ABSTRACT
This paper presents the assessment of the adequacy of a Mechanically-Stabilized Earth (MSE) wall, reinforced with steel geostraps, for a bridge approach within Metro Manila, located few kilometers away from the active West Valley Fault (WVF). Performance of the MSE Wall under static and seismic conditions were assessed using two approaches: (1) Limit Equilibrium Method (LEM) by GLE/Morgenstern-Price Method; and (2) Deformation Analysis by Finite Element Method (FEM). The study demonstrates that while inadequate factors of safety under seismic loading may be obtained using LEM, earthquake-induced deformation values are found to be within tolerable limits for lower-hazard design levels. It was also established that designing the geostrap reinforcement to fully withstand higher-hazard ground motions may be uneconomical for the available wall material. Nevertheless, cost-effectiveness of the design may also be achieved by allowing some deformation to the structure in case of higher-level earthquakes, while maintaining serviceability in keeping with current seismic design philosophy.
