Abstract:
Deep mixing methods have been used to mitigate the effects of earthquake-induced liquefaction for a wide range of civil infrastructure. Soil-cement reinforcements can reduce the potential for triggering of liquefaction, reduce lateral and vertical ground deformations, and provide support for overlying structures. Design analysis methods range from simplified equivalent-static methods to nonlinear dynamic analysis methods depending on project specific constraints. Simplified analysis methods are reviewed for unit-cell idealizations of discrete columns and grid systems, including relationships for cyclic stress ratio reductions and equivalent shear wave velocities. Nonlinear dynamic analyses for embankment dams with deep mixing treatments are discussed following a review of recent dam remediation projects. Numerical simulations of a centrifuge model test of an embankment on a liquefiable foundation layer treated with soil-cement panels are used to evaluate common analysis practices. Ongoing challenges and opportunities are discussed.