钢悬链线触地区管土作用模型试验

Experimental research on pipe-soil interaction of touchdown zone on steel catenary riser

针对立管触地区疲劳寿命预测时摩擦系数选取存在随机性导致计算结果不准确,从而对立管安全性估计不足的问题,配置了5种粒径分布不同的土壤,制作了6种不同尺寸参数的立管模型,通过测量及分析计算得到立管模型与海底土壤之间的摩擦系数。对600组结果进行统计分析,得到摩擦系数大小与土壤有效粒径及摩擦系数的变异系数与土壤有效粒径的关系,并绘制出摩擦系数范围曲线,为今后预测立管触地区疲劳寿命提供准确依据,同时为立管相关计算提供参考。结果表明:立管与海底土壤之间的滑动摩擦系数随着土壤的有效粒径增大而增大;立管与土壤之间滑动摩擦系数的变异系数随着土壤有效粒径的增大而减小。

According to the circumstance that the coefficient used to calculate the frictional resistance is random,thus causing the inaccuracy of calculation and prediction on fatigue life and underestimating the safety of riser,five typical soil samples with different particle distributions and six riser models with different diameters in the present paper were designed.The experiment was conducted and calculation was made to measure friction coefficients and over 600 sets of experiments data were obtained for statistical analysis to find the influence of the effective size of soil particle on quantity of friction coefficient and variation coefficient of friction coefficient.The coefficient range curve was also given to provide better accordance to predict the fatigue life of touchdown zone and give reference on the relevant calculation on the riser.The results show that the sliding friction coefficients grow larger with the increase of the effective size of soil particle and the variation coefficients of sliding friction coefficient become smaller with the growth of the effective size of soil particle.