JP2013108318A - Middle pushing device - Google Patents

Abstract

Provided is an intermediate pushing device that disperses a propulsion force for propulsion and embedding of an excavator and a propelling pipe row to an intermediate portion of the propelling pipe row without concentrating at the rearmost end of the propulsion pipe row.
A forward ring having a cylindrical front step portion 3 having a diameter smaller than an outer diameter of a propelling tube 12 at a front tip portion and extending a cylindrical front tube 4 having a diameter substantially the same as the outer diameter of the tube at the rear thereof. The front step portion 3 of the body 2 is inserted into the tube collar and has a cylindrical rear step portion 6 having a diameter smaller than the outer diameter of the tube, and ring-shaped flanges 8 are provided at both front and rear ends of the rear step portion 6. In the circumferential direction of the inner circumferential surface of the rear stepped portion 6, a notch is provided in a portion where a plurality of intermediate press jacks 9 are installed, and the other is provided with a concrete having substantially the same thickness as the tube wall body. A plurality of intermediate push jacks 9 are installed in the notch, and a rear step portion 6 of the rear ring 5 is formed by extending a cylindrical rear tube 7 having the same diameter as the outer diameter of the tube behind the rear flange. Was installed from the rear side of the front cylinder 4 of the front ring body 2, and the stepped portion of the pipe whose tip was smaller than the outer diameter of the propelling pipe 12 was inserted into the rear cylinder 7 of the rear ring body 5.
[Selection] Figure 1

Description

  The present invention relates to an intermediate pressing device that disperses a propulsion force for embedding an excavator and a propelling pipe row in an intermediate portion of the propelling pipe row without concentrating it on the rearmost end of the propelling pipe row in the propulsion method. The present invention relates to an intermediate pushing device that can be smoothly constructed even in the propulsion construction and the curved section.

  The propulsion method is a method in which propulsion pipes are buried in the ground while excavating the face with a tip excavator. The propulsive force for advancing the excavator and the propelling pipe row is performed by a main pushing jack installed in the starting vertical shaft, and pressurization of the main pushing jack is applied to the rear end face of the propelling pipe. The propulsive force is mainly the frictional resistance between the outer periphery of the propulsion pipe and the surrounding ground, and increases in proportion to the propulsion distance. As the propulsion extension becomes longer, the propulsive force gradually increases, and a force exceeding the axial load capacity of the propulsion pipe acts. For this reason, an intermediate pushing device that disperses the propulsive force by providing a plurality of intermediate pushing jacks in advance in the intermediate joint portion of the propelling pipe row is used.

As shown in FIG. 5 of Japanese Patent Application Laid-Open No. 2000-54786, the structure of a generally used intermediate pressing device is such that the tip portion has a small diameter within a collar fixed to the rear end of the front propulsion pipe. The tip step portion of the first propulsion pipe S having the step portion thus formed and having a long ring extending backward is inserted. On the inner periphery of the ring body, a plurality of intermediate push jacks are arranged uniformly in the circumferential direction and fixed to the inner wall of the ring body with metal fittings. Further, a second propulsion pipe T having a long stepped portion with a small diameter at the tip and having a collar into which the small diameter stepped portion of the next propulsion pipe can be inserted is inserted into the ring body and is inserted into the ring. It has a structure that comes into contact with the rear end of the intermediate push jack through a ring-shaped ring. The expansion / contraction length of the intermediate push jack has the longest stroke length, so that the pushing distance at one time becomes large and the propulsion efficiency is improved. However, if the jack stroke is lengthened, the first propulsion is carried out. The length of the ring body of the tube S is required to include the height of the jack, the stroke length, and the overlap with the second propulsion tube T. There is a problem that the length becomes long.

