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关于筑立在中密石英沙层中小型三腿原型自升式钻井平台在周期性荷载作用下的位移与孔隙压力的响应问题，我们用不带裙边的平板底座进行了位移对周期荷载响应和用带裙边的平板底座进行了孔隙压力对周期性荷载响应的两种离心机试验。结果表明，两种底座均有非常高的基础固着性，在裙边无破裂的情况下，裙边的存在会少许削弱整体平台结构在动态情况下的稳定持久性（指由于底座在基土中植根过固，绝少松动，则必对平台结构的受力不能起到缓冲作用，于是平台结构所受的外力概由自身应力抵抗，久而必致疲劳——译者）。通常，带裙底座的沉陷量比不带裙底座的要小。在异常情况下，带裙基础能表现出较大的抗拔能力。孔隙压力的响应是非常复杂的，出现了双频与单频的分量。一般地，响应曲线峰值与谷值的相位与底座载荷频率均不相同。孔隙超静水压力的幅度取决于载荷的大小、周期载荷频率以及在泥土中的位置。正负孔隙压力的幅度不对称。最大负压在某些施力周期里发生。孔隙压力的消散时间也取决于载荷的大小，不同的载荷对应于不同的孔隙水压曲线。大量的工作是证实和归纳这些结果，以便将其外推到大型平台上。不同的平台具有不同的“身长——支腿”，相对空间比例和底座直径；且其所处海底沙体的矿物成分、密度?
With respect to the problem of displacement and pore pressure response of a medium and small-sized three-legged prototype jack-up drilling platform under medium-density quartz sand stratum, we carried out displacement response to cyclic loading using a flat base without skirt And two centrifuge tests of pore pressure response to cyclic loading were carried out with a skirted skirt base. The results show that both foundations have a very high degree of basic fixity, and the presence of skirts will slightly diminish the stability of the overall platform structure under dynamic conditions without rupture of the skirt (referring to the fact that the base is in the soil Rooted solid, rarely loose, you will not be able to play a buffer role in the platform structure of the force, so the external forces suffered by the platform structure by its own stress resistance, fatigue will be long. In general, the amount of sinking of the skirt base is less than that of the skirtless base. In exceptional circumstances, with skirt foundation can show greater anti-pull ability. The response of pore pressure is very complex, with the appearance of dual-band and single-band components. In general, the response curve peak and valley phase and base load frequency are not the same. The magnitude of pore hydrostatic pressure depends on the size of the load, the periodic loading frequency, and the position in the soil. Positive and negative pore pressure amplitude asymmetry. The maximum negative pressure occurs during some force cycles. Pore pressure dissipation time also depends on the size of the load, different loads correspond to different pore pressure curves. A great deal of work is to validate and summarize these results so that they can be extrapolated to large platforms. Different platforms have different “body length - legs”, the relative space ratio and base diameter; and the mineral composition and density of the sand body of the sea floor where it is located?