Abstract: A shield excavator excavates a shaft. Then, the excavator is caused to swing to change its posture and excavate a tunnel. Thus, the shaft and the tunnel is continuously excavated by the single machine.

Abstract: A bracing device for a self-advancing shield tunnelling machine for tunnel construction comprising a control shield within which is mounted a cutting unit, and at least two bracing shields each having a closed circumferential wall construction which are connected together by feed cylinders, the bracing shields being able to be radially braced with the tunnel wall independently of each other by bracing elements fixed thereon. The bracing elements are composed of elastic pressure hoses positioned around the closed circumferential bracing shield walls. The circumferences of the bracing elements can be continually enlarged by expansion, particularly by inflation. The invention furthermore relates to the use of such bracing elements for a self-advancing shield tunnelling machine in which the control shield and the first bracing shield arranged behind it as well as the first and second bracing shield engage in each other and overlap telescopically.

Abstract: An underground excavator includes a chamber defined in the forward section of an excavator body for receiving excavated material such as soil, sand, gravel, clay and their mixtures. A rotary cutter is mounted to the forward end of a rotary shaft for penetrating through the chamber for axial rotation and simultaneous rocking in an axial direction. The cutter has a conical cutter face plate having holes for passing the excavated material of a diameter smaller than an opening disposed in the chamber. Any gravel or the like present in the advancing route to the underground excavator and smaller than the holes of the cutter is received into the chamber to be discharged from the excavator. Any gravel larger than the holes or the like not receivable into the chamber is moved quickly along the conical cutter face plate toward peripheral ground layer by being subjected to the rocking motion of the conical cutter face plate simultaneously with the rotation of the cutter during advancement of the excavator.

Abstract: Directional control of a shield excavator is automatically carried out merely by inputting a direction of rotational moment to which the excavator is directed and a magnitude of the moment.

Abstract: Disclosed is a continuous tunneling and lining machine. The machine is capable of simultaneously boring and lining a tunnel through a solid medium. The machine comprises four major components including: (1) an excavation system; (2) a debris removal system; (3) a lining system; and (4) a liner material retrieval system. The excavation system comprises a rotary excavator that excavates the tunnel bore. The lining system mixes liner materials at the bulkhead and pumps the mixed material into slipform. The slipform comprises an inner form, an outer form and a wall connecting the inner and outer form and at least one mandrel. The mandrels form cast in place passageways to accommodate liner component retrieval and excavation debris removal. The debris removal system pumps excavation debris through the excavated area into the mandrels and out the cast in place passageways.

Abstract: Method of controlling the trajectory of a shield-type tunnelling machine equipped with displacement control hydraulic rams (3), characterized in that, these rams being divided into at least three groups of rams (6A, 6B, 6C), the theoretical instantaneous flowrates of fluid to be applied to each of these groups are continuously determined (40) from the curvature characteristics and the overall rate of advance set point trajectory and these groups (7-26-27-28) are supplied with instantaneous flowrates, the values of which correspond to the theoretical values.

Abstract: The invention relates to an apparatus for underground tunneling. It has a working tube which can be driven in the drilling direction and a digging unit mounted therein, and it has a cutterhead which can be shifted back and forth and radially of the axis of the apparatus. When the cutterhead is not deflected radially, the entire digging unit has a substantially smaller cross section than corresponds to the internal cross section of the working tube. A scoop disposed on the floor of the working tube and provided with a shovel-like mouth at its front end serves for the simple and cost-effective removal of the earth loosened by the cutterhead. The scoop is at first urged forward out of the working tube by means of a drive mechanism in order to shovel up loosened earth, and then it is withdrawn rearwardly out of the working tube, emptied, and run back again into the working tube.

