The purpose of the present invention is to provide an artificial ground freezing method having good coolant thermal efficiency without a gas-phase coolant being released into the ground or into the air. For that purpose, the present invention has: a freeze pipe (1: casing) for freezing the ground buried in the ground and a coolant circulation pipe (2) provided on the inside of the freeze pipe (1), wherein the coolant flowing inside the coolant circulation pipe (2) is carbon dioxide; and a coolant apparatus (10) that cools and supplies the carbon dioxide to the coolant circulation pipe (2), the coolant circulation pipe (2) comprising a first coolant circulation pipe (2A) on which a plurality of micro-coolant passages (2A delta) is formed, wherein the tip portion (tip portion in the ground) of the first coolant circulation pipe (2A) is connected to a plugging member (3: bottom socket) that connects the plurality of micro-coolant passages (2A delta) of the first coolant circulation pipe (2A) to a coolant supply side and coolant return side.

The purpose of the present invention is to provide an artificial ground freezing method having good coolant thermal efficiency without a gas-phase coolant being released into the ground or into the air. For that purpose, the present invention has: a freeze pipe (1: casing) for freezing the ground buried in the ground and a coolant circulation pipe (2) provided on the inside of the freeze pipe (1), wherein the coolant flowing inside the coolant circulation pipe (2) is carbon dioxide; and a coolant apparatus (10) that cools and supplies the carbon dioxide to the coolant circulation pipe (2), the coolant circulation pipe (2) comprising a first coolant circulation pipe (2A) on which a plurality of micro-coolant passages (2A delta) is formed, wherein the tip portion (tip portion in the ground) of the first coolant circulation pipe (2A) is connected to a plugging member (3: bottom socket) that connects the plurality of micro-coolant passages (2A delta) of the first coolant circulation pipe (2A) to a coolant supply side and coolant return side.

Disclosed is a method for introducing a liquid, preferably aqueous, into a volume of a porous medium (typically clay or clay-rich soil), which has a matrix hydraulic conductivity below 10.sup.−7 m/s, comprising establishing at least one frozen section and at least one non-frozen section of said volume and introducing said liquid into said non-frozen section. Also disclosed is a method for remediation of a volume of such a porous medium as well as a system/assembly suitable for carrying out said method.

Disclosed is a method for introducing a liquid, preferably aqueous, into a volume of a porous medium (typically clay or clay-rich soil), which has a matrix hydraulic conductivity below 10.sup.−7 m/s, comprising establishing at least one frozen section and at least one non-frozen section of said volume and introducing said liquid into said non-frozen section. Also disclosed is a method for remediation of a volume of such a porous medium as well as a system/assembly suitable for carrying out said method.

A pile (100) includes a first elongated hollow body (101) having a first end and a second end, the first end being closed by an end member (103) provided with an opening (104). The pile (100) includes a second elongated hollow body (102) having a first end and a second end, the second elongated hollow body (102) being arranged inside the first elongated hollow body (101) so that the first end of the second elongated hollow body (102) extends through the opening (104) and is attached to the end member (103). A method is for installing a pile (100) into the ground.

An apparatus for freezing ground comprises a freezing head extending along a longitudinal axis, and a first conduit for introducing a first cooling medium or a second cooling medium different therefrom into an interior of the freezing head. The first conduit opens into the interior a second conduit introduces the second cooling medium into the interior of the freezing head or draws the first and/or the second cooling medium off from the interior of the freezing head. The second conduit opens into the interior of the freezing head, the apparatus has at least three separate connections, namely a first connection, via which the first cooling medium can be introduced into the interior of the freezing head, a second connection, via which the second cooling medium can be introduced into the interior of the freezing head, and a third connection, via which the first or the second cooling means can be drawn off from the interior of the freezing head.

An apparatus for freezing ground comprises a freezing head extending along a longitudinal axis, and a first conduit for introducing a first cooling medium or a second cooling medium different therefrom into an interior of the freezing head. The first conduit opens into the interior a second conduit introduces the second cooling medium into the interior of the freezing head or draws the first and/or the second cooling medium off from the interior of the freezing head. The second conduit opens into the interior of the freezing head, the apparatus has at least three separate connections, namely a first connection, via which the first cooling medium can be introduced into the interior of the freezing head, a second connection, via which the second cooling medium can be introduced into the interior of the freezing head, and a third connection, via which the first or the second cooling means can be drawn off from the interior of the freezing head.

A method for freezing and treating a mass of soil, making it possible to compensate for deformations of the mass of soil during thawing, including the following steps: a) producing at least one bore (2) in the mass of soil, b) at least partly freezing the mass of soil using a freezing fluid injected into the bore, and then c) injecting a compensation grouting into the mass of soil, using the bore (2) that was used for freezing, during the thawing phase in order to at least partly compensate for variations in the volume of the mass of soil when the latter thaws.

A method for freezing and treating a mass of soil, making it possible to compensate for deformations of the mass of soil during thawing, including the following steps: a) producing at least one bore (2) in the mass of soil, b) at least partly freezing the mass of soil using a freezing fluid injected into the bore, and then c) injecting a compensation grouting into the mass of soil, using the bore (2) that was used for freezing, during the thawing phase in order to at least partly compensate for variations in the volume of the mass of soil when the latter thaws.

A method and device for freezing the ground are disclosed, including a freezing lance which extends along a longitudinal axis and has a pipe mantle that encloses an interior space, wherein the ground surrounding the freezing lance can be cooled by the refrigerant present in a first section of the interior space, a line for supplying the liquid refrigerant in the first section of the interior space, wherein the device has a first end section with a first opening for removing an exhaust gas formed by evaporation of the refrigerant from the interior space, wherein the interior space has a second section for holding the exhaust gas, wherein heat is exchangeable between the exhaust gas and the pipe mantle in the second section, so that the exhaust gas can be heated by heat exchange with the ground adjacent to the freezing lance.