AASHTO Design safety factors

[stjimm]

I am developing an FEA for a bearing and pedestal (column) support for a highway bridge. I know the material specifications for the bearing and steel column. If I know the yield strength of the material, does AASHTO provide a design safety factor based on yield strength for design of structural members? I am new to the AASHTO standarda and am looking for some advice or quidance.
Thank you.

 

[Qshake]

It depends on what AASHTO code your client is using. The current AASHTO is LRFD, Load Factor and Resistance Design and so uses factors for both demand and capacity.

Older AASHTO codes use both LFD and ASD, Load Factor Design and Allowable Stress Design. Load factor design uses load factors to compare to material yield stresses. ASD uses Factors of Safety to reduce the material yield stresses and does not factor loads.

Doesn't really matter which you use but you need to get a hard copy and read it to fully understand what and why your applying to loads and materials.

Regards,
Qshake

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