JPH11336477A - Pipe end reinforcing structure of reinforced concrete pipe for pipe jacking method, and method for forming reinforced concrete pipe for pipe jacking method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase propulsion forces by precisely transmitting propulsion forces to an end surface of a Hume pipe, to which propulsion forces are directly applied, in a long distance curved pipe jacking method. SOLUTION: An end 51 of an axial bar 5 is welded close to the center of the rear side of a steel plate 4 and a spiral bar 6 is disposed around the bar 5 to weld an end of the bar 6 to the end 51 of the bar 5, forming a reinforcing unit 3. And the units 3 are disposed symmetrically with respect to the circumferential direction of a reinforced concrete pipe 1, at each of the axially opposite ends of the pipe 1, with the front surface of each steel plate 4 being positioned at the end surface 11 of the pipe 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe end reinforcing structure of a reinforced concrete pipe for a propulsion method in a long-distance curve propulsion method such as a method of propelling a sewer pipe, and a method of forming a reinforced concrete pipe for a propulsion method.

[0002]

2. Description of the Related Art In a conventional propulsion method, as shown in FIG. 12, a machine d such as an excavator is arranged in a propulsion direction, and a propulsion pipe c is propelled by moving straight from a start shaft a to an arrival shaft b.
A straight-line construction in which thrust is uniformly applied to the entire end face of the propulsion pipe c has been performed, but the curve propulsion method as shown in FIG. Has been migrated to. In the case of this curved construction, the material that locally transmits thrust to a part of the pipe end is, for example, a hinge material, styrene foam which is naturally deformed when thrust is applied, or a plastic deformable (elastic) material, jack, or the like. As shown in FIG. 14, a thrust is partially loaded on the upper and lower sides e of the end face of the propulsion pipe c. Further, in the case of a curved construction, as shown in FIG.
The tube is coated with steel to increase the strength and the tube thickness is increased.

[0003]

However, the conventional technique has the following problems. In the case of the curved construction method, the same thrust S as in the case of the straight construction method is concentrated on a part of the pipe end, so that there is a problem that the pipe end is broken. Therefore, as a result of designing and constructing to prevent breakage of the pipe end, there is a problem that only a small thrust can be transmitted and long-distance propulsion cannot be performed. In other words, in the case of curved construction, there is a problem that even if high-strength concrete is used, the effect of increasing the total propulsion cannot be expected when partial loading is performed by the thrust transmitting members arranged left and right or up and down. As a method of solving the above method, a method of increasing the strength of concrete and forming it into high-strength concrete As shown in FIG. 15, a method of covering the outer peripheral surface of a reinforced concrete pipe c with a steel pipe f to increase the strength The pipe thickness is increased. There is a method to increase the strength of the whole pipe such as a method. However, all of them have a problem that manufacturing and construction costs are high. Therefore, the present invention, in the long-distance curve propulsion method,
It accurately transmits the propulsion force, effectively distributes stress to the pipe,
An object of the present invention is to provide a pipe end reinforcing structure for a reinforced concrete pipe for a propulsion method and a method for forming a reinforced concrete pipe for a propulsion method for increasing a propulsion force.

[0004]

According to a first aspect of the present invention, there is provided a pipe end reinforcing structure for a reinforced concrete pipe for a propulsion method, wherein one end of an axial bar is welded to substantially the center of the back surface of a steel plate. And a reinforcing unit formed by disposing a spiral streak around the axial streak, and welding one end of the spiral streak to one end of the axial streak, so that the surface of the steel plate is positioned on the tube end face side. It is characterized in that it is located at circumferentially symmetric positions at both axial ends of the reinforced concrete pipe. According to a second aspect of the present invention, there is provided a pipe end reinforcing structure for a reinforced concrete pipe for a propulsion method, wherein the reinforcing unit according to the first aspect includes an axial streak having one end disposed at the end of the tube, and a center around the axial streak. And a spiral streak welded to one end of the axial streak. According to a third aspect of the present invention, there is provided a pipe end reinforcing structure for a reinforced concrete pipe for a propulsion method, wherein the reinforcing unit according to the first or second aspect is arranged at symmetrical positions in the circumferential direction at both ends in the axial direction of the reinforced concrete pipe. Features. According to a fourth aspect of the present invention, there is provided a pipe end reinforcing structure for a reinforced concrete pipe for a propulsion method, wherein the reinforcing unit according to the first aspect is configured such that axial reinforcements are arranged substantially in parallel on a back surface of a steel plate at predetermined intervals. One end is welded, a spiral streak is arranged around each axial streak, and one end of the spiral streak is welded to one end of the axial streak. According to a fifth aspect of the present invention, there is provided a pipe end reinforcing structure for a reinforced concrete pipe for a propulsion method, wherein a steel collar having a diameter slightly larger than an outer diameter of an insertion port is provided at a receiving portion of the reinforced concrete pipe according to the first, second or third aspect. It is characterized by having been established.

