Dynamic Centrifuge Testing on Seismic Performance of Inclined Tripod Micropiles

Abstract

This study evaluates the seismic performance of inclined tripod micropiles through physical modeling. A dynamic centrifuge model test examined the effect of inclination angle from 0° to 30° on the dynamic behavior of micropiles against seismic loads. The physical modeling results showed that the inclined micropiles exhibited better seismic performance than the vertical micropiles. The horizontal displacement and acceleration at pile heads decreased as the installation angle increased, but with minimal difference between 15° and 30°. The vertical displacement was the least at the 15° pile. The near-surface bending moments of the 15° and 30° piles were significantly less than that of the 0° pile. The presented results suggest that an installation angle of 15° is expected to be a proper choice for inclined micropile design for a limited space usage.