Load and Resistance Factor Design for Drilled Shafts in Shale for Lateral Loading.

摘要

A research project involving 32 drilled shaft load tests was undertaken to establish LRFD procedures for design of drilled shafts subjected to lateral loads. Tests were performed at two Missouri Department of Transportation (MoDOT) geotechnical research sites. All shafts were founded in shale. Shafts were instrumented to measure the displacement of the shaft head, and the structural response of each shaft was interpreted from strain gage data as well as from ShapeAccelArray (SAA) data. The load tests achieved significant displacement of the top of the shaft, and successfully transferred load into the rock layers. A p-y model was created from the data by using a FEM code to match the measured deflection data. The fitted p-y models were generally stiffer and with greater values of pult than those predicted using the popular stiff clay model of Ensoft's L-PILE. The FEM code was then used to perform reliability calculations and produce resistance factors as a function of the coefficient of variation of the foundation material strength.