Shaking Table Test and Numerical Simulation of Free Field in Sand-Sawdust Mixed Soil

The sand-sawdust mixture has been frequently used in the shaking table test because it is easy to adjust the shear wave velocity of model soil by changing the sawdust content. In this paper, the dynamic properties and the seismic responses of the free field in sand-sawdust mixture as well as the boundary effects of the laminar shear model box were investigated using a series of shaking table tests. The influences of different constitutive models on to the seismic response analysis of the model soil were studied by comparing the numerical results with the experimental results. The comparison shows that the boundary effect mainly influences the model soil within 0.75 times of the soil depth from the box boundary and the impact decreases with the increasing of soil depth. The natural frequency and acceleration amplification factor of the field decrease with the increasing amplitude of the ground motion. The comparison of the seismic response results for different constitutive models of the Hardin-Drnevich, Ramberg-Osgood, and Davidenkov models using the one-dimensional equivalent linearization method indicated that the combination of Davidenkov and Hardin-Drnevich model could improve the accuracy of seismic response for sand-sawdust mixed soil.