内聚力界面单元与复合材料的界面损伤.pdf

力学学报990314 力学学报 ACTA MECHANICA SINICA 1999年　第3期　No.3　1999 内聚力界面单元与复合材料的 界面损伤分析 1) 周储伟 杨 卫 方岱宁 摘要　推导了一种基于内聚力模型无厚的界面单元,用来模拟复合材料纤维与基体之间 的界面层.研究了纤维周期分布的复合材料受横向荷载时,在界面不同的强韧性条件下其 界面损伤演化的规律和对复合材料整体性质的影响. 关键词　复合材料力学,界面单元,内聚力模型,损伤 COHESIVE INTERFACE ELEMENT AND INTERFACIAL DAMAGE ANALYSIS OF COMPOSITES1) Zhou Chuwei Yang Wei Fang Daining (Department of Engineering Mechanics, Tsinghua University, Beijing100084, China) Abstract An interface elementbased on the cohesive zone model is employed to simulate thefiber/matrix interface in composite. The cohesive zone model used hereis viewed as a phenomenological model. A potential function is adoptedto describe the relationship between the interface traction and theinterface displacement jump. Two sets of interface parameters areadopted to represent the interface strength and toughness respectively.This model can simulate the evolution of interface damages, which arecoupled in the normal and tangential directions. The interface element has nothickness initially. 　　This interface damage model is performed to composites which haveperiodic array of fibers and are subjected to a transverse load. Forsymmetry, the computational representative element (RVE) contains aquarter of fiber. The fiber is assumed as elastic material and itsstiffness is much higher than that of the matrix material. The matrix isassumed as isotropic hardening elastic-plastic material. Finitedeformation is considered. The interface damage evolution and itseffect on the properties of composites under the conditions of variousinterface strengths and toughness is investigated. The results show thatthe debonding starts at the polar region of the fiber and moves to theequator region with the loading increas