Further, the length of the step portion of the second propulsion pipe T coming out from the rear end of the first propulsion pipe S is equal to the length of the intermediate push jack in order to collect the intermediate push jack and the like in the ring after the propulsion is completed. It is necessary to secure a length corresponding to the height of the wheel, and a step portion of several tens of centimeters is usually generated. For this reason, at the time of normal propulsion construction, the surrounding natural ground tends to collapse, resulting in an increase in propulsive force. In particular, during the extension of the intermediate push jack, the stroke length is added and the stepped portion becomes longer, and the collapse of the surrounding natural ground becomes larger.

For this reason, an intermediate pressing device has been developed for the purpose of efficiently and effectively forming a curve even if the length of the entire intermediate pressing device is shortened. A step portion of a small diameter is formed at the front tip portion, and a step portion of the outer cylinder formed by extending a long cylindrical front ring body substantially the same diameter as the outer diameter of the propulsion tube is arranged at the rear end of the propulsion tube. An inner cylinder made up of a cylindrical intermediate ring having ring-shaped flanges at both front and rear ends is inscribed in the outer cylinder, and the inner cylinder is equipped with a plurality of intermediate push jacks. A flange of a joint cylinder having a ring-shaped flange at the front is fixed to the rear flange of the inner part, etc., and has a stepped portion with a small diameter at the front tip, and a cylindrical rear at the rear. A structure in which the step part of the rear cylinder formed by extending the ring is in contact with the flange of the joint cylinder through the thrust transmission material, shortens the overall length of the intermediate pressing device and bends at the joint cylinder even in the curved section Made possible. However, the problem of the long stepped portion with the small diameter of the second propulsion pipe T coming out from the rear end of the first propulsion pipe S which is the intermediate pushing device of the prior art has not been solved. The problem of inviting the collapse of the current situation has not been solved.
JP 2000-54786 A

  For this reason, the problem to be solved by the invention is to eliminate the step portion of the second propulsion pipe T coming out from the rear end of the annular body of the first propulsion pipe S at the time of normal propulsion construction in the intermediate pusher, thereby It is intended to provide safe and efficient propulsion work by preventing ground collapse.

The present invention is an intermediate pressing device for dispersing propulsive force acting in a concentrated manner on the rearmost end surface of the propulsion pipe in the propulsion method,
A front ring body having a cylindrical front step portion having a diameter smaller than the outer diameter of the propelling pipe at the front end portion and extending a cylindrical front cylinder having a long diameter substantially the same as the outer diameter of the propelling pipe at the rear thereof. The front step portion is inserted into the collar of the propulsion tube, has a long cylindrical rear step portion smaller in diameter than the outer diameter of the propulsion tube, and is provided with ring-shaped flanges at both front and rear ends of the rear step portion. In the circumferential direction of the inner peripheral surface of the stepped portion, a notch is provided in a portion where a plurality of intermediate press jacks are installed, and the others are provided with a concrete having substantially the same thickness as the propelling pipe wall body. A plurality of intermediate push jacks are installed in the notch, and a rear stepped portion of a rear ring formed by extending a cylindrical rear tube having the same diameter as the outer diameter of the propulsion pipe is provided behind the rear flange. Installed so as to be inscribed from the rear of the front cylinder of the body, the stepped portion of the propulsion pipe whose tip is smaller than the outer diameter of the propulsion pipe is placed in the rear cylinder of the rear ring A push device being constituted by off to.

  The front step portion provided at the front end of the front ring is manufactured with a diameter slightly smaller than the inner diameter of the collar fixed to the rear end of the forward propelling pipe, and is inserted into the collar and connected. The The length of the cylindrical front cylinder extending rearward is determined based on the length of the intermediate push jack body installed in the rear stepped portion, the stroke of the jack, and the like.

  The rear step portion of the rear ring is made slightly smaller than the inner diameter of the front cylinder of the front ring and is sized to be installed in the front cylinder. In the notch portion in the cylindrical rear stepped portion, there is an insert that is disposed in the circumferential direction so that the head of the intermediate pusher jack protrudes from the front flange, and is embedded in the concrete wall in advance. It is fixed by a fastener. The head of the intermediate push jack is brought into contact with the ring-shaped flange surface at the rear end of the front step portion. The bottom portion of the intermediate push jack is provided at a predetermined position in front of the rear flange so that the front cylinder and the rear stepped portion overlap each other by a predetermined length even when the intermediate push jack is extended and the connection inserted is not removed. It is in contact with the support plate.

