关键词: 边界效应, 层状剪切模型箱, 振动台试验, 土-结构动力相互作用, 三维地震动

Abstract: Shaking table test is considered as an effective tool for investigation of soil-structure interaction problems and validation of research methods under earthquake loading. It is essential to choose an appropriate soil container, because the soil container directly affects the boundary of the model and the accuracy of the simulation. A 3D circular laminar shear container is deployed consisting of 19 layers of aluminum alloy frames with dimensions of 1 800 mm in height and 4 500 mm in diameter. The upper and lower layer frames are connected by supports in three direction. In order to investigate the boundary effect of the laminar shear container on the seismic response, a shaking table test is conducted to acquire the test data from accelerometers embedded in the sand bed at various depths and distances from the edge of the container. In the shaking table test, the ground acceleration corresponding to design spectra of AP1000 nuclear power plant is applied as the input for earthquake ground motion. The acceleration time-histories compare with response spectra at different monitoring points. The relative error of PGAs and response spectra recorded at monitoring points from center to the edge of the container are calculated. It is shown that the designed 3D laminar shear container could effectively simulate the infinite boundary condition of actual site in three directions, which overcomes the shortcoming of the former laminar shear container inputting one-direction or two-direction excitation.

Key words: boundary effect, laminar shear model container, shaking table test, soil-structure interaction, 3D earthquake ground motion