Open-Hole 3D Braided Composites Strength Prediction and Stress Analysis

开孔三维编织复合材料强度预测及应力分析

¹ College of Mechanical Engineering, Donghua University, Shanghai 201620, China
² College of Textiles, Donghua University, Shanghai 201620, China
³ College of Textile and Clothing, Xin Jiang University, Urumchi 830000, China
⁴ Department of Material Engineering, University of British Columbia, Vancouver V6 T1 Z4, Canada

Received: 20 October 2019

Abstract

The stress concentration caused by notches is a common engineering issue for composite structure application. 3D braided composite possess excellent damage tolerance compared to common laminates. The tensile properties of 3D braided composite with open-hole and un-notched were experimentally examined. The mechanic properties of 3D braided composite in other directions are predicted using FGM (Fabric Geometry Model) and finite element analysis. The stress distributions around the hole and perpendicular to the loading direction are analyzed based on Abaqus software. The simulation results were compared with Lekhnitskii's analytical study. The open-hole strength of 3D braided composite was predicted respectively using Average stress failure criteria, Point stress failure criteria (PSC), and also the progressive failure analysis based on different failure criteria. The predicted strength results were compared to the experimental values. The results show the PSC predicted strength matched the experiment, while the progressive failure analysis can predict the failure initiation, propagation and final failure mode.

摘要

由缺陷引起的应力集中是复合材料结构件使用时需要考虑的工程问题。三维编织复合材料相对于传统复合材料具有优异的损伤容限性能。首先对含缺陷前后三维(3D)编织复合材料的拉伸性能进行试验研究，并通过FGM(fabric geometry model)对其他方向材料性能进行预测。然后基于Abaqus有限元对开孔后孔周边应力分布进行分析，并和Lekhnitskii理论进行了对比，同时对沿孔垂直于在载荷方向应力分布进行了观察。分别基于传统平均应力准则和点应力准则以及基于不同失效准则的渐进失效理论对含开孔三维编织复合材料强度进行预测，并与试验结果进行了对比。结果表明，点应力准则可以很好的预测3D编织复合材料含缺陷拉伸强度，而渐进失效分析可以模拟拉伸过程中的损伤起始，损伤扩展和最终破坏模式。