Evaluating ground displacement behind bulkheads

ABSTRACT

Large ground displacements associated with soil liquefaction were observed behind many quay walls and bulkheads at 1995 Great Hanshin(Kobe) earthquake. Horizontal displacements at the quay walls and bulkheads were about 5m maximum and 3m average. The extent of the area affected by the movement of the bulkheads was as far back as 70 m on average behind the bulkheads. In this study, applicability of an effective stress model is reviewed for its capability to simulate these large ground displacements behind bulkheads. The model used for the analysis is a multiple mechanism model defined in strain space. The model parameters are calibrated based on in-situ and laboratory test data using in-situ frozen samples. The results of the analysis indicate that the effective stress model reviewed in this study has a reasonable capability to simulate the large ground displacements behind bulkheads. The results also indicate that the extent of the area behind the wall affected by the wall movement corresponds to the cross sectional area approximated by a circular slip area assumed for evaluating bearing capacity of foundation with respect to an inclined load.(AU)