A review of design methods for retaining （回顾支护的设计方法）.pdf

A review of design methods for retaining structures under seismic loadings C. Visone F. Santucci de Magistris Structural and Geotechnical Dynamic Lab StreGa, University of Molise, Termoli (CB), Italy ABSTRACT: The earth retaining structures frequently represent key elements of ports and harbors, transpor- tation systems, lifelines and other constructed facilities. Earthquakes might cause permanent deformations of retaining structures and even failures. In some cases, these deformations originated significant damages with disastrous physical and economic consequences. For gravity walls, the dynamic earth pressures acting on the wall can be evaluated by using the Mononobe-Okabe method, while Newmark rigid sliding block scheme is suitable to predict the displacements after the shaking, as demonstrated by several experimental tests. Instead, this simplified approach is not very useful for embedded retaining walls for various reasons. Many researchers are interested to this topic. Advanced numerical analyses, centrifuge modeling, in-situ monitoring of full-scale model are the main developing research activities on this subject. Here, after a brief review on the fundamen- tal seismic earth pressures theories, the application of the pseudostatic approach to the analysis of embedded retaining walls, as prescribed by the European Codes, is highlighted. Finally, some considerations on the cer- tain limitations of this approach is done and the indications given by the latest Italian Building Codes (D.M. 14/01/2008) are summarized. 1 INTRODUCTION. improvements contained in the latest Italian Building Codes are recalled. Embedded walls are relatively thin walls of steel, reinforced concrete or timber, supported by anchor- ages, struts and/or passive earth pressure (EC7-1, 2 MAIN SEISMIC EARTH PRESSURES 2002). T