JPH01299998A - Shielded propulsion and shielding construction method in lining on-site lining - Google Patents

Abstract

PURPOSE:To enable the easy assembly of a reinforcement member at the predetermined position by assembling the member with the shield propulsion jack forward part inserted into the steel pipe of a reinforcement for concrete. CONSTITUTION:A reinforcement member 1 to be assembled in a shielding machine is constituted with a steel pipe 2 and a reinforcement 3, and divided into a plural number in a circumferential direction. The forward part of a propulsion jack is inserted in the steel pipe 2 of the reinforcement 1 and the reinforcement member 1 is assembled in turn in a circumferential direction. Then, an inner mold frame 4 is assembled on the internal surface of the reinforcement member 1 and a tail frame 6 is used to close a gap at the side of the shielding machine between the drum plate of thereof and the inner mold frame 4. In addition, concrete is filled into the aforesaid gap. Thereafter, quick- curing mortar filled in the steel pipe 2 of the reinforcement member 1 is pressed with the propulsion jack, thereby enabling a shielded drilling and advancing process. Furthermore, after the completion of drilling, the forward part of the propulsion jack is drawn in turn from the inside of the steel pipe 2 and quick- curing mortar is instead filled into the steel pipe 2 in order.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a propulsion method and a lining method for forming a tunnel lining with cast-in-place concrete without using ready-made segments.

(Prior technology) When lining a tunnel excavated by a shield machine, a method for lining the tunnel in a rational manner instead of assembling ready-made segments on-site and lining the tunnel is to assemble reinforcing bars and formwork inside the shield machine. Various methods have been proposed for assembling and pouring concrete.Categorizing them based on the method of obtaining the propulsion reaction force of the shield machine, there are two methods:
For example, see Japanese Unexamined Patent Publication No. 62-21999) and a method of taking it from a steel formwork (for example, see Japanese Unexamined Patent Publications No. 60-141998 and Unexamined Japanese Patent Application No. 62-194399).

[Problem to be solved by the invention]

In the conventional method of obtaining the propulsion reaction force from the bush rod, the propulsion reaction force can be obtained from the sufficiently hardened lining concrete via the bush rod buried in cast-in-place concrete, but since the concrete is hardened, It is not possible to pressurize the concrete and fill the tail void with concrete, and the waiting time for hardening is long, making it impossible to obtain the required excavation efficiency.Furthermore, the bushing rod that can withstand the propulsion reaction force is thick and heavy. For,
The equipment required for installation was large-scale, the time required for installation was long, and the workability was extremely poor.

In addition, in the method of taking the propulsion reaction force from the formwork, it is possible to compress cast-in-place concrete and fill the tail void with concrete.

However, in order to obtain a formwork that can withstand the concrete pressurized load and obtain sufficient propulsion reaction force, the formwork must have sufficient strength, which results in the formwork being heavy and difficult to handle. It became complicated. Since the propulsion reaction force in this method is obtained from the g-bar due to the adhesion between the concrete and the formwork, sufficient adhesion force is required even after the time when the mold can be removed, so the installation length of the formwork becomes long. The formwork transfer device for reusing the formwork is also large-scale, resulting in problems such as restricted work space and poor workability on curved sections.

Furthermore, in the conventional lining of this type of tunnel, reinforcing bars or steel frames are generally used as reinforcing materials for the concrete, but the work of assembling the reinforcing bars or steel frames in the narrow face of the tunnel is extremely complicated. This made it difficult to ensure the accuracy of reinforcing bar positioning and to arrange the reinforcing bars between rings in the tunnel axis direction.

In view of the above, the present invention eliminates the need for an excessively large inner formwork, makes the reinforcing member lightweight, simplifies the labor involved in its construction, is cost-effective, and has excellent workability. The purpose is to provide shield propulsion and lining construction methods.

[Means to solve the problem]

In order to solve the above problems, the present invention provides a shield propulsion and lining construction method in which cast-in-place concrete is formed by splicing a predetermined length at a time on the pouring surface, and the reinforcing member assembled in the shield machine is composed of steel pipes and reinforcing bars. The front part of the propulsion jack is inserted into the steel pipe, and reinforcing members are sequentially assembled in the circumferential direction.The inner form is assembled on the inner surface of the reinforcing member, and the shield machine body plate and the inner form are assembled. The side of the gap created between the shield machine and the frame is closed with a gable frame, concrete is poured into this gap, and after the concrete placement is completed, the reinforcing material filled in after the previous excavation is quickly hardened inside the steel pipe. The shield excavation is carried out by pressing the mortar with a propulsion jack, and after completion of excavation, the forward part of the propulsion jack is sequentially pulled out from inside the steel pipe of the reinforcing member, and the steel pipe is sequentially filled with quick-hardening mortar.

