吸力式沉箱基础考虑土体流变效应的p-y曲线法

A p-y curve method for suction caisson foundation considering soil rheological effect

为了考虑土体流变效应对吸力式沉箱基础承载特性的影响,通过建立理想弹塑性p-y曲线法中土抗力系数与时间变量之间的关系,提出了一种考虑土体流变效应的吸力式沉箱基础长期性能分析方法.基于2组不同水平荷载作用下的长期模型试验,采用Matlab拟合土体参数试验数据,获得关于时间变量的理想弹塑性p-y曲线模型,并采用该方法对模型试验结果进行分析.结果表明:在长期模型试验中位移与土压力发展主要集中在试验前期,后期位移与土压力稳定需要更长时间,土体流变效应较为明显.理论计算值与实测值随时间变化规律类似,理论计算结果与试验结果相差8%左右,说明长期水平荷载下考虑时间因素的p-y曲线计算结果能较好地吻合试验值.

To consider the soil rheological effects on bearing characteristics of the suction caisson foundation,a long-term performance analysis method for considering the soil rheological effect of the suction caisson foundation is proposed by establishing the relationship between soil resistance coefficients and time variable of the ideal elastic-plastic p-y curve method. Based on two sets of different long-term horizontal load model tests,the ideal elastic-plastic p-y curve model about time variable is obtained by using Matlab to fit the experimental data of soil parameters. Then,the proposed method is used to analyze the results of the model test. Analysis results show that in the long-term model test,the development of displacement and soil pressure are mainly concentrated in the early stage of the experiment; the later displacement and the soil pressure stabilization need longer time,and the soil rheological effect is obvious. The theoretically calculated values and the measured values are similar with the change of time,and the difference between them is about 8%,which show that the calculated results by this method can fit well with the experimental values.