THE MECHANISM OF THE NEW-TYPE YIELDING BOLT

The soft rock project with large deformation is characteristic of large stress released in the excavation and of large deformation in the construction process. Using the traditional rock bolt support, the large deformation of the rock mass may lead to a large tension, and make the rock bolt fracture. A new-type yielding bolt for soft rock projects with large deformation is proposed in this paper. This yielding bolt is a pressure dispersion-type yielding bolt, and contains a yield supporting device at the bottom of the bolt. The supporting mechanism of the yielding bolt includes three stages, and the yield force value is determined by experiments. The yielding bolt not only disperses the stress in the anchoring body, but also generates a yield deformation, so it could be applied to soft rock projects with large deformation.