Parametric Study on Analysis and Design of Permanently Anchored Secant Pile Wall for Earth Quake Loading

Abstract

Due to space limitations in urban areas, deep excavation in to the ground has become a common practice worldwide. Deep excavations are supported by conventional retaining walls: sheet pile walls, braced walls, diaphragm walls and secant pile walls. An advantage of secant pile wall compared with other excavation supporting systems is that they are the most economical methods of creating an effective water control barriers for building structural walls. The analysis of these deep excavations requires considerations of; nonlinear, dynamic and involves consideration of soil parameters, deformation, interaction of soil and retaining configuration. Thus, in order to accurately describe the behaviour of the anchored secant pile for earthquake loading, 3D finite element simulation was applied. The study considering earth pressure, plastic analysis, and soil deformation was carried out. The analysis indicated that for 20 m excavation step in fourth stage, incremental lateral displacement was 55.2 mm and total displacement was 110.4 mm. The analysis indicated that the deeper the foundation, the larger the deformation. The real accelerogram of Loma Prieta earthquake at Del Valle Dam Station with moment magnitude 7.1 occurring at epicentral distance 66 (18 Oct, 1989) was used in the study. In order to accurately study the response of the anchored secant pile to earthquake loading; it is suggested to carry out the relevant tests to determine the right stiffness parameters. Further investigation on parameters (density and shear modulus) and other conditions that affect seismic analysis.