Abstract: A Tunnel Digging Machine (TDM) is a shield machine to excavate tunnels with almost any desired cross sections including rectangular, square, sub/semi-rectangular, sub/semi-square, horseshoe/U-shaped, elliptical, circular, sub/semi circular and such sections through a variety of soil and rock strata. The TDM can be designed to dig through anything from hard rock to sand with large range of width and height configurations. The TDMs can limit the disturbance to the surrounding ground and produce a tunnel lining. The TDMs may be used as an alternative to the current conventional Tunnel Boring Machines (TBM) or continuous miners. The major advantage of the TDMs over the TBMs will be their higher speed (higher advancement rate), fully sealable face, flexibility in the desired cross-section and reduced construction costs due to the mentioned higher speed, efficiency and optimized cross-section.

Abstract: A device is provided for monitoring a geological region or a structure. The device includes: a sensor, a radio transmitter configured to transmit data obtained by the sensor, a power source configured to power the sensor and/or radio transmitter, and a housing configured to protect the power source, radio transmitter and optionally the sensor. The sensor is capable of sensing a parameter useful in determining movement within a geological region or a structure; and/or the potential for failure in a geological region or a structure. The devices may include several sensor types capable of sensing parameters such as strain, pressure, temperature, electrical conductivity, electrical resistance, or chemistry. A series of devices may be operable as a system, with at least some of the devices further functioning to relay radio signals transmitted by other devices of the system.

Abstract: A tunnel boring machine having a cutting wheel equipped with a number of excavation tools provided with sensor units and, in a corresponding tunnelling method, only substantially fully worn excavation tools are able to be replaced using a data processing device designed with an advancement planning unit by detecting the current state of the excavation tools and predicting the state of the excavation tools on tool replacement predication planes lying in the advancing direction.

Abstract: The present disclosure discloses a multi-functional intelligent tunneling apparatus and method for simulating partial excavation of tunnel. The apparatus comprises an operating platform, a multi-functional rotary tunneling system, a precision power propulsion system, an information acquiring and processing system, a digital display control box and a slurry pumping device, wherein, the multi-functional rotary tunneling system includes a plurality of independent operating channels, and can realize multi-functional simulation of a tunnel construction process, including drilling, slurry injecting, and partial excavation under real-time monitoring; under the control of the digital display control box, the precision power propulsion system can realize the fine control of the multi-functional rotary tunneling system by means of hydraulic monitoring and preset advance distance.

Abstract: An underground networking tunnel may be installed at a data center construction site prior to completion of a data center being constructed at the data center construction site. Networking equipment in the underground networking tunnel may be configured and commissioned concurrently with construction of the data center. Also data center power and cooling systems may service the underground networking subsequent to construction of a data center above the underground networking tunnel.

Abstract: The invention relates to a cutter holder (1) for a tunnel boring machine, comprising: a housing (2) comprising two cavities (26) formed in opposite walls (20), and two clamping sets (3), configured to be removably mounted on either side of the roller cutter (10) in the housing (2), and each comprising: a base plate (32), and a center wedge (34), movably mounted on the base plate (32), two side wedges (36), hinged between the base plate (32) and the center wedge (34) between a retracted position and a clamping position, wherein the side wedges (36) transversely swing and enter into the cavity (26) facing the housing (2).

Abstract: A friction bolt assembly has a tubular friction bolt body defining a cavity and having a split. A rod extends through the cavity. An expansion element is mounted on the rod at or toward the rod leading end and protrudes through the friction bolt body leading end. The expansion element has an engagement surface tapering toward the rod trailing end. A drive head is mounted on the rod at or adjacent the rod trailing end. The rod is actuatable by rotation of the drive head to draw the expansion element toward the friction bolt body trailing end such that the engagement surface engages the friction bolt body, radially outwardly deforming the friction bolt body.

Abstract: An inline mounting assembly for a TBM cutter assembly includes first and second housing mounts, having upper and lower ear portions, and an inline channel sized to receive an end of the cutter assembly. The housing mounts include a first guide and a second guide defining forward and rearward abutment faces. A wedge assembly includes a bolt that extends through the first guide and engages a wedge configured to clamp the cutter shaft to the housing mount. A back support assembly includes a clamp block that abuts the rearward abutment face, a bridge block that abuts the forward abutment face, and a bolt that extends through the blocks. The bridge block abuts the shaft to provide support.

Abstract: There are provided using high power laser systems for performing decommissioning welding and repair of structures in boreholes, off-shore, and other remote and hazardous locations. In a particular embodiment the laser system is a Class I system.

