Temporary shielding design

[bgrove]

I am currnetly in the process of designing debri shielding for a bridge. The exterior parapets and some of the deck is being removed. The exterior portion will be supported by overhang brackets and the interior bay will have wooden 2" x 12" planks resting on the bottom flanges. My basic question is this: Where can I find loading information for falling debri or any kind of demo work? I have looked in the AASHTO Construction handbook and guide spec book for temporary work and I can't find anything. I have done overhang falsework design before but I have never done shielding design. It seems to me that falling debri will have more of a load impact than simple dead load but I am not sure how to calculate it. If anyone has any information for me I would appreciate it. Thanks.

 

[MotorCity]

I would check with OSHA. They may have some useful information. Good luck.

 

[yli]

We specify 100 psf live load (impact included) for shielding design in our contract specifications; we also specify that any debris has to be removed within 24 hours.

 

[LPPE]

F=ma

 

[bridgebuster]

I've seen specs that require, in addition to 100 - 150 psf live load, that the design also be sufficient for a 1000# concentrated load falling 6'.

Sheilding design requires a bit of educated guess work as to the loads.