飞机荷载作用下超载预压软土地基的长期沉降

Long-term settlement of surcharge preloading foundation in soft clay area induced by aircraft loads

为了研究超载预压地基在飞机荷载作用下的长期沉降,通过对温州淤泥质黏土进行室内循环三轴试验,建立饱和软黏土的累积塑性应变模型和累积孔压模型.利用层状弹性理论计算地基中的动偏应力,结合已建立的经验模型得到在交通荷载作用下软土地基的累积塑性应变和孔压消散应变.采用分层总和法计算飞机荷载作用下温州机场跑道超载预压地基的长期累积沉降,将计算沉降值与实测沉降值进行对比,验证了饱和超固结土不排水累积塑性应变模型和累积孔压模型的合理性.

Cumulative plastic strain model and excess pore pressure model were proposed by cyclic triaxial tests conducted on Wenzhou soft clay in order to analyze the long-term settlement of surcharge preloading foundation under aircraft loads. Combining with the dynamic deviator stress calculated by multilayer elas- tic theory and the established experience model, the cumulative plastic strain and the strain induced by pore pressure dissipation of the soft ground under traffic loading were obtained. The long-term sediment of the pre-loaded lane of Wenzhou airport under the airplane loading was calculated by summation of sub-lay- ers and verified with the in-situ test results. Then the reasonability of the undrained cumulative plastic strain model and the cumulative pore pressure model of over-consolidated soil was validated.