摘要
动力多灾害作用下工程结构防护问题已成为当前研究的热点,采用LS-DYNA软件对ISO-834标准火灾后的钢管RPC柱抗爆动态响应全过程进行了模拟。首先采用ANSYS软件模拟钢管RPC在高温作用下的温度场分布,进一步得出钢管和核心混凝土的残余强度,在此基础上分别用弹塑性模型和K&C模型描述钢管和RPC的本构关系。结合试验研究,采用参数化分析方法研究了荷载参数(受火时间、比例距离、轴向荷载)、几何特征参数(含钢率、长径比)和材料性能参数(钢材强度)对火灾后钢管RPC柱抗爆性能的影响规律。结果表明:数值模拟结果和试验结果吻合良好,说明本文模拟方法可以合理刻画火灾后钢管RPC柱抗爆动力行为。受火后的钢管RPC柱在爆炸荷载作用下钢管仍能有效约束核心RPC,柱的破坏形态以弯曲破坏为主,表现出良好的抗爆性能。高温作用导致钢管混凝土强度裂化,刚度降低,爆炸作用下构件变形明显增大;减小比例距离引起构件中部出现更明显的变形,且支座处有剪切破坏趋势。
Engineering structure protection problems under dynamic multi-disaster become a hot topic of current research. Here, the full process of anti-blast dynamic response of a fire(ISO834)-damaged reactive powder concrete(RPC)-filled steel tubular column subjected to blast loading was simulated with the software LS-DYNA. Firstly, the FE software ANSYS was used to simulate RPC-filled steel tube’s temperature field distribution under high temperature. Then residual strengths of steel tube and core concrete were obtained, respectively. The elastic-plastic model and K&C one were used to describe constitutive relations of the steel tube and core concrete, respectively. Combining with test study, the parameterized analysis method was used to investigate effect laws of load parameters including fire time, proportional distance, and axial load, geometric feature parameters including steel ratio, ratio of length to diameter and material strength on anti-blast performance of fire-damaged RPC-filled steel tube column. The results showed that the numerical simulation results agree well with the test ones, so the proposed simulation method can reasonably describe anti-blast dynamic behavior of fire-damaged RPC-filled steel tube column;core RPC can be constrained effectively by fire-damaged steel tube column under blast load, failure modes of RPC-filled steel tube column are mainly bending type to reveal good blast-resistance performance;high temperature causes steel concrete’s strength cracking, stiffness dropping, and component deformation significantly increasing;decrease in proportional distance can cause more obvious deformation at the middle of steel tube column, and there is a shear failure trend at its supports.
作者
邹慧辉
陈万祥
郭志昆
周子欣
ZOU Huihui;CHEN Wanxiang;GUO Zhikun;ZHOU Zhixin(State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact,Army Engineering University of PLA,Nanjing 210007,China;School of Civil Engineering,Sun Yat-Sen University,Guangzhou 510275,China)
出处
《振动与冲击》
EI
CSCD
北大核心
2019年第21期155-163,171,共10页
Journal of Vibration and Shock
基金
国家自然科学基金(51378498
51578541)
江苏省自然科学基金项目(BK20141066)
关键词
爆炸荷载
火灾
钢管RPC
动力响应
数值模拟
blast load
fire attack
reactive powder concrete(RPC)-filled steel tube
dynamic response
numerical simulation
