为研究水下爆炸载荷的概率密度，选取炸药密度、水密度作为随机变量，基于乘同余组合发生器，利用Fortran语言编写随机数生成程序，产生100组随机变量的样本；采用有限元程序LS-DYNA对水下爆炸冲击波进行仿真计算，得到冲击波的峰值压力；并检验其是否服从正态分布，验证最大熵法程序的正确性，采用最大熵法拟合其概率密度函数，研究爆炸载荷的统计规律，得到不同爆距，不同时刻的冲击波峰值压力的概率密度。该方法可较好地解决爆炸载荷的随机数理统计模型，为进一步进行结构的可靠性分析提供理论依据。
In order to study probability density of underwater explosion load, density of explosive and density of water are considered as basic random variables. 100 samples of random variables are obtained using the Fortran program by which random numbers could be generated. The simulation of underwater explosion load is carried out by LS-DYNA, peak pressure of shock wave is obtained and verify whether it obey the normal distribution. Verify the correctness of the maximum entropy method, maximum entropy method is used to fit the probability density function of the peak pressure in different blast distance and different time. The method can be used to solve the random statistics model of explosion load, and it can provide the theoretical basis for the reliability analysis of the structure.
2017,39(9): 12-16,22 收稿日期：2016-11-01
DOI：10.3404/j.issn.1672-7649.2017.09.003
分类号：O38
基金项目：国家自然科学基金资助项目（51509113）；江苏省高校自然基金资助项目（16KJA580003，14KJB580005）；江苏省重点实验室开放基金资助项目（CJ1403）
作者简介：张婧(1983-),女,博士,副教授,研究方向为爆炸力学。
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