混凝土Ⅱ型断裂与破坏过程的三维非线性有限元数值模拟

Numereical simulation of mode Ⅱ fracture and failure processes in concrete by 3-dimensional nonlinear FEM

本文基于作者及其合作者近年新提出的两端切口Ⅱ型断裂试件几何和相应的应力强度因子公式的基础上 ,建议一种无切口Ⅱ型断裂试件。然后对不同切口长度的Ⅱ型断裂试件和不同高度和宽度的无切口Ⅱ型断裂试件的断裂破坏过程采用以微面模型 (Micro PlaneModel)为基础的三维非线性有限元分析商用程序进行了数值模拟 ,发现无切口试件在韧带上由剪切应力集中引起剪切裂缝后 ,在韧带区形成纯Ⅱ型断裂和剪切裂缝扩展过程。

Based on the author and his co-workers' recent double-edge notched mode Ⅱ fracture, a relative new non-notched specimen for mode Ⅱ fracture is suggested in this paper. Subsequently, three-dimension nonlinear finite element simulation of this non-notched specimen is used in the numerical simulations based on Micro-Plane-Model. It has been found that when the specimen height exceeds a critical value, the specimen ligament can produce mode Ⅱ shear crack to extend in the absence of mode Ⅰ pattern, which lays basis for further physical experimental investigations for mode Ⅱ fracture.