混凝土重力坝抗爆性能及抗爆措施研究

Study on the antiknock performance and measures of concrete gravity dam

大坝受袭的可能方式主要有直接命中坝体爆炸、库前水中爆炸、库区近空爆炸。本文考虑爆炸冲击荷载作用下混凝土的高应变率效应,通过构建重力坝侵彻爆炸、水中爆炸和空中爆炸的全耦合模型,对不同爆炸方式下的大坝动态响应进行了全性能数值仿真,探讨了混凝土重力坝在不同爆炸方式下的可能破坏模式及抗爆性能,并重点研究了水中爆炸冲击荷载下局部配置抗爆钢筋对大坝动态响应的影响,给出了配筋前后大坝开裂破坏范围及坝顶动位移响应,为大坝抗爆性能评估和防护设计提供基础。研究表明,水中爆炸冲击荷载作用下大坝的破坏效应较大,水下贴坝面爆炸时大坝破坏最严重;侵彻爆炸和空中爆炸的毁伤效应主要表现为坝体的局部破坏效应;采取配筋抗爆措施能够显著限制坝体裂缝的扩展与贯穿,减少坝体开裂破坏范围,有效地改善坝体的抗爆性能。

Dams may be mainly subjected to penetration explosion,underwater explosion,air explosion.Strain rate effect of concrete was taken into consideration in the establishment of fully coupled model of gravity dams.Numerical simulation was conducted to study the dynamic response of the dam when subjected to different blast loads.The possible failure mode and antiknock performance of concrete gravity dams was discussed.According to the dynamic response and failure mode of dam subjected to underwater explosion,the impact of local blast-resistant reinforcement was researched.At the same time,the extent of cracks and the dynamic displacement response of dam crest were also given.This can provide references to the antiknock performance-based assessment and protective design.Our research shows that damage effects of the dams are larger when subjected to underwater blast loading,and the dam is in the most severely damage when the bomb is attached to dam surface.Penetration explosion and air explosion effects of damage on the dam are characterized by local damage effects.Reinforcement measures can limit antiknock expansion of cracks significantly,reduce the extent of damage,and improve the antiknock performance effectively.