套筒节点受压力学性能

Compression performance of threaded-sleeve connection

摘要:

套筒节点是一种新型的装配式空间网格结构节点，其螺纹外伸端为关键受力区域.为了解该节点受压力学性能，首先利用ANSYS对节点进行数值分析模型比选，提出可行的分析模型，研究节点受压性能和应力分布规律；通过试验考察轴心受压、偏心受压作用下节点外伸端受力特征和破坏机理；然后对试件数值模拟结果与试验数据进行对比，验证数值模拟方法的准确性；最后基于数值模拟和试验结果，推导出节点抗压承载力和刚度计算公式.研究表明：套筒节点轴压时承载力约为相同材料等直径、等壁厚圆管的63.2%；当存在较大偏心时，节点偏压承载力约为轴压时的83.9%；轴压试件与偏压试件破坏形式一致，均为螺纹外露段屈曲破坏；数值模拟得到的节点抗压性能与试验结果吻合较好，节点分析模型合理；理论分析得到的节点承载力和刚度计算公式与试验结果吻合较好.套筒节点受力合理可靠，其薄弱部位为螺纹外露段，受压时呈屈曲破坏.

Abstract:

The threaded-sleeve connection (TSC) is a new type of connection for grid structure, of which the key part situates at the threaded extended end. The simulation models of TSC were established and compared by ANSYS. The compression mechanical property and stress distribution were analyzed firstly. The performance of compression and eccentric compression were tested through experiments. The simulation results were compared with test data to verify the correctness of the FE model. Based on the simulation and experimental results, the theoretical formulas of compression capacity and stiffness of the extended end were developed. It is illustrated that the capacity of TSC under compression is about 63.2% of that of the pipe with same material, diameter and wall thickness. When subjected to large eccentricity, the capacity of TSC decreases to about 83.9% of the axial compressive capacity. The failure form of the specimens under compression or eccentric compression is the buckling of the extended threads. The simulation results agree well with the test results, which illustrates the effectiveness of the FE method, and the theoretical results are also in good agreement with the test data. The TSC shares good compression performance, and the most weakness area exists in the extended part of the threads, the buckling of which will lead to the failure of the connection.