高强钢螺栓连接电弧热喷铝接触面抗滑移系数试验研究

Experiment study on slip coefficient of high strength steel bolt connection arc thermal spraying aluminum contact surface

高强钢结构对连接承载力的要求提高,为在高强钢结构中应用高强度螺栓摩擦型连接,需改进接触面处理方式以提高抗滑移系数。电弧热喷铝是一种新的接触面处理方式,其抗滑移系数较高,但目前电弧热喷铝接触面相关研究较少,应用于高强钢结构时缺少设计依据。针对Q460C,Q460D,Q890C三种牌号的高强钢,以及电弧热喷铝、轧制表面砂轮除锈和轧制表面钢丝刷除锈三种接触面处理方式,进行了7组高强度钢材螺栓摩擦型连接试件的抗剪试验,分析了钢材强度、板件厚度、螺栓预拉力及接触面处理方式对抗滑移系数的影响。试验结果表明:荷载引起的10.9级高强度螺栓预拉力损失可达10%以上,经电弧热喷铝处理过的高强度钢材接触面抗滑移系数可达0.71,设计中建议按最小值取0.60。

The resistance of the connections is required to be increased in high strength steel structures.In order to apply slip-critical design of high strength bolted friction-type connection in high strength steel structures,the contact surface treatments should be improved to increase the slip coefficient.Arc thermal spraying aluminum is a new method of contact surface treatment that may develop higher slip coefficients,but there are little investigations on the arc thermal spraying aluminum contact surface and a lack of design basis in high strength structures.A total of 7 groups of high strength steel bolted connection friction-type connection specimens,with three steel grades of Q460C,Q460D and Q890C,considering three contact surface treatments of arc thermal spraying aluminum,rust removal with grinder,and rust removal with wire brush were tested.The influences of steel strength,plate thickness,bolt pretension and contact surface treatment on slip coefficients were analyzed.According to the results,the pretension loss of 10.9 grade high strength bolts caused by force could be more than 10%,and the slip coefficient with arc thermal spraying aluminum contact surface,which could reach 0.71,is recommended to be 0.60 in design.