输电杆塔中刚性法兰螺栓的附加拉力

Additional Tension of Rigid Flange Bolt for Transmission Tower

刚性法兰中的法兰盘在受拉时会发生轻微变形,在螺杆中产生附加拉力,现有计算方法没有单独考虑附加拉力的影响。螺杆内力在试验中不易准确测得,因此建立6个不同直径、螺栓个数的包含各部件的刚性法兰模型(钢管分别为φ219×8、φ506×8),根据节点实际受力情况分别设置接触行为和参数。计算结果表明,螺栓变形主要集中在螺杆部分;螺杆上的附加拉力约占钢管总轴力的6%;把螺杆的弯矩计入后,截面最大应力平均比其强度设计值高10%,现有计算方法偏不保守。考虑刚性法兰工程实际,给出了适用的螺栓承载力计算公式,为设计提供参考。

Some slight deformation occurs when tension is applied in rigid fange joint, and additional tensile stress is produced in bolt stem. Existing design method ignores the efect of such tensile stress. A series of fnite element models of rigid fange joints are established which contain full components such as pipes（φ219×8,φ506×8）, fanges, bolts, etc. The actual contact behavior and parameters are applied for contact pairs in these FE models. The results shows： the deformation occurs mainly in bolt stem; the proportion of additional tensile force is 6% of total; in consideration of moment in bolt stem, the maximum stress in section is 10% higher than design value. A compatible design formula is provided for bolt calculation, and that can be references for engineering design.