The Investigation and Examination of Single Pile and Pile Group under Seismic Loading

Document Type : Original Article

Authors

Faculty Member, Department of Civil Engineering, Ayatollah Borujerdi University, Iran.

Abstract

One of the important lateral forces is dynamic loading due to earthquake. The behavior of pile foundations under earthquake loading is an important issue that widely affects the performance of structures. The topic of seismic pile behavior has been covered extensively in the literature over the past few decades. In this paper the behavior of single pile and pile group have been examined. Pile group has four piles and rebar and concrete weight in pile group is equal to single pile in this research. The single pile and pile group are analyzed under Tabas, Bam and Loma-perita earthquakes loading. The finite element software, ABAQUS, is utilized to model pile and piles group. Soil is modeled as an elastic-perfectly plastic model using the Mohr–Coulomb constitutive model. The side boundaries are constrained against horizontal direction and the bottom boundaries are constrained against both horizontal and vertical directions. Maximum shear force, lateral displacement and force along the pile in single pile and pile group, under the earthquake loading that mentioned above, have been measured. The results are shown the settlement in pile group is around 30 percent less than single pile and the lateral displacement in the head of single pile is 0.23 meter but the lateral displacement in group pile is 0.1 meter in Bam earthquake loading. The shear force in the head of single pile is 2084 kN and the shear force in head of the pile in pile group is 334 KN. Taking into account soil condition, the results shown that utilize the pile group (equal rebar and concrete weight by single pile) is better and more economic than single pile.

Keywords


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