Validate STAAD Output Deflection Check

Eren Jaeger — Wed, 06 Mar 2019 03:13:52 GMT

Hi,

I'm trying to check the results of the "Deflection Check" found in the Output file if it matches the values I get if I try to calculate it manually using the values available in the STAAD Tables.

For example, in Beam 16, I used DFF = 240 and using a length of 5.7116m the deflection limit should be 23.80mm but in the Output file the value shown is 9.37mm (converting it from cm to mm) .

Same for the deflection in the output file which shows 3.94mm, I would like to verify if it really is the maximum deflection in the indicated location and load combination using the tables.

I've attached the results below.

STAAD.PRO CODE CHECKING - (AISC-360-10-LRFD) v1.4a
********************************************

ALL UNITS ARE - KN METE (UNLESS OTHERWISE Noted)

MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/
FX MY MZ LOCATION
=======================================================================

* 16 ST W6X15 (AISC SECTIONS)
FAIL Eq. H1-1b 1.108 223
1.09 T -0.58 -29.71 5.71
|-----------------------------------------------------------------------|
| SLENDERNESS |
| Actual Slenderness Ratio : 155.031 L/C : 234 |
| Allowable Slenderness Ratio : 200.000 LOC : 0.00 |
|-----------------------------------------------------------------------|
| STRENGTH CHECKS |
| Critical L/C : 223 Ratio : 1.108(FAIL) |
| Loc : 5.71 Condition : Eq. H1-1b |
|-----------------------------------------------------------------------|
| DESIGN FORCES |
| Fx: 1.094E+00(T ) Fy: 2.613E+01 Fz: -2.013E-01 |
| Mx: -1.987E-02 My: -5.845E-01 Mz: -2.971E+01 |
|-----------------------------------------------------------------------|
| SECTION PROPERTIES (UNIT: CM ) |
| Azz: 1.340E+01 Ayy: 8.888E+00 Cw: 2.054E+04 |
| Szz: 1.592E+02 Syy: 5.099E+01 |
| Izz: 1.211E+03 Iyy: 3.879E+02 Ix: 4.204E+00 |
|-----------------------------------------------------------------------|
| MATERIAL PROPERTIES |
| Fyld: 248000.002 Fu: 399895.953 |
|-----------------------------------------------------------------------|
| Actual Member Length: 5.712 |
| Design Parameters |
| Kz: 1.00 Ky: 1.00 NSF: 1.00 SLF: 1.00 CSP: 12.00 |
|-----------------------------------------------------------------------|
| SECTION CLASS FLANGE / l lp lr |
| WEB |
| Compression : Non-Slender 11.52 N/A 16.10 |
| Non-Slender 23.78 N/A 42.84 |
| Flexure : Non-Compact 11.52 10.93 28.75 |
| Compact 23.78 108.10 163.88 |
STAAD SPACE -- PAGE NO. 174

STAAD.PRO CODE CHECKING - (AISC-360-10-LRFD) v1.4a
********************************************

ALL UNITS ARE - KN METE (UNLESS OTHERWISE Noted)

|-----------------------------------------------------------------------|
| CHECK FOR AXIAL TENSION |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Yield 1.44E+00 6.38E+02 0.002 Eq. D2-1 219 5.71 |
| Rupture 1.44E+00 8.57E+02 0.002 Eq. D2-2 219 5.71 |
|-----------------------------------------------------------------------|
| CHECK FOR AXIAL COMPRESSION |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Maj Buck 1.24E+00 4.30E+02 0.003 Eq. E3-1 49 0.00 |
| Min Buck 1.24E+00 1.90E+02 0.007 Eq. E3-1 49 0.00 |
| Flexural |
| Tor Buck 1.24E+00 4.44E+02 0.003 Eq. E4-1 49 0.00 |
| Intermediate |
| Results Ag KL/r Fcr Fe Pn |
| Maj Buck 2.86E-03 87.74 1.67E+05 2.63E+05 4.78E+02 |
| Min Buck 2.86E-03 155.03 7.38E+04 8.42E+04 2.11E+02 |
| Flexural Ag Fcr Pn |
| Tor Buck 2.86E-03 1.73E+05 4.94E+02 |
|-----------------------------------------------------------------------|
| CHECK FOR SHEAR |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Major 2.01E-01 1.79E+02 0.001 Eq. G2-1 223 0.00 |
| Minor 2.61E+01 1.32E+02 0.198 Eq. G2-1 223 5.71 |
| Intermediate |
| Results Aw Cv Kv h/tw Vn |
| Major 1.34E-03 1.00 1.20 11.52 1.99E+02 |
| Minor 8.89E-04 1.00 0.00 23.78 1.32E+02 |
|-----------------------------------------------------------------------|
| CHECK FOR BENDING-YIELDING |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Major 2.97E+01 3.95E+01 0.752 Eq. F2-1 223 5.71 |
| Minor -5.85E-01 1.74E+01 0.034 Eq. F6-1 223 5.71 |
| Intermediate Mn My |
| Major 4.39E+01 0.00E+00 |
| Minor 1.93E+01 0.00E+00 |
|-----------------------------------------------------------------------|
| CHECK FOR BENDING-LATERAL TORSIONAL BUCKLING |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Major 2.97E+01 2.77E+01 1.073 Eq. F2-2 223 5.71 |
| Intermediate Mn Me Cb Lp Lr Lb |
| Major 3.08E+01 0.00E+00 1.00 1.86 6.62 5.71 |
STAAD SPACE -- PAGE NO. 175

