动荷载作用下预测玻璃板破坏强度和破坏时间的一种改进模型--Ⅰ．理论

摘要

Considering the randomness and the growth of cracks,and the surface pre-compression stress of glass panels,a modified crack growth model was proposed.Monte Carlo method was used to simulate the randomness of cracks. The finite element method was used to calculate the stress of glass panels.The iterative relationship between the crack length and the crack failure stress was used to analyse the crack failure stress.Through loop calculations,the failure strength and failure time of a large number of glass panels were calculated,then the cumulative probability distributions of failure strength and failure time were achieved The modified failure model can be used to predict the failure time and the failure strength of glass panels under dynamic loading without the limitation of boundary conditions.%基于已有的玻璃破坏模型，首先运用蒙特卡洛法模拟裂纹的随机性，然后应用有限元软件计算玻璃板的应力，并综合考虑裂纹的动态扩展以及不同材料玻璃板的表面预压力，最后根据裂纹长度和裂纹破坏应力之间的迭代关系式，建立了一种修正的单层玻璃板动态裂纹破坏模型。由此改进模型通过循环计算，可计算出大量玻璃试件的破坏应力和破坏时间，从而得到玻璃板破坏应力和破坏时间的累计概率分布。模型验证对比表明，该改进模型可较好地用于动荷载作用下玻璃板的破坏分析预测，且不受玻璃板形状和边界条件的限制。