The thrust force of the intermediate push jack is calculated by calculating the total thrust force before construction, and when the axial load bearing capacity of the propulsion pipe or the receiving pressure of the bearing wall is exceeded, the excess thrust force is exceeded by the intermediate push device. Will be responsible. Depending on the diameter of the propulsion pipe and the propulsive force it has, the capacity (ton tonnage) of the intermediate push jack and the number of jacks to be installed are determined.

  In the intermediate pressing device of the present invention, the intermediate pressing jack is installed in the rear step portion of the rear ring body, so that there is no step in the outer peripheral portion of the intermediate pressing device during normal propulsion construction, and the surrounding ground is not collapsed. For this reason, there is no increase in propulsive force due to the collapse of the ground, and propulsion with low propulsive force becomes possible. In addition, since the intermediate push jack is installed in the rear step part of the rear ring, the overall length of the intermediate pusher can be shortened and the curved part can be passed during curve propulsion, which is also effective for long-distance propulsion including curve propulsion. It becomes.

  In an intermediate pushing device for dispersing propulsive force that acts concentrated on the rear end face of the propulsion pipe, the intermediate push jack is installed by providing a notch in the concrete wall in the rear stepped portion. Since there is no step between the rear end of the tube and the rear end of the rear step, it is possible to construct the propulsion work safely and with low propulsion.

  FIG. 1 is a longitudinal sectional view illustrating an intermediate pressing device of the present invention. A front ring body having a cylindrical front step portion 3 having a diameter smaller than the outer diameter of the propelling tube at the front end portion and extending a cylindrical front tube 4 having a diameter substantially the same as the outer diameter of the propelling tube at the rear thereof. The two front step portions 3 are inserted into the collar of the propulsion pipe 12. It has a cylindrical long rear step portion 6 smaller in diameter than the outer diameter of the propulsion pipe, and is provided with ring-shaped flanges 8 at both front and rear ends of the rear step portion 6, and the circumferential direction of the inner peripheral surface of the rear step portion 6 Is provided with a notch in the portion where the plurality of intermediate push jacks 9 are installed, and the others are provided with a concrete wall 10 having substantially the same thickness as the wall of the propelling pipe 12. An intermediate push jack 9 is installed, and a rear stepped portion 6 of a rear ring body 5 is formed by extending a cylindrical rear tube 7 having a diameter substantially the same as the outer diameter of the propulsion pipe behind the rear flange 8. It is configured such that it is installed so as to be inscribed from the rear of the front cylinder 4 of the body 2 and a stepped portion of the propulsion pipe 12 whose tip is smaller than the outer diameter of the propulsion pipe is inserted into the rear cylinder 7 of the rear ring body 5. The intermediate pressing device 1.

  In order to prevent inflow of earth and sand or groundwater into the propulsion pipe 12, a ring-shaped water stop material is attached to the fitting portion between the collar of the front propulsion pipe 12 and the front step portion 3 of the front ring 2. (Not shown). A hard rubber material is used as a water stop material that is generally used, and is installed so as to contact both the inner peripheral surface of the collar and the outer peripheral surface of the front step portion 3. Between the rear end surface of the front propulsion pipe 12 and the front end surface of the front step portion 3 of the front ring body 2, a cushioning material is provided around the entire circumference so that the propulsive force can be transmitted evenly over the entire cross section with linear propulsion. is set up. In the case of propulsion work including curved line propulsion, curved cushion materials are installed vertically or horizontally in accordance with the curve conditions (not shown).