Abstract: A shield tunneling machine comprises a shield body, a rotor disposed in a front portion of the shield body, support is provided behind the rotor in the shield body and for supporting the rotor to be eccentrically movable around the center axis of the shield body, drive motor for moving the rotor eccentrically and a seal disposed between the support and the rotor. The seal is provided with an annular recess provided around the center axis in a portion where one of the supports and the rotor faces the other and opened to the other of the supports and the rotor, a ring disposed in the recess to be movable in the direction of the center axis and having a generally constant outer diameter and a spring for pressing the ring toward the other of the supports and the rotor. The diameter D.sub.1 of the ring, the maximum diameter D.sub.2 of the contact portion between the ring and the other of the supports and the rotor and the eccentrically e of the eccentric movement have the following relationship; D.sub.1 .ltoreq.D.

Abstract: A method for renewing an existing pipeline comprises the steps of advancing a shield tunnelling machine from one end of an existing pipe defining the existing pipeline to the other end thereof, excavating at least the existing pipe by the machine and disposing a new pipe in an excavated spot while the machine is advanced, whereby the existing pipeline is renewed by breaking the existing pipe embedded in the ground while laying the new pipe therein. An existing pipeline renewing apparatus embodying the method described above comprises a shield tunnelling machine for excavating an existing pipe embedded in the ground so as to define an existing pipeline and a means for disposing a new pipe in a spot excavated by the machine. Accordingly, since the new pipe is disposed while excavating the existing pipe by the shield tunnelling machine, it is not necessary to excavate the spot, in which the existing pipe to be renewed is laid, by an open cut method.

Abstract: A method for lining a tunnel wall formed by a shield excavation includes filling a space between the tunnel wall surface and the outer peripheral surface of a lining form in two stages by dividing space into two, portions. One stage of the method is carried out with a ring-shaped rearward end frame ring secured to excavator propelling jacks and disposed to define a first space portion and a second stage of the method is carried out accompanying forward propulsion of the excavator.

Abstract: A form for a concrete tunnel lining usable behind a tunnel excavator with a traveling shield is made of an inner tunnel-lining sheathing and a form front. The inner tunnel-lining sheathing is divided into a plurality of sheathing segments or rings movable independently of each other with intervening segment-bridging yieldable joints. The form front located between the traveling shield and the inner tunnel-lining sheathing is movable forwardly by the conrete which presses in the annular space formed by the traveling shield and/or the surrounding earth and by the inner tunnel-lining sheathing as well as the form front. An operationally beneficial design results when the inner tunnel-lining sheathing is set up for forward motion of the sheathing segments in the tunnel longitudinal direction singly or in groups one after the other relative to the remaining sheathing segments held or remaining at rest.

Abstract: A process for lining a tunnel with concrete behind a tunnel excavator having a for front advanced along with an excavator head in which the concrete is forced between the surrounding subterranean geological structure and an inner tunnel-lining form through a form front which rides sealingly on the outer surface of the inner tunnel-lining form and on the inner surface of the shield. Simultaneously, the form front, which is longitudinally movable relative to the shield, moves forward relative to the inner tunnel-lining form. The form front is movable forward simultaneously balancing the friction forces occurring between the form front and the shield and the inner tunnel-lining form. Satisfactory results are obtained when the friction forces between concrete sections of a predetermined length are measured by moving the form front relative to the stationary shield and the inner tunnel-lining form during an interruption in concrete feed.

Abstract: The earth pressure shield for a tunnel and/or gallery excavator has a front working compartment formed by a separating wall having a digging tool and an annular reinforcing space substantially triangular in cross section positioned directly in front of the separating wall. So that an extensive restructuring of the machine is not necessary when moving from soft earth to hard ground, the annular reinforcing space is provided with a lower fluid feeder, a controlled upper pressurized air feeder, a plurality of fluid conductor pipes which are guided from below to an upper fluid outlet opening into the working compartment, and a fluid level controller. The invention is based on the consideration that a reliable and satisfactory support of the local front wall is only possible when the local front wall in the vicinity of the roof can be supplied with a fluid.

