Experimental study on effects of underground columnar improvement on seismic behaviour of quay wall subjected to liquefaction

摘要

There are various mitigation methods to reduce the structural damage caused by liquefaction. In order to keep the performance of quay wall structures, deep mixing can be utilized as a useful soil improvement method to decrease the residual deformations. Recently, columnar type of deep mixing is expected to be more economical than overall grouting or that of square grid. Effect of soil stabilization pattern, area and position (where the underground columns are placed) is evaluated in this research. By conducting model shaking table tests, features of quay wall behaviour were evaluated based on two different improvement patterns: normal (regular) and irregular. Efficiency of the normal pattern and irregular pattern as well as its area and position are compared with respect to unimproved case. It is inferred that, in soil improvement design, selection of irregular pattern with an appropriate placement area and position can make the seismic behaviour of the structure better.