[Effect]

The functions and effects of the shield propulsion and lining construction methods in the cast-in-place lining constructed as described above are as follows.

As the front part of the shield propulsion jack is inserted into the steel pipe of the concrete reinforcing member, assembly is easy, and the reinforcing member can always be assembled in a predetermined position.

Since the propulsive reaction force is transmitted to the fast-hardening mortar inside the steel pipe, the propulsive reaction force does not act directly on the steel pipe, so it can be made thin and light, and the propulsive reaction force can be secured without affecting the already poured concrete. , excavates by extending the propulsion jack.

Tail voids that occur during shield excavation are filled with fluidized concrete by pressurizing the gable frame.

Note that since shoring is installed on the inner surface of the inner formwork, the concrete pressurization load applied to the inner formwork is borne by the shoring.

As described above, since concrete pressurization load and propulsion reaction force do not act on the inner formwork, the weight of the inner formwork can be reduced.

〔Example〕

Figure 1 is a cross-sectional view showing the reinforcing member, inner formwork, and support assembled in the tunnel, Figure 2 (a) is an explanatory diagram of how the reinforcing member is assembled, and Figure 2 (b) is the end frame installed. Fig. 2 is a sectional view showing the jacked up state and the jack arrangement.
C) is a diagram cut along the A-A line of Figure 2 (b), and Figure 2 (
d) is a diagram obtained by cutting FIG. 2(b) along the line B-B, and FIG.
a) to (d) are explanatory diagrams showing the construction order.

In FIG. 1, 1 is a reinforcing member assembled in the circumferential direction, and 2.3 is a steel pipe and a reinforcing bar that constitute the reinforcing member 1, respectively. An inner formwork 4 is assembled inside the reinforcing member l assembled in the circumferential direction. 5 is the inner formwork 4
It is a support built inscribed in the. 6 is the tail frame of the shield machine copper plate.

In Fig. 2(a), reinforcing bars 3 are assembled in a rectangular shape parallel to the steel pipe 2 at appropriate intervals, and an appropriate number are assembled in the circumferential direction at positions orthogonal to the steel pipe 2, and divided into several blocks. It is configured. 7 is a propulsion jack front part, and this propulsion jack front part 7 is inserted into the steel pipe 2 to assemble the reinforcing member.

In FIGS. 2(b) to 2(d), reference numeral 8 indicates the end frame, 9 indicates a through hole for the propulsion jack main rod and the steel pipe 2, and 10 indicates the installation position of the end frame jack. Reference numeral 11 denotes a seal on the outer periphery of the gable frame between the tail frame 6 and the gable frame 8, and numeral 12 represents an inner circumferential seal on the gable frame between the gable frame 8 and the inner form 4.

In FIG. 2(C), 13 is a propulsion jack main rod, and 14 is a steel pipe seal that seals the gap between the end frame 8 and the steel pipe 2.

In FIG. 2(d), 18 is the end frame jack, and 19 is the end frame jack rod.

Next, the construction order will be explained based on FIGS. 3(a) to 3(d).

■Assembling reinforcing bars and inner formwork, and filling quick-hardening mortar into steel pipes.

Quick-hardening mortar is filled into the steel pipe C of the reinforcing member embedded in the previously excavated part. Wife frame Jyatsuki 18 is reduced to wife frame 8
At the place where the excavation is completed, the reinforcing member 1 divided into several parts in the circumferential direction is carried by the assembly erector 15, and the forward part 7 of the propulsion jack is inserted into the steel pipe 2 for reinforcement. Hold member l and repeat this to assemble the reinforcing member into a circumferential ring. After that, the inner formwork 4 is placed inside the reinforcing member 1.
Assemble using the assembly erector 15. (Figure 3(a)
) Note that the reinforcing bars may be joined together by welding, wrapping, etc., and the joining method is not particularly limited.

