Use of Embedded Walls for Mitigation of Liquefaction-Induced Displacement in Slopes and Embankments

A study of effectiveness of ground improvement for liquefaction mitigation

“…The feasibility and effectiveness of DMM walls as underground barriers in liquefiable soils have been both experimentally and analytically evaluated (Tanaka et al, 2000;Motamed et al, 2010). Increasing the rigidity of embedded walls, in terms of increasing wall thickness or elastic modulus or bending stiffness, in liquefiable soil can reduce the deformation of liquefiable soil (Kogai et al, 2000). The wall stiffness, dimensions and installation layout of the DMM mixed walls are the main design parameters in liquefaction mitigation.…”

“…In this study, the wall thickness and depth is 1 m and the full thickness of the backfill soil layer (15 m), respectively. By restricting the rotation and displacement at the bottom of DMM mixed walls, the DMM mixed walls are "fixed" at the bottom of the backfill layer since the fixed-end wall has been proved to be more effective than the floating-type wall (Kogai et al, 2000;Motamed et al, 2010). The properties and stress-strain envelope of DMM-mixed materials are shown in Chapter 5, and are not repeated herein.…”

“…2) Stone columns and DMM been proved to be effective in reducing vertical and lateral deformation induced by liquefaction, respectively (Tanaka et al, 2000;Kogai et al, 2000;Yasuda et al, 2004;Mitchell 2008), for different type of structures prone to liquefactioninduced damage;…”

“…3) DMM walls as the underground barrier have been installed in the liquefiable backfill soil behind the quay wall to reduce the dynamic lateral earth pressure under seismic conditions (Kogai et al, 2000) Therefore, the combination of stone column and DMM wall is expected to improve the seismic performance of the quay wall-soil system from two aspects: 1) Reducing the vertical settlement and loss of bearing capacity of foundation soil, which leads to a reduced deformation of its supported caisson quay wall;…”