垂直度误差影响复合材料层合板层间应力分析
Effect of Hole Perpendicularity Error on Inter-laminar Stress of CFRP

采用有限元仿真的方法分析了连接孔垂直度误差对连接区层间应力的影响规律，基于层间失效准则对垂直度误差影响接力学性能进行了预测并试验验证。结果表明：垂直度误差影响螺栓与连接件之间的接触关系，造成连接区应力分布不均匀；螺栓在带有垂直度误差的连接孔中预紧时会发生位姿调整，其中以螺栓杆挤压孔壁为主；层间剪应力随垂直度误差的增加而增大，是造成分层失效的主要原因；适当提高螺栓预紧力有利于缓解垂直度误差带来的不良影响。
The effects of the hole-perpendicularity error on the inter-laminar stress and the mechanical performance of the joint are investigated. It is found that the stress distribution around the hole is heavily affected by the mentioned error. The bolt's posture may adjust when it is fastened in a bolt hole with perpendicularity error, during which the bolt shank bearing the hole wall plays an important role. Moreover, the inter-laminar shear stress increases with the increasing of hole perpendicularity error, which is the main reason for inducing delamination failure. Finally, to increase the fastening torque can help to reduce the negative effects caused by hole perpendicularity error, which was proved by the experimental results