离散元模拟钢筋混凝土靶板贯穿响应研究

Study on Perforation Responses of Reinforced Concrete Slab by Discrete Modeling

提出了圆截面梁单元高斯积分点分布方案以及一种钢筋-基体接触作用模型,基于LDPM离散单元建立了钢筋混凝土侵彻数值计算模型。模拟刚性弹贯穿48 MPa和140 MPa压缩强度的钢筋混凝土靶板,通过对比弹体剩余速度和靶板破坏形态,验证了模型对于钢筋混凝土贯穿问题的适用性。仿真结果表明,140 MPa强度混凝土靶板内钢筋对于弹体作用更强,对于出靶剩余速度影响更大。对比不同弹着点和钢筋尺寸的贯穿仿真,弹着点在一根钢筋位置和两根钢筋交叉处,出靶速度分别降低了约12 m/s和45 m/s;弹着点位置在钢筋交叉处时,通过增大钢筋尺寸提高配筋率能够明显降低贯穿剩余速度。

A new distribution scheme of Gauss integration point and a new rebar-matrix interaction model were presented. A numerical model for rebar concrete （RC）plate perforation was established based on lattice discrete particle model（LDPM）. The compressive strength of 48 MPa and 140 MPa of RC plates perforation was simulated respectively. The proposed model was validated for the perforation simulation in terms of residual velocity and damage mode. Under the conditions of 140 MPa compressive strength, the rebar of reinforced concrete has greater resistance on the impact projectile compared to the conditions of 48 MPa compressive strength. Numerical results indicate that the residual velocity decreases by 12 m/s and 45 m/s while projectile impacting one rebar or two rebar joints. It can significantly decrease the projectile residual-velocity to increase the rebar diameter while the impact position is at the junction of two rebars.