关键词: 桩板式抗滑挡土墙, 振动台试验, 动力响应, 抗震设计

Abstract: From the investigation of seismic hazards of subgrade in Wenchuan earthquake, the anti-sliding sheet pile wall has been proven to be an excellent seismic structure in bedding or accumulation slopes. In order to understand the seismic performance better and optimize the seismic design, large shaking table test is performed. In order to ascertain the seismic response characteristics of anti-sliding sheet pile wall, acceleration histories recorded at Wolong station in Wenchuan earthquake are scaled and used to excite the model. The test results reveal the distribution pattern of earth pressure along the pile, seismic response of displacement and accelerations in slopes under ground shaking. The research demonstrates that the distribution of seismic earth pressure is nonlinear along the pile; and vertical seismic load has amplification effect on horizontal acceleration. Therefore, the seismic earth pressure under bidirectional loads is larger than that under unidirectional horizontal load. However, the difference between them is not obvious in seismic zones of basic intensity VII and VIII. Furthermore, landslide thrust, soil resistance of sliding bed, and displacement of pile are proportional to the input seismic peak acceleration. It means that, with the increase of input peak seismic acceleration, the amplification ratio of acceleration increases and the material shear strength of sliding surface reduces. The landslide thrust, soil resistance and pile displacement increase; and the increment rates become larger. In addition, based on the test results, reasonable values of seismic coefficient Cz are proposed for the structure; and the values of Cz are 0.2, 0.35 and 0.4 in the seismic zones of basic intensity VII, VIII and IX respectively. The test results are helpful to reveal the seismic mechanism and can provide reliable basis for seismic design of anti-sliding sheet pile wall.

Key words: anti-sliding sheet pile wall, shaking table test, dynamic response, seismic design