JPS5894599A - Soil pressure type shield drilling method using water soluble high molecular substance - 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 Tonosho-based shield construction method for excavating a tunnel using a water-soluble polymer or the like.

The shield construction method is often used in the construction of subways, underground tunnels, sewers, etc. because it has less impact on road traffic and construction pollution on nearby residents due to tunnel construction. The Nagade Tonosho shield construction method generally involves filling a cutter drum with earth and sand cut from the face using a cutter to prevent the face from collapsing, and transporting the earth and sand using a screw conveyor, etc., and then assembling segments to construct a tunnel. However, compared to the pressurized air shield method, it has the advantage of providing a better working environment and does not require any auxiliary methods.In addition, compared to the muddy water pressurized shield method, it requires soil separation equipment and muddy water treatment equipment. There are advantages such as not having to

However, with the conventional Tonosho shield method, when excavating the Tonosho face, depending on the soil quality of the excavated soil, arching of the earth and sand may occur inside the cutter drum, or earth and sand may adhere to the cutter drum, increasing cutting resistance against the face. Furthermore, in areas with abundant groundwater, a large amount of ground water is drawn in, often making it impossible to excavate.

The present invention has been made to solve the above problems,
The purpose is to provide a Tonosho-based shield excavation method that can efficiently excavate tunnels (without increasing the cutting resistance against the face due to the soil quality of the excavated soil, and without drawing in large amounts of water from the ground). There is a particular thing.

Embodiments of the present invention will be described below with reference to the drawings.

1 is a Tonosho type shield excavator, and ko is a cutter drum installed in the front part of the excavator 1. The cutter drum is supported by a seal 3 and a rotary table bearing, and is rotationally driven by a drive motor 6 via a transmission mechanism S. The cutter drum is pivoted at the rear to a bulkhead fixed to the shield skin plate side. 9 is a screw conveyor. The tip opening of the screw conveyor/'OQ
It is inserted into the cutter drum by passing through the partition wall. // is a scooping plate for scooping up excavated earth and sand, and is fixedly installed at appropriate intervals on the peripheral wall surface of the cutter drumco. The face A of the cutter 7 on the front of the cutter drum 2
A plurality of injection nozzles/3 are provided toward the. The injection nozzle 13 is communicated with the supply pipe 7 via a branch pipe 15S and an intermediate pipe 15S swivel joint 1A. A plurality of injection nozzles ig are provided on the partition wall g toward the interior of the cutter drum, and are connected to the supply vibe/9.

20 is segment, 2/ is shield propulsion jack 1.2
2 is a soil discharge port, =23.2'I is a valve.

Next, the operation according to the present invention will be explained according to the drawings.

The Tonosho-type shield tunneling machine 1 receives a reaction force from the segment 2'Q assembled at the rear of the tunneling machine, and is propelled toward the face A side by the shield propulsion jack, one end of which is fixed to the tunneling machine 1. . Then, the earth and sand excavated from the cutting WA is taken into the cutter drum by the cutter face 1.2 on the front surface of the rotatably driven cutter drum.

On the other hand, a supply pump (not shown) supplies water-soluble polymer and oil to the jet nozzle 13 toward the face A, and from the jet nozzle/g to the excavated soil taken into the cutter drum. A mixture of is injected. Here, in the mixture of water-soluble polymer and oil according to the present invention, the water-soluble polymer is CM (1!), methyl cellulose, polyacrylamide, sodium polyacrylate, polyethylene oxide, polyvinyl alcohol, etc. alone. , or a mixture of two or more, which has the function of absorbing excess water in excavated soil and plasticizing the excavated soil, and the oil is preferably a fluid but non-volatile oil, such as soybean oil, cottonseed oil, Machine oil and the like function as a dispersant for the water-soluble polymer and as an aid for uniformly mixing the water-soluble polymer into the excavated soil.

In this way, when the water-soluble polymer/oil mixture is injected into the excavated soil taken into the face A and the cutter drum 2, the cutting resistance during mechanical excavation of the face A does not increase, and the cutting force of the face A is reduced. While maintaining stability, the excavated soil containing a large amount of water taken into the force/jitter drum a is stirred and mixed with the water-soluble polymer/oil mixture by the rake plate of the rotating cutter drum, and becomes plastic. and moves to the tip opening /θ of the screw conveyor.

At this time, the fluidized and plasticized excavated soil is conveyed into the screw conveyor without causing any arching or adhesion within the cutter drum. After that, the excavated soil is removed from the soil discharge port 2.
- and then transported out of the mine by means of discharging means (not shown) such as a belt conveyor or trolley.

That is, the water-soluble polymer/oil mixture according to the present invention aims to reduce the cutting resistance during mechanical cutting of the face A5,
It also absorbs a large amount of excess water in the excavated soil taken into the cutter drum, plasticizes the excavated soil, and improves the fluidity of the plasticized excavated soil.

According to the present invention, since a mixture of a water-soluble polymer and oil is injected into the excavated soil containing a large amount of surplus water taken into the face and cutter drum, the cutting resistance during mechanical excavation of the face is reduced. At the same time, it absorbs a large amount of excess water from the excavated soil taken into the cutter drum.
Since the excavated soil is made plastic, it is possible to prevent the occurrence of arching and adhesion of the excavated soil inside the cutter drum.Furthermore, the fluidity of the plasticized excavated soil is improved, so that the excavated soil flows smoothly inside the screw conveyor. At the same time, it is possible to prevent the excavated earth from blowing out due to water pressure at the earth and sand discharge port of the screw conveyor.

[Brief explanation of the drawing]

FIG. 11 is a longitudinal cross-sectional view of the Tonosho shield tunneling machine according to the present invention. L: Tonosho type shield excavator Konikatsuta drum g, bulkhead desk screw conveyor 13.7g: Injection nozzle A: Face Patent applicant Opai Co., Ltd.

Claims (1)

[Claims] In the Tonosho shield drilling method, a mixture of water-soluble polymer and oil is injected into the face and cutter drum.
A Tonosho shield excavation method that uses water-soluble polymers to excavate tunnels.