According to a sixth aspect of the present invention, there is provided a method of forming a reinforced concrete pipe for a propulsion method, wherein one end of an axial bar is welded to substantially the center of the back surface of a steel plate, and a spiral bar is provided around the axial bar. A reinforcing unit formed by welding one end of the spiral streak to one end of the axial streak is disposed at a circumferentially symmetric position of the reinforced concrete pipe with the surface of the steel sheet positioned on the form end face plate side. It is characterized by being formed by centrifugal force. According to a seventh aspect of the present invention, there is provided a method of forming a reinforced concrete pipe for a propulsion method, wherein the surface of the steel plate according to the sixth aspect is fixed to an inner surface of a form end plate by a predetermined means. In the method for forming a reinforced concrete pipe for a propulsion method according to the invention of claim 8, an axial streak having an internal thread formed at one end in an axial direction is fixed to a form end face plate by a bolt provided with a male thread corresponding to the female thread. Spiral streaks are arranged around the axial streaks, and a reinforcing unit formed by welding one end of the spiral streaks to one end of the axial streaks is positioned at a circumferentially symmetric position of the reinforced concrete pipe 1. It is characterized by being arranged and formed by centrifugal force.

[0006]

[Effect] The effect of reinforcing the concrete by filling the concrete with the axial streaks surrounded by the spiral streaks around the axial streaks (hereinafter referred to as the restraining effect), so that even in the case of long-distance curve propulsion, the propulsion force is reinforced. It functions to accurately transmit to the pipe and effectively distribute stress to the pipe. The stress distribution state is as shown in the plan view of the description of the transmission of thrust in the reinforced concrete pipe 1 of FIG.
When the propulsion S is transmitted to the pipe, the propulsion is distributed as shown by the dashed line reinforcement range W, the dashed line portion is reinforced and is not damaged, and even in the case of curved construction where thrust is applied to the left, right, up and down of the pipe end. Is accurately transmitted and propelled.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 to 11 relate to an embodiment of the present invention, and FIGS. 1 to 3 relate to a pipe end reinforcing structure of a reinforced concrete pipe for a propulsion method according to the first aspect of the present invention. It is. The reinforcing unit 3 for reinforcing the pipe end 11 of the reinforced concrete pipe 1 welds one end 51 of the axial streak 5 to substantially the center of the back surface of the steel plate 4 and welds the axial streak 5.
A spiral streak 6 is arranged around the center of the spiral streak, and one end 61 of the spiral streak 6 is welded 8 to one end 51 of the axial streak 5. The reinforcing unit 3 is arranged at circumferentially symmetric positions at both axial ends of the reinforced concrete pipe 1 with the surface of the steel plate 4 positioned on the pipe end face 11 side. The steel plate 4 is formed into a sector shape, and the axial reinforcing bar 5 is preferably a deformed steel reinforcing bar provided with a number of nodes in the axial direction. Further, the pitch of the spiral streaks 6 is preferably fine within a range that does not adversely affect the centrifugal molding. Specifically, in the case of a 800 mm nominal diameter propulsion pipe (length 2430 mm, pipe thickness 80 mm),
The steel plate 4 has a thickness of about 5 to 10 mm, and the pitch of the spiral streaks 6 is preferably, for example, about 25 to 30 mm. The reinforcing unit 3a according to claim 2 is
As shown in FIG. 10, the reinforcing unit 3 does not use the steel plate 4. The reinforcing unit 3a is disposed around the axial line 5 with one end 51 disposed at the tube end 11 and one end 51 disposed in the axial direction of the reinforced concrete pipe 1 and one end 61 is disposed around the axial line 5. A spiral streak 6 welded to one end 51 of the axial streak 5. Also, the reinforcing units 3 and 3a are located at circumferentially symmetric positions at both ends in the axial direction of the reinforced concrete pipe 1 as shown in FIGS. 1 and 2, or at vertical and left and right symmetric positions as shown in FIGS. The propulsion pipe is arranged to have a structure corresponding to a complicated vertical and horizontal bending of the propulsion pipe. According to the experimental results, it is preferable that the axial streaks 5 of the reinforcing unit 3 have a length of about three times or more the tube thickness, and the diameter of the spiral streaks 6 is approximately 0.5 times the tube thickness. As shown in FIGS. 1 and 4, a steel collar 2 having a diameter slightly larger than the outer diameter of the insertion port 13 is provided in the receiving port 12 of the reinforced concrete pipe 1 to increase the restraining effect ( Claim 5).

