基于P-I模型的爆炸载荷下波纹板防爆墙抗爆能力评估

摘要

In view of the insufficient ability to assess the damage of corrugated blast walls subjected to blast loads by using the SDOF model,a NLFEA (nonlinear finite element analysis model was built to analyze the dynamic response and damage mechanism of three kinds of typical corrugated blast walls on a platform.P-I diagrams and a simplified empirical equation were both derived with the P-I model where the material rupture was defined as a critical indicator and the maximum rupture strain criterion was combinedly used.Using the simplified empirical equation,a study on the critical parameters of the equation,i.e.the critical values of the overpressure and the impact,was performed under different sizes of the sectional profiles of corrugated blast walls with the variance analysis method.Based on the least squares method,a general empirical equation under different sizes of the sectional profiles was derived,with which the prediction of the blast loading resistance of a new corrugated blast wall was made.In comparison with the SDOF model,the results by the general empirical equation have better correlation with those by the simulations.It is concluded the empirical equation is of convenience and accuracy to assess the damage of corrugated blast walls and can provide a guidance to the initial design and consequence assessment of corrugated blast walls.%以非线性有限元分析方法为基础,分析三种波纹板防爆墙在不同爆炸载荷下的动态响应及破坏机理,基于最大破裂应变准则,采用P-I模型,拟合三种类型波纹板防爆墙的抗爆评估P-I曲线,获取确定拟合不同防爆墙P-I曲线的统一经验方程形式,借助方差分析,进行波纹板防爆墙P-I曲线的参数影响性分析,基于最小二乘法,建立任意截面尺寸波纹板防爆墙P-I曲线的预测经验公式,结合实际案例,预测某截面尺寸下波纹板防爆墙的抗爆能力,并与实验实测值、单自由度理论模型进行对比.预测经验公式由于考虑应变率效应及局部响应效应,更具有准确性,其可用于快速、便捷地进行油气爆炸载荷下任意截面尺寸防爆墙抗爆能力评估,为工程人员初始抗爆设计、灾后后果评估提供参考.