 1 Pipe.STD is typically installed with the program.

STAAD SPACE
START JOB INFORMATION
ENGINEER DATE 20-Mar-19
END JOB INFORMATION
*****************************************************************************
*This problem has been created to validate the program calculated design 
*results of ASME NF 3000 2004 pipe section with STYPE 1 parameter
*****************************************************************************
INPUT WIDTH 79
SET SHEAR
UNIT FEET KIP
JOINT COORDINATES
1 0 0 0; 2 0 10 0; 3 10 10 0; 4 10 0 0; 5 0 0 10; 6 0 10 10; 7 10 10 10;
8 10 0 10;
MEMBER INCIDENCES
1 1 2; 2 2 3; 3 3 4; 4 2 6; 5 3 7; 6 5 6; 7 6 7; 8 7 8;
DEFINE MATERIAL START
ISOTROPIC STEEL
E 4.176e+06
POISSON 0.3
DENSITY 0.489024
ALPHA 6.5e-06
DAMP 0.03
TYPE STEEL
STRENGTH RY 1.5 RT 1.2
END DEFINE MATERIAL
MEMBER PROPERTY AMERICAN
1 TO 8 TABLE ST PIPS120
CONSTANTS
MATERIAL STEEL ALL
SUPPORTS
1 4 5 8 FIXED
LOAD 1 LOADTYPE Dead  TITLE DL-1
JOINT LOAD
6 FX 100
7 FX -100
LOAD 2 LOADTYPE Dead  TITLE DL-2
MEMBER LOAD
2 4 5 7 UNI GY -1
LOAD COMB 3 COMBINATION LOAD CASE 3
1 1.0 2 1.0 
PERFORM ANALYSIS
UNIT INCHES KIP
PRINT MEMBER FORCES LIST 7
SECTION 0.25 0.5 0.75
PRINT MEMBER SECTION FORCES LIST 7
PRINT MATERIAL PROPERTIES LIST 7
PRINT MEMBER PROPERTIES LIST 7
LOAD LIST 3
PARAMETER 1
CODE NF3000 2004
STYPE 1 ALL
CMZ 1 ALL
CMY 1 ALL
TRACK 2 ALL
CHECK CODE MEMB 7
FINISH

STAAD.Pro Output

                                                                  PAGE NO.    1
             ****************************************************        
             *                                                  *        
             *           STAAD.Pro CONNECT Edition              *        
             *           Version  22.12.00.***                  *        
             *           Proprietary Program of                 *        
             *           Bentley Systems, Inc.                  *        
             *           Date=    OCT 27, 2022                  *        
             *           Time=    15:41:51                      *        
             *                                                  *        
             *  Licensed to: Bentley Systems Inc                *        
             ****************************************************        
     1. STAAD SPACE
INPUT FILE: ASME NF 3000 2004 STYPE 1 Pipe.STD
     2. START JOB INFORMATION
     3. ENGINEER DATE 20-MAR-19
     4. END JOB INFORMATION
     6. *****************************************************************************
     7. *THIS PROBLEM HAS BEEN CREATED TO VALIDATE THE PROGRAM CALCULATED DESIGN
     8. *RESULTS OF ASME NF 3000 2004 PIPE SECTION WITH STYPE 1 PARAMETER
     9. *****************************************************************************
    11. INPUT WIDTH 79
    12. SET SHEAR
    13. UNIT FEET KIP
    14. JOINT COORDINATES
    15. 1 0 0 0; 2 0 10 0; 3 10 10 0; 4 10 0 0; 5 0 0 10; 6 0 10 10; 7 10 10 10
    16. 8 10 0 10
    17. MEMBER INCIDENCES
    18. 1 1 2; 2 2 3; 3 3 4; 4 2 6; 5 3 7; 6 5 6; 7 6 7; 8 7 8
    19. DEFINE MATERIAL START
    20. ISOTROPIC STEEL
    21. E 4.176E+06
    22. POISSON 0.3
    23. DENSITY 0.489024
    24. ALPHA 6.5E-06
    25. DAMP 0.03
    26. TYPE STEEL
    27. STRENGTH RY 1.5 RT 1.2
    28. END DEFINE MATERIAL
    29. MEMBER PROPERTY AMERICAN
    30. 1 TO 8 TABLE ST PIPS120
    31. CONSTANTS
    32. MATERIAL STEEL ALL
    33. SUPPORTS
    34. 1 4 5 8 FIXED
    35. LOAD 1 LOADTYPE DEAD  TITLE DL-1
    36. JOINT LOAD
    37. 6 FX 100
    38. 7 FX -100
    39. LOAD 2 LOADTYPE DEAD  TITLE DL-2
    40. MEMBER LOAD
      STAAD SPACE                                              -- PAGE NO.    2
    41. 2 4 5 7 UNI GY -1.