■ Assembling the inner formwork support and setting the gable frame The support 5, which moves on the sliding beam (not shown) installed in the shield excavator that was used during the previous concrete pouring, is pulled in with a jack etc. The formwork 4 is supported. Further, the end frame 8 is set on the shield machine side surface in the gap formed between the inner formwork 4 and the tail frame 6. (See Figure 3 (b)) ■Concrete pouring and inner formwork demolding work Place fluidized concrete through a suitable injection hole provided in the inner formwork. Then, the inner formwork 4 at the location E, where the concrete has secured enough strength to withstand the pressure of the ground at the already lined location, is removed from the formwork circumferential erector 17 installed on the trolley 16.
Remove the mold by This removed inner formwork will be used as the inner formwork for the next excavation location. (See Figure 3 (c)) ■ Excavation and propulsion work At this point, the quick-hardening mortar filled in the steel pipe C assembled in the excavation part last time has a predetermined strength, so the propulsion reaction force is reduced by this. It can be taken from a continuous column of quick-hardening mortar in the steel pipe 2 that is continuously formed in the axial direction of the tunnel. Therefore, the propulsion jack main rod 13 is extended by pressing the forward part 7 of the propulsion jack against the quick-hardening mortar filled in the previously assembled steel pipe, thereby digging. (
(See Fig. 3(d)) At the end frame jack installation position 10 shown in Fig. 2(b), the end frame jack rod 19 is connected to the shield machine body by a hinge (not shown) as shown in Fig. 2(d). Extend the end frame jack 18 connected to the end frame jack 18 (see Fig. 3).
(see C)), the shield is propelled while pressurizing the end frame 8 and filling the tail void with concrete.

After the excavation and propulsion are completed, the main rod 13 of the propulsion jack 20 and the propulsion jack front portion 7 at the locations to be filled with quick-hardening mortar are sequentially reduced, and the inside of the steel pipe C is filled with quick-hardening mortar. (See FIG. 3(a)) The gable jack 18 is reduced in size after the poured concrete has developed enough strength to allow the gable to be removed from the gable. Repeat the above steps.

The propulsion jack 20 is composed of a main rod 13 and a front part 7, and the front part 7 is structured to fit into the inner diameter of the main rod 13, so that each can extend and contract independently.

(Effects of the Invention) l) A concrete reinforcing member can be assembled by sequentially inserting the forward end of the propulsion jack into a steel pipe, and the reinforcing member can be assembled efficiently without having to worry about positioning the reinforcing member.

2) The propulsion reaction force of the shield presses the fast-hardening mortar filled in the steel pipe of the reinforcing member, and as the propulsive reaction force does not act directly on the steel pipe and inner formwork, it is necessary to increase the strength of the steel pipe and inner formwork. This eliminates the need for weight loss and improves handling efficiency.

3) The propulsion reaction force of the shield is obtained by the fast-hardening mortar inside the steel pipe, so the frictional force caused by adhesion between the inner formwork and poured concrete is not required, so the installation length of the inner formwork can be shortened.
It is possible to reduce the number of required formwork and improve the workability of curved sections.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing the reinforcing member, inner formwork, and support assembled in the tunnel, Figure 2 (a) is an explanatory diagram of how the reinforcing member is assembled, and Figure 2 (b) is the end frame installed. Fig. 2 is a sectional view showing the fixed state and the rigid arrangement.
c) is a diagram cut along the A-A line of Figure 2(b), and Figure 2(
d) is a diagram obtained by cutting FIG. 2(b) along the line B-B, and FIG.
a) to (d) are explanatory diagrams showing the construction order. 1. Reinforcement member, 2. Steel pipe, 3. Rebar, 4. Inner formwork, 5. Support, 6. Tail frame, 7. Propulsion jack front part, 8. End frame, 9.・Through hole, IO・・End frame jack, 11・・End frame outer circumference seal, 12・・End frame inner circumference seal, 13・・Propulsion jack main rod, 14・・
・Seal for steel pipe, 15・・Erector for assembly 116・・
Dolly, 17... Form removal frame periphery erector 118... End frame jack, 19... End frame jack rod, 20... Propulsion jack, 5) a) Summary (b) Figure 3 (C) (d) 餘i

Claims (1)

[Claims] In the shield propulsion and lining method in which cast-in-place concrete is formed by splicing predetermined lengths at the joint surface, the reinforcing members assembled in the shield machine are composed of steel pipes and reinforcing bars, and are The front part of the propulsion jack is inserted into the steel pipe, and reinforcing members are sequentially assembled in the circumferential direction.The inner formwork is assembled on the inner surface of the reinforcing member, and the structure is formed between the shield machine body plate and the inner formwork. The surface of the gap facing the shield machine is closed with a gable frame, concrete is poured into this gap, and after the concrete placement is completed, the quick-hardening mortar inside the reinforcing steel pipe that was filled after the previous excavation was completed is pressed by a propulsion jack. shield propulsion in cast-in-place lining, which is characterized in that the shield is excavated, and after the excavation is completed, the forward part of the propulsion jack is sequentially pulled out from within the steel pipe of the reinforcing member, and the steel pipe is sequentially filled with quick-hardening mortar. , lining method.