船舶结构概率损伤容限分析

Probabilistic Damage Tolerance Design for Ship Structural Components

损伤容限设计是一种先进的现代设计思想，为了使这种设计建立在可靠性分析的基础上，根据概率断裂力学理论，分别建立了具有裂纹型初始缺陷结构和受损结构在裂纹扩展中结构疲劳寿命及其可靠性估算的动态模型．在给出了结构设计参数的分布函数后可求得一组与结构初始损伤、结构使用年限和剩余寿命、设计应力等有关的动态可靠性曲线，由此可获得保证一定可靠度的结构的损伤容限，并在设计时选取具有给定可靠度的各种设计参数，或给定设计参数后估计所设计结构的可靠度．

Damage tolerance design is an advanced modern design method. Based on analysis of structural reliability, a reliability estimating dynamic model of structures with initial imperfection of crack type and damaged structures is established according to a probabilistic fracture mechanics theory. With the distribution functions of structure design parameters, we can find a series of dynamic reliability curves which are relative with the structural initial damage, service year, residual life, design stress. Thus, the damage tolerance and the other design parameters can be determined according to the request of reliability. The structure reliability can also be estimated when the design parameters are given.