APPARATUS AND METHOD FOR CONSTRUCTING COMPACTED GRANULAR OR STONE COLUMNS IN SOIL MASSES

摘要

COMPACTED GRANULAR OR STONE COLUMNS ARE CONSTRUCTED IN SOIL TO INCREASE THE LOAD-BEARING CAPACITIES OF THE NATIVE SOIL. AN ELONGATED HOLLOW TUBULAR MEMBER (12) IS PENETRATED DOWN INTO THE SOIL TO A PREDETERMINED DEPTH AND THEN THE GRANULAR MATERIAL OR STONE FOR CONSTRUCTING THE COLUMN IS FED DOWN THROUGH THIS MEMBER AND OUT THE LOWER END (14) THEREOF WHERE IT IS THEN DRIVEN OUTWARDLY IN A RADIAL DIRECTION BY AN IMPELLER (16) WHICH IS EXPOSED, AT LEAST IN PART, AT THE LOWER END (14) OF THE TUBULAR MEMBER, AS THE HOLLOW TUBULAR MEMBER (12) IS EITHER PENETRATING OR BEING WITHDRAWN FROM THE SOIL AT A PREDETERMINED RATE TO THEREBY FORCEABLY COMPACT THIS GRANULAR OR STONE MATERIAL IN A SUBSTANTIALLY RADIAL DIRECTION TO CONSTRUCT A STONE COLUMN. SUFFICIENT FORCES MAY BE APPLIED BY THE IMPELLER (16) TO THE GRANULAR OR STONE MATERIAL TO FRACTURE THE SURROUNDING SOIL.(FIG 6)