近场爆炸时混凝土桥墩的动力响应分析  

Study of Concrete Piers Dynamic Response under Close Blast Loading

作　　者：吴亮[1] 胡志坚[1] 孙立志[1] 张一峰[1] 

机构地区：[1]武汉理工大学交通学院,武汉430063

出　　处：《爆破》2015年第3期105-113,共9页Blasting

基　　金：江西省科技计划项目(20132BBG70107);中央高校基本科研业务费专项资金项目(2013-IV-016)

摘　　要：为研究爆炸荷载作用时混凝土桥墩的动力响应,基于爆炸基本理论,开展近爆作用下混凝土桥墩的数值模拟与破坏模式研究,并通过方柱墩与圆柱墩对比、墩柱配筋方式与爆心位置变化等分析墩柱底部的水平位移和水平速度时程变化,进而研究墩柱的抗爆性能与破坏形态。研究结果表明:同等条件下圆形墩柱的抗爆能力要优于方形墩柱;爆炸荷载作用下墩柱纵向主筋的配置可改变墩柱的破坏形态,且墩柱底部的抗剪能力主要靠纵向主筋提供,箍筋的抗爆作用有限;近场爆炸时地基对墩柱底部的约束作用明显,进行墩柱抗爆设计时,可以结合基于性能的抗震理论实现墩柱底部的塑性铰设计。In order to study the dynamic response of concrete piers under blast loading, the numerical simulation and failure mode study for concrete piers under close blast loading were performed. To analyze blast resistance of concrete piers, the parameters including horizontal velocity and displacement of pier bottom were investigated with re- spect to comparison of circular and square piers, reinforcement arrangements and location of detonation. The results show that circular piers provided better blast resistance than square piers under the same blast circumstance. Failure modes for concrete piers were determined by lon^tudinal rebar arrangement, which contributed to the major part of shear capacity of pier bottom when subjected to close blast loading. The stirrup effect on blast resistance of concrete piers was limited. In addition, the restraint effect of basement was significant to the pier bottom under close blast loading,and performance from seismic design concept could be applied in plastic hinge design at the bottom of con- crete piers for anti-blast.

关 键 词：混凝土桥墩 近场爆炸荷载 动力响应 地基约束作用 塑性铰 

分 类 号：U443.22[建筑科学—桥梁与隧道工程]