SeanMD
Structural
- Jun 17, 2005
- 53
I need to supply an axle load rating for a 40 year old concrete tunnel roof. I am looking for guidelines for determining effective widths (one way bending assumed) for point loads and wheel loads for an elevated concrete slab. I don't think the AASHTO code equation (4+.06s) really applies because my slab is about 1.75 feet thick (25 foot span), much thicker than bridge decks.
After searching here I found references to this report be Westergaard, which appears to be the basis for the AASHTO effective width equation. But I can't find it anywhere and neither can the company librarian. Any suggestions on how to get it?
Or suggestions on other methods to obtain a reasonable effective width? The AASHTO equation would give me 5.5 feet, but I think given that is extremely conservative. I have #6@12 to distribute the load out and I would think something like 8*d (12 feet) would be more reasonable. I think a FEA would give me more capacity than I want to use. What I really want is something to stick in my calcs to verify my 8*d eff width.
Any idea?
After searching here I found references to this report be Westergaard, which appears to be the basis for the AASHTO effective width equation. But I can't find it anywhere and neither can the company librarian. Any suggestions on how to get it?
Or suggestions on other methods to obtain a reasonable effective width? The AASHTO equation would give me 5.5 feet, but I think given that is extremely conservative. I have #6@12 to distribute the load out and I would think something like 8*d (12 feet) would be more reasonable. I think a FEA would give me more capacity than I want to use. What I really want is something to stick in my calcs to verify my 8*d eff width.
Any idea?