Process for preparing a grouting fluid

Claim 1

A PROCESS FOR PREPARING A FLUID, SUBSTANTIALLY NON-CORROSIVE GROUTING COMPOSITION OF SELECTABLE SETTING RATE ADAPTED TO BE INJECTED INTO THE INTERSTICES OF A STRUCTURE TO BE GROUTED COMPRISING MIXING ABOUT 50 VOLUMES OF TETRAETHYL ORTHOSILICATE, ABOUT 30 VOLUME OF 95 PER CENT ETHYL ALCOHOL. AND ABOUT ONE VOLUME OF WATER, PERMITTING THE MIXTURE TO STAND AT LEAST TWENTY-FOUR HOURS THEREBY PATIALLY HYDROLYZING THE TETRAETHYL SILICATE AND INSURING EQUILIBRIUM OF THE HYDROLYSIS REACTIONS, THEN MIXING THE RESULTING PARTIALLY HYDROLYZED SOLUTION WITH AN AQUEOUS ALKALINE SOLUTION HAVING A PH OF AT LEAST 9.0 AND CONTAINING FROM ABOUT 0.01 TO ABOUT 30 PER CENT OF AN ALKALINE COMPOUND, WHEREBY THE SETTING PERIOD OF THE COMPOSITION IS VARIABLE FROM SUBSTANTIALLY INSTANTANEOUS BY MIXING WITH THE MORE CONCENTRATED ALKALINE SOLUTION TO A PERIOD OF SEVERAL DAYS BY MIXING WITH THE LESS CONCENTRATED ALALINE SOLUTION.