Soil grouting process

Claim 2

The method of claim 1 wherein the gelling agent is sodium silicate.

Claim 3

The method of claim 1 wherein the polyphenolic material is selected from the group consisting of the vegetable tannin extracts of mimosa, quebracho, mangrove and wattle.

Claim 4

The method of claim 1 wherein the polyphenolic material is selected from the group consisting of the catechin extracts of acacia catechu, acacia suma and mahogany wood.

Claim 5

The method of claim 1 wherein the polyphenolic material is selected from the group consisting of the alkaline extracts of the barks of Western Hemlock, Douglas Fir, Sitka Spruce and Southern Yellow Pine.

Claim 6

The method of claim 1 wherein the polyphenolic material is the extract of mimosa.

Claim 7

The method of claim 1 wherein said gelling agent is selected from the group consisting of vanadium pentoxide, potassium vanadate, sodium vanadate, lithium vanadate and ammonium vanadate.

Claim 8

The improved soil-grouting process which comprises injecting into soil to be stabilized and/or strengthened, an aqueous alkaline gel-forming composition consisting essentially of a mixture of polyphenolic material selected from the group consisting of the vegetable tannin extracts of mimosa, quebracho, mangrove and wattle, catechin tannins and the alkaline extracts of coniferous barks, dispersed in sufficient water to form a 2 to 45 percent solution by weight, said polyphenolic material being substantially soluble in alkaline aqueous solution, being capable of rapid gelation and having a formaldehyde combining capacity of at least 5.0; from 5 to 30 percent of formaldehyde based on weight of dry polyphenolic material; and a gelling compound soluble or colloidally dispersible in said aqueous composition which provides in the composition a complexing element selected from the group consisting of silicon, vanadium, molybdenum, manganese, titanium, copper, zinc or zirconium, the amount of said complexing element in said composition being within the range of from about 0.01 to 10 percent based on the dry weight of the solid polyphenolic material, said composition being thoroughly mixed before injecting it into the soil, said complexing element being proportioned to effect the gelling rate.

Claim 9

The process for preparing a gel in association with a mass of solid particles which process comprises: intermixing a vegetable tannin extracted from mimosa with sufficient water to form a 7-23 percent solution by weight; intermixing with said solution from 15 to 25 percent of paraformaldehyde based on the dry weight of mimosa extract and a gelling compound soluble or colloidally dispersible in said solution in amount sufficient to provide from 0.1 percent to 6.5 percent based on dry weight of mimosa extract of a complexing element of the group consisting of silicon and vanadium, said element accelerating the gel-forming reaction of the composition, said element being selected in such an amount as to control the gelling rate at the temperature of said solid particles; and promptly before any appreciable reaction takes place, injecting the intermixed components into the mass of solid particles to form a stable gel structure.