JP2002081290A - Execution work method of jacking pipe - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an execution work method of a jacking pipe capable of manufacturing the jacking pipe at a job site, capable of coping with the manufacturing equipment by simple equipment such as a form, a crane, a placing base and a scaffold and efficiently performed up to carrying-in to a shaft from molding. SOLUTION: This system has a field molding process of molding the jacking pipe by placing highly fluid concrete in a vertical form 1 on the gound in the vicinity of the shaft, a field curing process of curing the jacking pipe by horizontally placing the molded jacking pipe 2 in a curing yard of the job site and a jacking process of jacking the jacking pipe by lowering the cured jacking pipe in the shaft.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing a propulsion pipe for propelling and adding a propulsion pipe from a shaft while excavating a tunnel with an excavator.

[0002]

2. Description of the Related Art Conventionally, like a fume pipe, a propulsion pipe used for propulsion work is an off-the-shelf product manufactured at a factory, and is used in accordance with a standard (shape, proof strength, etc.). A suitable product was selected and used. In the manufacturing method, similarly to telephone poles, PC piles, etc., molding using centrifugal force is performed at a factory using a horizontal mold.

[0003] That is, as shown in FIG.
0 is set in the horizontal mold 101, concrete is poured into the horizontal mold 101, and the concrete is compacted by centrifugal force to perform steam curing. After the aerial curing, they are transported by heavy trailer from the factory to the site because they are heavy.

In this case, high-strength hardened concrete with a small slump is used, and a reinforced basket 10 is used.
The reinforcement arrangement of 0 is performed by winding a thin round steel or PC steel wire spirally around a longitudinal (axial) reinforcement.

[0005]

However, there are the following problems. Conventionally, since the standard of the propulsion pipe is determined, it is not possible to use the optimum propulsion pipe for each construction such as the shape, dimensions, and load.
Under load conditions (visual acuity, partial pressure at curved parts, earth pressure, internal water pressure, etc.) that exceed the standard in proof stress, it is necessary to use special pipes such as special thick pipes and synthetic pipes, It will increase the cost.

[0006] As for the shape, since the vehicle is transported via a general road, the size is determined by the width, height limitation, and weight of the vehicle (the maximum outer diameter is 3.5 m and the length is 2.43.
m). In the conventional manufacturing method, centrifugal molding is performed, so that manufacturing other than the ring shape is difficult. Since there is no formwork inside, plastering finish etc. is required separately after the casting, and it is difficult to attach inserts and the like.

[0007] Depending on the use of the tunnel, construction such as inverting is post-construction. Using traditional manhole formwork on site,
Although it is conceivable to manufacture a propulsion pipe using hardened concrete, it is possible to construct a thin structure with ease (such as assembling / demolding formwork,
It is difficult to manufacture with satisfactory supporting method, moving method, casting cycle, detailed structure such as collar and caulking groove) and quality (strength, dimensional accuracy, filling property, surface finish, etc.).

Therefore, an object of the present invention is to provide a method for manufacturing a propulsion pipe on site so as to eliminate the problems of transporting the propulsion pipe and of a standard product. Another object of the present invention is to provide a method of constructing a propulsion pipe that can be handled by simple equipment such as a scaffold and the like, and that can efficiently carry out from molding to loading into a shaft.

[0009]

SUMMARY OF THE INVENTION A method for constructing a propulsion pipe according to the present invention comprises a field molding step of casting high-fluidity concrete into a vertical formwork on the ground near a shaft to form a propulsion pipe, and a molded propulsion pipe. It has a site curing process in which the pipes are placed sideways in a curing yard at the site for curing, and a propulsion process in which the cured propulsion tubes are lowered into the shaft and propelled.

In the on-site molding step, a grout hole also used for hanging, a grout hole also used for rollover, and internal components such as an invert portion and a partition wall are simultaneously formed on the propulsion tube.

If a high-performance AE water reducing agent composed of a complex of a polycarboxylic acid ether and an intramolecularly crosslinked polymer is used as the water reducing agent, the slump flow and the retention of the slump flow are required when the propulsion pipe is manufactured on site. It is easy to adjust the time to the target value.

When the composition of the high fluidity concrete is set as follows, the target quality as the high fluidity concrete for a propulsion pipe used in the construction method of the present invention is satisfied. Unit water amount: 155 to 175 kg / m ³ unit Cement amount: 450 to 600 kg / m ³ unit fine aggregate amount: 780 to 910 kg / m ³ (specific gravity 2.6
Case) unit coarse aggregate amount: 810 to 945 Kg / m ³ (specific gravity 2.7)
Case) High-performance AE water reducing agent: 0.5 to 2.5% based on water

[0013]

Next, embodiments of the present invention will be described in detail with reference to the drawings.

