多点同时爆炸对钢筋混凝土方柱构件的毁伤特性  

Damage characteristics of reinforced concrete square column components under multi-point simultaneous initiating

作　　者：武伟超[1] 夏柳 潘艾刚 王亚飞[1] 王强[1] WU Weichao;XIA Liu;PAN Aigang;WANG Yafei;WANG Qiang(State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]北京理工大学爆炸科学与技术国家重点实验室,北京100081

出　　处：《爆炸与冲击》2023年第12期94-107,共14页Explosion and Shock Waves

摘　　要：为了研究炸药多点协同爆炸对钢筋混凝土方柱构件的毁伤特性、动力响应和破坏机理的影响,设计了柱身单节点、邻面双节点、邻面四节点和全包围四节点4种爆炸试验工况,对4根钢筋混凝土方柱开展爆炸试验。基于试验结果,利用显式动力分析软件LS-DYNA建立了精细化有限元模型,系统分析了炸药中心截面毁伤特性和应力发展时程。研究结果表明:相同爆炸总当量下,炸药节点数量和布置位置对方柱毁伤效果有显著影响;多点爆炸下方柱毁伤效果均大于单点爆炸工况且钢筋混凝土方柱均产生贯穿破坏,邻侧四节点爆炸钢筋混凝土方柱混凝土破坏程度及加速度响应最大;对比邻侧多点爆炸工况发现,炸药节点数量的增加可以有效提高爆炸对方柱的毁伤效应;全包围四节点爆炸工况方柱最早进入全截面高应力状态,并出现4处角部混凝土应力集中,而邻面多点爆炸工况进入全截面高应力状态较晚,仅有3处截面角部混凝土应力集中;单点爆炸时混凝土内部测点应力随到爆心距离增大而减小,而多点爆炸工况下多个爆炸应力波在方柱截面内部耦合叠加,中心混凝土处应力显著增大;受到应力波空间耦合叠加的影响,邻面四节点爆炸工况下方柱截面中心混凝土峰值应力达37.3 MPa,相较其他3个爆炸工况应力增幅达到3.82倍、1.21倍和0.67倍,应力耦合力度增大是导致该工况方柱毁伤最严重的直接原因。To investigate the influence of damage characteristics,dynamic response,and failure mechanism on reinforced concrete(RC)square columns under multi-point simultaneous initiation,a series of experiments were conducted on RC square columns subjected to synchronous contact explosive loading using single,double,and four-point charges.Furthermore,LS-DYNA was used to analyze the damage characteristics and stress evolution process based on the experimental results obtained from the explosive loading.The analysis results indicate that the damage effect of RC square columns relies on both the number of detonation points and the placement position,given the same total mass of explosives.Multi-point simultaneous initiation causes superior damage to RC square columns with both crushed and punched damage,as compared to single-point explosions.Additionally,the degree of damage and acceleration response of the RC square columns is the highest at the condition of four-point charges on adjacent sides.The effectiveness of enhancing the damaging effect on RC square columns is directly correlated with the increase in the number of detonation points.The RC square column initially enters a high-stress state throughout the entire section,and in the condition of four-point charges placed on all four sides,there are four corners where the concrete stress is concentrated,leading to enhanced damage effects.During single-point initiation,the stress inside the concrete at the measuring point decreases as the distance from the center of the explosion increases.However,during multi-point initiation,when multiple explosion stress waves are combined within the cross-section of the RC square column,the stress at the central concrete significantly increases.Taking into account the spatial coupling and superposition of stress waves,the concrete's peak stress at the center of the RC square column section increased significantly under the explosive conditions of four-point charges on adjacent sides.Specifically,the peak stress reached 37.3 MPa,with st

关 键 词：多点接触爆炸荷载 钢筋混凝土方柱 毁伤特性 精细化有限元模型 

分 类 号：O383[理学—流体力学]