    42. LOAD COMB 3 COMBINATION LOAD CASE 3
    43. 1 1.0 2 1.0
    44. PERFORM ANALYSIS
            P R O B L E M   S T A T I S T I C S
            -----------------------------------
     NUMBER OF JOINTS          8  NUMBER OF MEMBERS       8
     NUMBER OF PLATES          0  NUMBER OF SOLIDS        0
     NUMBER OF SURFACES        0  NUMBER OF SUPPORTS      4
           Using 64-bit analysis engine.
           SOLVER USED IS THE IN-CORE ADVANCED MATH SOLVER
   TOTAL      PRIMARY LOAD CASES =     2, TOTAL DEGREES OF FREEDOM =      24
   TOTAL LOAD COMBINATION  CASES =     1  SO FAR.
    45. UNIT INCHES KIP
    46. PRINT MEMBER FORCES LIST 7
  MEMBER   FORCES   LIST     7        
      STAAD SPACE                                              -- PAGE NO.    3
   MEMBER END FORCES    STRUCTURE TYPE = SPACE
   -----------------
   ALL UNITS ARE -- KIP  INCH     (LOCAL )
  MEMBER  LOAD  JT     AXIAL   SHEAR-Y  SHEAR-Z   TORSION     MOM-Y      MOM-Z
      7    1     6     99.31     -0.00    -0.00      0.00     10.80     -14.22
                 7    -99.31      0.00     0.00     -0.00    -10.80      14.22
           2     6      0.83      5.00    -0.00     -0.00      0.00      66.53
                 7     -0.83      5.00     0.00      0.00      0.00     -66.53
           3     6    100.14      5.00    -0.00      0.00     10.80      52.32
                 7   -100.14      5.00     0.00     -0.00    -10.80     -52.32
   ************** END OF LATEST ANALYSIS RESULT **************
    47. SECTION 0.25 0.5 0.75
    48. PRINT MEMBER SECTION FORCES LIST 7
  MEMBER   SECTION  FORCES   LIST     
      STAAD SPACE                                              -- PAGE NO.    4
   MEMBER FORCES AT INTERMEDIATE SECTIONS
   --------------------------------------
   ALL UNITS ARE -- KIP  INCH
 MEMB  LOAD  SEC       AXIAL   SHEAR-Y   SHEAR-Z       MOM-X       MOM-Y       MOM-Z
     7    1  0.25      99.31     -0.00     -0.00        0.00       10.80      -14.22
             0.50      99.31     -0.00     -0.00        0.00       10.80      -14.22
             0.75      99.31     -0.00     -0.00        0.00       10.80      -14.22
          2  0.25       0.83      2.50     -0.00       -0.00        0.00      -45.97
             0.50       0.83      0.00     -0.00       -0.00       -0.00      -83.47
             0.75       0.83     -2.50     -0.00       -0.00       -0.00      -45.97
          3  0.25     100.14      2.50     -0.00        0.00       10.80      -60.18
             0.50     100.14     -0.00     -0.00        0.00       10.80      -97.68
             0.75     100.14     -2.50     -0.00        0.00       10.80      -60.18
   ************** END OF LATEST ANALYSIS RESULT **************
    49. PRINT MATERIAL PROPERTIES LIST 7
  MATERIAL PROPERTI LIST     7        
      STAAD SPACE                                              -- PAGE NO.    5
   MATERIAL PROPERTIES.
   --------------------
   ALL UNITS ARE - KIP  INCH
  MATERIAL 
           KIND         E          POIS        DENS       ALPHA        DAMP        G
   STEEL                               
             1D    2.90000E+04     0.300   2.83000E-04 6.50000E-06     0.030   1.11538E+04
      STAAD SPACE                                              -- PAGE NO.    6
   MATERIAL PROPERTIES.