According to the present invention, from the production of a propulsion pipe to the loading of the same into a shaft, the operation is performed on site, and FIG. 2 shows a layout of a production operation of the propulsion pipe on site. The work place is roughly divided into material storage / rebar processing / assembly yard A and molding yard B
And a curing / storage yard C.

The material storage / rebar processing / assembly yard A is a work place for storing and processing the material of the rebar cage and assembling the vertical formwork. The rebar basket and the vertical formwork assembled here are: For example, it is lifted by a crawler crane and transported to the molding yard B. In the molding yard B, the reinforcing cage is suspended in the vertical form 1 and high-fluidity concrete is poured into the vertical form 1 by a concrete pump as described later to form the propulsion pipe 2 in a vertical posture. . The removed vertical mold 1
Move to another space in the molding yard B and cast high-fluid concrete again. The formed propulsion pipe 2 is lifted off by a crawler crane and removed from the mold.
The air is cured in the aerial, and as shown in FIG. 3, it is sequentially lifted from the cured propulsion pipe 2 and lowered into a shaft. FIG.
Shows the flow of the manufacturing process of the propulsion pipe at the site. The propulsion work of the propulsion pipe from the shaft and other incidental works are the same as those in the related art as shown in FIG.

FIG. 6 shows a simplified cross section of the formed propulsion pipe 2 in an upright state. The propulsion pipe 2 is provided with, for example, two hanging and grout holes 3 which are also used for lifting the propulsion pipe 2 in the axial direction, and the propulsion pipe 2 is mounted on the opposite side (180 ° reverse direction). The rollout and grout hole 4 which is also used for rollover is provided.

FIGS. 7 and 8 show an example of the structure of the vertical mold 1 for molding the propulsion pipe 2 having such a configuration. Vertical formwork 1
Is made of steel, and inner and outer skin plates 5.6 are arranged in a double cylindrical shape with vertical and horizontal ribs 7.8, a plurality of support jacks 9 and tightening bands 10, and these inner and outer skin plates 5.6 are formed. In the meantime, after installing the reinforcing bar 11, high-fluidity concrete is poured. The vertical formwork 1 has a hinge structure of about three divisions in the circumferential direction so as to be easily assembled and removed. Because it is not centrifugal molding, the inner and outer skin plates 5.6
A jig for attaching an accessory such as an insert can be provided on the surface. In FIG. 7, reference numeral 12 denotes a fixing hardware for maintaining a perfect circle;
Reference numeral 13 denotes a collar support ring.

FIG. 9 shows an example of a mold structure for molding the propulsion pipe 2. This formwork has a pin structure and 3
It is divided into two parts in the vertical direction.

Further, if the vertical formwork 1 is divided into two or three parts vertically in the form of a ring, a propulsion pipe having a length of 1/2 or 1/3 can be easily formed. By incorporating the shoring in the vertical mold 1, deformation can be suppressed. Further, a rigid base plate is provided at the bottom for easy positioning with a pin or a tenon, and for maintaining roundness. Top,
A ring-shaped rib or the like is also provided at the intermediate portion in order to increase circumferential rigidity.

The caulking groove and the sealing groove of the propulsion tube are dealt with by providing a projection on the vertical mold. For the collar, a T-type collar that is attached later can also be used, but detachable ribs and rods that support the collar are provided on the outer mold (outer skin plate) so that the embedded collar can be attached. While maintaining the perfect circle when assembling the formwork, insert it into the formwork from above and fix it with fixing hardware.

The shape of the propulsion pipe 2 is not limited to a normal cylindrical shape, but may be a shape obtained by integrally molding an invert portion 2a as shown in FIGS. 10A, 10B and 10C, respectively.
1 (A), the inner floor 2b as shown in FIG. 1 (B) and the partition 2c as shown in FIG. 1 (B) can be cast into any shape such as a box shape, a horseshoe shape or an elliptical shape. .

As for the reinforcing bar, a conventional spiral PC steel bar or round bar can be used, but a deformed bar can be used by a simple combination of a hoop bar and a straight bar in the axial direction of the tunnel. . Therefore, it is possible to increase or decrease the amount of the reinforcing bar in accordance with the generated sectional force. In addition, around the pipe end or grout hole where thrust or bias is likely to act, furthermore, a branch pipe mounting part having a broken circular structure as shown in FIG. 12A, or a manhole joint as shown in FIG. about,
Reinforcement of steel bars and steel frames can be given in advance if necessary.

