JPS61130596A - Construction method of tunnel wall surface - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a tunnel wall construction method for constructing wall concrete in a tunnel.

<Conventional technology> There are various spraying methods for constructing concrete walls in tunnels, etc.

For example, one method that is frequently used is the dry method, in which cement and aggregate are mixed and sprayed to the tip of a nozzle, where they are mixed with water and sprayed with compressed air.

Problems to be Solved by the Present Invention> The conventional construction methods described above have the following problems.

(b) The amount of concrete rebound is large (not economical).

(b) Since spraying requires a certain distance between the surface and the nozzle, it occupies the working area in tunnels and the like.

(c) It is difficult to carry out in parallel with other work, and the overall construction period becomes longer.

(d) Since the dry kneading material and water are mixed at the nozzle, the quality depends on the skill level of the worker.

(e) Spraying generates a lot of dust during work, worsens the working environment, and poses many problems in terms of occupational safety and health.

OBJECT OF THE INVENTION The present invention has been made to solve the above-mentioned problems.It suppresses the generation of dust to prevent deterioration of the working environment, does not occupy the working area, and does not require the use of other objects. The purpose of the present invention is to provide a method for constructing tunnel walls that can be performed in parallel with the work, increasing work efficiency, reducing bounce back, and being economical, as well as enabling construction of high-quality concrete walls. do.

<Means for Solving the Problems> In order to solve the above problems, the present invention employs the following means.

In other words, a guide rail is attached to the outer periphery of a support frame that is movable in the axial direction of the tunnel and has a cross-sectional shape that is almost similar to the cross-sectional shape of the tunnel, and the formwork is moved using formwork plates that apply pressure to the filled concrete while vibrating finely. The device moves along guide rails to fill concrete with low slump, and applies pressure while vibrating the concrete to construct a high-quality concrete wall.

<Example> Next, an example of the present invention will be described based on the drawings.
First, the wall concrete placing apparatus used in the present invention will be explained.

The wall concrete placing device used in the present invention includes a guide rail 1 that is movable in the axial direction of the tunnel and is attached to a support frame S that has a cross-sectional shape that is almost similar to the cross-sectional shape of the tunnel. It consists of a formwork moving device 2 that moves by moving the formwork.

(a) Support frame and guide rail The support frame S is a structure consisting of a front frame and a rear frame, and has a cross-sectional shape that is almost similar to the cross-sectional shape of the target tunnel.

Then, the kite rail 1 is attached to the outer periphery of the front frame of the support frame S on the advancing direction side.

The guide rail 1 is formed, for example, from a steel material having an H-shaped cross section into a shape along the outer periphery of the support frame S, and is attached to the front frame.

A guide rack 1 is provided on the guide rail 1 almost parallel to the inner wall of the tunnel over its entire length.

The guide rack 11 is a toothed plate with which a gear 21 of a formwork moving device 2 to be described later meshes.

Further, the support frame S is configured to be movable in the axial direction of the tunnel by, for example, laying rails in the axial direction near the wall surface of the floor surface of the tunnel.

Furthermore, a press-fitting cylinder S1 is installed at the top end of the rear frame located at the rear with respect to the direction in which the support frame S moves, and a steel sheet pile Y, which will be described later, is press-fitted between the guide rail 1 and the poured concrete. do.

(b) Formwork moving device (FIG. 2) The formwork moving device 2 is a rectangular plate body having a gear 21 on the side.

It is a member that moves along the guide rail 1 on the inner periphery of the tunnel by applying rotation to the gear 21 anastomosed with the guide rack 11 of the guide rail 1 using a built-in traveling device or the like.

The formwork moving device 2 is moved by locking the gear 21 to the guide rack 11.
A formwork plate 22 is installed on the tunnel inner wall side of the formwork moving device 2 while the formwork plate 22 is installed on the guide rail 1.

The form plate 22 is a rectangular plate parallel to the tunnel wall surface, and a flange 23 is provided on one side of the guide rail toward the wall surface to provide a space between the tunnel wall surface and the form plate 22 to be filled with concrete. Configure.

Further, a discharge port 24 for filling concrete between the form board 22 and the tunnel wall surface is provided in the form board 22, and a concrete vibe P from a concrete pump is connected thereto.

(C) Motion of the formwork plate A vibrator 25 that gives small vibrations to the formwork plate 22 is attached to the surface of the two examples of the formwork moving device of the formwork plate 22.
.