Abstract: An excavated earth and sand transporting apparatus for use in a shield machine for carrying the earth and sand excavated by a cutter head mounted on the most front part of a shield proper through a screw conveyor followed by a transporting pipe to rearward of the shield proper. The excavated earth and sand transporting apparatus has an excavation discharging device mounted between the screw conveyor and the transporting pipe to discharge the earth and sand or the excavation conveyed by the screw conveyor into the transporting pipe while keeping a predetermined earth pressure inside the cutter head chamber so that the spouting of spring water can be prevented without having to use a bentonite slurry and/or a clay slurry and that the excavated earth and sand or excavation can be discharged efficiently and effectively.

Abstract: Method and device for driving a tunnel by means of a tunneling machine (10). At the same time as the tunnel is driven, an injection hole (91) is drilled in front of the tunnel front (90) by a rock drilling machine (53) placed behind the tunneling machine.

Abstract: A tunnel excavator has a substantially tubular shield having rotatably mounted on one end a motor-driven cutting disk rotatably carrying a multiplicity of roller cutters. The shield is comprised of a head section having front anchors in addition to the cutting disk, an inner section telescopically nested in the head section and constrained to only axial displacement relative to the same, and a tail section having rear anchors and coupled to the inner section for both bending and rolling movements relative to the same. Hydraulic push jacks act between the head and tail shield sections for advancing the shield. A pair of hydraulically independent antirolling jacks are connected between the inner and tail shield sections so as to enable the tail shield section, which is anchored during excavation, to bear against the rolling of the head shield section.

Abstract: Disclosed is a continuous tunneling and lining machine. The machine is capable of simultaneously boring and lining a tunnel through a solid medium. The machine comprises four major components including: (1) an excavation system; (2) a debris removal system; (3) a lining system; and (4) a liner material retrieval system. The excavation system comprises a rotary excavator that excavates the tunnel bore. The lining system mixes liner materials at the bulkhead and pumps the mixed material into slipform. The slipform comprises an inner form, an outer form and a wall connecting the inner and outer form and at least one mandrel. The mandrels form cast in place passageways to accommodate liner component retrieval and excavation debris removal. The debris removal system pumps excavation debris through the excavated area into the mandrels and out the cast in place passageways.

Abstract: A tunnel wall lining method is provided, wherein annular recesses circumferentially are provided in outer periphery of a lining form into which arcuate segments are assembled, a plurality of rows of reinforcing bars are arranged annularly in the respective recesses of the lining form, and a lining is constructed with concrete cast into a space between the tunnel wall and the lining form. The lining thus constructed includes circumferentially extending and radially inwardly projecting beams in which the reinforcing bars are embedded, whereby a lining having a reinforcing structure can be constructed in a simple and economical manner and in a shortened construction period.

Abstract: A shield-type tunneling machine comprises a shield body having a front portion converging gradually rearward, a crankshaft journalled rotatably by a diaphragm provided in the shield body, a drive mechanism connected to an end of the crankshaft and a conical or frustoconical rotary head supported rotatably by the other end and disposed in the front portion of the shield body to be turned eccentrically, a gear mechanism for forcibly rotate the rotary head and a means for discharging debris from a front area of the diaphragm to a rear area. The tunneling machine, when thrusted in the ground by a jack, receives earth and sand into the front portion of the shield body and compresses them between the rotary head and the shield body to send them to the rear. The machine can be used for a pipe jacking as well as the tunneling in the soft ground.

Abstract: This invention provides an apparatus for construction of an underground or aboveground continuous article (98) which has at least one bore (99). In case the article is made underground, the apparatus has at least one rotary cutter (51) for excavating the earth and a spoil discharge device which separates water from the spoil (97) and discharges separately the water and the dewatered spoil, respectively. The apparatus has at least one electric heater (49) for heating material (95) passing a space (67) disposed between a tubular member (45) and a bore forming member (46).

