Abstract: Described is a method for the trenchless underground laying of pipes. According to said method, a shield tunnel boring machine and then subsequently pipes are driven through the ground starting from a starting shaft. The shield tunnel boring machine produces a borehole whose diameter is slightly greater than the outer diameter of the pipes. The annular space between the borehole wall and the pipes thereby obtained is filled with a supporting and lubricating agent. During advance, a continuous and periodical examination of the composition of the ground is carried out in the area of the shield tunnel boring machine or the first pipe following the shield tunnel boring machine or the first lubricating point. Depending on the result of the examination, the ground in the examined area is sealed off and/or solidified by a sealing and/or solidifying agent and/or the composition of the supporting and lubricating agent is adjusted.

Abstract: Described is a method for the trenchless underground laying of pipes. According to said method, a shield tunnel boring machine and then subsequently pipes are driven through the ground starting from a starting shaft. The shield tunnel boring machine produces a borehole whose diameter is slightly greater than the outer diameter of the pipes. The annular space between the borehole wall and the pipes thereby obtained is filled with a supporting and lubricating agent. During advance, a continuous and periodical examination of the composition of the ground is carried out in the area of the shield tunnel boring machine or the first pipe following the shield tunnel boring machine or the first lubricating point. Depending on the result of the examination, the ground in the examined area is sealed off and/or solidified by a sealing and/or solidifying agent and/or the composition of the supporting and lubricating agent is adjusted.

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: The manufacture of extended, inaccessible holes for underground ducts, conduits and the like is performed by a closed construction process, wherein the preferably remotely-controlled excavation is performed and following that a structure is installed which is employed as the product duct, conduit or the like. The installed structure is provided by injection of an injection material under pressure into an annular space between a form following the excavating apparatus and the ground to manufacture at least one endless inner wall for the hole which then serves as the underground duct, conduit or the like. The novel apparatus of this invention correspondingly comprises a form following the required excavation mechanism conformed to form an annular space between the form and the ground, that form having a form front closing the form and at least one inlet therein for injection of an injection material into the annular space.