钢管再生混凝土柱侧向冲击作用的机理分析及惯性力研究

Study on lateral impact mechanism and inertia force of steel tubular recycled concrete column

运用ABAQUS/Explicit有限元软件对圆钢管再生混凝土柱侧向冲击作用进行数值模拟。通过与落锤冲击试验结果对比验证有限元模型的合理性。研究冲击过程中钢管再生混凝土柱受力机理及惯性力分布,分析不同冲击速度、冲击质量、边界条件和截面含钢率对柱惯性力分布的影响。结果表明:所建立的有限元模型能很好地吻合落锤冲击试验结果;冲击过程中柱固支端钢管先出现损伤,随后跨中受拉侧钢管损伤,固支端核心再生混凝土受拉侧先开裂,随后是跨中冲击附近再生混凝土开裂;冲击质量、边界条件对柱惯性力分布影响较小,冲击速度是影响惯性力分布的关键因素,冲击速度由5m/s增加至20m/s,冲击力峰值时惯性力由486.24kN增加至1266.06kN,增加160%,惯性力沿柱分布图呈“弓箭”形状。

ABAQUS/Explicit finite element software is used to simulate the lateral impact of circular steel tubular recycled concrete column. The rationality of the finite element model is verified by comparing with the results of the drop weight impact test. The stress mechanism and inertia force distribution of the steel tubular recycled concrete column during the impact process are analyzed. The effects of different impact velocities, impact masses, boundary conditions and section steel content on the distribution of inertia forces are analyzed. The results show that the established finite element model is in good agreement with the experimental results of drop hammer impact. In the process of impact, the steel tube at the fixed support end of the column is damaged firstly, and then the steel tube at the tensile side of the mid-span is damaged. The core recycled concrete at the fixed support end firstly is cracked at the tensile side, and then the recycled concrete near the mid-span impact is cracked. The impact mass and boundary conditions have little influence on the distribution of inertia force, and the impact velocity is the key factor affecting the distribution of inertia force. When the impact velocity increases from 5 m/s to 20 m/s, the peak impact force increases from 486.24 kN to 1266.06 kN, increasing by 160%. The distribution diagram of inertia force along the column shows a "bow" shape.