Abstract: A tunneling machine with a leading ring, a follower ring, an overlapping joint connection between the leading ring and the follower ring, a pressure ring, advancing piston/cylinder assemblies, and a roll correction device. The advancing piston/cylinder assemblies are distributed about the shield circumference, and they are connected on the one hand by the way of linkages to the pressure ring, and on the other hand they are supported at the leading or shield ring. The roll correction device has a roll correction ring which is arranged in the leading ring, and the roll correction ring can rotate with respect to the leading shield. The roll correction ring is also supported by a thrust-absorbing bearing. The advancing piston/cylinder assemblies are movably joined at the roll correction ring, and are indirectly supported at the leading ring.

Abstract: A tunneling machine of the type having a leading shield, a trailing shield, an annular form connected to the trailing shield by respective cylinder units for the emplacement of the concrete behind the machine and cylinder units for relatively advancing the leading and trailing shields, is also equipped with a telescoping shield assembly with its own set of cylinder units so that the concrete emplacement can be decoupled from the advance of the cutting head on the leading shield.

Abstract: Method for thrusting a shield for use in tunneling includes the steps of causing a rotary head, provided at the front portion of a shield body, an eccentric motion so that earth, soil or sand covering the front of the shield is pressed away radially of the shield, and exerting a thrust on the shield body during the eccentric motion of said rotary head. Apparatus for carrying out the method includes a driven crank shaft or a driven eccentric straight shaft, a conical or frustoconical rotary head supported rotatably by the crank or eccentric straight shaft, conveyor for discharging mined material backwardly, and hydraulic jacks for imparting a thrust to the shield body.

Abstract: One construction method for burying offshore pipelines utilizes a segmented excavation shield for forming a trench in the seafloor. The present invention provides a propulsion method for advancing the shield which eliminates the need to pull the shield. This is done by advancing skin plates which are attached to the shield, then advancing the shield by transmitting soil reaction through the skin plates, which remain stationary, to the shield.

Abstract: A driving process for enlarging a tunnel wherein a primary shield machine is driven along an ordinary diametrical tunnel to a predetermined region to be enlarged. An enlarged starting base is formed in the rear of the primary shield machine. An enlarging shield machine is assembled in the enlarged base. Thereafter, the primary shield machine and the enlarging shield machine are both driven forward along the predetermined region of enlargement to construct an enlarged tunnel.

Abstract: A shield machine for enlarging a portion of an existing tunnel includes an inner and outer double cylinder shaped shield machine body with a cylindrical outer shield portion and a cylindrical inner guide portion designed to be driven in an axial direction of an existing tunnel and along an outer circumferential surface of primary assembly segments lining the existing tunnel. Jack members are provided for pushing forward the shield machine body by receiving a reaction from a reaction member such as secondary assembly segments lining a constructed enlarged tunnel. A scraper member is positioned adjacent to the inner guide portion for removing a back-filling agent on the outer surface of the primary assembly segments.

Abstract: An excavating and propelling machine for laying pipelines underground has a plum-pudding stone crusher device comprising a plurality of rod-shaped rotary teeth formed integrally on the rear face of a disk-shaped rotating cutter head in a manner of extending radially at uniform intervals spaced apart from one another and a plurality of rod-shaped stator teeth formed integrally on the front surface of an annular front face plate in a manner of extending radially at uniform intervals space apart from one another. The rotary teeth and the stator teeth are disposed in the vicinity of each other.

Abstract: A tunnel boring machine for boring a tunnel through mixed ground with stable ground conditions and unstable ground conditions. The tunnel boring machine is operable in a stable ground boring mode with the machine anchored to tunnel sidewall portions and also in an unstable ground mode wherein cutting thrust is provided by a shield means in cooperation with tunnel lining structure. Combined mode operation is also possible.

Abstract: A drive shield for tunnel driving has a plurality of cutters supported for longitudinal displacement on a frame. The cutters are hollow and contain double-acting hydraulic rams used to displace the cutters and the frame. The rams are linked to the cutters via alignable connector shackles and detachable bolts. To connect the rams to the frame use is made of coupling pieces which have spigots engaging through shackles on the rams. The coupling pieces pass through slots in the cutters and are guided on the frame for displacement to release or mate the spigots with the shackles.

