中文摘要：

为了研究U型钢可缩性支架缩动让压特性,基于支架搭接部分的受力特征,采用理论分析和室内试验研究了U型钢可缩性支架的缩动条件和缩动规律,并对影响其缩动特性的因素进行了分析。研究结果表明：支护过程中U型钢间接触力从卡缆安装位置逐渐向两端减小,其缩动过程可分为三个阶段,分别为弹性压缩阶段、小滑移阶段和滑动阶段,小滑移阶段主要克服摩擦力作用,位移较小,而滑动阶段在较小轴力变化作用下U型钢产生较大位移;支架的抗缩动能力随着卡缆预紧力的增大而增强,但随着卡缆距施力端距离的增大而减弱。在现场应用中可以通过提高卡缆扭矩,增加受力端卡缆个数以及调整卡缆安装位置来改善支架的抗缩动能力,进而提高支架的支护强度。

英文摘要：

To research the yielding characteristics of U- steel support,theoretical analysis and laboratory tests are used to study the yielding condition and law based on the mechanical characters of the overlapping part in U- steel support,and its influencing factors are analyzed. The results show that,contact force between U- steel supports decreases gradually from the clamp installing position to the two sides of the steel; the yielding process of U- steel can be divided as elastic compression stage,small slippage stage and sliding stage. In small slippage stage,U- steel mainly overcomes the friction and the displacement is small. Large displacement occurs in sliding stage under a small axial force changing. The steel anti- yielding capacity increases with the increase of pre- tension,but decreases with the increase of distance between the clamp and the applying force part. In the filed applications,the anti- yielding capacity of U- steel support can be enhanced by increasing the torque of clamps,increasing the number of clamps near the applying part,and changing the installing position of clamps.