JPS593633B2 - Soil type compatible shield excavator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a shield excavator suitable for soil type used for excavating extremely soft ground, and an object of the present invention is to provide a shield excavator that can always perform excavation work at an operating speed commensurate with the face properties. shall be.

Conventionally, a so-called Tonosho type shield excavator has been used for excavating soft ground.

As shown in FIG. 1, this shield tunneling machine has a shield tunneling machine main body 1 divided by a partition wall 2 into a pressure chamber 4 facing the earth 3 and an atmospheric pressure chamber 5 behind the pressure chamber 4. Excavation was carried out by a shield jack 6, excavation was carried out by a cutter γ, and excavated soil was discharged by a screw conveyor 8 arranged across the pressure chamber 4 side and the atmospheric pressure chamber 5 side of the partition wall 2. .

Earth and sand with a high moisture content excavated by the Sunaichi cutter 1 flows into the pressure chamber 4 at the rear of the cutter and fills the pressure chamber 4 to maintain an upper pressure on the ground 3 and prevent it from collapsing. are doing.

Of the earth and sand filling the pressure chamber 4, only the amount corresponding to the amount of excavation is sequentially discharged to the atmospheric pressure chamber 5 side by the screw conveyor 8.

In this case, the atmospheric side mud removal port 8 of the screw conveyor device 8
A gate valve device 9 is attached to a, and the opening degree of the gate device 9 is controlled to fill the inside of the screw conveyor device 8 with earth and sand while removing sludge and transferring it.

The amount of earth and sand flowing into the pressure chamber due to excavation and the amount of earth and sand discharged by the screw conveyor 8 are balanced so as to correspond to the properties of the face of the excavated ground.

Although conventional shield excavators have the basic configuration as described above, the actual properties of the ground are not uniform throughout the entire planned excavation area, and groundwater is usually present in the ground.

On the other hand, the screw conveyor 8 described above does not have water-stop properties, so when excavating in areas where groundwater exists, the gate device 9
When the mud draining port 8a is slightly opened, groundwater flows out like a waterfall, and only a small amount of earth and sand flows out after that, and when it is fully opened, it becomes difficult to hold the earth and sand, and the earth and sand are washed away.

In short, any shield excavator for soft ground must be provided with a dewatering process for the excavated soil.

The present invention is a shield excavator having the above-mentioned dewatering process, which can reliably grasp the properties of the excavated ground during excavation, and thereby automatically control appropriate excavation, excavation speed, sludge removal speed, and dewatering speed. An example of its implementation will be described below based on illustrative drawings.

In FIG. 2, 10 is an excavated earth 12 by a compartment 11.
The main body of the Truld excavator is divided into a pressure chamber 13 facing the pressure chamber 13 and an atmospheric pressure chamber 14 behind the pressure chamber 13.

A cutter 15 for excavation is arranged in the front part of the pressure chamber 13.
1 and is driven to rotate.

A screw conveyor 18 is provided across the pressure chamber 13 side and the atmospheric pressure chamber 14 side of the compartment 11.

A dewatering device 20 is connected to the mud discharge port 19 of the screw conveyor 18, and a soil outlet 2 of the dewatering device 20
1 is provided with an outlet valve 22.

Reference numeral 23 denotes a shield jack for excavation fixed to the shield excavator main body 10. During excavation, the shield jack 23 is first extended to move the shield excavator main body 10 forward, and the cutter 15 is rotated. Earth and sand are caused to flow into the pressure chamber 13, and at the same time, the screw conveyor 18 is driven to fill the outlet valve 22 with the earth and sand.

At this time, the dehydration device 20 does not perform the original dehydration action,
The P cloth 20a is only slightly rotated in accordance with the inflow speed of the earth and sand.

The above is the preparation before operation. Next, the drive motor 16 is activated to rotate the cutter 15 and start excavation.