Abstract: A method of constructing a shaft in the earth for use as, for example, a launch shaft or a retrieval shaft, may include several steps. One step includes installing a secant pile wall into the earth. The secant pile wall encloses a portion of the earth. Another step includes excavating the portion of the earth enclosed by the secant pile wall. The excavated portion leaves an interior of the shaft and exposes an inside surface of the secant pile wall. Yet another step includes placing a metal liner within the interior of the shaft. And yet another step includes partially or more filling a space located between the inside surface of the secant pile wall and the metal liner with a grout material.

Abstract: A tunneling apparatus includes a drill head and a steering shell. The drill head includes a main body having a distal end and an oppositely disposed proximal end. The steering shell is disposed at the distal end of the drill head and is moveable relative to the main body of the drill head. The drill head includes structure that assists in maintaining a precise line even in soft drilling conditions.

Abstract: An abrasion detecting apparatus is configured to detect the abrasion of a component of a cutter head of a tunnel boring machine, which is configured to excavate ground using a cutter to bore a tunnel. The abrasion detecting apparatus includes an abrasion detection probe located rearward of a front end of the cutter by a predetermined distance and located forward or rearward of a front end of the component, whose abrasion is to be detected, of the cutter head by a predetermined distance, where the abrasion detection probe includes an abrasion detecting portion at a front end portion thereof. The abrasion detecting portion abrades away by contact with the ground to be excavated. The abrasion detecting apparatus also includes a detecting device configured to detect an abrasion of the abrasion detecting portion.

Abstract: In forming a mine shaft for an underground mine, earth excavated by a boring machine may be transported upwardly by a handling unit to a transfer station where it may be transferred into skips, which may be raised and lowered along skip guides within the shaft hole for transport of the excavated material to an earth surface region. The transfer station may be moved downwardly as excavation progresses.

Abstract: Tail seal compound (tail seal) for tunnelling machine comprising blown oils, more than 30% by weight of a mineral charge and fibrous material.

Abstract: A boring machine includes a steering head which is located behind a cutter head. The steering head has a plurality of steering openings spaced around its periphery. A steering component is mounted adjacent to each steering opening, and each steering component includes a steering paddle that is pivotally mounted with respect to the steering head so as to pivot about a paddle pivot axis. Each steering component also includes a linear actuator and a force multiplier. The linear actuator operates to direct an actuating force along a line that is parallel to the longitudinal axis of the steering head, and it cooperates with the force multiplier and the steering paddle so that upon operation of the linear actuator, a pivot force which is the product of the actuating force and a multiplier factor greater than one causes the steering paddle to pivot about the pivot axis.

Abstract: The invention relates to a method for replacing a disk cutter (1) mounted with preload in a casing (2) attached to the cutting head of a tunnel boring machine, operated using a disk cutter (1) bearing, firmly attached thereto, an element (4) for locking into the housing (2) and preloading means (5), the method involving the steps of: a) removing a worn disk cutter (1) from said housing (2): • clamping a disk cutter (1) handling device (3) onto the housing (2); • taking hold of the disk cutter, • releasing the preload, • unlocking, • extracting the disk cutter (1), • unclamping the device (3), b) fitting a replacement disk cutter (1) in reverse order.

Abstract: A guided boring machine includes a cutter head, a steering head and an internal casing with an auger therein for conveying material cut by the cutter head towards the rear end of the auger. The boring machine bores a tunnel from a launch pit to a target pit along a desired boring direction and simultaneously installing a selected one of a plurality of differently-sized product casings in the tunnel. When the internal casing is placed within a selected product casing with its internal casing longitudinal axis coincident with the longitudinal axis of the selected product casing, an annular space is formed with respect to the selected product casing. The guidance assembly includes a laser that is mounted behind the boring machine and oriented so as to direct its beam in a desired boring direction within the annular space. A target mount is mounted to the steering head inside surface. The target mount includes a roll correction slot which is parallel to the adjacent steering head inside surface.

Abstract: A tunnel drilling machine and a method for drilling an epitrochoidal tunnel is disclosed. The tunnel drilling machine includes a tunneling machine body, a fixed gear operatively coupled to a frontal end of the tunneling machine body along a central axis of the tunneling machine body, and a drill head having a substantially triangular periphery. The drill head includes an internal gear ring, the internal gear ring being mounted on the fixed gear, wherein the fixed gear drives the internal gear ring around the fixed gear with a gear ratio of 3:1 to form an epitrochoidal tunnel.

