Geotechnical and Seismic Considerations in the Design of Highway Embankments

Abstract

The paper presents the various geotechnical considerations in the design of high embankments and focuses on the most common stability analysis procedure. The embankment stability analysis model should best represent the site subsurface condition, properties of fill, and applied loads. Slope stability analysis using computer programs based on limit equilibrium and finite element approach for a two-dimensional model is utilized. Seismic analysis to evaluate long-term stability of slopes and embankments is carried adopting earthquake-resistant design through the selection of appropriate ground motion parameters using pseudo-static method. Two approaches to obtain peak ground acceleration values used in the Philippines and various references in selecting seismic coefficient for pseudo-static analysis are presented. Furthermore, a case study is presented to establish the importance of selecting a rational seismic coefficient, with the ultimate aim of coming up with cost-effective design.