  The length of the front cylinder 4 of the front ring body 2 is determined by planning so that the front cylinder 4 and the rear stepped portion 6 overlap each other when the intermediate push jack 9 to be used is extended. Between the inner peripheral surface of the front cylinder 4 and the outer peripheral surface of the rear stepped portion 6, a water-stopping material made of the hard rubber material described above is attached to prevent inflow of earth and sand and groundwater into the propelling pipe 12 (illustrated). (Omitted). A notch is provided in the front flange 8 and the concrete wall 10 portion in the intermediate push jack 9 portion installed on the inner circumferential surface of the rear step portion 6 in the circumferential direction. The intermediate push jack 9 is disposed at a notch portion of the rear step portion 6 and is fixed by an insert and a fastener 11 embedded in the concrete wall body 10 in advance. The head of the intermediate jack 9 is arranged so as to protrude slightly forward of the front flange 8, is in contact with the ring-shaped flange at the rear end of the front step portion 3, and the bottom is a predetermined wall of the concrete wall 10. It is fixed in contact with a ring-shaped support plate provided at the position.

  A water stop material made of hard rubber is also mounted between the inner peripheral surface of the rear cylinder 7 of the rear ring 5 and the outer peripheral surface of the stepped portion provided at the tip of the rear propulsion pipe 12. Between the end face of the rear flange 8 of the rear stepped portion 6 and the stepped portion front end surface of the rear propelling pipe 12, a cushioning material is provided around the entire circumference so that the propulsive force can be transmitted evenly over the entire cross section with linear propulsion. is set up. In the case of propulsion work including curved line propulsion, curved cushion materials are installed vertically or horizontally in accordance with the curve conditions (not shown).

  FIG. 2 is a cross-sectional view illustrating the intermediate pressing device of the present invention. A front flange 8 and a concrete wall 10 are cut out in the rear stepped portion 6 of the rear ring body 5 at a predetermined interval in the circumferential direction. An intermediate push jack 9 is fixed to each notch portion by a fastener 11 and an insert embedded in the concrete wall 10 in advance. In the present embodiment, the case where the number of the middle push jacks 9 is ten is disclosed. However, among the total propulsion force examined before the construction, the middle push jack 9 has a propulsive force shared by the middle push device 1. Ability and number are decided.

  As described above, the intermediate pushing device of the present invention can be reliably propelled with low propulsive force without collapsing the ground around the middle pushing device, and thus can be applied to long distance propulsion and long distance propulsion including curves. .

It is a longitudinal cross-sectional view explaining the intermediate pressing apparatus of this invention. It is a cross-sectional view explaining the intermediate pressing apparatus of this invention.

DESCRIPTION OF SYMBOLS 1 Intermediate pushing device 2 Front ring body 3 Front step part 4 Front cylinder 5 Back ring body 6 Back step part 7 Back cylinder 8 Flange 9 Middle push jack 10 Concrete wall body 11 Fastening piece 12 Propulsion pipe

Claims (1)

In the propulsion method, an intermediate pressing device for dispersing propulsive force that acts concentrated on the rear end face of the propulsion pipe,
The front end of the front annulus, which has a cylindrical front step having a diameter smaller than the outer diameter of the propelling pipe at the front tip, and extends a cylindrical front cylinder that is substantially the same diameter as the outer diameter of the propelling pipe at the rear. The stepped portion is inserted into the collar of the propulsion pipe, has a long cylindrical rear stepped portion having a diameter smaller than the outer diameter of the propulsion tube, and is provided with ring-shaped flanges at both front and rear ends of the rear stepped portion. In the circumferential direction of the inner peripheral surface of the part, a notch is provided in a portion where a plurality of intermediate press jacks are installed, and the others are provided with a concrete having substantially the same thickness as the propelling pipe wall body. A plurality of intermediate push jacks are installed in the portion, and a rear stepped portion of a rear ring formed by extending a cylindrical rear cylinder having a diameter substantially the same as the outer diameter of the propulsion pipe is provided behind the rear flange. The stepped portion of the propulsion pipe whose tip is smaller than the outer diameter of the propulsion pipe is installed in the rear cylinder of the rear ring. Chu押 apparatus characterized by being constituted by off to.

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