一种考虑纤维桥接影响的三线性内聚力模型

A trilinear cohesive model considering the effect of fiber bridging

为了实现碳纤维层合板DCB试件Ⅰ型分层扩展仿真分析,学术界常采用内聚力模型建立分层扩展模型。但是目前各大商业软件上嵌入的双线性内聚力模型只能实现无纤维桥接或少量纤维桥接下的碳纤维DCB试件Ⅰ型分层扩展。现有研究发现,纤维桥接是碳纤维DCB试件分层扩展中不可忽视的现象。为此本文从双线性内聚力模型出发,开发了一种能够描述大范围纤维桥接的三线性内聚力模型。该模型基于两个双线性内聚力模型构建,两个双线性模型分别用于描述分层起始和纤维桥接。通过与实验结果和双线性内聚力模型数值仿真结果比较,验证了该模型的有效性和优越性。

In order to realize the simulation analysis of typeI layered expansion of carbon fiber laminate DCB specimens,the academia often uses the cohesive force model to establish a layered expansion model.However,the bilinear cohesive model embedded in the major commercial software can only realize the type I layered expansion of carbon fiber DCB specimens without fiber bridging or with a small amount of fiber bridging.Existing studies have found that fiber bridging is a phenomenon that cannot be ignored in the delamination expansion of carbon fiber DCB specimens.Therefore,this paper develops a trilinear cohesion model that can describe the large-scale fiber bridging based on the bilinear cohesive model.The model is constructed based on two bilinear cohesion models,which are used to describe delamination initiation and fiber bridging,respectively.The validity and superiority of the model are verified by comparing with the experimental results and the numerical simulation results of the bilinear cohesion model.