锚杆螺纹结构与扭矩-预紧力转化关系试验研究

锚杆预紧力是锚杆发挥其主动支护效果的关键。为提高矿井巷道支护锚杆的预紧力,研究了螺纹螺距、牙高、形状对锚杆扭矩-预紧力的转化关系规律;选取了不同锚杆螺纹螺距、螺纹牙高、螺纹形状,通过试验研究螺纹结构对锚杆扭矩-预紧力转化的影响。结果表明:螺纹螺距越大,螺纹牙高越大,锚杆扭矩-预紧力转化率越低;三角形螺纹锚杆的扭矩-预紧力转化率较高。矿井巷道使用锚杆时,为提高锚杆扭矩-预紧力转化效果,可以选取螺纹螺距1.0mm、螺纹牙高0.2mm、螺纹形状为三角形的锚杆。

Experimental study on relationship between bolt thread structure and torque-preload force

Pre-tightening force of bolt is the key to exert its active support effect.In order to improve the pre-tightening force of bolt in mine roadway support,the transformation law of bolt torque-pre-tightening force from screw pitch,tooth height and shape was studied.Different bolt thread pitch,thread tooth height and thread shape were selected to study the influence of thread structure on bolt torque-preload conversion through experiments.The results show that the bigger the pitch of threads is,the higher the thread teeth are,the lower the conversion rate of bolt torque-preload force is,and the higher the conversion rate of triangular threaded bolt torque-preload force is.When bolts are used in mine roadways,in order to improve the transformation effect of bolt torque-preload,bolts with 1.0 mm thread pitch,0.2 mm thread height and triangular thread shape can be selected.