Abstract
The lattice-shaped ground improvement by using cement treatment such as the deep mixing method is one of countermeasure methods against liquefaction. Its effectiveness as countermeasure has been examined with a series of model tests and numerical analyses which were conducted by many previous researchers. In this study, a new technique, in which cement treatment is not partially extended down to a non-liquefiable stratum, is proposed for generating more cost benefits. Under this approach, the treated soil that is fixed to the non-liquefiable stratum is considered to be needed with the partial reduction of the improvement depth. The fixed soil decreases the horizontal displacement of the floating-type treated soil, and this can prevent liquefaction in sandy ground under the floating-type treated soil. The dynamic centrifuge model tests executed showed the effect of liquefaction countermeasure by using the technique proposed.