Abstract: A boring machine includes a cutter head, an internal casing and an auger that is located within the internal casing. The cutter head and the auger are operationally connected to a rotational mechanism. A rear bulkhead is located at the rear end of the auger, and a rear hopper is located behind the rear bulkhead. The boring machine also includes means for directing material cut by the cutter head into the auger so that rotation of the auger will convey such material rearwardly to the rear hopper. The boring machine includes a transverse conveyor located behind the rear bulkhead in the rear hopper which is adapted to convey material out of the rear hopper in a direction transverse to the longitudinal axis of the auger.

Abstract: Tail seal compound (tail seal) for tunnelling machine comprising blown oils, more than 30% by weight of a mineral charge and fibrous material.

Abstract: An auger boring machine includes a common power source for powering a drive motor which rotates an auger and a drive assembly which drives a pilot tube to form a pilot hole in the earth which is followed by the auger. The drive assembly is movable into and out of the operational position of the auger to allow the auger to be mounted on the drive motor. Preferably the drive assembly is removably mounted on the frame of the auger boring machine. An electric generator and hydraulic pump are powered by the common power source for operating various components of the drive assembly.

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: A method of determining a direction of a drilling pattern in tunnel curve calculation to be executed in a control unit of a rock drilling rig. The invention further relates to a storage device including software product implementing the method, and a rock drilling rig. A tunnel line of a tunnel to be excavated is determined e.g. by using curve fitting. A location of a drilling site on the tunnel line is communicated to the control unit and a navigation plane of the drilling pattern is positioned on the tunnel line. A start point of a round is positioned on the tunnel line and a length of the round is provided. Further, an end point of the round is positioned at a distance corresponding with the length of the round from the start point and a coordinate system of the drilling pattern is directed such that one of its axes points from the start point to the end point. Finally, different coordinate systems are transformed.

Abstract: The surface of rock or soil, newly-exposed, for example, by tunnelling, and having the tendency to become friable on exposure to the atmosphere, can be protected by forming thereon a film by the process of combining on the surface at least one coagulable material and a coagulating agent therefor. The preferred coagulable material is an aqueous polymer dispersion, preferably one which has some degree of elastomeric properties, and preferably one which additionally is anionically stabilized.

Abstract: The present invention provides a door arrangement for a tunneling machine. The door arrangement is for location at the front of the tunneling machine adjacent to the digging end of the machine. The door arrangement allows for the interior of the machine to be sealed off from the tunnel face, while also allowing for the door arrangement to be opened and allow complete access to the tunnel face. The door arrangement comprises door sections for hinged connection to a tunneling machine, the door sections being pivotable about the hinged connection between a closed position sealing the tunneling machine and an open position allowing the tunneling machine access to a tunnel face.

Abstract: A tunnel boring machine (90) having a rotating cutter head (93) that rotatably supports a plurality of cutter assemblies (10). A plurality of instrument packages (50) are attached to the rotating cutter head, each instrument package having a distal end in contact with an associated cutter assembly. The instrument packages include a plurality of sensors including an accelerometer (32), magnetometer (33) and temperature sensor (34), for monitoring the associated cutter assembly. The sensors are mounted in a distal end of the instrument packages that is biased to remain in contact with the cutter assembly. The instrument packages include a wireless transmitter, and they are interconnected in a mesh or peer to peer network. A power supply (176) such as a battery pack is provided for each instrument package. The data from the sensors may be used to control operation of the tunnel boring machine and/or to monitor the condition of the cutter assemblies.

Abstract: A fastening element has a drilling head (21) provided at one end (16) of anchor tube (12) and having at least one inlet opening (23) that opens toward the receiving chamber (13) of the anchor tube (12), and at least one through-opening (24) that opens outwardly for passing of the hardenable mass therethrough, and a mixing element (31) for the hardenable mass and which is located in the drilling head (21) between the at least one inlet opening (23) and the at least one through-opening (24).

Abstract: An enhanced reaming apparatus and method are disclosed. A reaming assembly may have a motor and a pump that provide linear force, torsional force, and pressurized drilling fluid to a reamer to cause the reamer to enlarge the bore of a pilot hole. The reamer may have a body and a plurality of blade assemblies that cooperate to define two substantially symmetrical, oppositely oriented reaming sections. Each blade assembly may have an inner blade attached to the body and an outer blade extending outward from the body. Hard cutting elements may be used in place of the outer blade. The blade assemblies may be field-replaced, or the orientation of the reamer may be reversed to enhance the life of the reamer. The reamer has jets and circulation openings that release the drilling fluid into the bore to facilitate penetration and remove cuttings.