For concrete casting, σck = 50N
When high-strength concrete of not less than / mm ² is cast, ordinary concrete becomes quite hard concrete. In addition, since the thickness is as thin as 250 mm or less and the height of the formwork is also 2 m or more, the workability of compacting with a vibrator is poor in ordinary concrete.

Therefore, a high-fluidity concrete that does not require vibration compaction and is self-filled to every corner is used. Even in the existing ready-mixed concrete plant, it is possible to manufacture high-fluid concrete by changing only the additives. Powder-based high fluidity concrete has a high strength (60 to 70 N / mm ² ) and is therefore most suitable for concrete of a propulsion pipe. However, in high-fluidity concrete, since air inside the concrete is difficult to escape, there is a possibility that air bubbles will occur on the finished surface. For this purpose, it is advisable to take measures such as making a slit in the mold to release air bubbles.

The casting method is based on the premise that high-fluidity concrete is used.
Use a pump, chute, etc. to keep it within.
As for the moving distance, when the circumferential length becomes longer, the driving is performed from a plurality of locations.

Regarding the method of moving the formed propulsion pipe 2, the hanging and grouting holes 3 are provided at two places in the axial direction. However, since they are suspended in the vertical direction, the rolling and grouting holes 4 are turned upside down by 180 degrees for rollover. The direction has been added. In the case of a large-sized and heavy-weight, a grout hole for lifting is added or a fall-over device is provided.

Since high-fluidity concrete generally has a low strength, the mold is removed 24 hours after casting, the mold is moved to another space, and concrete is cast.

The present inventors have conducted various tests on the quality of the high fluidity concrete for a propulsion pipe from the viewpoint of manufacturing the propulsion pipe on site as described above, and as a result, as shown in Table 1 below. We have come to the conclusion that the conditions are favorable.

[0029]

[Table 1]

As a target quality, a variety of selections were made with respect to the composition of the high-fluidity concrete, and tests were conducted. As a result, a high-performance AE comprising a complex of a polycarboxylic acid ether and an intramolecularly crosslinked polymer was used as a water reducing agent. It has been found that the water reducing agent can be easily adjusted to the target value in terms of the slump flow and the holding time. In addition, this kind of high-performance AE
The water reducing agent has the advantage that the slump flow retention time and the strength increase setting can be freely adjusted by changing the blending amount of the intramolecular crosslinked polymer.

Table 2 shows that three types of high-performance AE water reducing agents A, B, and C having different blending amounts of the intramolecular crosslinked polymer were used, and water (W), cement (C), and fine aggregate (S) were used. ), The amount of coarse aggregate (G) is the same for the three types, and the slump flow and the slump flow holding time are measured for each of the three types at two points in the perpendicular direction (X direction and Y direction). The three types of high-performance AE water reducing agents A, B, and C all used "Leobuild SP 8SB Series" manufactured by NMB Corporation, and the cement used was low heat Portland cement manufactured by Taiyo Cement Co., Ltd.

[0032]

[Table 2]

From Table 2, in the case of the high-performance AE water reducing agent of A, if the ratio to the cement is 1.35%, the slump flow and the slump flow holding time are the target. In the case of the high performance AE water reducing agent of C, the slump flow retention performance of C is higher than that of B, and the high performance AE water reducing agent of C is 1.6% with respect to the cement.
Best when used.

When a compressive strength test was performed on the high performance AE water reducing agent of A and the high performance AE water reducing agent of C, as shown in Table 3 below, the curing time was reduced from 20 ° C. to 30 ° C.
By raising the temperature by ° C., the target strength value of 42 hours was satisfied in 18 hours.

[0035]

[Table 3]

[0036]

According to the present invention, the following effects can be obtained. By using high fluidity concrete and devising the formwork (division, hinge structure, securing rigidity, mounting jigs for accessories, etc.), a propulsion pipe with the same shape and quality as the current propulsion pipe can be easily created on site. Can be manufactured. Because it is manufactured on site, it is possible to reduce transportation costs. If the formwork such as the attachment of the collar and the seal groove is made detachable and the formwork can be divided in the tunnel axis direction, the manufacture of 1/2 pipe and 1/3 pipe can be facilitated. Since pipes longer than conventional pipes can be easily manufactured, it is possible to reduce costs by reducing the number of joints, and at the same time, it is possible to shorten the construction period by reducing the number of pipe installations. The thickness of the propulsion pipe and the reinforcing steel can be set freely according to the load conditions (similar to segments). Since there is an inner formwork, it is possible to install inserts and simultaneously drive inverts. The propulsion method with a diameter of 3m or more can be applied, and the cost of sewer construction can be reduced. Similarly, it is possible to manufacture a propulsion pipe having a shape such as a box or a horseshoe. It is also possible to attach accessories such as inserts or to cast inverts together, thereby shortening the installation process.

