Helideck on top of the building, Factor safety and loading design question.

[azcrilez]

Hi, I'm new here.

My currently job is to design concrete slab to support helicopter on top of the building, and I'm not sure which factors of safety should be used.

I looked for the ICAO docs. It's said in the Doc9261 (Heliport manual) that factor of safety(FS) 1.5 should be applied for normal impact landing, and FS 2.5 in case of Emergency landing, but I don't know after I use this FS. 2.5, with a strength design method, should I multiply it again with FS 1.6 for Live load or not(1.4DL + 1.6LL)

It's not described in the doc.

Thank you.

 

[BUGGAR]

We did some helipads to FAA regulations and their safety factors were all based on allowable stress design. When we called to discuss some possible modifications to these factors, the FAA people (not engineers?) had no idea what ultimate strength design was.