Abstract:

For the roadway which required slope expansion during the service period, in order to avoid refilling bolts after the slope expansion, we developed a new type of bolt which can be used in roadside support. Rigid long threaded bolt which is made of metal rod body, rod connector, connecting bolt and high-strength long-threaded bolt tail. According to the field test, its overall tensile performance is the same to the common steel bolt of the same diameter. In Zhaogu Two Mine, Jiaozuo Coal Group, we did field tests, meanwhile the deep basic points displacement monitoring and surface displacement monitoring of the test roadway was carried out. The monitoring results show that the supporting effect of rigid long threaded bolt is superior to the supporting effect of common cable anchor. For the roadway which required slope expansion during the service period, due to the rigid long threaded bolt has high-strength long-threaded bolt tail, so after the slope expansion, continue to tighten the nut, and cut off the excess part can be. It can make full use of the existing roadside support, avoid refilling bolts, not only can save a large number of slope expansion costs, but also can shorten the time of repairing the roadway.

Key words: rigid long threaded bolt, high-strength long-threaded bolt tail, supporting effect, slope expansion