动静载荷试验法荷载-沉降曲线分析方法研究

Analytic Method of Load-settlement Curve in Statnamic Load Testing

为将准静荷载试验法中动态荷载-沉降曲线转换为静态荷载-沉降曲线,并尽量与工程实际相接近,对已有分析方法进行了适用性探讨和分析比较,在原有理论基础上提出了新的C模型分析方法,将整个试验过程中桩-土系统的阻尼系数按照理论前提随时间变化分为3段,各段分别计算,最后组合成随时间变化的阻尼系数曲线。然后根据单质点模型的平衡方程计算出静态P-S曲线。借助大型计算软件MATLAB,对具体工程实例分别采用已有方法与C模型法分别进行编程计算。计算结果表明:C模型法计算出的静态P-S曲线处于由卸载点法和起始刚度法得出的静态曲线之间,该方法能较合理地分析准静载荷试验法的荷载-沉降曲线。

In order to convert the dynamic loadsettlement curve in statnamic load testing to a static load-settlement curve and make it as closely as possible to the practice,the existing methods were analyzed and compared.Based on the existing theory,a new C model method were proposed,in which in accordance with the theoretical premises the damping coefficient of the pile-soil system was divided into three sections during the whole course of the experiment,each section was calculated separately and finally combined into a damping-time curve,then the static P-S curve was calculated based on the equilibrium equations of single-particle model.By using MATLAB,a specific project example was calculated separately by two existing methods and the C model method.The results show that the static P-S curve calculated by C model method lies between the other two curves which derived from the unloading point method and the initial stiffness method,and the C model method is able to analyze P-S curve in statnamic load testing reasonably.