Chapter 2 Literature Review on Liquefaction and Ground Densification for Liquefaction Mitigation

One of the most dramatic causes of damage of structures during earthquakes has been the development of liquefaction in saturated cohesionless deposits. These deposits have tendency to densify when subjected to earthquake loading. However, when saturated, the tendency to densify causes the excess pore water pressure to increase. This, in turn, results in the effective stress of soil to decrease. As a consequence, the cohesionless deposit will lose a substantial strength and a subsequent reduction in soil volume until the excess pore water pressure has a chance to dissipate. The phenomenon of pore pressure build-up following with the loss of soil strength is known as liquefaction (Committee on Earthquake Engineering, 1985). The potential damage caused by liquefaction phenomena includes: 1) Loss of bearing capacity, 2) Excessive settlement, 3) Lateral spreading, 4) Flow failure, and 5) Ground oscillation. The following sections will discuss each phenomenon.