Abstract: A process and plant for laying a pipe in a trench comprising placing a flattened tubular preform in the trench, the perform having a reinforcement surrounding an inner seal, the reinforcement being impregnated with a resin, and inflating the perform in the trench.

Abstract: A process of boring a tunnel using an earth-pressure balance shield boring tunnelling machine having a cutting head, an excavation chamber for soil removed by boring and conveying means for removal of said soil from the excavation chamber; wherein there is injected into a stratum being bored at the cutting head a foamed aqueous solution, characterized in that (a) the aqueous solution contains two essential components which are (i) a sulphate- or sulphonate-containing anionic susfactant, and (ii) &bgr;-naphthalene sulphonate-formaldehyde condensate; and in that (b) there is applied to the soil removed by boring in at least one of the excavation chamber and the conveyor a second aqueous solution containing essentially a high molecular weight polyethylene oxide and optionally a sulphate- or sulphonate-containing anionic surfactant. The process allows easy removal of soil from the cutting head to the excavation chamber and from the excavation chamber out of the machine.

Abstract: Control apparatus for a horizontal boring tool is described which drives a boring lance via boring rods. The tool includes an input interface for receiving actual values of controlled variables of the horizontal boring tool, and an output unit for issuing control signals for controlling the horizontal boring tool. Between the input interface and the output unit is provided a fuzzy control unit which determines the control signals for activation of the horizontal boring tool from the actual values of the controlled variables and the desired values for the controlled variables by fuzzy logic while taking into account heuristic process values. The control apparatus permits automatic operation of the horizontal boring tool with good course steering and high precision.

Abstract: A trailer for a tunnel borer follower train comprises a chassis provided with a plurality of wheels, the chassis at rest presenting a longitudinal axis and a longitudinal plane of symmetry that is vertical. The trailer also comprises at least two tanks mounted on the chassis substantially symmetrically about the longitudinal plane of symmetry of the chassis; apparatus for measuring any tilt of the chassis of the trailer about its longitudinal axis; apparatus for feeding both tanks with liquid; and apparatus for controlling the quantity of liquid in each of the tanks as a function of any measured tilt in such a manner that the quantity of liquid contained in each tank creates a return torque about the longitudinal axis tending to compensate for any tilt of the trailer.

Abstract: A tunnel excavating machine having an excavating machine body can be moved forward by shield jacks. A rotatable cutter head is mounted in a front portion of the excavating machine body. An erector device for assembling segments in a ring form is mounted in a rear portion of the excavating machine body. A rest extends rearward from the rear portion of the excavating machine body. A shape retainer for making pressurized contact with inner peripheral surfaces of the assembled segments to retain the segments in a predetermined shape is supported on the rest so as to be movable along a fore-and-aft direction. Also, a revolving frame is located between the erector device and the shape retainer, and supported on the rest so as to be movable along the fore-and-aft direction such that the revolving frame does not interfere with the erector device and the shape retainer. A cage is supported on the revolving frame so as to be revolvable in a circumferential direction of an existing tunnel.

Abstract: A tunnel excavating machine of high-speed construction capable of completely stopping invasion of water and allowing covering members to be assembled easily is provided. This tunnel excavating machine comprises: a cylindrical excavating machine main portion 1 provided with a cutter head 4 and fit to an external periphery of an existing segment S through a tail seal 23; a cylindrical excavating machine auxiliary portion 2 fit to the inside of the excavating machine main portion 1 movably in the back and forth directions and provided with an erector 25 for assembling the segments; a plurality of main propulsion jacks 22 disposed between the main portion 1 and the auxiliary portion 2; and a plurality of auxiliary propulsion jacks 22 mounted on the auxiliary portion 2 and capable of being retracted with respect to the segment S.

Abstract: A cutter head is rotationally drivably mounted on a front portion of a tunnel excavating machine body, a plurality of cutter spokes are provided radially on the cutter head, a plurality of mounting holes are formed in a front surface portion of each of the cutter spokes, a valve plate is turnably mounted and has through-holes formed in correspondence with the mounting holes, relay bits are mounted movably to the through-holes and the mounting holes and rearwardly withdrawably, the relay bit can be fixed by bolts at a position at which the relay bit protrudes from the front surface portion of the cutter spoke, and when the relay bit is withdrawn rearward from the mounting hole, the valve plate is turned to close the mounting hole, whereafter the relay bit is detached and can be replaced.