Further, jacks 26 from the formwork moving device 2 are connected to the upper and lower portions of the formwork moving device 2 side surface of the formwork plate 22.

By slowly expanding and contracting both, the form plate 22 is configured to reciprocate with a large stroke.

Next, a method of constructing a tunnel wall surface using each of the above devices will be explained.

(b) Installation of support frame First, a support frame S is installed inside the target tunnel.

That is, a rail for moving the support frame S is laid near the wall surface of the floor surface of the tunnel, and the support frame S to which the guide rail 1 is attached is placed on the front frame of the rail.

(b) Installation of a formwork moving device The formwork moving device 2 is installed at the bottom of one end of the guide rail 1 of the support frame S.

That is, the flange 23 of the form plate 22 is positioned on the excavation direction side of the tunnel wall surface, and the gear 21 of the form moving device 2 is locked to the rack 11 of the guide rail 1.

(c) Filling concrete and moving the form plate Concrete is discharged from the outlet 24 of the form plate 22 through the concrete pipe P, and concrete with a small slump is filled between the other pile and the form plate 22.

Then, in parallel with the shaping of the concrete, the formwork moving device 2 is slowly moved along the guide rail 1 to cast a band-shaped concrete wall around the inner periphery of the tunnel wall surface.

In addition, in the process of lowering the formwork plate 22, a frame is provided protrudingly below the formwork plate 22 to prevent concrete from falling.

At this time, it is also possible to install reinforcing bars, iron plates, etc., such as reinforcing materials for concrete walls, in advance in the area where concrete is to be poured.

(d) Operation of the formwork plate The formwork plate 22 starts a certain movement by the vibrator 25 and the jack 26 as the formwork moving device 2 moves.

That is, the form plate 22 repeats a large stroke reciprocating motion by slowly expanding and contracting the upper and lower jacks 26 while being slightly vibrated by the vibrator 25.

(Fig. 3) The reciprocating motion with a large stroke compacts the filled concrete, while the small vibration by the vibrator 25 makes the concrete dense.

The wave-like movement by the jack 26 has an extremely large stroke, and the movement by the vibrator 25 is extremely small, so the formwork plate 22 does not lose its function as a formwork.

(E) Since concrete with a small slump for press-fitting the steel sheet pile is used, spalling of the concrete can be prevented by adjusting the moving speed of the formwork moving device.

However, at the top end of the tunnel, etc., the steel sheet pile Y is press-fitted between the guide rail 1 and the poured concrete using a press-fitting cylinder S1 as necessary to prevent the concrete from peeling off and falling off.

(v) Movement of the guide rail (Fig. 4) After pouring concrete in a band shape around the inner circumference of the tunnel along the guide rail 1, move the guide rail 1 in the axial direction to form plate 2.
Move by a width of 2 and pour a concrete wall on the adjacent tunnel wall in the same manner.

The construction time can be halved by preparing two formwork moving devices 2 and moving them toward each other from both ends of the guide rail 1.

Can also be done.

(G) Other Examples In the above embodiments, the formwork moving device was moved by the meshing of the gear 22 of the formwork moving device 2 and the guide rack 11 of the guide rail 1. It is also conceivable to use a known mechanism such as.

<Effects of the Invention> Since the present invention has been described above, the following effects can be expected.

(a) It is economical because there is no rebound of concrete and material loss can be suppressed.

(b) Formwork moving devices, etc. are located between the guide rail along the inner circumference of the tunnel and the wall surface, so they do not occupy the inner space of the tunnel, and can be used for excavation, scraping, etc. It can be used as a space.

Therefore, it can be done in parallel with these works, shortening the construction period.

(c) While the formwork moving device is moving, the formwork plate makes large wave-like back and forth movements and small vibrations, so it is possible to cast a dense concrete wall of good quality.

(2) The work environment is good with little dust generated during work.

(e) Concrete can be poured by wet pumping, so the amount of concrete to be poured can be accurately determined and the time required for pouring can be shortened.

[Brief explanation of drawings]

Figure 1: Explanation of the construction method of the present invention Second factor: Explanation of the guide rail and formwork moving device used in the present invention Figure 3: Explanation of the operating state of the formwork plate Figure 4: Explanation of the device Illustration of movement

Claims (1)

[Claims] A guide rail is attached to the outer periphery of a support frame that is movable in the axial direction of the tunnel, and the formwork, which vibrates and moves back and forth at large cycles toward the pouring surface, is moved along the guide rail. A construction method for tunnel walls, characterized by pouring concrete at the same time.