A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Engineering and Technology

Thesis (M.Eng.) - Asian Institute of Technology, 1986

A seismic study of the proposed Liyutan Dam, a zoned earth-rock fill dam in Taiwan, is presented, based on the actual material behavior and state-of-the-art dynamic analysis. A maximum credible and a design basis earthquake with a peak acceleration of 0.77g and 0.4g were used, respectively. The static stresses prior to the earthquake were determined by the computer program ISBILD whereas the dynamic analysis was carried out by FLUSH . The dam is modeled as a plane strain system. Soil-structure interaction effects are modeled by including a part of the massless foundation in the finite element model (kinematic interaction) and hydrodynamic interaction effects are approximated by an added mass. The horizontal input motions are considered. The dam is analyzed for full reservoir condition only . One portion in the upstream shell of the dam is expected to be built up from silty sand which is vulnerable to liquefaction. This material is investigated using dynamic triaxial tests. Based on these material properties, an approximate permanent deformation analysis after Lee is carried out. The experimental investigation shows that parts of the silty sand forming the upstream shell have high liquefaction potential under the earthquakes considered, but the permanent deformation analysis does not show any failure phenomenon .