Abstract: A construction method for widening road, superhighway or railway tunnels, without interrupting the traffic flow includes a first stage of excavation; in steps, of the ground between the theoretical profile of the future widened tunnel and that of the original tunnel, after having reinforced the ground between the theoretical profile of the future widened tunnel and that of the original tunnel by reinforcement operations on the face, and a second stage in which the final lining, comprising one or more arches of prefabricated segments is placed close to the face.

Abstract: A wall is built in the ground by pulling a wall building device having cross-sectional dimensions which are substantially equal to the dimensions of at least a part of the cross-section of the wall through the ground, at least a part of the wall being formed by injecting a hardenable material behind the wall building device. A tunnel is made by first making a tunnel wall, leaving the ground inside the tunnel wall substantially intact, followed by excavating the ground inside the tunnel wall.

Abstract: It is an object of the present invention to provide a tunnel excavating machine of high-speed construction type and an excavation method which is capable of stopping invasion of water completely and allows covering members to be assembled easily.

Abstract: Cutter spokes are disposed on a cutterhead of a tunnel-excavating machine. Movable blocks, each having a roller cutter, are movably supported by each of the cutter spokes while being connected one another by means of a connection link. A gate mechanism is attached to an end portion of each of the cutter spokes. A machine body is equipped with a roller cutter accommodation box such that through rotation of the cutterhead to a predetermined angular position, the roller cutter accommodation box can be selectively and removably engaged with the end portion of any one of the cutter spokes via the gate mechanism.

Abstract: An excavating device configured to form a channel of predetermined cross section in the ground in an excavation direction. The excavating device includes an assembly of jet excavating units which together define the cross section of the channel and are each provided with at least one jet device. The excavating device also includes at least one sensor which is connected to at least one of the jet excavating units for measuring a force which is exerted on the jet excavating units by the ground substantially parallel to the excavation direction. A controller is provided for controlling the excavation by the excavating device on the basis of the force measured by the at least one sensor. The controller is adapted to set a flow rate of jet liquid which is used in at least one jet device.

Abstract: A tunnel excavator includes a pair of cutters arranged side by side at a front portion of a tunnel excavator main body. These cutters rotate in opposite directions for excavating the earth to form excavation and for causing the excavated earth to move toward a center area between the pair of cutters. The tunnel excavator further includes a screw cutter extending horizontally in a width direction of the tunnel excavator behind the pair of cutters at a lower level. The screw cutter has a pair of flights spiraling in opposite directions toward the center from opposite ends of the screw cutter for gathering the excavated earth to the center of the screw cutter. A soil plate generally extends along and behind the screw cutter and pushes the excavated earth as the tunnel excavator advances, but the soil plate has an outlet at a lower center area thereof for allowing the excavated earth to pass therethrough. A conveyor is provided behind the soil plate outlet.

Abstract: A method of boring a tunnel with a tunnel boring machine comprising injecting into the formation to be bored just before the cutting tools of the boring machine and optionally into the internal discharge chamber of the boring machine, an aqueous foam containing at least one clay, at least one surfactant and at least one gas in proportion to produce a good quality, stable foam with the formation material and discharging the material from the tunnel via the discharge of the boring machine.

Abstract: A reclamation pipe boring apparatus for sewerage wherein a vehicle body (14) is provided with an outrigger (20) upwardly projecting via the center thereof and actuated by hydraulic pressure, a cutting device (25) disposed in the front region of the vehicle body (14), actuated by hydraulic pressure and having a rotary cutter (24) at the front end, lift means (30) actuated by hydraulic pressure to move the cutting device (25) up and down, reach means (35) actuated by hydraulic pressure to move the cutting device (25) back and forth, and swing means (40) actuated by hydraulic pressure to turn the cutting device (25) clockwise and counterclockwise.

Abstract: A tunnel boring machine for collecting earth excavated upon rotation of a cutter disk includes a non-pressurized chamber behind the cutter disk for collecting earth excavated by the cutter disk and discharging the earth with a carrying fluid. The machine includes a first open tank arranged in the non-pressurized chamber which serves as a vessel for containing the carrying fluid as well as a hopper for collecting excavated earth. Carrying fluid supply apparatus is provided for supplying the carrying fluid to the first open tank and suction/discharge apparatus is provided for sucking and discharging the carrying fluid supply to the first open tank rearwardly together with the collected earth. Water level control apparatus provided for monitoring a water level of a carrying fluid in the first open tank and keeping the water level between a minimum water level and a maximum water level.

