结构自重及摩擦系数作变量对直立式防波堤可靠度的影响*

在直立式防波堤的抗滑、抗倾可靠度分析中，通常将结构与基床间的摩擦系数f，直立式防波堤在水中的重力G及其引起的稳定力矩MG均作为定值处理，而忽略三者的变动对可靠度的影响。以秦皇岛港燃料油基地的直立式防波堤为例，采用JC法、映射变换法及Monte Carlo模拟3种方法分别计算了摩擦系数f，自重G及其引起的稳定力矩MG作为定值和变量时直立式防波堤抗滑、抗倾的可靠性指标。结果表明：将摩擦系数f，自重G及其引起的稳定力矩MG均作为变量处理，得到的可靠性指标更精确、更符合实际情况；摩擦系数f的变动对直立式防波堤的可靠度影响较小，而自重G及其引起的稳定力矩MG二者的变动对直立式防波堤的可靠度影响较大。

Impact of structure self-weight and friction coefficient as variables to reliability of vertical breakwater

In the vertical breakwater reliability analysis,f,the friction coefficient of structure and the foundation bed,G,structure’s self weight,MG,the moment of stability induced by G,are often taken as constant values.But their impacts on the calculation results should not be ignored.Taking the breakwater in Qinhuangdao as an example,we verify the impact of structure’s weight and the friction coefficient taken as variables to the breakwater’s reliability.The JC method,mapping transformation method and Monte Carlo simulation method are used to calculate the reliability of the breakwater while f,G,MG are taken as constant value or variables.It is concluded that to take f,G,MG as variables is more reasonable.The variation of f makes little impact on the reliability calculation results,while the variation of G and MG makes much.