Composite self-drilling soil nail and method

Abstract

A subsurface support comprises a soil nail having an outer member and an inner member placed within the outer member. Features are provided to maintain a uniform spaced relationship between the inner and outer members. The spaced relationship may be achieved by crimping the outer member, or by use of an insert installed between the inner and outer members. In another embodiment, the support is made of composite construction materials, and having a self-drilling capability. The outer member may be fiberglass, and a metallic drill bit may be secured to a distal end of the soil nail. The inner member is preferably steel. A method is also provided to improve pull-out capacity by galvanizing the inner and outer members.

1 - 9 . (canceled) 
     
     
         10 . A method of improving the pull-out capacity and adhesion of a soil nail, said method comprising:
 providing a soil nail including an outer tubular member;   providing a galvanizing tank having a molten metal therein;   maintaining dross of the molten metal and disbursing the dross by stirring the molten metals;   dipping the outer tubular member into the molten metal wherein upon cooling, said outer tubular member has a rough surface comprising a layer of applied metal and dross particles.   
     
     
         11 . A method, as claimed in  claim 10 , further including:
 said dipping step further includes dipping an inner member into the molten metal so that said inner member has a rough surface comprising the layer of applied metal and dross particles; and   placing the inner member within the outer tubular member.   
     
     
         12 . A method of installing a soil nail into an earthen ground, comprising:
 providing a soil nail including an outer tubular member;   providing a galvanizing tank having a molten metal therein;   maintaining dross of the molten metal and disbursing the dross by stirring the molten metals;   dipping the outer tubular member into the molten metal wherein upon cooling, said outer tubular member has a rough surface comprising a layer of applied metal and dross particles;   taking the cooled soil nail and securing the soil nail to a launching device;   launching the soil nail from the launching device wherein compressed gas within the launching device forces the soil nail to be separated from the launching device and driven into the ground.   
     
     
         13 . A method, as claimed in  claim 12 , further including:
 said dipping step further includes dipping an inner member into the molten metal so that said inner member has a rough surface comprising the layer of applied metal and dross particles;   placing the inner member within the outer tubular member; and wherein   said launching step further includes launching the soil nail comprising the outer tubular member and the inner member.