自升式钻井平台桩靴贯入饱和砂土的机制研究

为研究桩靴贯入饱和砂土的承载机制以及桩靴周围砂土变形机理，开展桩靴的抗压承载土工模型试验以及桩靴-土体相互作用的透明土试验，测得了桩靴荷载-沉降变化规律、桩靴周围砂土的位移向量场和等值线图，初步探讨了桩靴贯入饱和砂土时的承载机制与桩靴周围砂土变形机理。基于圆孔扩张理论及分段位移迭代算法，推导出静载作用下桩靴荷载-沉降变化规律；与试验结果的对比发现：计算误差约为11.7%。通过浅应变路径法(SSPM)计算得到桩靴周围土体位移理论值；与试验结果对比发现：计算误差在16.7%～26.3%。

RESEARCH ON MECHANISM OF JACK-UP DRILLING PLATFORM SPUDCAN PENETRATING INTO SATURATED SAND

In order to study the bearing characteristics of spudcan and the deformation mechanism of sand around the spudcan when the spudcan penetrated into saturated sand, model tests of bearing capacity of spudcan as well as transparent soil experiments of spudcan-soil interaction were carried out. The load-settlement curves of spudcan, displacement vector field and contour map of sand around the spudcan were obtained. According to the cavity expansion theory and segmental displacement iterative algorithm, the load-settlement curves of spudcan under static load was also derived, the error of which was about 11.7% compared with the test results. The theoretical displacement of soil around the spudcan was calculated using the shallow strain path method (SSPM). Compared with the test results, it is found that the calculation error was between 16.7% and 26.3%.