JPS5911007B2 - Construction method for water intakes and water outlets in waterway tunnels in underground ground - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION When constructing a large-scale intake or outlet for water in a waterway tunnel in the underwater ground in a rocky area at a depth of 35 yn or more, where diving is generally difficult, this has not been done in many cases. In this method, a tunnel is dug deep beneath the waterbed, and a vertical shaft for the water intake and water outlet is constructed using the caisson method or the Tsukishima method.

However, all of the conventional construction methods described above require large-scale construction, are difficult to perform air pressure work and water shutoff work, and have the disadvantage of prolonging the construction period and increasing construction costs.

The present invention was proposed in view of the above-mentioned circumstances, and involves penetrating steel pipes to a predetermined depth in the underwater ground at each required location to form a shaft made of steel pipes, and then draining the water inside each steel pipe. , Next, a horizontal shaft is excavated into the underwater ground below each of the steel pipe shafts, and the horizontal shaft is communicated with each of the steel pipe shafts.Construction of water intake and water outlet in a waterway tunnel in the underwater ground, characterized by: Regarding the construction method, its purpose is:
The work is easy and does not require diving, the work is carried out in a space without spring water until the final stage of construction, and work in pressurized air is not required as in submersible work, and water supply in canal tunnels in the underwater ground is easy. The purpose is to provide an improved construction method for constructing large-scale, perforated water intakes and water outlets.

In the present invention, after penetrating the steel pipe to the required depth of the underwater ground, the inside of the steel pipe is drained to construct a shaft. Therefore, the construction of the shaft is easy and is less dependent on the water depth. Since the constructed steel pipe shaft was connected to the horizontal shaft dug through the underwater ground,
Since the construction work is carried out in a space without spring water from the start to the completion, and there is no diving or submersible work, there is no need for special workers, and therefore it is easy to use a large-scale porous system for irrigation water in waterway tunnels in the underwater ground. Water intake and water outlet will be constructed.

Furthermore, according to the present invention, several or even dozens of shafts can be constructed so as to obtain the required cross-sectional area, so there is no need for a super-dog-shaped shaft. It has advantages.

The present invention will be described below with reference to the illustrated embodiments.

First, a vertical hole 2 reaching a predetermined depth in the underwater ground 1 is excavated at the location of the water intake and water outlet in the waterway tunnel in the underwater ground, and a steel pipe 3 is inserted into the vertical hole 2.

An upper steel pipe 3' is connected to the steel pipe 3 by bolts 4 or the like so that it can be attached and detached at desired positions.

(See FIG. 1) Next, the gap between the steel pipe 3 and the vertical hole 2 is filled with mortar 5, and after the mortar 5 has hardened (see FIG. 2), the water in the steel pipe 3 is drained.

(See Figure 3) In this state, several spring water detection holes are drilled in the portion of the steel pipe 3 in the water bottom ground 1 to check for the presence of spring water.

If there is spring water, use this detection hole or apply mortar grout from the outside of the steel pipe 3 to stop the water.
In this way, a space without spring water is formed within the steel pipe 3 serving as the shaft.

After constructing the above-described steel pipe shafts, horizontal shafts 6 for water intake tunnels and water discharge tunnels are excavated in the underwater ground 1, and the steel pipe shafts and horizontal shafts 6 are communicated with each other.

(See Figure 4) At this time, the horizontal shaft 6 is excavated by the steel pipe 3 of the vertical shaft.
Since it has been confirmed that there is no spring water by insertion and grout water stop, construction can be carried out in a space without spring water.

After the steel pipe shaft and the horizontal shaft 6 are connected as described above,
Using the steel pipe 3 in the shaft, inject water until the water level inside the steel pipe 3 is the same as the water level outside, remove the bolt 4, remove the steel pipe 3' at the top of the joint, and open the manholes at the water intake and water supply ports. 7 to complete the entire process.

(See FIG. 5.) Although the present invention has been described above with reference to embodiments, the present invention is of course not limited to such embodiments, and various designs may be made without departing from the spirit of the present invention. It is possible to make the following modifications.

[Brief explanation of the drawing]

FIGS. 1 to 5 are longitudinal sectional views showing steps of an embodiment of the construction method for water intakes and water outlets according to the present invention. 1... Underwater ground, 2... Vertical shaft, 3...
...Steel pipe, 6...Horizontal pit.

Claims (1)

[Claims] 1. Piercing steel pipes to a predetermined depth in the underwater ground at each required location to form steel pipe shafts, then draining the water inside each steel pipe, and then digging horizontal shafts into the underwater ground below each of the steel pipe shafts. A method for constructing a water intake and a water outlet in a waterway tunnel in the underwater ground, characterized in that the horizontal shaft is communicated with each of the steel pipe shafts.