JPS6078100A - Re-embedding method of pit - 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 The present invention relates to a method for backfilling a used tunnel, such as an investigation shaft or an abandoned mine, to completely block it.

Conventionally, when backfilling used survey shafts, tunnels, tunnels, etc., the backfilling soil may flow out due to spring water, etc., or the inside may cave in or sink due to incomplete filling of backfilling material. In order to prevent this from happening, a method has been used in which the interior is poured and filled with concrete, and after it hardens, mortar or the like is poured into the void zone created above.

However, with this conventional method, the filled concrete
Due to the shrinkage caused by the hardening of 1-, a void zone is created locally, which becomes a passageway for spring water and gas, causing ground subsidence and cave-ins, making it difficult to safely refill the blockage. there were. In addition, concrete poured into the inside of a tunnel etc. requires a considerable amount of time to harden, and furthermore, the re-pouring of mortar, cement milk, etc. is required twice, which prolongs the construction time. Therefore, there was a problem in that it led to high costs.

This invention was made to solve the above problems, and its purpose is to lay a drain pipe at the bottom of the mine shaft, and collect spring water in the surrounding ground at each important point of this pipe. In addition to taking measures to drain the water and introducing it into the drainage pipe, concrete, etc. made of a low water-cement ratio, which shrinks less during hardening, will be sequentially installed on vertical surfaces starting from the innermost U15 (face part) of the tunnel. By spraying and filling in layers, the process is completed uniformly and quickly without the formation of local void zones that can cause ground subsidence or cave-ins, using a simple construction method that does not require much effort. The object of the present invention is to provide a method for backfilling a tunnel, which enables complete filling in a timely manner, thereby achieving safe closure and significant cost reduction.

Hereinafter, this invention will be explained based on the drawings.

As shown in FIGS. 1 and 2, the face IA in the tunnel 1 is the target of backfilling according to the present invention.

If there are sheet piles or the like in use on the peripheral walls of the intermediate part IB and the mine entrance part 1C, these shall be removed when the mine is abandoned or immediately before backfilling.

Along both sides of the bottom of the existing tunnel 1 according to the above aspect, a third
As shown in the figure and FIG. 4, a drain pipe 2 is installed to collect spring water in the Niki tunnel 1 and drain it to the outside. In this case, valves 3 are temporarily inserted into the drain pipe 2 at an intermediate position thereof and at a position close to the tunnel entrance t+l+tc in the tunnel l. In addition, drain poling holes 4 are provided at positions where there is a possibility of spring water in the tunnel l and at predetermined intervals in the ground on the outer periphery through the peripheral wall surface thereof to collect spring water around the ground. The distal end of a strainer pipe 5 made of a material rich in filterability is inserted into this drain poling hole 4, and its base end is connected to the drain pipe 2 laid at the bottom of the mine at this location. 1. Spring water from the drain poling hole 4 is introduced into the drain pipe 2 through the strainer pipe 5 without being stored, and is actively drained outside the mine.

After taking the above drainage measures, as shown in Figure 3,
Concrete 7 is fed through a spray nozzle 6 from the surface of the face IA, which is located at the innermost part G in the tunnel 1, and is sequentially sprayed to create a layered structure on the vertical surface while retreating toward the mine entrance IC. Concrete 1 kidney is formed by this, and the tunnel 1
The inside is filled with concrete 7. At this time, spring water and gas generated within the tunnel 1 are discharged outside the mine through the drainage pipe 2, so that adhesion of the concrete 7 to the inner wall surface of the tunnel I and inhibition of hardening can be prevented.

The concrete 7 used above has a low water-to-cement ratio that exhibits a small amount of shrinkage during hardening. Therefore, it becomes possible to uniformly spray the concrete in layers along the vertical plane, and thereby the entire area inside the tunnel 1 can be completely connected by the filled layer of concrete 7.

In this case, the filling of concrete 1 and 7 is done by the spraying method, so for example, the water-cement ratio W/C is 40 to 45.
The amount of shrinkage during curing can be extremely reduced. Also, spray Non-Clean 1-7 in a vertical layer along the vertical surface (;J construction, so
It is possible to actually prevent the formation of local void zones in the second part of the tunnel 1 after hardening.Furthermore, since it is a one-step process called spraying, Most of the time, it's just a setup change of the construction machinery (it's possible to perform backfilling work with high efficiency.