Next, as shown in FIG. 8, a method of forming a reinforced concrete pipe for the propulsion method is to weld one end 51 of the axial bar 5 to almost the center of the back surface of the steel plate 4 and to attach the axial bar 5 to the steel plate 4. A spiral streak 6 is arranged around the center and one end 61 of the spiral streak 6 is connected to one end 51 of the axial streak 5.
The reinforcing unit 3 welded to the steel plate 4 is disposed at the symmetric position in the circumferential direction of the reinforced concrete pipe with the surface of the steel plate 4 positioned on the side of the mold end face plate 7 and formed by centrifugal force. In the above case, the steel plate 4 is fixed to the form end plate 7 with bolts 73 (FIG. 8) or double-sided tape 74 (FIG. 9) and is formed (claim 7). As shown in FIG. 9, the axial streak 5 having the female screw 51 formed in the axial direction at one end 51 is fixed to the form end plate 7 with the bolt 71 provided with the male screw 72 corresponding to the female screw 51. A reinforcing unit 3a formed by disposing a spiral streak 6 around the axial streak 5 and welding 8 one end 61 of the spiral streak 6 to one end 51 of the axial streak 5 is a reinforced concrete pipe. Are arranged at symmetrical positions in the circumferential direction, and are formed by centrifugal force. FIGS. 6 and 7 show a case in which two sets of axial reinforcements 5 and spiral reinforcements 6 are provided on the steel plate 4 in order to enhance the restraining effect and strengthen the pipe end. The axial streaks 5 are arranged substantially in parallel at predetermined intervals, and each of the axial streaks 5
Is spirally arranged around the respective axial streaks 5, and one end 61 of the spiral streaks 6 is welded to one end 51 of the axial streaks 5. . The space between the spiral muscles 6 is preferably set to be approximately twice as large as the diameter of the spiral muscle 6.

[0009]

Since the present invention is configured as described above, the following effects can be obtained. Due to the restraining effect of the reinforcing unit that strengthens the pipe end of the reinforced concrete pipe at the part loaded around the axial streaks and surrounded by spiral streaks, the pipe end face of the reinforced concrete pipe is reinforced in the case of long distance curve propulsion method The propulsion force is accurately transmitted to the reinforced concrete pipe without being damaged by being strengthened by the unit, the stress is effectively distributed to the pipe body, and the propulsion force can be increased. Since the steel plate is arranged so as to be exposed at the end face of the pipe, the portion for transmitting the propulsion force can be accurately identified, and the working efficiency can be improved. In the long-distance curve propulsion method, the thrust can be accurately transmitted to the end surface of the fume pipe on which the thrust of the jack directly acts to increase the thrust. A steel pipe collar is provided at the reinforced concrete pipe socket,
In addition, since the reinforcing unit is provided at the end of the pipe, the restraining effect can be increased. Long-distance curve propulsion can be performed at low cost, and the propulsion pipe can be manufactured at low cost by providing a reinforcing unit.

