Abstract
Earthquake resistance of pile foundations, constructed in composite ground which was formed using deep mixing method for the purposes of improving shear strength in soft ground or sandy ground subject to liquefaction was verified through a two-dimensional nonlinear dynamic finite element analysis. As a result, it was revealed that the displacement of pile foundations and the strain of piles were restrained by composite ground around piles, and that the earthquake resistance of pile foundations was improved. It was also found that the earthquake resistance of pile foundations depends on the improved strength, the range of composite ground. The composite ground pile method is applicable for both Level 1 and Level 2 earthquake loadings.
