爆炸载荷作用下弹性结构动力可靠性研究

Dynamical relability of an elastic structure subjected to explosion

为研究随机爆炸载荷对弹性结构安全性影响,基于有限体积法(FVM)提出一种爆炸载荷作用下弹性结构动力可靠度计算方法。基于FVM的控制方程推导出响应量对基本随机变量偏导的显式求解方程;将响应量在随机变量均值点处进行泰勒展开,略去高阶项,并在展开式两端同时取均值和方差求得响应量的均值和方差等数字特性;在此基础上利用一次二阶矩法求解结构可靠性指标。为证明该方法的可行性,以炸药装药量、爆距及结构屈服应力作为基本随机变量,计算固支板在远场爆炸载荷作用下的可靠度,并分别与响应面法和蒙特卡洛法进行对比,结果表明该方法具有较高的效率和精度,能为工程实践提供参考。

To study safety performance of an elastic structure subjected to random explosion load, based on finite volume method （FVM）, a numerical method to calculate structural reliability index was presented. The partial derivatives of responses with respect to basic random variables were obtained with the governing equation of FVM. Then, the mean values and variances of responses were attained based on Taylor expansion, and the structural reliability index was calculated with the first-order second moment method finally. To prove the feasibility of this method, taking explosive engineering practice effectively.