staad pro v8i (20.07.09.31) issue

dear staad master.

i'm new member in here. i love this forum because i can find the answers about lots of my own problem with staad besides reading technical manual reference from staad.

now i'm working with (maybe) the latest patch released from staad pro v8i series 4 20.07.09.31. and i'm using AISC 360-10 code because of client requirement for my project.

then i contact to IT to upgrade the staad to series 4 because staad has the 360-10 code.

unfortunately. i have some questions regarding AISC 360-10 code.

question no 1.

how to change base staad unit ?

i'm in Indonesia, we use Metric instead of English. I change the base-units in configuration to Metric, but the output still using English-units.

i change the configuration file from staadpro20070.ini still doesn't give any change. i think the AISC 360-10 code output doesn't give the metric output.

when i check using different code (9th edition) the output give me metric unit.

please, bentley staad creator, could you fix this ?

question no 2.

in the history version of staad series 4 (http://communities.bentley.com/products/structural/structural_analysis___design/b/analysis_and_design_blog/archive/2012/12/05/staad-pro-v8i-selectseries-4-patch-release.aspx )

it is noted 

A) 04 The AISC 360-10 steel design module has been enhanced with the
reintroduction of the MAIN and TMAIN parameters. Setting either to 1.0 will
bypass any slenderness checks."

in example "STAADPro_V8i_AISC_13th_Ed_Design_Example_Verification.pdf" , the input shows : 

and the output :

in my staad, when i set MAIN or TMAIN to 1.0, the input

and the result shows :

so the staad didn't bypassed the slenderness check ??

question no 3 :

3. what is the value of the slenderness ratio of : compression member and tension member ?

based on my knowledge, for compression member is 200, and for tension is 300.

the staad seems inconsistent for "MAIN" command for 360-10  code.

in some cases, the kL/r is exceed and give me FAIL for slender member when i'm using the 9th edition code, or 360-05.

but in 360-10, staad give me PASS.

 

what should i do ?

Parents
  • Hello,

    Question 1:

    Presently the Staad reports the design result as per AISC 360-100 in e the English Unit System only . The metric system will be introduced in the upcoming releases .

    Question 3 :

    From the screenshot it seems, that the FX is reported for LC 5013 and the slenderness check is done for LC 51.

    Can you kindly send us the model.



  • dear Shany.

    thank you for answering question 1.

    for question 3.

    i can't share the staad file due to company regulation. i'm so sorry.

    but i can show you my study staad for stair tower. this staad represent my problems.

    i check using AISC 360-05, staad says error due to slenderness exceeds. in 360-10. staad doesn't give any error message.

    for my comparison using beam no 410.

    using 360-05 code, staad says FAIL (left image), and PASS in the right image (360-10 code). the kL/r value are same. but the ratio is totally different. why ?

    in the left image, i think the staad is correct, because the compression member allowable slenderness is 200. if the kL/r exceed or over 200 ,the member is FAIL.

    but in the right image, 360-10 code says the member is a tension member. which mean the slenderness ratio is "should be" 300. right ? so it PASSED.

    however, in the output result i will show you in below image.

    ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

    staad pro using different load case for strength check and slenderness check. am i right ?

    ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

    above explanation : critical ratio, and biggest force happens due to load case 105 and the member experiencing tension. but for slenderness check, staad (using 360-10 code) check using LC 101. the actual slenderness is 228 which over than the allowable (200 for compression). but staad doesn't say this a problem. it is PASS(ed).

    i do checking via Post-Process to earn the beam force. it is true, that in the LC 105 the member is tension. and the LC 101 makes the beam compress.

    but, why staad using the LC 101 instead of LC 105 for slenderness check ?

    what is wrong in here ?

    study.zip
Reply
  • dear Shany.

    thank you for answering question 1.

    for question 3.

    i can't share the staad file due to company regulation. i'm so sorry.

    but i can show you my study staad for stair tower. this staad represent my problems.

    i check using AISC 360-05, staad says error due to slenderness exceeds. in 360-10. staad doesn't give any error message.

    for my comparison using beam no 410.

    using 360-05 code, staad says FAIL (left image), and PASS in the right image (360-10 code). the kL/r value are same. but the ratio is totally different. why ?

    in the left image, i think the staad is correct, because the compression member allowable slenderness is 200. if the kL/r exceed or over 200 ,the member is FAIL.

    but in the right image, 360-10 code says the member is a tension member. which mean the slenderness ratio is "should be" 300. right ? so it PASSED.

    however, in the output result i will show you in below image.

    ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

    staad pro using different load case for strength check and slenderness check. am i right ?

    ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

    above explanation : critical ratio, and biggest force happens due to load case 105 and the member experiencing tension. but for slenderness check, staad (using 360-10 code) check using LC 101. the actual slenderness is 228 which over than the allowable (200 for compression). but staad doesn't say this a problem. it is PASS(ed).

    i do checking via Post-Process to earn the beam force. it is true, that in the LC 105 the member is tension. and the LC 101 makes the beam compress.

    but, why staad using the LC 101 instead of LC 105 for slenderness check ?

    what is wrong in here ?

    study.zip
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