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 works 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 ultrasonic wave transmitting and receiving devices disposed as spaced at least along a radial line on the front surface of a substantially disk shaped rotary cutter head of the machine for transmitting ultrasonic waves in forward and upward directions and receiving reflected waves from tunnel face ground wall, a wave transmission and reception controlling means, and a transmission-to-reception time interval detecting means for determining distances from the respective wave transmitting and receiving devices to the ground wall.

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: An improved attitude control system for tunnel boring machine shields is provided. A laser beam transmitter is installed in an already bored tunnel behind the machine shield for transmitting a laser beam in parallel to a predetermined tunneling direction and a device for receiving the beam is installed in the shield for detecting any deviation of the shield from the beam so that, when the deviation is detected during tunneling work performed by rotating a foreward end cutter head of the shield and propelling the shield toward tunnel face ground with a plurality of jacks installed at rearward end of the shield, the jacks are selectively driven in response to resultant deviational direction and amount of the detection so as to remove the deviation.

Abstract: A device for removing relatively larger size gravels, stones, crushed rocks and the like contained in a discharged mixture of fed slurry or muddy water and excavated ground formation components in hydraulic tunnel boring systems. The device comprises a lattice-shaped classifying means connected at one end to a discharging pipe for conducting the mixture from the tunnel face, a primary chamber connected to the other end of the classifying means for receiving and storing classified gravels and the like, and a secondary chamber communicating with the primary chamber through a valve for receiving and retaining the gravels and the like filled in the primary chamber. A housing surrounds and rotatably supports the classifying means and includes a discharging pipe for conducting muddy water passed through the clarifying means. A motor rotates the classifying means for performing classifying work.

Abstract: Attitude controlling method of tunneling machine shield and system for performing the method, wherein a plurality of jacks installed at a tail end of the shield for propelling the same toward tunnel face ground are selectively driven when the shield deviates from intended tunneling direction. Such deviation detected is first indicated in an indicating and controlling unit and then the unit is operated to actuate an associated circuit connected to the respective jacks in accordance with the indicated deviation so that selective ones only of the jacks effective to correct the deviation will be driven.

Abstract: A tunnel driving and forming method with hydraulic boring machine through mixed ground of stable and unstable layers which is simplified in equipments, less in air contamination and noises and high in working accuracy. The method comprises steps of driving the hydraulic boring machine into the ground to bore a tunnel therein, installing segments sequentially against bored tunnel wall right behind the machine as the same advances, impregnating a back-filling agent between said bored tunnel wall and outer periphery of installed segments, removing the rearmost set of a certain number of sets of said installed segments behind the machine for circulatory use as long as the ground bored is stable, reinforcing exposed surface of said back-filling agent impregnated and set, and repeating respective said steps responsive to advances of the machine.

Abstract: A method of completing a tunnel excavation with a slurry shield type tunneling machine through a soft ground having a high water content or much gushing water, advancing the machine from the ground into a vertical shaft at, for example, a tunnel terminating point while preventing any ground collapse or gushing water at a vertical shaft wall finally excavated, and an apparatus for performing the method.

Abstract: A method of and apparatus for starting a tunneling operation into a soft ground having a high water content or much gushing water while preventing any collapse of the ground or outflow of water. The tunneling machine is initially placed within a vertical shaft in the ground and a sheet pile is struck into the ground between a retaining wall of the shaft having a starting port through which the machine is to be ultimately advanced into the surrounding ground after the port is opened by raising the pile. A ring-shaped liquid-tight packing is applied to the retaining wall and surrounding the starting port engages the periphery of the head portion of the tunneling machine to form part of a liquid-pressurized chamber in front of the machine, the pressure in the chamber being at least as high as the surrounding underground water or ground pressure when the port is opened and the machine is then started through the port.