关键词: 前期固结压力, 非参数化拟合, 参数化拟合, 三次平滑样条曲线, 最大曲率点

Abstract:

Soil preconsolidation pressure is an important index for determining the consolidation status. The foundation settlement calculation formulas are different as on various consolidation statuses, so it is very significant to determining preconsolidation pressure precisely. First the imperfectness of normal parametric models for determining the max curvature point of the fitted e-lg(p) curve is analyzed; then the cubic smoothing spline which is a nonparametric model used for fitting is proposed; the calculation results show that this model is more adaptive to experimental data and the fitting result is more precise. Base on the Casagrande’s method of determining the preconsolidation pressure, the corresponding program “PCP Calculation” is then developed by MATLAB; the program has a friendly interface and can draw figure exactly; and the calculated results are satisfactory.

Key words: preconsolidation pressure, nonparametric fitting, parametric fitting, cubic smoothing spline, maximum curvature point