锚杆及其附件对预紧力转化效能影响的试验研究

Experiment study on bolt and accessories affected to conversion performances of pretension

为掌握锚杆预紧力和预紧转矩之间的转化效能规律,以大同煤矿集团有限责任公司自产锚杆及其附件为研究对象,利用室内试验研究了托盘材质、托盘类型、减磨垫片、锚杆直径和材质5个因素对转化效能的影响,结果表明:对于无减磨垫片的平托盘,其强度越高,预紧转矩转化的预紧力越大;无弧形切槽球形托盘孔口的破坏阻碍了转化效能的发挥,加工切槽后,在280 N·m转矩下转化所得预紧力提高了67.9%;增设减磨垫片后,相同转矩时平托盘和球形托盘锚杆预紧力增幅分别为38.8%和112.1%,后者效能发挥更加充分;随着锚杆直径越大,其预紧力和预紧转矩之间的转化效能降低,而锚杆材质对上述影响较为有限;巷道支护中,应优先选用"MSGLW-500-20+有弧形切槽球形托盘+专用有檐螺母+减磨垫片"的组合形式。

In order to master the conversion performances between the bolt pretension and the pretension torque, based on the bolt and the accessories made by Datong Coal Mine Group as the study object, the in-door experiments were applied to study the five factors of the tray material, type, friction-reduction gasket, bolt diameter and bolt material affected to the conversion performances. The results showed that as for the flat tray without the friction-reduction gasket, the higher strength would be and the higher pretension value would be from the pre- tension torque of the bolt. The orifice failure of the no are slot spherical tray blocked the above performances to be played. After the slot processed, the pretension obtained from the 280 N · m torque conversion would be increased by 67.9%. When the friction-reduction gasket applied,the pretension of the bolts with the plat tray and spherical tray would be increased by 38.8% and 112.1% when the torque was the same and the performances of the bolt with the spherical tray would be fully played. With the bolt diameter highly increased, the conversion performances between the pretension and pretension torque would be reduced and the bolt material would be affected to the above conver- sion performances limited. MSGLW-500-20＋ arc slot spherical tray ＋ special screw nuts with eaves ＋ friction-reduction gasket combined method should be applied to the support of the mine roadway.