Seismic behavior of tiedback retaining walls.

Abstract

Tied-back retaining walls frequently fail during earthquakes. Such failures are usually characterized by large displacements of the retaining wall and subsidence of the backfill. Often these failures result in extensive damage to the tied-back wall system and to adjoining structures and lifeline facilities. Whereas the seismic behavior of gravity retaining walls has been investigated in detail and procedures are now available for the seismic design of gravity retaining walls, very little analytical or experimental work has been reported on the behavior of tied-back retaining walls when they are subjected to seismic loads. In this research, a limit equilibrium method is used to analyze the seismic behavior of tied-back retaining walls. The analytical approach is calibrated against results from shake table tests on aluminium walls retaining a dry cohesionless soil. The shake table experiments were performed at the State University of New York at Buffalo seismic simulator facility. The analytical and the experimental study indicate the tremendous influence of anchorage systems on the performance of tied-back retaining walls during earthquakes. Based on the results of these studies, a procedure is proposed for the design of tied-back retaining walls in seismically active regions. The main thrust of the proposed seismic design procedure is in improving the anchorage capacity of tied-back retaining walls.