Abstract: Hardenable foam compositions comprising oxygen-releasing foaming agents, a hardener consisting of an alkali silicate solution, a fine particle solid material which reacts with said hardener, namely an oxide mixture consisting of SiO.sub.2 and Al.sub.2 O.sub.3 extracted from a filter dust, an electrofilter ash from high-temperature power plants, and calcinated bauxite or amorphous silica, to which reaction accelerators are added, are improved, firmer, faster hardening foams. Reducing agents, in particular sulphur compounds with a reducing action are preferred. Oxidizing agents or fine particle substances such as soot or color pigments are effective.

Abstract: The present invention is directed to a process for strengthening and sealing geological formations which are moist or contain water, in particular loose stone, by the injection of a mixture which reacts to form polyurethane, characterized in that a polyisocyanate component is injected before injection of the reaction mixture.

Abstract: Method for bonding of anchoring bolts in boreholes, in which an anchoring bolt is pushed with a rotary motion into a twin-chamber cartridge, one compartment of which is filled with a polyisocyanate component and the other one with a hydroxyl component, prepolymer from the conversion of polyisocyanates with one or several difunctional polyols of the molecular weight range 800-5000, preferably 1600-3000, being used as polyisocyanate component.

Abstract: A procedure of bonding roofbolt rods to boltholes whereby the roofbolt rod is pushed under rotating movements into a bolthole filled with an adhesive mass consisting of a mix by whose reaction is obtained polyurethane, characterized in that a mass consisting of polyisocyanate-prepolymerides is used which has been prepared from polyisocynates and one or more bifunctional polyols in a molecular weight range between 800 and 5,000, preferably between 1,200 and 3,000, and which reacts in the borehole with 1 to 25% by weight (related to the mass) of water and/or polyols serving as the hydroxyl component.

Abstract: For consolidation of geological formations and artificial beds of rock, earth, and coal by means of foaming and hardening polyisocyanate/polyol blends, diols with secondary hydroxyl functions of the OH number range 150-1000 are used as diol component. Preferably a crude polyisocyanate blend (MDI) obtained by phosgenation of aniline/formaldehyde condensates which at ambient temperature assumes a liquid state, and the liquid prepolymers of said crude MDI are used as isocyanate components.

Abstract: Waterglass solutions are mixed with polyisocyanates and these emulsions are then left to harden in the formations. Introduction of the mixture into the formations which are required to be consolidated, e.g. deposits of coal, is mainly carried out by forcing the mixture under pressure into bore-holes in the formations. According to one variation of the process, the components of the mixture are introduced into the multi-chamber cartridges which are introduced into the bore-holes and then destroyed as the components are mixed. Certain additives such as accelerators, blowing agents, polyols, stabilizers and/or thixotropic agents are advantageous for the quality of the composite masses formed by hardening of the mixture.

Abstract: Waterglass solutions are mixed with polyisocyanates and these emulsions are then left to harden in the formations. Introduction of the mixture into the formations which are required to be consolidated, e.g. deposits of coal, is mainly carried out by forcing the mixture under pressure into bore-holes in the formations. According to one variation of the process, the components of the mixture are introduced into the multi-chamber cartridges which are introduced into the bore-holes and then destroyed as the components are mixed. Certain additives such as accelerators, blowing agents, polyols, stabilizers and/or thixotropic agents are advantageous for the quality of the composite masses formed by hardening of the mixture.