Abstract: The present invention relates to a tail structure of a shield driving machine, and in particular relates to an improvement technique of the tail sealing portion of this type of shield driving machine, in order to eliminate wearing of the tail seal. The tail structure has a first tail seal 12 and a second tail seal 14. The first tail seal 12 is provided with a tail ring 12a, a seal tube 12b and packing 12c, and the tail ring 12a is secured movably in the axial direction of a skin plate 10. The packing 12c is pressure-fitted to segments 11 in line with enlargement of the seal tube 12b and is spaced from the segments 11 in line with reduction of the seal tube 12b. The second tail seal 14 is provided with a seal tube 14a and packing 14b, wherein the packing 14b is pressure-fitted to the segments 11 in line with enlargement of the seal tube 14a and is spaced from the segments 11 in line with reduction of the seal tube 14b.

Abstract: To construct a tunnel in a formation (11, 15) with zones of high hydraulic pressure (15), a gallery (13) is driven from the stable formation (11) toward the problem formation zone (15). At least one lock zone (19) with pressure-tight gates (23, 23') is constructed under protection of the stable formation (11) at some distance from the problem formation zone (15). Behind this lock zone (19) the gallery (13) is now filled with water (25) and pressurized. Further driving into the problem formation zone (15) and therethrough is now performed under water (25) having a pressure corresponding to the hydraulic pressure of the problem formation zone (15). For this purpose the machines (47, 47', 73) are remote-controlled and are controlled and monitored from the atmospheric zone (17). Material transportation operations are managed substantially via the lock zone (19).

Abstract: The present invention relates to a shield driving machine by which eliminates excessive work of the ground when working at a curved section while suppressing an increase of the sinking of the ground surface and securing a quickening in the stability of segments. In the shield driving machine, a bulkhead 16 is provided at the tip end side of the shield driving machine body 14 of the shield driving machine 10. The chamber 18 which is formed by the bulkhead 16 and has the tip end side open is filled up with excavated earth and sand and is used to oppose the earth pressure and water pressure in the natural ground. A rotating shaft 22 which supports cross-shaped spokes 20 penetrates on the center axis of the bulkhead 16. At the shield driving machine 10, a plurality of openings 24 which discharge a part of the excavated earth and sand supplied from the chamber 18 to the rear side of the shield driving machine body 14 are provided at the hood portion 27.

Abstract: A tunneling machine intended to stably carry out gripper replacement by restricting the load imposed on gripper jacks for the main gripper as much as possible during excavation of an inclined shaft. Such a tunneling machine comprises (1) a main beam that extends along a tunnel wall, (2) a nose gripper disposed in front of the main beam for gripping the main beam against the wall of a pilot shaft and a main gripper disposed behind the main beam for gripping the main beam against the wall of a reamed shaft, (3) a main frame supported by the main beam so as to be slidable back and forth and supporting a cutter head at the front portion thereof, (4) a holding gripper (composed of a roof support, side support, vertical support) for gripping the main frame against the wall of the reamed shaft, (5) thrust jacks coupling the main frame to gripper shoes for the main gripper, and (6) retaining jacks coupling the main frame to a carrier.

Abstract: A bulkhead for manufacturing underground structures such as earth cavities in a closed construction method, formed of sealing walls arranged as an enclosure and sealing earth masses to be removed against ground water, wherein the sealing walls are formed of a hardened mixture of bentonite-cement injected under pressure into the ground, characterized in that the sealing walls inserted into fine sand or silts are arranged in the form of a roof and are formed as a substantially elastically deformable bulkhead envelope by adding filler to the mixture of bentonite-cement. Preferably, the bulkhead sealing walls of the bulkhead envelope extend from a central ridge line on the earth surface or below it downwardly in an obliquely diverging direction into water-impermeable soil. The bulkhead can be made airtight so that a vacuum can be applied to the earth mass enclosed by the bulkhead envelope.

Abstract: An earth discharge control system for a small-diameter pipe propelling machine controls the excavated earth discharging operation of the small-diameter pipe propelling machine. The small-pipe propelling machine propels a small-diameter pipe (2) joined at its leading end to a leading pipe (1) into the ground by a propelling unit (3) installed in a starting shaft (4). Earth excavated by a cutting head (8) supported on the leading end of the leading pipe (1) is conveyed toward the starting shaft (4) by a screw conveyor (6) disposed within the small-diameter pipe (1). A pneumatically operated control valve (10) is disposed in combination with a portion of the screw conveyor (6) within the leading pipe (1).