描述混凝土块体间碰撞性能的冲量模型

IMPULSE MODEL OF IMPACT BETWEEN CONCRETE BLOCKS

采用单摆和垂直轨道装置进行了混凝土块体对心碰撞试验。研究参数包括质量比、初始相对碰撞速度、绝对质量和相对加速度。利用LS-DYNA有限元程序数值再现试验过程。在此基础上选取初始碰撞夹角、有效碰撞面积和混凝土抗压强度为研究参数,进行了补充数值试验。基于试验和补充数值试验结果,经回归分析得到了混凝土块体对心碰撞力学模型。此外,考虑到试验中参数的变化,对试验进行了扩展数值模拟。采用模型得到的结果与扩展数值模拟结果吻合良好。

Central impact tests between concrete blocks are performed by a pendulum test system and a drop weight test system. The parameters studied include mass ratio, initial relative impact velocity, Absolute mass and relative accele-ration. The test processes are recurred using LS-DYNA finite element code. Based on the results of numerical simulations, the supplementary numerical tests are carried out and the parameters affecting impact behaviors between concrete blocks, such as initial impact angle, effective impact area and compressive strength of concrete, are studied. The mechanical model of the central impact between concrete blocks is derived from the results of the tests performed in lab and the supplementary numerical tests by means of a regression analysis method. Moreover, considering changes of the test parameters, the extended numerical tests are carried out. It is confirmed that the results from the proposed model agree with those from the extended numerical tests.