Abstract: An auxiliary tunneling apparatus includes a reaction force receiver and first and second split components. In the excavation of a second tunnel by a boring machine, the reaction force receiver forms a replacement face of a side wall of the second tunnel on a first tunnel side where the first and second tunnels intersect each other, and a gripper of the boring machine pushes against the replacement face. The first and second split components are installed to push against the side wall of the first tunnel, support the reaction force receiver within the first tunnel, and move back and forth with respect to the side wall of the first tunnel.

Abstract: The present invention relates to a novel easily-cuttable tunnel segment structure used for the departure of a shield machine from a main tunnel to a branch tunnel or the return to the main tunnel from the branch tunnel, and provides an easily-cuttable tunnel segment structure 1 constructed by connecting a plurality of easily-cuttable tunnel segment pieces 2 in the longitudinal direction of a tunnel, wherein at least an easily-cuttable area 3 is formed by concrete 7 in which easily-cuttable reinforcement members are arranged, and a join disposed at least in the easily-cuttable area 3 in the longitudinal direction has an easily-cuttable join structure.

Abstract: A support element for use with shotcreting to line tunnel walls with cement includes four rods secured to outer surface portions of quadrilateral reinforcement members. The longitudinal axis of pairs of adjacent rods each lie in a plane such that adjacent planes are normal to one another. Optionally, side braces may be secured to an outer surface or to an inner surface of adjacent rods.

Abstract: This invention relates to a method for boring a large-section tunnel safely and quickly by reinforcing and improving in advance the ground over the full length of the tunnel section, which includes; boring a top drift (2) through the full length of the tunnel (1) section, drilling curved holes inclined in forward or backward directions at an angle of about 45 degrees at preset intervals from the top drift (2) along the peripheral edges of the sections of the tunnel (1) by using ordinary small bore rock drills and curved steel pipes (3), pulling off the steel pipes (3) after inserting injection pipes into the drilled holes, injecting grout into the ground surrounding the tunnel through the injection pipes to develop artificial ground arches (4), excavating the tunnel (1), advancing suspension forms (6) and placing concrete for secondary lining.

Abstract: An ore pass rush eliminator is disclosed which includes, in the ore pass shaft, a channel formed in the base of the shaft whereby excess water can pass to waste to avoid any build up of such water. Further described are means whereby the channel may be kept clear of build up of ore by means of an endless chain.

Abstract: In the provision of elongate underground cavities having a large volume are to be provided, particularly in the construction of underground railroad stations having at least two stories, it is desired to avoid a need for excavating an open pit and to minimize the handling of material. This is accomplished in that the cavity is excavated and lined in a two consecutive stages. In the first stage, two laterally spaced apart galleries are driven in the longitudinal direction of the cavity by a mining technique in the region of a top segment of the desired cavity and are formed each with an outer side face, which constitutes a portion of a side face of said top segment. Only one of said galleries is driven at any given time in any given cross-section of said top segment. Each of said galleries is provided on said outer side face with a supporting permanent first lining. The ground between said two galleries is removed to complete the excavation of said top segment.

Abstract: A method of forming an underground cavern aiming at forming an underground cavern of a large scale at a very deep place in soft ground and soft rock layers safely and economically, and a tunneling machine suitable for use in carrying out the method. This method of forming an underground cavern consists of the steps of forming a ground reinforcing zone around a portion intended to be hollowed out before froming an underground cavern to be built, and then excavating the inside surrounded by the ground reinforcing zone. Further, the above-mentioned tunneling machine comprises a ring-shaped body having a first ring, a second ring, and a third ring; a boring device mounted between the second ring and propelling jacks for boring a plurality of holes extending radially from the inner surface of the tunnel into the ground; and a reinforcing material filling device mounted also between the second ring and the propelling jacks for filling a reinforcing material and a grout into each of the holes.

Abstract: The present invention relates to a method for excavating and preparation of rock cavities and then substantially spherical rock cavities or rock cavities having spherically shaped parts, such as dome-shaped ceilings, which rock cavities are intended as shelter, for the storage of solid or liquid products or for production plants in rock, whereby one drills a first series of radially outwardly extending holes (6) from a first distance (4) from one or more shafts/tunnels (3, 13, 14, 15, 16), preferably radially arranged from the center of a sphere projected; that one drills a second series of radially outwardly extending holes (8) from a second, far more out arranged distance (7) from the center, which holes (8) extend outside the holes of the first series; that one drills a third series of radially outwardly extending holes (10) from a third, further far more out arranged distance (9) from the center, which holes (10) extend outside the holes (8) of the second series; that optionally further series of holes (1

Abstract: A process for excavating and constructing a tunnel, and an excavating device are disclosed. This process is directed to excavating and constructing a tunnel under a railway or a road on a banking or on level land in the direction transverse to the railway or road. In this process, pits are dug on the opposite sides of the railway, and then an excavator digs into the wall of a pit on one side so as to go out of the wall of the other pit through the ground left therebetween. In this respect, a hollow casing unit of a box shape is coupled to the rear end of the excavator equipped with a screw conveyor. As the excavator advances or digs forwards a given distance, another casing unit is in turn coupled to the rear end of the preceding casing unit, and then such a step is repeated, until the excavator goes out of the wall of another pit. In this manner, the excavator further digs into the wall of one pit in the position adjacent to the preceding run of casing units.

Abstract: A rectangularly shaped tunnel is constructed to include an artificial roof, side wall pillars, a center wall pillar and floor portions all extending along the length of tunnel. The artificial roof is formed by sequentially excavating cross cut shafts and by subsequently plugging the thus formed cavities with concrete. Then the portions directly beneath opposite sides and the center of the roof are excavated and filled with concrete to form side wall pillars and a center wall pillar. Thereafter the rock portions covered by the roof and the wall pillars are excavated to form inner hollow tunnel chambers, the bottoms of which are covered by concrete to form floor portions. Iron frames are embedded in the concrete.