摘要
混凝土重力坝受水下爆炸作用时的响应涉及到几何、材料和边界条件的非线性,很难得到解析解,这类高度非线性问题更多依赖于数值模拟。数值模拟中,将有限元法与无网格法结合起来。使用有限元网格计算结构未破坏阶段的动态响应,在结构有限元网格达到破坏的瞬间将其转变为无网格粒子继续计算,既避免了由于有限元单元删除导致的结构质量不守恒问题,又能准确地添加模型的边界条件。基于离心机缩比试验结果验证数值模型的准确性,进行重力坝损伤演化的研究,明确了冲击波与爆轰产物分别对坝体造成破坏。通过数值模拟,发现近场水下爆炸的冲击波首先会对坝体造成局部破坏,主要表现为成坑破坏与坝头部位的混凝土大块破碎。爆轰产物主要会造成坝体的整体破坏,使得坝体内部、中部、底部形成损伤带。
The concrete gravity dam’s response to the effect of underwater explosion involves the nonlinearity of geometry, material and boundary conditions, and it is difficult to obtain analytical solutions. Such highly nonlinear problems rely more on numerical simulation, in which the finite element method(FEM) can be combined with the meshless method. Using the finite element mesh to calculate the dynamic response of the structure in the undamaged stage, and converting it into meshless particles to continue the calculation when the finite element mesh of the structure reaches the destruction, can not only avoid non-conservation of the structural mass caused by deletion of finite elements, but also accurately add the boundary conditions of the model. Based on the centrifuge scaled test results, the accuracy of the numerical model was verified, the damage evolution of the gravity dam was studied, and the damage of the dam body caused by the shock wave and detonation products was identified. It is found during the numerical simulation that the shock wave of the near-field underwater explosion will first cause local damage to the dam body, characterized mainly by cratering damage and large concrete breakage at the dam head. The detonation products mainly cause an overall damage to the dam body, forming damage zones in the interior, middle and bottom of the dam body.
作者
马上
王振清
陈叶青
李述涛
MA Shang;WANG Zhenqing;CHEN Yeqing;LI Shutao(Harbin Engineering University,Harbin 150001,China;Institute of Defense Engineering,AMS,PLA,Beijing 100850,China)
出处
《防护工程》
2022年第2期22-29,共8页
Protective Engineering
关键词
水下爆炸
混凝土重力坝
冲击波
underwater explosion
concrete gravity dam
shock wave
