LARGE-SCALE SHAKING TABLE TESTS STUDY OF SEISMIC DISPLACEMENT MODE OF RETAINING STRUCTURES UNDER EARTHQUAKE LOADING
WEN Changping1，2，YANG Guolin1
(1. School of Civil Engineering and Architecture，Central South University，Changsha，Hunan 410075，China；2. College of Civil Engineering and Mechanics，Central South University of Forestry and Technology，Changsha，Hunan 410004，China)
Abstract：Two slope models with the geometric scale of 1∶8 were designed and two large-scale shaking table model tests were performed to study the seismic displacement modes，its characteristics and aseismic behavior of four retaining structures including gravity retaining wall，sheet-pile retaing wall，anchor lattice frame structure and prestressing anchor lattice frame under seismic loading and in three excitation directions including X-，Z-，and XZ- direction respectively. The results show that：(1) In X direction or XZ-direction excitation，the seismic permanent displacements of gravity retaining wall and sheet-pile retaining wall are negligible at the peak excitaion acceleration AXmax≤0.4 g. In Z-direction excitation，the seismic permanent displacements of sheet-pile retaining wall and prestressing anchor lattice frame are also negligible. (2) In X-direction excitation and at AXmax＞0.4 g，the seismic displacement mode of gravity retaining wall is the slide-based coupling of the sliding to filling soil mass and the rotating inward about base，and the seismic displacement mode of sheet-pile retaining wall is the sliding to filling soil mass. In Z-direction excitation and at the peak excitation acceleration AZmax＞0.267 g，the seismic displacement mode of gravity retaining wall is the coupling of the sliding to filling soil mass and the rotating inward about base. In XZ- direction excitation and at AXmax＞0.4 g，and AZmax＞0.267 g，the seismic displacement mode of gravity retaining wall is the rotation-based coupling of the sliding to filling soil mass and the rotating outward about base，and the seismic displacement mode of sheet-pile retaining wall is the slide-based coupling of the sliding from filling soil mass and the rotating outward about base. (3) In X- or XZ- direction excitation，the seismic displacement mode of prestressing anchor lattice frame is the translation of outward and lower of the slope and same as that of anchor lattice frame structure. In Z- direction excitation and at AZmax＞0.267 g，the seismic displacement mode of the translation of outward and upper of the slope of anchor lattice frame structure is gradually transformed into the translation of inward and upper of the slope. (4) The aseismic performance of sheet-pile retaining wall is better than that of gravity retaining wall at X- or Z- direction excitation，but poor than that of gravity retaining wall in XZ- direction excitation. The aseismic performance of prestressing anchor lattice frame is better than that of anchor lattice frame structure at X-，Z-，and XZ- directions excitation.
2011, Vol. 30 
