摘要
用梁-颗粒模型BPM^2D对卵形头和平头动能弹贯穿混凝土平靶的过程进行数值模拟，给出贯穿过程中混凝土内部速度场的变化情况及混凝土的破坏区域。梁-颗粒模型BPM^2D是在离散元法基础上，结合有限元法开发的二维数值计算模型。在模型中用3种类型粱单元形成混凝土数值试样，每种类型梁单元的力学性质均按Weibull分布随机赋值以模拟混凝土细观结构的非均匀性，同时梁单元的强度随应变率不同而变化。基于计算结果，分析了弹头部形状对贯穿过程的影响。卵形头弹的贯穿过程是一种刺穿性模式，而平头弹是挤凿性模式。贯穿同样的靶板，平头弹的能耗高于卵形头弹，残余速度小。通过将卵形头弹的计算结果与试验数据相比较，表明梁-颗粒模型可有效应用于计算和模拟脆性材料动态破坏问题。
The perforation into a plain concrete panel with ogival and flat nose perforators is numerically simulated with the BPM^2D （beam-particle model in two dimensions）. The varieties of velocity field in concrete and failure zone surrounding the hole are described. The BPM^2D is presented on the basis of the DEM and the FEM. Three types of beam in the BPM^2D have been used to form numerical model of concrete. The mechanical properties of every type beam vary with their strain-rate, and are randomly allocated according to Weibull distribution to reflect the initial heterogeneity of concrete at the mesoscale level. The effects of perforators nose shapes on the perforation are discussed with the calculated results. The destruction mode for the ogival nose perforator is a stabbing one, while that for the flat nose perforator is a plugging one. The consumed energy for perforating a uniform target with the fiat nose perforator is greater than that with the ogival nose perforator, so that the residual velocity of the former is lower. The comparison of the simulated results with the experimental data shows that the BPM^2D is applicable to the simulation of dynamic failure problems for brittle materials.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2005年第A01期4843-4848,共6页
Chinese Journal of Rock Mechanics and Engineering
基金
东北大学博士学位论文资助项目（200211）
关键词
数值模拟
混凝土
贯穿
弹头部形状
梁-颗粒模型
numerical sirnulation
concrete
perforation
nose shape of perforators
beam-particle model