[Brief description of the drawings]

FIG. 1 is a partially cutaway sectional view of a first embodiment of the present invention.

FIG. 2 is a left side view of the reinforced concrete pipe of the first embodiment.

FIG. 3 is an enlarged view of a main part of the reinforcing unit.

FIG. 4 is a partially cutaway sectional view of a second embodiment of the present invention.

FIG. 5 is a left side view of a reinforced concrete pipe according to a second embodiment.

FIG. 6 is a cross-sectional view when two reinforcing units are provided side by side.

FIG. 7 is a left side view of a reinforced concrete pipe provided with two reinforcing units.

FIG. 8 is an explanatory view of a first embodiment of a molding method.

FIG. 9 is an explanatory view of a second embodiment of the molding method.

FIG. 10 is an explanatory view of a third embodiment of the molding method.

FIG. 11 is an explanatory diagram of thrust transmission.

FIG. 12 is an explanatory view of a conventional straight line construction.

FIG. 13 is an explanatory view of a conventional curve construction.

FIG. 14 is an explanatory diagram of a loading location in the case of curved construction.

FIG. 15 is a cross-sectional view of a conventional reinforced concrete pipe whose outer peripheral surface is covered with a steel pipe.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reinforced concrete pipe 11 Pipe end 12 Reception part 13 Insertion part 2 Steel pipe collar 3 Reinforcement unit 4 Steel plate 5 Axial streak 6 Spiral streak 7 Form end face plate 8 Welding

Claims (8)

[Claims] At least one end of an axial streak is welded to substantially the center of the back surface of a steel sheet, and a spiral streak is arranged around the axial streak, and one end of the spiral streak is connected to one end of the axial streak. A pipe end of a reinforced concrete pipe for a propulsion method, wherein a reinforcing unit welded to an end is arranged at circumferentially symmetric positions at both axial ends of the reinforced concrete pipe with the surface of the steel plate positioned on the pipe end face side. Reinforcement structure. 2. The reinforcing unit according to claim 1, wherein one end is disposed at an end of the pipe at an end thereof, and the reinforcing bar is disposed around the axial streak, and one end is welded to one end of the axial streak. A pipe end reinforcing structure for a reinforced concrete pipe for a propulsion method, comprising: a spiral spiral bar. 3. A pipe end reinforcing structure for a reinforced concrete pipe for a propulsion method, wherein the reinforcing unit according to claim 1 or 2 is arranged at circumferentially symmetrical positions at both ends in the axial direction of the reinforced concrete pipe. 4. The reinforcing unit according to claim 1, wherein the axial streaks are arranged substantially parallel to the back surface of the steel plate at predetermined intervals, one end of each of the axial streaks is welded, and the axial streaks are centered. And a spiral streak disposed around the periphery thereof, and one end of the spiral streak is welded to one end of the axial streak. 5. A reinforcing method for a reinforced concrete pipe for a propulsion method, wherein a steel collar having a diameter slightly larger than an outer diameter of an insertion port is provided in a receiving portion of the reinforced concrete pipe according to claim 1, 2, or 3. Construction. 6. One end of an axial streak is welded to substantially the center of the back surface of the steel sheet, and a spiral streak is disposed around the axial streak, and one end of the spiral streak is connected to one end of the axial streak. A reinforced concrete pipe for a propulsion method, wherein a reinforcing unit welded to an end is disposed at a circumferentially symmetric position of the reinforced concrete pipe with the surface of the steel sheet positioned on the form end face plate side, and formed by centrifugal force. Molding method. 7. The method of forming a reinforced concrete pipe for a propulsion method according to claim 6, wherein a surface of the steel sheet according to claim 6 is fixed to an inner surface of a form end plate by a predetermined means. 8. An axial streak having an internal thread formed on one end thereof is fixed to a form end face plate with a bolt provided with a male thread corresponding to the female thread. A reinforcing unit formed by arranging a spiral streak and welding one end of the spiral streak to one end of the axial streak is arranged at a circumferentially symmetric position of the reinforced concrete pipe 1 and formed by centrifugal force. Forming method of reinforced concrete pipe for propulsion method.