JP2005320711A - Intermediate pusher - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an intermediate pusher capable of safely and surely carrying out pipe jacking work without flowing out of earth and sand or ground water into a pipe in an intermediate pushing pipe-jacking work under conditions of soft ground containing much ground water or including curved lines. <P>SOLUTION: The intermediate pusher comprises intermediate pushing pipes divided into plural numbers in the propulsive direction, a forward fixed lever closely connecting a plurality of levers in the circumferential direction so that a joint section between a forward internal wall of the front divided pipe of the intermediate pushing pipe and a backward internal wall of a front jacking pipe can serve as a fixed interval, a backward fixed lever closely connecting a plurality of levers in the circumferential direction so that a joint section between a backward internal wall of the rearmost divided pipe of the intermediate pushing pipe and a forward internal wall of a rear jacking pipe can serve as a fixed interval, an expansible sealant fixed in a ring-shape in the circumferential direction of the central part of a joint section of a plurality of intermediate pushers, an expansion lever enabling an interval of the joint section to make expansion at a fixed width to a plurality of joint sections located in positions of the intermediate pushers, a plurality of intermediate pushing jacks arranged in the circumferential direction on the intermediate circumferential surface of the expansion lever and a forward transfer means and a backward transfer mens installed to both front and rear ends of each intermediate pushing jack in order to transfer driving force to the end face of a front jacking pipe and the end face of a rear jacking pipe. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an intermediate pushing device that disperses a propulsive force for burying an excavator or a propulsion pipe in the ground in the middle portion of the propulsion pipe row without concentrating it on the rearmost end of the propulsion pipe. It is.

  The propulsion method is a method in which a propulsion pipe is buried in the ground while excavating the ground with a tip excavator. The propulsive force for advancing the excavator and the propulsion pipe is performed by a main pushing jack installed in the start shaft, and the force of the main pushing jack is applied from the rear end face of the propulsion pipe. The propulsive force consists of the face plate resistance force at the tip of the excavator and the friction resistance force between the outer periphery of the propulsion pipe and the surrounding ground. It is almost constant as long as there is no change in soil quality, but the frictional resistance increases in proportion to the propulsion distance. For this reason, as the propulsion distance becomes longer, the propulsive force gradually increases, and when the axial load bearing capacity of the propulsion pipe is exceeded, there arises a problem that the propulsion pipe is cracked or broken. As a countermeasure against this, an intermediate pushing device has been developed in which a plurality of intermediate pushing jacks are installed in advance on a joint portion in the middle of the propelling pipe row to reduce the propulsive force applied to the rear end face of the propelling pipe.

  As a configuration of the intermediate pushing device, an intermediate pushing device is formed between two pipe bodies adjacent to each other in the front-rear direction. In the cylindrical collar fixed to the rear end of the front propulsion tube, the tip step portion of the first tube having a step portion with a small diameter at the tip portion and extending a long ring at the rear is inserted. On the inner periphery of the ring body, a plurality of middle push jacks are evenly arranged in the circumferential direction and fixed to the inner wall of the ring body with metal fittings. In addition, a second tube having a long step portion with a small diameter at the tip and a collar into which the small step portion of the next propulsion tube can be inserted at the rear is inserted into the ring body to form a ring-shaped contact. It has a structure that abuts against the rear end of the intermediate push jack via a ring. A pair of sliding packings are mounted on the outer periphery of the second tube having a small diameter at the tip, and the structure smoothly slides with the inner peripheral surface of the ring of the first tube.

  The above-described conventional technology was able to construct a medium-pushing propulsion without any problem on a high-quality ground. However, under soft soil conditions with a lot of groundwater, the outside of the pipe is always exposed to groundwater. If the intermediate push is performed in this state, the groundwater enters with the earth and sand between the inner peripheral surface of the ring of the first tube and the outer peripheral surface of the second tube. In the structure of the intermediate pushing device, only a pair of sliding packings are mounted on the outer periphery of the second pipe and the inner peripheral surface of the ring of the first pipe, and the sealing effect is not sufficient. Can not be sufficiently prevented. In addition, due to frequent expansion and contraction work of the middle push jack, the pair of sliding packings are worn away by repeated sliding, or flipped up and swollen, so that the water does not stop, and groundwater and earth and sand flow into the pipe body. there were.

For this reason, a flexible tubular membrane member folded back in a substantially U shape is interposed behind the pair of sliding packings, and both ends of the tubular membrane member are respectively connected to the outer peripheral surface of the second pipe and the first. An intermediate pressing device has been developed that is fixed to the inner peripheral surface of the ring of the tube. However, as described above, in the narrow gap between the inner peripheral surface of the annular body of the first tube and the outer peripheral surface of the second tube, the tubular membrane member that is frequently slid repeatedly wears down, and sufficient water stoppage is generated. I can't. In particular, in the propulsion work including curve propulsion, there is a problem that a large partial pressure is applied to the tubular membrane member due to the bending, and the abrasion of the tubular membrane member also increases.
JP-A-3-2494

  The problem to be solved is to provide an intermediate pushing device that can be safely propelled even in the long-distance propulsion of soft soil with a lot of groundwater without the inflow of groundwater or earth and sand into the pipe.

