Incremental model for pore water pressure and its applicability in centrifuge modelling

The centrifugal model test is an increasingly mature and widely-used physical test method. However, there is few researches on the constitutive relationship, and the researches on the constitutive relationship under the real stress and boundary conditions of the centrifugal model test have more obvious advantages. Based on the basic idea of Ishibashi multiplication of various factors, an incremental model for pore water pressure suitable for the arbitrary load and anisotropic consolidation is proposed. The applicability and reliability of the new incremental model with the test data of the DSP-II transducer is verified. The results show that the incremental model can well describe the development process of the pore water pressure of saturated sand and the liquefaction threshold under different seismic loads, relative densities and soil depths. The liquefaction resistance and the relevant parameters of saturated sand with different densities are given. With the decrease of the cyclic dynamic stress ratio of saturated sand, the initial liquefaction trigger vibration cycle time N increases gradually. With the increase of the relative density D_r of saturated sand, the liquefaction resistance also increases. The predicted data of liquefaction resistance calculated by the incremental model are basically consistent with the measured ones, which can better predict the liquefaction resistance of saturated sand in centrifugal model tests.