Plume Loads 1

[LeonhardEuler]

All,

Have a couple questions about special loading and finite element analysis.

1) Is there a reliable source I.e UFC DoD,ASCE, or others that provides load combination for acoustic/blast/plume loads? Only thing I have found is AISC design guide that calls for a modification factor of 1.0 on blast loads.

2) Are factored LRFD loads used in FEA models? If so what is the LRFD F.S. applied to von Mises stresses

3) Are von Mises stresses used for non-ductile materials such as concrete? If not what criterion should be used?

Thank you all

 

[WARose]

1) Is there a reliable source I.e UFC DoD,ASCE, or others that provides load combination for acoustic/blast/plume loads? Only thing I have found is AISC design guide that calls for a modification factor of 1.0 on blast loads.

Pretty much every reference I can think of uses 1.0. A army manual (i.e. TM 5-100) recommends a safety factor of 20% (i.e. 1.2) for blast loading.

2) Are factored LRFD loads used in FEA models? If so what is the LRFD F.S. applied to von Mises stresses

3) Are von Mises stresses used for non-ductile materials such as concrete? If not what criterion should be used?

I've never used Von Mises failure criteria for this application because you are going into the plastic range. Typically your limit state will involve the formation of a plastic hinge.

Even for regularly loaded concrete structures, I typically haven't used Von Mises.

 

[KootK]

Yeah, Von Mises doesn't make any sense for brittle materials like concrete.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.

 

[Retrograde]

You can use a compression field approach as described in fib Bulletin 45.