  The present invention relates to an intermediate pushing device for dispersing propulsive force that acts concentratedly on the rearmost end surface of a propulsion pipe in the propulsion method, and an inner push pipe divided into a plurality in the propulsion direction, and a front inner wall of the first divided pipe of the intermediate push pipe And a front fixing rod in which a plurality of joints are arranged in a circumferential direction so that the joint portions are spaced at a constant interval, a rear inner wall of the rearmost division tube of the intermediate pusher tube, and a front of the rear propulsion tube A plurality of rear fixing rods that are tightly coupled in the circumferential direction so that the joint portions of the inner wall are at a constant interval, and a stretchable seal that is fixed in a ring shape in the circumferential direction of the central portion of the joint portion of the plurality of intermediate press pipes A plurality of intermediate presses disposed in a circumferential direction on the inner peripheral surface of the material, a plurality of joint portions of the plurality of intermediate press pipes, the joint portions being expandable and contractable with a constant interval between the joint portions A forward propelling pipe at the front and rear ends of the jack and the intermediate pushing jack The most important feature configured inner press apparatus by a front transfer means and the rear transmission means installed in order to transmit the driving force to the end face of the end face and the rear propulsion tube.

  In the divided intermediate pushing device of the present invention, the propulsive force is transmitted to the propulsion pipe before and after the intermediate push pipe through the intermediate push jack, so the propulsive force is not directly transmitted to the intermediate push pipe. Since the joint part of the leading split pipe and the forward propelling pipe of the intermediate pusher pipe and the rearward split pipe of the intermediate pusher pipe and the rear propulsion are fastened so as to maintain a constant distance, the joint part is slid by expansion and contraction. There is no use for operation, and the waterproof seal is not worn down. Further, when the forward propulsion pipe advances forward due to the extension of the intermediate push jack, the leading split pipe fastened by the fixing rod also advances, and the next split pipe fixed by the leading split pipe and the sealing material and the subsequent split pipe are also advanced. The tube is pulled forward. At this time, the joint portion of each divided pipe expands and contracts, but when it reaches a certain width, it is blocked by the expansion and contraction rod, and therefore expands and contracts within the allowable value of the sealing material. For this reason, the sealing material does not slide and wear away as in the prior art, but only expands and contracts within the allowable value at the joint part of each divided pipe, and reliably seals groundwater and earth and sand at the sealing material part. There is an advantage that you can.

  In the middle-push propulsion construction under soft soil conditions with a lot of groundwater, a push-pull device that can carry out the propulsion work safely and reliably without draining groundwater and earth and sand from the middle push-pipe section has been realized.

  FIG. 1 is a longitudinal sectional view for explaining an installation state of the intermediate pressing device of the present invention. A ring-shaped stretchable sealing material 3 is fixed in the circumferential direction at a predetermined interval at the center of the end face of each joint portion of the divided pipe 2 divided into four. In addition, a plurality of telescopic rods 5 that are controlled so that the interval between the joint portions does not open beyond a certain length are evenly tightened in the circumferential direction on the inner peripheral surface of each joint portion of each divided pipe 2. Is installed. A ring-shaped steel collar 6 is installed on the outer peripheral surface of each joint portion of each divided pipe 2 to prevent intrusion of earth and sand from the periphery. Install the front inner wall of the front split pipe 2 and the rear inner wall of the front propelling pipe 13 of the intermediate pusher pipe 1 so that the plurality of front fixing rods 4 are evenly connected in the circumferential direction so that the distance between the joint portions is constant. doing. Further, the plurality of rear fixing rods 4 are evenly connected in the circumferential direction so that the interval between the joint portions is constant between the rear inner wall of the rearmost division tube 2 of the intermediate pusher tube 1 and the front inner wall of the rear propulsion tube 14. It is installed to do. The leading end portion of the leading split tube 2 is fitted into a ring-shaped steel collar 15 attached to the outer periphery of the rear end of the forward propelling tube 13. A plurality of intermediate pushing jacks 7 are arranged in the circumferential direction on the inner periphery of the front split tube 2.

  An annular front abutment plate 9 made of steel or the like is installed at the tip of the intermediate push jack. A front transmission member 11 is disposed between the front contact plate 9 and the end surface of the propulsion tube 13 in order to transmit the intermediate push jack propulsion force from the front contact plate 9 to the rear end surface of the front propulsion tube 13. When the installation position of the front transmission member 11 matches the position of the intermediate push jack 7, the propulsive force can be transmitted effectively.

  A support member 8 made of steel or the like is arranged at the rear end of the intermediate push jack 7 and is in contact with an annular rear abutment plate 10 made of a rear steel member or the like. A rear transmission member 12 is installed between the rear abutment plate 9 and the front end face of the rear propulsion pipe 14. When the installation position of the rear transmission member 12 matches the position of the intermediate push jack 7, the propulsive force can be transmitted effectively.

