1. School of Environmental Science,Liaoning University,Shenyang　 110036,China; 2. Shenhua Xinjiang Energy Co. ,Ltd. ,Wulumuqi　 830027,China; 3. College of Mechanics and Engineering,Liaoning Technical University,Fuxin　 123000,China

U型钢支架接头摩擦性能是影响U型钢支护性能的重要因素之一,在冲击地压载荷作用下,常因接头处U型钢与卡缆的摩擦关系差,导致U型钢支架的承载力远未达到理论承载力,支架便发生结构失稳破坏。通过自制的摩擦性能测试装置对不同材料间的摩擦性能进行测试,得到不同预紧扭矩条件下钢板与钢板、钢板与软金属板、钢板与橡胶板间相互滑动过程中的摩擦力以及摩擦因数变化规律,结果表明:在轴向压力作用下,钢与钢间摩擦力达到最大静摩擦力后将突然降低,造成接头处承载力发生突降,不利于支架稳定;钢与软金属间发生滑动时,承载力变化比较平稳;钢与橡胶间发生滑动时,随着滑动距离的增加,摩擦力持续降低,且波动较大;钢与软金属间的摩擦因数要大于钢与钢、钢与橡胶间的摩擦因数,在接触面间相对滑动位移相等的条件下,使得接头处吸收的能量更多。研究表明在O型棚支护接头处垫放软金属板,可有效提高接头处的摩擦性能,提高U型钢支架的承载力和抗冲性能。

The friction performance of U-shape steel support joints is one of the important factors that affect the support performance. Under the impact ground pressure loading,the friction relationship between the U-shape steel and the ca-ble is often poor,which leads to the failure of the U-shape steel bracket to reach the theoretical bearing capacity,and the structural instability and failure of the support will occur. The friction properties of different materials are tested by the self-made device for testing friction performance,and the friction force and the change law of friction coefficient in the sliding process of steel plate and steel plate,steel plate and soft metal plate,steel plate and rubber plate under dif-ferent pre-tightening torque conditions are obtained. The results show that under axial pressure the frictional force be-tween steel and steel will decrease suddenly after reaching the maximum static frictional force,resulting in a sudden drop of bearing capacity at the joint,which is not conducive to the stability of the support. When the steel and soft metal slide,the bearing capacity changes more smoothly. When the sliding occurs between steel and rubber,the frictional force decreases and fluctuates with the increase of sliding distance. The friction coefficient between steel and soft metal is greater than that between steel and steel,steel and rubber plate. Under the condition of the same relative sliding dis-placement between contact surfaces,more energy is absorbed at the joints. The above research indicates that the soft metal plate is placed at the joint of the O-shape shed support joint,which can effectively improve the friction properties at the joint and improve the bearing capacity and the impact resistance of the U-shape steel support.

XU Lianman,PAN Yishan,CHEN Jianqiang,et al. Experimental study on friction properties and optimization of U- shape steel support joints[J]. Journal of China Coal Society,2018,43(11):2992-2998.