US 4,014,174 A · Method of simultaneously strengthening the surface of a borehole and bonding cement thereto and method of forming cementitious pilings

Abstract

An improved method of consolidating the surface of a borehole in an incompetent formation and simultaneously strengthening the bond between the surface of the borehole and cement placed in the borehole is achieved by forcing an aqueous solution of a multivalent cation salt into the formation, thereafter forcing an alkali metal silicate solution which has a pH less than 12.0 containing at least 12% by weight silica into the formation, and thereafter forcing an aqueous cement slurry containing at least 2% by weight of a water soluble multivalent cation salt to contact the surface of the borehole. A cementitious piling intimately bonded to the formation is prepared by filing the stabilized borehole with an aqueous cement slurry and allowing the cement to harden.

Claims10

Dependent claims

A method for simultaneously consolidating the surface of a borehole and bonding cement to the surface of said borehole, which comprises:

a. placing an aqueous salt solution containing at least 0.5% of a multivalent cation salt into a borehole;
b. forcing said salt solution into the formation surrounding said borehole;
c. displacing said salt solution from said borehole;
d. placing an alkali metal silicate solution which has a pH less than 12.0 containing at least 12 percent by weight silica within said borehole;
e. forcing said silicate solution into said formation;
f. displacing said silicate solution from said borehole;
g. placing an aqueous cement slurry containing at least 2 percent by weight of a water soluble multivalent cation salt within said borehole;
and
h. forcing said cement to contact said surface of said borehole.

6 more elements

Dependencies are inferred from the claim text.

Method of simultaneously strengthening the surface of a borehole and bonding cement thereto and method of forming cementitious pilings

Life of this patent

Method of simultaneously strengthening the surface of a borehole and bonding cement thereto and method of forming cementitious pilings

Life of this patent

Abstract

Claims10