不同强度混凝土及钢筋对钢筋混凝土柱抗爆性能的影响

Effects of High Performance Concrete and High Strength Steel on the Blast Response of Steel Reinforced Concrete Columns

以钢筋混凝土(RC)柱在爆炸载荷作用下的毁伤和防护为背景,研究新型材料超高性能混凝土(UHPC)、高强混凝土(HSC)和高强钢筋(HSS)对RC柱在近距离爆炸载荷作用下的动态响应。利用有限元显式动力分析软件LS-DYNA建立RC柱三维有限元模型,该模型运用光滑粒子流体动力学方法考虑了压缩碎裂和震塌局部效应。通过实验验证数值仿真算法、材料模型和参数的正确性,详细研究了UHPC、HSC和HSS对RC柱抗爆性能的影响。结果表明:相同比例距离0.8 m/kg1/3下,与低强度混凝土柱(抗压强度30 MPa)和HSC柱(抗压强度80 MPa)相比,抗压强度140 MPa UHPC柱承受的最大梯恩梯药量提高10倍;HSS与UHPC组合增加了柱的脆性,RC柱更易发生剪切破坏。

A numerical model of the reinforced concrete(RC)columns was developed using software LS-DYNA.In the numerical model,the smooth particle hydrodynamics(SPH)method is used,and the spalling effect and strain rate effect are considered.The finite element model is valiated through the experimental data.A parametric study is further carried out to examine the effects of ultra-high performance concrete(UHPC),high strength concrete(HSC)and high strength steel(HSS)on the blast resistance of RC columns.The results show that,compared with normal strength concrete column(30 MPa compressive resistance)and high strength concrete column(80 MPa compressive resistance),the blast resistance of UHPC column(140 MPa compressive resistance)is increased by ten times under same scaled distance of 0.8 m/kg1/3.However,HSS results in more brittle damage in UHPC columns.The damage mode of RC columns changes from flexure to shear.