  The number of the intermediate push jacks 7 to be installed is planned to be commensurate with the propulsive force handled by the intermediate push device by the propulsive force calculated from the construction conditions such as the propulsion extension and the soil condition. Further, the fixing rods 4 and the expansion rods 5 installed on the inner peripheral surface of the joint portion of each divided pipe 2 are studied so as to sufficiently withstand the propulsive force acting on the intermediate pushing pipe 1, and the strength and number thereof are determined. It is determined.

  The expansion / contraction amount of the ring-shaped sealing material 3 has an allowable value, and the number of the divided pipes 2 is increased or decreased so as to be within the allowable value, or the stroke length of the intermediate push jack 7 is adjusted. As a material of the sealing material 3, a synthetic rubber which is usually used as a water-stopping material is used.

  FIG. 2 is a cross-sectional view of the intermediate pressing device of the present invention. In the circumferential direction of the inner periphery of the split tube 2 that is the intermediate press tube 1, 18 intermediate press jacks 7 are equally arranged. An annular front abutment plate 9 is installed in front of the intermediate push jack 7, and a front transmission member 11 for transmitting a propulsive force from the head of the intermediate push jack 7 to the rear end face of the forward push pipe 13 is a circumferentially intermediate push jack. It is arranged at 7 positions.

  FIG. 3 is a vertical cross-sectional view for explaining the operation state of the intermediate pushing device. When the intermediate push jack 7 is extended, the front transmission member 11 is pushed forward by using the rear propulsion pipe 14 as a reaction force, and the front propulsion pipe 13 is advanced. At this time, the front split pipe 4 is also pulled forward by the front fixing rod 4 that binds the rear inner wall of the front propelling pipe 13 and the front inner wall of the front split pipe 2. As the leading split pipe 4 moves forward, the sealing material 3 at the rear end is extended. When the seal material 3 extends to an allowable value, the further opening is stopped by the telescopic rod 5 and the next split pipe 4 is pulled. In the same manner, the rear sealing material 3 extends to an allowable value and is stopped by the telescopic rod 5, and the next divided pipe is pulled. If the stroke length of the intermediate push jack 7 and the extension amount of all the sealing materials 3 are made the same, the water stoppage of the joint portion of each divided pipe can be secured.

  FIG. 4 is a longitudinal cross-sectional view showing the intermediate pushing portion after the completion of the propulsion. Before the completion of propulsion, the middle push jack 7 is finally extended, then the middle push jack 7 is reduced to remove the middle push jack 7 main body, the front transmission material 11, the rear transmission material 23, etc., and the main push jack in the shaft (not shown) ), The opening of the joint portion between the front and rear of the intermediate push tube 1 and the propulsion tubes 13 and 14 is closed by pushing the propulsion tube forward, and the joint portion of each divided tube 4 is shortened to a predetermined width.

  It can be applied to a center pushing device that can safely carry out the propulsion work by completely preventing the outflow of earth and sand and ground water in the pipe in the soft pushing condition including soft ground conditions with many groundwaters and curves.

It is a longitudinal cross-sectional view explaining the installation situation of the intermediate pushing apparatus of this invention. It is a cross-sectional view of the intermediate pressing device of the present invention. It is a longitudinal cross-sectional view explaining the operation | movement condition of a middle pressing apparatus. It is a longitudinal cross-sectional view which shows the intermediate pushing part after completion of a promotion.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Middle push pipe 2 Divided pipe 3 Seal material 4 Fixed rod 5 Expansion / contraction collar 6 Divided tube steel collar 7 Middle push jack 8 Support material 9 Front abutment plate 10 Back abutment plate 11 Front transmission material 12 Rear transmission material 13 Front propulsion tube 14 Backward propulsion Tube 15 Color made of propulsion tube steel

Claims (1)

  In an intermediate pushing device for dispersing propulsive force that acts concentratedly on the rearmost end surface of the propulsion pipe by the propulsion method, the inner push pipe divided into a plurality of directions in the propulsion direction, the front inner wall of the front divided pipe and the forward propulsion A plurality of front fixing rods that are joined together in the circumferential direction so that the joint portions are spaced at regular intervals, and a joint portion between the rear inner wall of the rearmost divided tube of the intermediate pusher tube and the front inner wall of the rear propulsion tube A plurality of rear fixing rods tightly coupled in the circumferential direction so as to have a constant interval, a stretchable sealing material fixed in a ring shape in the circumferential direction of the central portion of the joint portion of the plurality of intermediate press pipes, and An expansion rod that can be expanded and contracted with a certain length of joint portions at a plurality of joint portions of the plurality of intermediate press tubes, and a plurality of intermediate press jacks arranged in the circumferential direction on the inner peripheral surface of the expansion rod, An end face of the forward propelling pipe at the front and rear ends of the intermediate push jack; The inner press apparatus characterized in that it is constituted by a front transfer means and the rear transmission means installed in order to transmit the driving force to the end face of the square propulsion tube.

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