Injection apparatus for foundation piles

Abstract From the Canadian patent

The invention concerns an apparatus and a method for forming underground piles. Apparatus is provided comprising a tube having holes at least near its lower end for introducing first stage grout into a borehole, and means for injecting second stage grout under pressure to infiltrate the first stage grout and enhance and reinforce its action. Second stage grout is injected through an inner coaxial tube having at its lower end, a reservoir pad which splits open longitudinally along lines of weakness or partial slits to release second stage grout suddenly. The force of second stage grout may expand the bottom of the tube for first stage grout thus further improving the anchor. The tube for …