Abstract: A method and apparatus for forming continuous concrete walls in tunnels or galleries is provided. More particularly, the invention relates to a form that is slidable through the gallery or tunnel. The form is an elongated supported tubular structure generally conforming to the shape of the gallery or tunnel. The outermost surface of the form is spaced from the wall of the gallery or tunnel a sufficient distance to enable an appropriate amount of concrete to be poured or pressed therein. The form is adapted to have the concrete pumped into the annular spaced provided for it, and to have the force of the concrete against the leading edge of the form cause the form to slidably advance through the gallery or tunnel.

Abstract: A tunnel knife shield has a support frame, and a plurality of knives positioned side-by-side on the support frame. Each of the knives is associated with a double-acting hydraulic ram, the rams being used for advancing the knives, and for causing the support frame to follow up the advance of the knives. Hydraulic control means are provided for controlling the extension and retraction of the rams. Each ram has first and second working chambers, pressurization of which is effective to extend and retract that ram. The hydraulic control means comprises respective first supply lines for supplying pressurized hydraulic fluid to the first working chambers, respective second supply lines for supplying pressurized hydraulic fluid to the second working chambers, and respective discharge lines for discharging hydraulic fluid from the first working chambers. Each discharge line is provided with a flow-regulation valve and a pilot-operated non-return valve.

Abstract: A soil transporting vehicle for pressurized receiving and transporting of soil excavated by a shield machine. The vehicle includes a cylindrical soil container having a first opening and a second opening aligned along the longitudinal axis and being pressure-resistant. A soil conveying mechanism is arranged in the container adjacent to the opening for moving the soil axially. A chassis rotatably supports the container and a drive mechanism is provided for rotating the container about its axis from a soil introduction position where the openings are directed upwardly and a soil discharge position where the openings are directed downwardly. An inlet for introducing gas under pressure and a pressure regulating valve are provided on the soil container. The pressure is regulated to be substantially equal to that of the pressure compartment of the shield machine. A compressor is connected with the gas inlet.

Abstract: Tunnel driving apparatus incorporates a cutter shield with a plurality of drive members or cutters arranged side-by-side in a cylindrical array. The drive members are supported and guided for individual longitudinal displacement on a cylindrical continuous cowl or casing forming at least part of a support frame. Rams which serve to shift the drive members and the frame are coupled therebetween and extend through sealed openings in an end wall of a recess formed on the exterior of the cowl and open towards the drive members.To facilitate the creation of a concrete lining for the tunnel behind the cutter shield, a rear shield is formed by reduced rearwardly extending tails of the drive members. A further cylindrical casing locates within the rear shield and supports a pair of annular rings. One of these rings combines with a sheathing extending inside the further casing and the rear shield to form a concrete reception space.

Abstract: A hydraulic control system serves to control the operation of hydraulic rams used to position and displace an annular member which delimits a concrete reception space disposed at the rear of a tunnel-driving apparatus. The system acts to compensate for irregular loading on the annular member to ensure the latter is drawn up behind a forward drive shield without twisting or tilting. The rams are divided into groups each connectible to its own pump unit and the system connects the chambers of the rams which reduce in volume as the member is drawn up to the pump units in a manner such that the latter act as brake motors to restrain the member against the concrete pressure differential on its rear side.

Abstract: An excavation controlling method for hydraulic shield tunnelling wherein decisions are made during advances of tunnel excavation on whether respective excavated soil amounts per macroscopic unit distance belong to the same statistic population and, with respect to excavated amounts per microscopic unit distance divided out of the macroscopic unit distance, whether excavated amounts per microscopic unit distance of the same dividing order belong to the same statistic population.

Abstract: Apparatus for use in driving tunnels or the like has a main shield composed of elongate drive members supported and guided on a rigid frame as known per se. Rams serve to advance the drive members and the frame in alternative to effect the driving operation. A rear shield or cover is located behind the main shield. This rear shield is composed of elongate rear extension members connected with some of the drive members over the roof and part of the side walls of the tunnel. Supports fixed to the rear of the frame of the main shield engage beneath the lowermost rear extension members to support the rear shield. The supports, disposed symmetrically at either side of the axis of the tunnel, have brackets engaging with the lowermost rear extension members and these brackets can be displaced by piston and cylinder units to raise or lower the entire rear shield.

