Yieldable Bearing Block

Abstract

A mine roof bolting system including a bearing member having a first member, a second member spaced apart from the first member, and apertures defined through each of the first and second members, and a mine roof bolt extending through the apertures. When a load is applied to the mine roof bolting system, the bearing member yields or deforms. Also, a method for providing a roof support in an underground mine including providing the bearing member and inserting a mine roof bolt through the apertures of the bearing member and into a borehole in a mine roof, wherein the bearing member yields upon application of a load in excess of a predetermined load.

The invention claimed is: 
     
         1 . A mine roof bolting system comprising:
 a bearing member including a first member, a second member spaced apart from the first member, and apertures defined through each of the first and second members; and   a mine roof bolt extending through the apertures,   wherein when a load is applied to the mine roof bolting system, the bearing member yields.   
     
     
         2 . The mine roof bolting system of  claim 1 , wherein a gap is provided between the first member and the second member and wherein when a predetermined load is applied to the mine roof bolting system, the gap is reduced. 
     
     
         3 . The mine roof bolting system of  claim 2 , wherein the gap provided between the first member and the second member is at least 1 inch. 
     
     
         4 . The mine roof bolting system of  claim 1 , wherein the bearing member comprises a rectangular steel tube. 
     
     
         5 . The mine roof bolting system of  claim 1 , wherein the mine roof bolt is a cable bolt, a solid bolt, an expandable bolt, or a hollow bolt. 
     
     
         6 . The mine roof bolting system of  claim 1 , further comprising a bearing plate having a bearing surface for contacting rock strata, a contact surface positioned opposite the bearing surface for engaging the bearing member, and an aperture defined through the bearing plate. 
     
     
         7 . A mine roof bolting system comprising:
 a bearing member comprising:
 a first member defining a first aperture; 
 a second member spaced apart from the first member and defining a second aperture; and 
 a web extending between the first member and the second member and thereby defining a gap between the first member and the second member; and 
   a mine roof bolt extending through the first and second apertures of the bearing member.   
     
     
         8 . The mine roof bolting system of  claim 7 , wherein the mine roof bolt is a cable bolt, a solid bolt, an expandable bolt, or a hollow bolt. 
     
     
         9 . The mine roof bolting system of  claim 7 , further comprising a bearing plate comprising a bearing surface for contacting the mine roof, a contact surface for contacting the bearing member, and an aperture through which the mine roof bolt extends. 
     
     
         10 . The mine roof bolting system of  claim 7 , wherein the first member is substantially parallel to the second member. 
     
     
         11 . The mine roof bolting system of  claim 7 , further comprising another web extending between the first member and the second member, the two webs being spaced apart by the gap. 
     
     
         12 . The bearing member of  claim 11 , wherein, when taken together, the first member, the second member, the first web, and the second web define a central cavity. 
     
     
         13 . A method for providing a roof support in an underground mine, the method comprising the steps of:
 providing a bearing member including a first member, a second member spaced apart from the first member, and apertures defined through each of the first and second members; and   inserting a mine roof bolt through the apertures of the bearing member and into a borehole in a mine roof, wherein the bearing member yields upon application of a load in excess of a predetermined load.   
     
     
         14 . The method for providing a roof support of  claim 13 , wherein the mine roof bolt is a cable bolt, a solid bolt, an expandable bolt, or a hollow bolt. 
     
     
         15 . The method for providing a roof support of  claim 13 , further comprising positioning a bearing plate in between the mine roof and the yieldable bearing member.