Bolt as an " active " supporting means, with its unique supporting mechanism, simple construction process and good economic benefits, in supporting in underground engineering structure gets more and more extensive application.

In a more complex and difficult in deep soft rock roadway deformation control, is a very important way of supporting. At present, coal mine bolt support design method including engineering analogy method, the theoretical calculation method, numerical calculation method and combining with the field monitoring based on dynamic information feedback design method. However, at present a lot of our country area or to the empirical method, coupled with complicated surrounding conditions of randomness and anchor rod construction process concealment, the bolt supporting parameters are difficult to identify, bolting rationality, safety can be guaranteed. Therefore, the mechanism of bolting support and bolt support parameters of in-depth study, is to ensure that the key to the success of bolt supporting technology. Bolt and anchor length of cable anchor supporting parameters in the design of key parameters of domestic and foreign literature, but did not give the length design of bolt and anchor of the exposed length of the scientific definition, resulting in different mining operations for a prescribed #118alue did not form a unified, with large difference.

In view of this, this article to anchor the exposed length of the definition and determination were studied, and the bolt and anchor length design formula is perfect. The above is the Shandong with the Swiss mining science and technology limited company for the general support of our customers finishing provided information, hope to help everyone understand!