Polymer grouting method for constructing gravel pile

Abstract

A polymer grouting method for constructing gravel pile for reinforcing the soft and special soil foundation includes steps of: (1) pile-position-pore-forming; (2) installing a grouting pipe; (3) putting graded stones; (4) polymer lifting grouting; and (5) pile-forming. By pile-position-pore-forming, putting graded stones, polymer lifting grouting in the reinforcement site and other steps, the injected two-component expansive polymer material expands rapidly after a chemical reaction, and then is solidified with the graded stones for filling in the pile hole from below to above, the blast hole wall rock-soil is expansive compacted and fully integrating with the surrounding rock-soil, thus forming the polymer gravel pile. The present invention can rapidly reinforce the soft and special soil foundation, thereby providing an advanced, highly efficient, safe and practical method for reinforcing the soft and special soil foundation. It has great economic and social benefits and broad development prospects.

What is claimed is: 
     
         1 . A polymer grouting method for constructing gravel pile, comprising steps of:
 (1) pile-position-pore-forming: according to design requirements, constructing a pile hole at a pile position by a drilling tool, whose depth reaches a design depth;   (2) installing a grouting pipe: installing a grouting pipe in the pile hole, wherein the grouting pipe is located in a middle of the pile hole, and a grouting outlet of the grouting pipe is close to a bottom of the pile hole;   (3) putting graded stones: according to different geological conditions, putting graded stones into the pile hole;   (4) polymer lifting grouting: putting a polymer lifting grouting control equipment on a hole of the grouting pipe; placing the grouting pipe into a pipe fixing device of the polymer lifting grouting control equipment; injecting two-component expansive polymer material to the pile hole via the grouting pipe by a polymer grouting system, and simultaneously opening the lifting grouting control equipment; and   (5) pile-forming: upwardly lifting the grouting pipe according to the set rate, the injected two-component expansive polymer material expanding rapidly after a chemical reaction, and solidifying with the graded stones for filling in the pile hole from below to above, expansion compacting a blast hole wall rock-soil and fully integrating with a surrounding rock-soil, thus forming a polymer gravel pile.