STAAD.PRO CODE CHECKING - (AISC-360-10-LRFD) v1.4a
********************************************

ALL UNITS ARE - KN METE (UNLESS OTHERWISE Noted)

|-----------------------------------------------------------------------|
| CHECK FOR BENDING-FLANGE LOCAL BUCKLING |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Major 2.97E+01 3.90E+01 0.762 Eq. F3-1 223 5.71 |
| Minor -5.85E-01 1.71E+01 0.034 Eq. F6-2 223 5.71 |
| Intermediate Mn Fcr |
| Major 4.33E+01 0.00E+00 |
| Minor 1.90E+01 0.00E+00 |
|-----------------------------------------------------------------------|
| CHECK FOR FLEXURE TENS/COMP INTERACTION |
| RATIO CRITERIA L/C LOC |
| Flexure Comp 1.108 Eq. H1-1b 223 5.71 |
| Flexure Tens 1.108 Eq. H1-1b 223 5.71 |
| Intermediate Mcx / Mrx / Pc / |
| Mcy Mry Pr |
| Flexure Comp 2.77E+01 2.97E+01 1.90E+02 |
| 1.71E+01 -5.85E-01 0.00E+00 |
| Flexure Tens 2.77E+01 2.97E+01 6.38E+02 |
| 1.71E+01 -5.85E-01 1.09E+00 |
|-----------------------------------------------------------------------|
|-----------------------------------------------------------------------|
| SEISMIC PROVISION(AISC 341:10):- |
| |
| MOMENT FRAME TYPE: SMF |
| |
| SEISMIC CLASSIFICATION: CLASS: l: lhd: |
| FLANGE: l OMF IMF 0.000 0.000 |
| WEB: l OMF IMF 0.000 0.000 |
| |
| REQUIREMENTS:- VALUE CRITERIA |
| EXPECTED FLEXURAL STRENGTH 0.00E+00 |
| BRACING STRENGTH 0.00E+00 |
| BRACING STIFFNESS 0.00E+00 |
| BRACING SPACING 0.00E+00 |
|-----------------------------------------------------------------------|
| |
|-----------------------------------------------------------------------|
| DEFLECTION CHECK: (UNIT: CM ) |
| |
| Limit Span/Deflection (DFF) : 240.000 Limit : 0.937 |
| Span/Deflection : 5.70E+02 Deflection : 0.394 |
| L/C : 399 LOC : 93 |
| Ratio : 0.421 (PASS) |
|-----------------------------------------------------------------------|

I also uploaded the std file.

communities.bentley.com/.../1145.Frame.std

Hoping someone would enlightened me. thanks!

STAAD Seismic Automatically Generated Vertical Forces

Eren Jaeger — Thu, 16 Jul 2020 19:06:40 GMT

Hi,

I have a small warehouse type structure wherein I allowed staad to automatically generate seismic forces. I expect it to generate lateral load only on both X and Z directions but somehow, as shown in the images below, it also generated vertical forces when seismic forces were being calculated along the X-axis.

+X gives additional upward load

-X gives additional downward load

Both + and -Z seems fine.

Can someone point me what did I do wrong?

If in case this is related to the staad version, I am using staad pro V8i ss6 20.07.11.90

communities.bentley.com/.../8080.Frame.std

RAM Connection

John Postlethwaite — Tue, 03 Mar 2020 14:38:00 GMT

Hello,

There is probably a simple and obvious answer to this question but I will ask anyway. Why is it that RAM Connection only deals with the major axis bending moment and vertical shear (and axial) instead of all 3 forces and all 3 moments?

Thanks,

John

Deflection check results in SS6

ADITYA Mishra — Fri, 29 Jul 2016 07:53:30 GMT

I had analyzed and designed the member in staad ss6. On checking the output I found it in a different format unlike Staad SS3. So could u please explain the highlighted terms in the sketch below as I am unable to correlate with the actual displacement results.

Setting the GROUND LEVEL in STAAD Pro

Eren Jaeger — Thu, 24 Jan 2019 07:42:50 GMT

Hi all,

1) Is there a way to set the ground level in STAAD Pro or is the y=0 level the permanent ground level? This is for the purpose of computing the seismic forces because, from what I know, distribution of the computed base shear per level of a structure is related to the distance of a level from the ground surface.

For example, I have to design a 4-storey steel structure. The pedestal protrudes above the ground slab by a 0.5m and in modelling the the steel structure in STAAD, the support, which is the base plate connection, is above the ground slab by 0.5m.
Let's say that the distance from the 2nd floor to the ground level is 3.3m so the distance that will be used in modelling the steel from the 2nd floor to the base plate is 2.8m.

2) Do you neglect the 0.5m distance and just proceed in the modelling and assume the base plate connection as located in the ground?
3) If yes, will this not have any effect in the seismic forces?
4) If no, what do you do for this case?
5) Do I miss something?

Hoping to have some clarity regarding the matter.
Thanks in advance everyone!

Floor Loads Applied Perpendicularly to a Sloping Roof

Eren Jaeger — Fri, 25 Jan 2019 08:30:42 GMT

Hi Sirs,

1) Is there a way to apply floor loads perpendicularly to a sloping roof?

2) What is the use of Inclined Floor check box in the floor load feature of STAAD? Is it to perpendicularly apply the loads on a sloping area? Because I tried switching it on and off but the angle of the load doesn't seem to change. Please see the pictures below.

Thanks!

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Thu, 24 Jan 2019 01:43:12 GMT

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Eren Jaeger's Activities

Validate STAAD Output Deflection Check

STAAD Seismic Automatically Generated Vertical Forces

RAM Connection

Deflection check results in SS6

Setting the GROUND LEVEL in STAAD Pro

Floor Loads Applied Perpendicularly to a Sloping Roof

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