层压板单搭接胶接结构损伤失效行为表征分析

Characterization and Analysis of the Damage and Failure Behavior of the Single Lap Bond Laminates Structure

为指导层压板胶接结构设计,提高层压板胶接结构的稳定性,基于ABAQUS软件及其用户自定义场变量子程序(USDFLD)和内聚力单元,建立了同时考虑层压板与胶层损伤与失效的层压板单搭接胶接结构的数值分析模型,模型预报结果与试验结果基本吻合.基于该模型对层压板单搭接胶接结构进行应力分析与承载能力影响因素分析,结果表明:胶接结构中胶层剥离应力在胶层内呈对称分布且两端存在应力集中现象,胶层的失效从胶层的两端向中间逐渐扩展;胶层剪应力沿胶层长度方向呈两端高中间低的"凹"形分布;搭接长度是影响胶接接头强度的主要因素,随着搭接长度的增大,胶接接头的强度随之增大并最终趋于稳定值;胶接接头强度和刚度随层压板厚度的增大而增大,但增加幅度较小;层压板铺层形式对胶接结构的承载能力几乎无影响.

In order to guide the design of the bonding laminates structure and improve the stability of the bonding laminatesstructure,the numerical model was created based on the ABAQUS software with its user subroutine and cohesive element.The damage and failure of laminates and adhesive layer in the bonding laminates structure were both considered in themodel.The prediction results agreed well with the experimental results.Moreover,the stress analysis and the impact factor analysis of the bearing capacity of the bonding laminates structure were conducted based on this model.The result of theseanalyses showed that the peeling stress was symmetrical,and the stress concentration existed at both ends in the adhesive layer.The failure extended from both ends to the center in the adhesive layer.The shear stress had a concave shape distribu-tion in the adhesive layer along the length direction.The bonding length is the main factor that affects the strength of the bonding laminates structure.The bonding strength of the bonding laminates structure increases and eventually becomes sta-ble value with the bonding length increasing.The strength and stiffness of the bonding laminates structure increase lowly with the thickness of laminates increasing.The laminates layer has little effect on the bearing capacity of the bonding lami-nates structure.