[1] Degenkolb Engineers, San Francisco, CA 94104 USA
[2] Univ Texas Austin, Engn, Austin, TX 78712 USA
[3] ACI Tech Act Comm, San Francisco, CA USA
[4] Dept Civil & Environm & Architectural Engn, Austin, TX USA
[5] Univ Texas Austin, Austin, TX 78712 USA
[6] Phil M Ferguson Struct Engn Lab, Austin, TX USA