Abstract: A method and an apparatus for constructing an underground structure by having a plurality of serially adjoining cylindrical bodies propelled underground one after another either in one direction or from opposite directions. A thrusting/pulling jack advancing arrangement, thrusting jack and pulling jack advancing arrangements, connecting and traction members, fixing pieces and fasteners are used in combination to propel each cylindrical body one by one by virtue of a sum total of reaction forces developed at other cylindrical bodies and some additional reaction facility, if necessary.

Abstract: A tunnel drive shield has an arcuate support frame constituted by a pair of foot segments, a pair of wall segments supported by the foot segments and a ridge segment connecting the tops of the wall segments. The foot segments engage the tunnel floor, and the wall segments are braceable outwardly towards the tunnel walls. Each foot segment is provided with a pair of longitudinal floor skids displaceably mounted on the base thereof. Each foot segment is also provided with a pair of longitudinally-spaced, vertically-movable support feet, which are movable into contact with the tunnel floor to relieve, at least partially, the load on the floor skids. The support feet are used to support the shield while the floor skids are removed. The rest of the shield can then be dismantled within the confines of the tunnel.

Abstract: A method and an apparatus for advancing cylindrical bodies. More than two underground cylindrical bodies are laid in longitudinal alignment with thrusting jacks disposed between them. A connecting member is arranged to pierce through them. A fastener is attached to one end of the connecting member while an advancing jack arrangement which has a removable-and-attachable fastener is attached to the other end of the connecting member. A suitable anchor body is disposed in front of the alignment of cylindrical bodies. Between the anchor body and each of the cylindrical bodies, there is provided a fixing member which pierces through them. Removable-and-attachable fasteners are disposed between the fixing member and the cylindrical bodies to interlink them for moving them forward underground one after another.

Abstract: A method of horizontally and vertically guiding a cutter advance mechanism involves adjusting and fixing each individual cutter plank of a plurality of cutter planks for a radial change of direction with respect to the apparatus and by guiding the individual cutter planks in the circumferential direction during its advance. The individual planks are provided with a tip which is pivotally attached to its front portion. Wedge surfaces which may be deployed are provided in the vicinities of the front and rear ends of the planks so as to engage the support frame. Two additional wedge surfaces are provided at side surfaces of the central plank, others of the cutter planks, are provided with a further wedge surface at respective sides thereof facing away from the central plank.

Abstract: A tunnel drive shield comprises a cylindrical shell supported by two axially-spaced frames. The two frames are movable, relative to one another, in the direction of tunnel advance. In order to guide the two frames accurately, guide means interconnect the two frames, the guide means permitting movement only in the direction of tunnel advance. The guide means may be constituted by a plurality of telescopic guide devices. A knife shield may constitute the drive shield.

Abstract: A knife shield comprises a plurality of elongate knives which are arranged side-by-side upon a common support frame, the knives defining a generally cylindrical shield. Each knife is supported on the frame for movement in its longitudinal direction. At least one pair of diametrically opposed knives are coupled together, in the manner of a trackrod, for conjoint movement with respect to the longitudinal axis of the shield. During this movement the knives of the coupled pair concerned remain substantially parallel. The movement of the knives is used for controlling the direction of advance of the shield.

Abstract: The proposed shield comprises in its frame a drive for advancing the shield along a path, a device for absorbing the thrust force from the drive and transmitting it to concrete in the process of its being pressed, a forming unit for forming the inner surface of a concrete lining, which, according to the invention, includes a former mounted coaxially in the shield frame and adapted to move by a drive along the shield longitudinal axis, and a supporting structure installed rearwardly of the former and adapted to move along the longitudinal axis of the concrete lining. The present invention will be most advantageously used in sand or unstable soil, where it makes possible to drive a tunnel practically without setting the earth surface and to preserve overground buildings situated close to the tunnel construction area. The present invention prevents the concrete lining from cracking in the process of its being formed.

