钢板接合面间隙对摩擦型高强度螺栓的影响

钢板的制造和安装偏差导致的接合面间隙对摩擦型高强度螺栓产生的摩擦力有一定的削弱作用。针对某大型锅炉大板梁下翼缘的拼接,通过有限元分析,分别探讨了螺栓数目、螺栓性能等级和公称直径以及连接板和被连接板厚度的改变等因素对摩擦力的影响以及摩擦力损失值与这些因素之间的变化规律,并给出了考虑这些因素影响后修正的摩擦型高强度螺栓承载力设计值公式,建议在摩擦型高强度螺栓连接的计算中,直接将接合面间隙对摩擦型高强度螺栓摩擦力的削弱考虑进去。

EFFECTS OF INTERFACE GAP BETWEEN STEEL SHEETS ON HIGH-STRENGTH FRICTION BOLTS

Gaps between steel sheets due to manufacturing and/or installation error may cause some loss in friction produced by high strength friction boltsIn this paper,such effects were analyzed by finite element method,against a background of connection design of the lower flange for the girder of a heavy boilerThe effects of a series of factors on friction were investigated,including the number of bolts,the performance grades and diameters of bolts,and the thickness change of connecting and connected platesA modified formula for capacity design of high strength friction bolts considering these factors is proposed,so that loss of friction due to interface gap can be taken into account in the design of high strength friction bolts connection