Abstract Database


Supervisor: Masahito TAMURA, Masanori HAMADA
Country: Costa Rica

The behavior of retaining structures and pile foundations during the action of dynamic forces, such as earthquakes, is a complex subject; serious damage on these structures had been found due to earthquakes.  Large displacements, which can occur during or after earthquakes, are one of the most relevant aspects that determine the performance of retaining structures or its damage.

The scope of this work is to study earthquake induced displacements on this structure for liquefiable and non-liquefiable soil in the backfills, focused on the point of view of the experimental analysis, review of damage cases, and theoretical approaches. 

Studies include soil survey testing at the OYO Corporation, mainly the surface wave method test for determining the field properties of terrain and retaining walls; the study of Genkai Island damage on Stone retaining walls during the 2005 Fukuoka Oki Earthquake using a finite element program developed by Dr Wakai at the Gunma University; here parametric analysis of wall stiffness, wall and backfill geometries was performed and the existing damage explained

For liquefiable backfills, lateral spreading can occur with the movement of the retaining structure; this phenomenon has caused great damage on Niigata prefecture civil structures in 1964 Earthquake.  This condition is evaluated from actual techniques based on databases and centrifuge testing (Hamada Laboratory, Waseda University, OHBAYASHI Corporation centrifuge machine); here, discussion is regarding the estimation of total damage area behind the wall and the possibility of flow or no flow of the terrain behind the wall after the wall movement.

Also, the objective of the work is also to review and check the actual design considerations for this kind of structures according to Costa Rica’s seismic and foundation codes against the seismic action.  This is important as the techniques and considerations analyzed are useful tools for design according to the performance philosophies, and also to reduce the vulnerability of retaining walls to earthquakes; which is important as this structure is support of important structures in ports, bridges, roads and residence.