Seismic Site Class - Shot rock fill

[civilmg]

Does anyone have any literature regarding shear wave velocities in a shot rock fill. The structural engineer is inquiring about obtaining a site class B (as per IBC 2003) for a multi-story building. the site conditions are such that 30 feet of fill is required to achieved proposed subgrade elevation. According to the IBC, this much fill can get you a site class C, at best (even with deep foundations), unless you can prove otherwise. We believe that our best chance of satisfying this criteria is to use well placed, well graded shot rock as the fill material (there is plenty of it on site). We want to perform shear wave analyses to verify the site class, but (as I know you are all aware) the client is not keen on taking the chance on placing 30 feet of shot rock fill and not get the results that we are hoping to achieve. I believe that, if literature exists, we might be able to convince the client to pay for the tests.

Thanks for the hel;