波流作用下导管架平台桩基冲刷试验研究

Experimental Study of the Pile Foundation Scouring of Jacket Platform under the Effect of Wave and Current

海洋导管架平台桩基冲刷受到环境条件(波浪和海流)、桩径大小和海床表面土体复杂特性条件影响,现场分析极其困难。现有各种桩基冲刷计算理论均建立在一定的简化假设基础上,与实际桩基冲刷状况存在一定程度上的偏差。以JZ20-2MUQ型导管架平台为原型做缩尺模型试验,与理论分析相比,能够更加真实地模拟出桩基冲刷现象以及形成的冲刷坑形态和大小。利用试验测量数据研究了各影响因子对桩基最大冲刷深度的影响,且用Origin数据分析软件对各影响因子的数据进行准确拟合处理,得出导管架平台桩基冲刷在粘土条件下最大深度非线性回归公式,该公式概念清晰,具有很好的实用性,可为基于冲刷的导管架平台桩基设计提供科学依据。

The offshore jacket platform pile foundation is subject to the effect of complex conditions, such as environmental condition （mainly wave and current）, pile diameter size and seabed surface soil. Therefore, the field analysis is very difficult. All calculation theories available concerning pile foundation scouring are based on a certain simplified hypothesis, which indicates some deviation from the practical pile foundation erosion. Model JZ20-2MUQ jacket platform is taken as the prototype to conduct the scale model test which, compared with the theoretical analy- sis, can make a more realistic simulation of pile foundation erosion as well as erosion pit profile and size. The test measurement data were used to study the effect of the influencing factors on the maximum depth of pile foundation scouring. The ORIGIN data analysis software was used to carry out the accurate fitting treatment of the data of the influencing factors. The nonlinear regression formula for the maximum depth of the jacket platform file foundation scouring in the condition of clay was derived. The concept of the formula is explicit with desirable practicality, pro- viding the scientific basis for the design of pile foundation.