The Research On The Deformation Behavior In Soft-soil Foundation Under Embankment By Laboratory Model Test And Settlement Prediction

There are two parts in this paper . The first part studies the deformation behavior of soft soil under embankment by laboratory model test. In the tests, we mainly considered a few factors, such as depth of soft soil, the magnitude and rate of loading, and its slope angle etc, which effected on the deformation of soft-soil foundation. The test results showed that the maximum lateral deformation of homogeneous soft soil appeared in 2~7 meters underground. So, we consider that the method, which depends on the lateral deformation values of surface observation pile to control the stability of soft-soil foundation during construction, is unreasonable. The test also indicated that soft-soil foundation could still support larger load after the initial failure of soft-soil foundation had been occurred. This offers the basis of the construction of "Impelling Failure method" in soft-soil foundation.The second part studies the methods of settlement prediction. Because there are many factors that effect on the settlement of soft soil, furthermore the relationship between time and settlement is very complicated, in this paper we adopted the method that called the prediction method of multi-model, and introduced a new kind of predictive model-Compertz Curve Equation . At the same time, we proposed that the mean square errors of the last 5 numbers between the measured results and predicting results were used as the criterion that could judge the optimum model while we compared and analyzed several models; we also compiled some programs for calculating. Finally, by comparing with the predicting results of 5 engineering examples, the prediction results of Compertz Curve Equation are proved to be better and more stability than other methods, and the prediction method of multi- model is feasible.