土工离心模型的空间变异性研究

Performance of a geotechnical centrifuge model is controlled by the spatially averaged soil properties in the model. In this paper, the spatial variability of soil properties in geotechnical centrifuge models is investigated based on the theory of random field. The scale of fluctuation of soil density and porosity of two centrifuge models are estimated using the autocorrelation function method. The similarity of spatial variability between a model and its prototype is also studied. It is found that the point coefficients of variation in centrifuge models are slightly smaller than those in field. The scale of fluctuation in centrifuge models is much smaller than that in field. It is also found that the spatially averaged coefficients of variation are different for the centrifuge models with different size, which are designed to simulate the same prototype. In this paper, a contour plot of the spatially averaged coefficients of variation is provided. One may control the point coefficient of variation and the scale of fluctuation of the soil in a centrifuge model in order to achieve a design spatial averaged coefficient of variation for the corresponding prototype.