” - Since the drain pipe 2 has a knob 3 installed at its intermediate position and at a position close to the mine entrance IC in the tunnel 1, the concrete 1 and 7 surrounding the water collection part of the drain pipe 2 are installed. When the water has hardened to the required strength, the valve 3 at that position is closed, and the water drain pipe 2 is removed.
The drainage pipe 2 is separated into concrete parts 1 and 2.
- I will bury it in 7.

In the above embodiment, if there is a sheet pile in use on the peripheral wall surface of the tunnel 1, which is one example of backfilling, it is assumed that this will be removed when the mine is abandoned or immediately before backfilling. This invention is not limited to the above-mentioned embodiments, but is applicable to cases where the peripheral wall surface is formed of concrete or metal materials such as a driveway and is difficult to remove, or when sheet piles are in use. If removing it would impede the construction of backfilling the inside of the tunnel I, backfilling can be performed without removing it. If the zunawaji is not to be removed, a hole is drilled through the surrounding wall member surface (the above-mentioned concrete IJ-1-, metal material, sheet pile, etc.),
A drain poling hole 4 similar to the above embodiment is provided in the ground on the outer periphery communicating with this hole, and this drain poring hole 4 is provided.
By installing the strainer pipe 5 between the drain pipe 2 and the drain pipe 2 at the bottom of the tunnel 1, as in the previous embodiment,
It can be reclaimed while draining.

Further, in the above embodiment, concrete 7 with a low water-cement ratio, which has a small amount of shrinkage upon hardening, was used as the filling material in the tunnel 1. However, the present invention is not limited to the above embodiment, and can be Even if a hydraulic material prepared by mixing ash, FA crushed slag slag, gravel, sand, lime, gypsum, various types of cement, etc. in appropriate ratios and adding water is used as the filler, the result is the same as in the above example. In addition, the inside of the tunnel can be easily refilled with a completely packed bed.

As explained in Section 2 below, this invention involves laying a drainage pipe at the bottom of the tunnel, and at each key point of this pipe there is a drainage means for collecting spring water in the surrounding ground and introducing it into the above-mentioned aquatic pipe. At the same time, starting from the innermost part (face) of the tunnel, the above-mentioned concrete is filled by spraying concrete, etc. with a low water-cement ratio, which shrinks less during hardening, in vertical layers. Since no void zone is formed on the circumferential wall surface of the mine, it is possible to easily and reliably prevent the pit from sinking or sinking due to this void zone. In addition, since it is only possible to fill a completely filled state by spraying vertically in layers, even if a structure is built outside the upper layer of this mine, there is no fear of the ground sinking or subsidence, and the structure will remain permanent. safety can be ensured. In this way, the method of this invention uses a single construction method that does not require one-time effort, eliminates the generation of local void zones that can cause ground subsidence or depression, and can be applied uniformly and in a short time. Complete filling is possible, resulting in safe blockage and significant cost savings for backfilling the tunnel! This has the effect of reducing the amount of land used, opening up ways to reuse land in Japan, a country with a small land area.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view of the main parts of the tunnel immediately before the tunnel backfilling according to the present invention, FIG. 2 is a front view of the same, and FIG. 3 is a cross-sectional plan view showing the tunnel backfilling method according to the present invention. , FIG. 4 is a longitudinal sectional front view showing the inside of the tunnel just before the start of the same backfilling method, and FIG. 5 is a longitudinal front view of the shaft completely blocked by the same backfilling method. 1... Mine shaft 2... Water drain pipe 3... Valve 4... Water drain poling hole 5... Strainer pipe

Claims (1)

[Claims] A drain pipe is laid along the bottom of the tunnel, a drain poling hole is provided in the peripheral wall of the tunnel that penetrates into the ground around the outer periphery, and this drain poling hole is connected to the drain pipe via a drain pipe. At the same time, while draining the spring water in and around the tunnel using the drainage pipe, 1): The filling phase is sequentially sprayed in layers on the vertical plane from the end face at the back of the tunnel to the mouth. J. A method for backfilling a tunnel, characterized by filling and closing a tunnel space.