Abstract: In a tunnel boring or shield machine including a chamber defined between a working face and a bulkhead mounted in a machine frame of a shield machine body, means for controlling the amount of earth or muck conveyed to the exterior of the shield machine from the chamber in which earth is accumulated, and drive means for propelling the shield machine body toward and into the working face, a control method and system for ensuring stable boring operation at the working face by detecting the amount of earth or muck excavated or removed from the working face per unit time and the amount of earth or muck conveyed from the chamber per unit time, comparing these two detected values to generate an earth amount deviation signal representing the difference therebetween, controlling the amount of conveyed earth or muck and/or the amount of removed earth or muck in response to the earth amount deviation signal to maintain the earth pressure in the chamber within a predetermined range thereby ensuring stable tunnel boring o

Abstract: In a tunnel boring or shield machine, a method and system for controlling the earth pressure, in which the earth pressure in the chamber of the shield machine body is detected and the detected earth pressure is compared with a reference value to thereby produce a chamber earth pressure deviation signal. In response to the chamber earth pressure deviation signal, means for controlling the amount of conveying earth accumulated in the chamber to the exterior of the machine body and/or means for advancing the shield machine body into the working face are controlled so as to maintain the earth pressure in the chamber within a predetermined range so that the breakdown of the exposed face or earth stratum as well as the rising of the ground are prevented from occurring.In another method and system, the earth pressure at the working face is detected and the detected value is compared with a reference value to produce a signal representing the earth pressure deviation at the working face.

Abstract: Shield tunneling machine and method which may minimize the variation in water- and earth-pressure at the tunneling face so as to hold the ground firm and to ensure the safe tunneling.

Abstract: The drive members of a drive shield, which are mounted side-by-side for longitudinal displacement as is known per se, are provided with seals or packings to close off the gaps between adjacent members. Each seal or packing is composed of two flexible resilient parts joined to respective drive members. The seal parts slidably engage one another in sealing fashion. The parts of the seal may be of the same or disimilar shape but at least one of the parts is hollow with an interior cavity which can receive pressure medium used to expand the part to urge the contacting surfaces of the parts into close sealing contact. Lubrication between the contacting surfaces to permit sliding can be achieved by employing a suitable lubricating agent as, or in, the pressure medium and by allowing some of the pressure medium to pass from the interior cavity to the contacting surfaces.

Abstract: A shield type hydraulic tunnel boring machine having means for detecting an occurrence of excess excavation due to accidental collapse in tunnel face ground apt to occur during tunnel boring through soft and unstable ground and for further determining the location, shape, scale and the like of such excess excavation occurred is provided. The means comprises optimumly a plurality of rod-shaped members capable of being extended out of and retracted into the machine. Amounts by which these members are paid out until they reach ground wall of any cavity due to the occurred excess excavation are measured to determine the actual state of such cavity. The means is provided preferably at a plurality of proper positions on a shield body of the machine and respective values of the measured amounts at these positions are recorded and displayed, whereby the location, shape, scale and the like of the occurred excess excavation can be confirmed.

Abstract: Shield apparatus for tunnelling comprises a framework supporting drive members advanced individually or in groups as known per se. The framework and its drive members are carried by a pair of elongate floor beams arranged at the sides of the tunnel wall. Each floor beam has a longitudinal slot or groove therein which is open to the rear end of the beam. This slot or groove receives anchoring pins fitted in situ into the floor of the tunnel working so that the beams can slide along the pins in the direction of advancement.

Abstract: Apparatus for driving and lining tunnels utilizes a knife shield for driving a tunnel and shuttering for forming a concrete lining behind the knife shield. The shuttering is constituted by a plurality of shuttering elements, each of which is connected to, and inwardly off-set from, a respective knife. The shuttering elements are, therefore, advanced together with their knives and concrete is forced into the space between a shuttering element and the tunnel wall as that element is advanced.