聚氯乙烯树脂层对球罐爆炸碎片连锁破坏概率的影响

依据塑性理论分析聚氯乙烯树脂保护层存在条件下的碎片抛射与破坏目标的过程,提出碎片穿透保护层的厚度与动能消耗的计算模型,并根据碎片抛射方程确定碎片碰撞及引发目标连锁破坏的概率。以球罐为例,应用Monte-Carlo法模拟了保护层对爆炸碎片连锁破坏效应的影响规律。结果表明:保护层可占有较大的破坏概率,显著减少目标破坏的可能性,目标连锁破坏概率由于目标穿透破坏概率的下降而平均降低了约4个数量级。偏差分析显示,保护层对连锁破坏概率的降低程度超过了99%。碎片连锁破坏概率随保护层厚度的变化呈现指数递减关系。研究结果可为球罐防护措施的合理选材与设计提供理论依据,为降低多米诺效应出现的频率,应最大限度地避免罐体本身与碎片的接触。

Influence of protective layer of polyvinylchloride resin on domino effect risk caused by fragments from spherical vessel explosion

The fragment flight and the damage target were investigated under conditions of the protective layer of polyvinylchloride(PVC) resin based on the plasticity concepts.The models for calculating the penetration depth to the protective layer and the dissipated kinetic energy of the fragment were proposed,and the domino effect risk after impact was confirmed by the movement equations of the fragment.A spherical vessel with fragment projection was taken as an example to explore the influence of the protective layer on the domino effect risk by Monte-Carlo simulations.The results showed that the protective layer occupied the larger probability of rupture and cut down the failure possibility of target;the domino effect risk was lowered by an average of about 4 orders of magnitude due to the reduction of the failure probability of the impacted target.The relative deviations demonstrated that the protective layer reducted more than 99% on the domino effect risk.The risk occurrence of the domino effect decreased exponentially according to the thickness of the protective layer.The results provided theoretical basis for the reasonable choice of materials and design of the protective measures of spherical tank.The interaction between the tank and the fragment should be avoided to stop the domino effect.