Reduction of liquefaction potential using high discharge capacity drains

摘要

Most liquefaction mitigation techniques use design systems which incorporate drainage as a primary or secondary mechanism to increase the factor of safety against potential failure. This paper briefly describes the analysis methodology to evaluate the performance of a layered deposit treated with high discharge capacity drains. For stratified soil deposits with initial water table at depth, water discharge results in a change of water level within the drain leading to a significant retardation of flow in the system. This in turn results in an increase in the excess pore pressures developed in the soil deposit, which is not considered by conventional analyses or commonly available design charts. The methodology is equally applicable to granular piles and gravel and stone column drains as well as the new prefabricated products currently available in the market.