Then, the P cloth 20a of the dewatering device 20 is moved slowly in accordance with the inflow speed of the earth and sand, and at the same time it is pressurized and dehydrated.
Furthermore, the dewatering device 20 is suctioned by the vacuum device 24 to continuously pressurize and dehydrate the earth and sand inside.

In this case, the soil inside the dewatering device 20 is dehydrated and its moisture content decreases, and at the soil outlet 22 it is subjected to compaction resistance by the biasing spring 25 of the outlet valve 22, so that the soil in the pressure chamber 13 is completely compressed. Retained.

The water dewatered in the dewatering device 20 is stored in the dewatering cart 21 through the drain pipe 26, and on the other hand, the dewatered soil 28 containing water stored in the dewatering cart 2γ is removed in an amount commensurate with the consolidation resistance. The soil passes between the open soil outlet 21 and the outlet valve 22 and is thrown into the waste truck 29.

After the water is stored in the dewatering cart 21, the amount of water is measured on the load cell 30, and the amount of soil is also measured.
It is measured by placing it on 0.

Reference numeral 31 denotes a calculation device that calculates the water content of the excavated ground from the measured values of the amount of water and the amount of soil, and a calculation signal from the calculation device 31 is input to the indicating device 32 .

Then, by this indicating device 32, the running speed of the furnace cloth 20a of the dehydrating device 20 is set to a speed commensurate with its moisture content, that is, the water content (for example, if the moisture content is high, the amount of water removed will be large, so the furnace cloth traveling speed will be slow). ), and the cutter 1
5, the rotation speed of the drive motor 16, the rotation speed of the drive motor 18a of the screw conveyor 18, the extension amount and extension pressure of the shield jack 23,
(For example, if the furnace cloth traveling speed becomes slower, the operating speed and capacity of each device will be reduced.)

Therefore, if the moisture content of the ground changes during excavation, the operating speed of each of the above-mentioned devices will be controlled in the most appropriate manner to follow it, making it possible to excavate in a semi-automatic or nearly fully automatic state.

As is clear from the above explanation, the present invention calculates the moisture content of the excavated earth based on the amount of water dehydrated from the excavated earth and the amount of earth and sand, and based on this calculated value, the furnace cloth movement speed of the dewatering equipment and the earth and sand outflow. In addition to controlling the relative speed to zero, each operation speed, such as cutter rotation speed, screw conveyor transfer speed, shield jack extension amount, and extension speed, is controlled to be the most appropriate for the soil moisture content. The earth pressure for maintaining the face surface is reliably maintained by the consolidated earth and sand in the dewatering equipment.
We can provide a soil type shield excavator that guarantees safe work.

[Brief explanation of drawings]

FIG. 1 is a vertical side view showing a basic conventional shield tunneling machine, and FIG. 2 is a vertical side view of a soil type compatible shield tunneling machine according to an embodiment of the present invention.

Claims (1)

[Claims] 1. It has a partition wall that divides the main body of the shield excavation machine into a pressure chamber facing the excavated ground and an atmospheric pressure chamber behind the pressure chamber,
A shield excavator that holds the face of the rock by the earth pressure of excavated earth and sand filled in the pressure chamber, and is arranged between a pressure chamber side and an atmospheric pressure chamber side of the partition wall, and It comprises a screw conveyor that is filled with excavated earth and sand and transports the earth and sand, a dewatering arrangement connected to the conveyor outlet, and a shield jack that excavates the main body, and is separated by the dewatering apparatus. A measuring device is provided to measure the amount of soil and the amount of dewatered water, and a calculation device is provided to calculate the moisture content of the excavated ground from these measured values, and the operating speed of the dewatering device is calculated by the calculation device. The operating speed of the rock excavation cutter drive device, the screw conveyor drive device, and the shield jack is set to a speed commensurate with the dewatering device. A shield excavator adapted to soil type, characterized in that it is equipped with an instruction device that instructs the user to do so.