   --------------------
   ALL UNITS ARE - KIP  INCH
   MEMBER           E            G          DEN         ALPHA
      7          29000.0      11153.8    0.00028300  0.00000650
   ************ END OF DATA FROM INTERNAL STORAGE ************
    50. PRINT MEMBER PROPERTIES LIST 7
  MEMBER   PROPERTI LIST     7        
      STAAD SPACE                                              -- PAGE NO.    7
   MEMBER PROPERTIES. UNIT - INCH
   -----------------
   MEMB   PROFILE              AX/          IZ/          IY/        IX/  
                               AY           AZ           SZ         SY
     7  ST  PIPS120           13.70       262.00       262.00      524.00
                               7.01         7.01        41.10       41.10
   ************ END OF DATA FROM INTERNAL STORAGE ************
    51. LOAD LIST 3
    52. PARAMETER 1
    53. CODE NF3000 2004
    54. STYPE 1 ALL
    55. CMZ 1 ALL
    56. CMY 1 ALL
    57. TRACK 2 ALL
    58. CHECK CODE MEMB 7
 STEEL DESIGN    
      STAAD SPACE                                              -- PAGE NO.    8
                       STAAD.PRO CODE CHECKING - (  ASME NF3000-04)   v2.0
                       ********************************************
 ALL UNITS ARE - KIP  INCH (UNLESS OTHERWISE Noted)
 MEMBER     TABLE       RESULT/   CRITICAL COND/     RATIO/     LOADING/
                          FX            MY             MZ       LOCATION
 =======================================================================
      7  ST   PIPS120                  (AISC SECTIONS)
                           PASS      NF-EQN-20         0.613         3
                      100.14 C         10.80         -97.68       60.00
 |-----------------------------------------------------------------------------|
 | SLENDERNESS CHECK:    ACTUAL RATIO:  27.44 ALLOWABLE RATIO: 200.00          |
 | ALLOWABLE STRESSES:   (UNIT - KIP  INCH)                                    |
 | AXIAL: 1.47E+01  FCZ: 2.38E+01  FCY: 2.38E+01  FTZ: 2.38E+01  FTY: 2.38E+01 |
 | SHEAR: 1.44E+01                                                             |
 | ACTUAL STRESSES: (UNIT - KIP  INCH)                                         |
 | AXIAL: 7.31E+00  FBZ: 2.38E+00  FBY: 2.63E-01 SHEAR: 0.00E+00               |
 |-----------------------------------------------------------------------------|
 | SECTION PROPERTIES: (UNIT - INCH)                                           |
 | AXX:  13.70  AYY:   7.01  AZZ:   7.01  RZZ:  4.37  RYY:  4.37               |
 | SZZ:      41.10  SYY:      41.10                                            |
 |-----------------------------------------------------------------------------|
 | PARAMETER: (UNIT - KIP  INCH)                                               |
 | KL/R-Z: 27.44   KL/R-Y: 27.44   UNL:  120.0   CMZ:  1.00   CMY:  1.00       |
 | CB: 1.00   FYLD:    36.00   FU:    58.02   NET SECTION FACTOR: 1.00         |
 | CT:  0.75   STEEL TYPE:  1.0  KS:1.000  KV:1.000  KBK:1.000                 |
 |-----------------------------------------------------------------------------|
 | CRITICAL LOADS FOR EACH CLAUSE CHECK (UNITS KIP -INCH)                      |
 | CLAUSE       RATIO  LOAD       FX        VY        VZ        MZ        MY   |
 | TENSION      0.000    0    0.00E+00       -         -         -         -   |
 | COMPRESSION  0.497    3    1.00E+02       -         -         -         -   |
 | COMP&BEND    0.613    3    1.00E+02       -         -    9.77E+01 1.08E+01  |
 | TEN&BEND     0.000    0    0.00E+00       -         -    0.00E+00 0.00E+00  |
 | SHEAR-Y      0.039    3        -     5.00E+00       -         -         -   |
 | SHEAR-Z      0.000    0        -          -    0.00E+00       -         -   |
 |-----------------------------------------------------------------------------|
    59. FINISH
             *********** END OF THE STAAD.Pro RUN ***********         
               **** DATE= OCT 27,2022   TIME= 15:41:52 ****
      STAAD SPACE                                              -- PAGE NO.    9
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