An economical high-strength quick-hardening grouting material includes ordinary Portland cement, a quick-hardening sulphoaluminate gelling agent and water. The ratio of the mass of water to the sum of the mass of the ordinary Portland cement and the mass of quick hardening sulphoaluminate gelling agent is 0.46:1. The ratio of the mass of the quick-hardening sulphoaluminate gelling agent to the mass of the ordinary Portland cement is (0.67-1.5):1. The initial setting time of the grouting reinforcement material is 405 min, and the average compressive strength of a cube solidified for 4 hours is higher than or equal to 10 MPa.

A method of limiting or reducing liquid and/or gas inflow through a porous matrix, comprising delivering to said porous matrix a coagulable polymer emulsion or colloid for contacting with at least one selected additive which interacts with said polymer emulsion or colloid to form a sealing barrier to reduce liquid and/or gas inflow through the porous matrix wherein said coagulable polymer emulsion or colloid contains at least one selected additive including one or a combination of radiation stabilisers to confer radiation resistance; and wherein said sealing barrier is formed by contacting said polymer emulsion or colloid with a further selected additive to cause coagulation of said polymer emulsion or colloid to form said sealing barrier. The sealing composition, which has low toxicity, preferably contains carbon black as radiation stabiliser conferring radiation resistance for the sealing barrier in the range 1 to 100 MRad.

A soil stabilization method of forming an admixture of at least one hydrogel precursor and urease enzyme, and contacting at least a portion of the admixture with soil, and forming a hydrogel network in-situ within at least a portion of the soil, wherein at least a portion of the hydrogel network includes in-situ precipitated calcium carbonate. In some embodiments, at least a portion of the hydrogel network is formed in-situ by polymerizing the at least one hydrogel precursor in the presence of the urease enzyme.

The present invention relates to the use of a composition for stabilizing a geological formation in oil fields, gas fields, water pumping fields, mining or tunnel constructions. The composition has a hardening temperature in the range from about 40 C. to about 120 C. and can therefore be used to stabilize a geological formation in oil fields, gas fields, water pumping fields as well as in mining or tunnel constructions.

A soil stabilization method of forming an admixture of at least one hydrogel precursor and urease enzyme, and contacting at least a portion of the admixture with soil, and forming a hydrogel network in-situ within at least a portion of the soil, wherein at least a portion of the hydrogel network includes in-situ precipitated calcium carbonate. In some embodiments, at least a portion of the hydrogel network is formed in-situ by polymerizing the at least one hydrogel precursor in the presence of the urease enzyme.

A method for improving the mechanical and hydraulic characteristics of foundation grounds of existing built structures, includes the following steps: a first step of two-dimensional or three-dimensional sensing of at least one portion of the built structure; a step of identifying at least one region of intervention in the foundation ground beneath the at least one portion sensed in the first sensing step; and a step of injecting, through holes provided at least at a part of the intervention region, a cement or synthetic mix. The method further includes second steps of two-dimensional or three-dimensional sensing, mutually spaced in time, of the at least one portion during the injection step; and a step of interrupting the injection step on the basis of the information gathered during second steps of two-dimensional or three-dimensional sensing of the at least one portion.

The present invention relates to the use of a composition for stabilizing a geological formation in oil fields, gas fields, water pumping fields, mining or tunnel constructions. The composition has a hardening temperature in the range from about 40 C. to about 120 C. and can therefore be used to stabilize a geological formation in oil fields, gas fields, water pumping fields as well as in mining or tunnel constructions.

A method of limiting or reducing liquid and/or gas inflow through a porous matrix, comprising delivering to said porous matrix a coagulable polymer emulsion or colloid for contacting with at least one selected additive which interacts with said polymer emulsion or colloid to form a sealing barrier to reduce liquid and/or gas inflow through the porous matrix wherein said coagulable polymer emulsion or colloid contains at least one selected additive including one or a combination of radiation stabilisers to confer radiation resistance; and wherein said sealing barrier is formed by contacting said polymer emulsion or colloid with a further selected additive to cause coagulation of said polymer emulsion or colloid to form said sealing barrier. The sealing composition, which has low toxicity, preferably contains carbon black as radiation stabiliser conferring radiation resistance for the sealing barrier in the range 1 to 100 MRad.