Patent ID: 7004684
Filing Date: 2006-02-28
Classification: E02D

Abstract:
1. A method for building a pier in a soil matrix and simultaneously reinforcing soil matrix surrounding said pier comprising the steps of: a) driving a hollow tube apparatus into said soil matrix to a desired depth by applying a static force on the upper end of said apparatus in the range of about 5 tons to 20 tons, said hollow tube apparatus characterized by a hollow tube with a shaped bottom head element for driving as a leading end probe into the soil matrix, a material discharge opening at the lower end of the hollow tube above the head element, said head element configured to provide simultaneous axial and axially transverse stress components in the surrounding soil matrix, said apparatus further including a bladder expansion section with a lateral expansion bladder positioned on the outside of the hollow tube above the bottom head element and above the material discharge opening, said hollow tube apparatus characterized by having the head element with a maximum diameter exceeding the unexpanded diameter of the bladder; b) expanding the bladder laterally away from the sides of the hollow tube to compact and displace the soil matrix adjacent thereto, said bladder characterized by generally circumferential walls fitted around the hollow tube and expandable beyond the maximum diameter of the head element; c) subsequently reversing the expansion of the bladder; d) lifting the hollow tube apparatus an incremental distance less than the distance of the desired depth while injecting solidifiable pier formation material into the region evacuated by the hollow tube apparatus and expanded bladder by discharging said material in a fluid flow through the material discharge opening into said evacuated region; and repeating sequentially steps b), c) and d) to form a pier of multiple vertically arranged incremental sections of solidified pier formation material extending upwardly from the desired depth, each section surrounded by compacted and laterally stressed soil matrix.