螺栓连接层合板孔边挤压应力三维分布

孔边应力是复合材料连接设计中强度校核的重要依据，装配间隙对其有明显的影响。针对准各向同性铺层层合板单搭接连接结构，首先采用弹性基剪切梁模型推导了螺杆挠度的解析解，给出挤压载荷沿着层合板厚度方向的分布。在此基础上，将能计及装配间隙的二维情况下孔边挤压应力分布的Persson模型推广到三维情况，得到了孔边挤压应力分布及应力集中系数。理论结果通过三维细节有限元方法进行了验证。最后采用理论方法分析了装配间隙、层合板厚度及钉载对应力集中系数的影响。

Three-dimensional bearing stress distribution at bolt-hole in quasi-isotropic laminates

Hole edge stress is an important basis for strength check in composite joints design, and bolt-hole clearance has obvious influence on it. For the single-lap joint structure of quasi isotropic laminated plates, the elastic foundation shear beam model was adopted and the analytical solution of the shank deflection was derived. The distribution of the bearing load along the thickness direction of the laminates was given. On this basis, the Persson model of the bearing stress distribution at the hole edge was extended to the three-dimensional case, the stress distribution and the stress concentration factor at the hole edge were obtained. The theoretical results were verified by the three-dimensional detailed finite element method. Finally, the influence of the clearance, laminates thickness and external load on stress concentration factor was analyzed by theoretical method.