EPS泡沫在径向不耦合爆破中吸能效应数值仿真

Numerical Simulation on Energy-absorption of EPS Geofoam in Radical Uncoupled Blast

摘要:

不耦合装药在工程爆破实践中有着广泛的应用，而采用EPS泡沫作为不耦合间隙充填物的情形迄今研究较少。本文基于大型非线性显式动力分析有限元程序LS-DYNA，对初始密度分别为12.0、21.0、27.0 kg•m-3的EPS泡沫作充填材料的径向不耦合爆破进行数值模拟。分析了在嵌入不同密度EPS泡沫下混凝土爆破中的损伤分布以及炮孔周围压力、速度和加速度衰减规律，并与水不耦合以及空气不耦合爆破工况的模拟结果进行了对比。结果发现：EPS泡沫可有效地吸收爆炸波能量，减小周围混凝土的损伤区范围。而且，EPS泡沫初始密度ρ0对混凝土损伤影响较大，即随着ρ0的增大，EPS泡沫吸能减振功效变得相对不明显；一定程度上，增到EPS泡沫ρ0与降低不耦合系数Kd可取得相近的爆破效果。此外，在EPS泡沫不耦合爆破中，Kd控制2.0以内既可取得较好爆破效果，又能降低成本。

Abstract:

Uncoupled blast has wide applications in engineering practice. However, the blast using EPS foam as filling material is rarely investigated so far. Based on the large-scale finite element code, LS-DYNA, with explicit integration, the numerical simulations on radical uncoupled blast with filled EPS foam of three initial densities (12.0、21.0、27.0 kg•m-3 ) are performed. The distribution of concrete damage and the evolution laws of peak hydrostatic pressure, velocity and acceleration of particles around the blasthole are analyzed. The comparisons between the radical foam uncoupled blast with the radical air and water uncoupled cases are also made. Results show that EPS foam can effectively absorb blast energy, reduce the damaged zone around the blasthole. The initial density of EPS foam ρ0 exerts a significant impact on the concrete’s damage distribution. With the increase of ρ0, EPS foam has less capacity of energy absorption and vibration attenuation. Furthermore, increasing the initial density of EPS foam and reducing the decoupling coefficient may achieve similar blast result to a certain extent. Besides, Kd should be confined to 2.0 in EPS foam decoupled case for better effects and lower blast cost.