Further, by using a high-performance AE water reducing agent comprising a complex of a polycarboxylic acid ether and an intramolecularly crosslinked polymer as a water reducing agent for the high fluidity concrete to be used, a high fluidity concrete for a propulsion pipe manufactured on site can be obtained. The target quality can be met.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a conventional method for manufacturing a propulsion pipe.

FIG. 2 is a layout diagram of a manufacturing operation of a propulsion pipe according to the present invention.

FIG. 3 is an explanatory view showing a process from molding of a propulsion tube to loading into a shaft.

FIG. 4 is a flowchart showing a flow of a manufacturing process of a propulsion pipe at a site.

FIG. 5 is an explanatory view of a construction method of a propulsion pipe.

FIG. 6 is a simplified sectional view of a propulsion tube.

FIG. 7 is a longitudinal sectional view of a vertical mold for molding a propulsion tube.

FIG. 8 is a plan view of the same.

FIG. 9 is a plan view of an example of a mold for molding a propulsion tube.

FIGS. 10A, 10B, and 10C are end views of a propulsion pipe having an invert portion.

FIG. 11A is an end view of a propulsion pipe having an intermediate floor.
(B) is an end view of the propulsion pipe having a partition.

12A is a cross-sectional view of a propulsion pipe used for a branch pipe mounting portion having a broken circle structure, and FIG. 12B is a cross-sectional view of a propulsion pipe used for a manhole joint.

[Explanation of symbols]

 Reference Signs List A Material storage / rebar processing / assembly yard B Molding yard C Curing / storage yard 1 Vertical formwork 2 Propulsion pipe 2a Inverted section 2b Middle floor 2c Partition wall 3 Suspended and used grout hole 4 Rollover and used grout hole 5.6 Inside and outside skin plate 7.8 Vertical and horizontal ribs 9 Support jack 10 Tightening band 11 Reinforcing cage 12 Fixing hardware for maintaining perfect circle 13 Color support ring

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) C04B 24:04 C04B 24:04 24:24 24:24 A 24:26 24:26 E H 24:28 24:28 A 24:32 24:32 14:02) 14:02) Z 111: 56 111: 56 (72) Inventor Tsutomu Hagiwara 2-5-8 Kitaaoyama, Minato-ku, Tokyo Intra-company group (72) Inventor Taniguchi Hiroshi 2-5-8 Kita-Aoyama, Minato-ku, Tokyo Intra-company group (72) Inventor Kazuya Miyano 2-5-8 Kita-aoyama, Minato-ku, Tokyo F-term (reference) 2D054 AC18 AD27 2D055 BA04 KA09 KA10 KB05 4G012 PA02 PB15 PB16 PB26 PB31 PB32 PB33 PB36 PC02 PC03 PC11 PE04 PE07 RA05

Claims (6)

[Claims] In a method of constructing a propulsion pipe for propelling and adding a propulsion pipe from a shaft while excavating a tunnel with an excavator, high-fluid concrete is poured into a vertical formwork on the ground near the shaft, and the propulsion pipe is constructed. On-site molding process, molding the propulsion tube horizontally in the on-site curing yard for curing, and a propulsion process for lowering the cured propulsion tube into the shaft and propelling it. Characteristic propulsion pipe construction method. 2. A method for constructing a propulsion pipe according to claim 1, wherein, in the on-site molding step, a grout hole which is also used as a suspension is simultaneously formed on the propulsion pipe. 3. A method for constructing a propulsion pipe according to claim 2, wherein, in the on-site molding step, a grout hole for rollover is simultaneously formed on the propulsion pipe. 4. The method for constructing a propulsion pipe according to claim 1, wherein the propulsion pipe is simultaneously molded with an internal component such as an invert portion and a partition wall in the in-situ molding step. 5. The high fluidity concrete to be used is a concrete containing a high-performance AE water reducing agent comprising a composite of a polycarboxylic acid ether and an intramolecularly crosslinked polymer. 4. The method for constructing a propulsion pipe according to 4. 6. The method according to claim 5, wherein the high-fluidity concrete has the following composition. Unit water amount: 155 to 175 kg / m ³ unit Cement amount: 450 to 600 kg / m ³ unit fine aggregate amount: 780 to 910 kg / m ³ (specific gravity 2.6
Case) unit coarse aggregate amount: 810 to 945 Kg / m ³ (specific gravity 2.7)
Case) High-performance AE water reducing agent: 0.5 to 2.5% based on water