氯盐侵蚀后螺栓球节点抗拉承载力试验研究与数值模拟

Experimental Study and Numerical Simulation on the Tensile Bearing Capacity of Bolt-Sphere Joints After Chloride Corrosion

螺栓球节点因具有受力明确、安装施工简易等优点,被广泛应用到空间网格结构中,起到连接杆件以及传递荷载的作用,但腐蚀是影响网格结构使用寿命的重要原因之一。利用周期喷雾循环模拟试验来研究氯盐侵蚀对螺栓球节点的抗拉承载性能、破坏模式以及锈蚀质量损失率的影响。得出:螺栓球节点试件的抗拉承载力随腐蚀时间的增加而逐渐降低。此外,随着腐蚀时间的增加,试件的锈蚀质量损失率逐渐增大,而且只要腐蚀时间相同,具有拧入缺陷试件的锈蚀质量损失率与无拧入缺陷试件的相差不大。最后,通过有限元分析建立了适用于模拟螺栓球节点抗拉承载性能的模型,有限元模拟结果与试验研究结果吻合良好。

Bolt-sphere joints have been widely used in space grid structures to connect members and trans-fer loads,because of the advantages of clear force and simple installation.However,corrosion is one of the important factors that affect the service life of grid structures.Cyclic spray simulation test was used to study the influence of chloride corrosion on the tensile bearing capacity,failure mode and corrosion mass loss rate of bolt-sphere joints.It was concluded that the tensile bearing capacity of bolt-sphere joints decreased grad-ually with the increase of corrosion time.In addition,the corrosion mass loss rate of specimens gradually increased with the increase of corrosion time,and as long as the corrosion time was the same,the corrosion mass loss rate of specimen with screw-in defects was not significantly different from that of specimen without screw-in defects.Finally,a model suitable for simulating the tensile bearing capacity of bolt-sphere joints was established by finite element analysis,and the simulated results were in good agreement with the exper-imental results.