沉头单钉连接层合板拉伸试验与分析

摘要

An experiment was conducted to study the tensile property of single countersunk composite laminates. A three⁃dimensional progressive damage FE model was established, using ABAQUS/Standard software, based on the Hashin failure criteria. The offset bearing load and ultimate bearing load calculated by the FE model, agreed well with the experimental results, proving the validity of the model. On the basis of this FE model, the process of pro⁃gressive damage to the bolt hole was analyzed, and the influence of bolt tightening torque, bolt⁃hole clearance, and the thickness of the metal plate on the tensile strength of the joint was studied. The results show that:the bolt tight⁃ening torque enhanced the strength of the joint to some extent, and suppressed the emergence of delamination dam⁃age;the bolt hole clearance changed the initial contact condition of the bolt and hole, remarkably reducing the strength of the joint;and the thickness of the metal plate has little effect on the strength of the joint.%为了研究复合材料层合板沉头单钉螺接结构的拉伸性能，对试验件进行了拉伸试验，并通过ABAQUS／Standard基于Hashin失效判据建立了三维渐进损伤有限元模型，计算得到的条件挤压载荷、极限挤压载荷均与试验吻合良好，说明了所建模型的有效性。在此有限元模型的基础上，分析了挤压过程中钉孔的渐进损伤过程，并且研究了螺栓的拧紧力矩、钉孔间隙和连接金属板厚度等因素对结构拉伸强度的影响。结果表明：拧紧力矩在一定范围内可以提高结构强度，并且抑制了分层损伤的出现；钉孔间隙则改变了钉孔初始接触状态，显著地降低结构的强度，而金属板厚度对结构的强度影响较小。