JPH11223084A - Mud solidification facilities - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide mud solidification facilities which requires no large equipment nor large site area and further requires no full-time operator for confirming the quality of treated soil when restarting the operation after sudden or periodic stop of operation. SOLUTION: Soil excavated by a shield machine 7 from a facing is temporarily stored inside a storage tank through a mud conveying pipe 10 by a force feed pump 9 and then is carried to mud solidification facilities and equipments, 1 by a conveying pump 3 and is stirred and mixed with a solidifying agent and auxiliary materials poured by a solidifying material pouring device. Then, the amount of supply per unit time of mud placed in the mud solidification equipment 1 by the conveying pump 3 is made smaller than the amount of supply per unit time of mud supplied to the storage tank 2 through the mud conveying pump 3, and the mud solidification equipment 1 is operated continuously even while the shield machine 7 is stopped for assembling the pressure- protective panels to a tunnel wall.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to excavated earth and sand having a high moisture content formed by excavation of a shield excavator which is excavated while repeatedly intermittently assembling a pressure stop plate for preventing collapse of a wall surface of a tunnel. It belongs to the technical field of a mud solidification treatment equipment equipped with a mud solidification treatment device for metamorphic treatment to low-grade earth and sand.

[0002]

2. Description of the Related Art In the burial of water and sewer pipes and electric / communication wirings in urban areas, shield construction methods are often used to prevent traffic obstacles and various construction pollutions. The shield method has a unique problem that the excavated earth and sand excavated in the ground must be discharged outside the pit. Then, the efficiency of the excavated earth and sand is determined so as to influence the work efficiency of the entire construction. Therefore,
A number of construction methods have been developed and proposed to efficiently discharge excavated earth and sand, but the muddy water shield method and the earth pressure shield method are often used because of their good work efficiency.

[0003] In the earth pressure shield method, excavated earth and sand carried on the ground have a high water content because they are mixed with groundwater. Therefore, not only is the soil with high moisture content inconvenient to handle and transport on the ground, but also is not treated as reusable general soil. When a large amount of excavated soil with a high moisture content is discharged, it is difficult to secure a treatment plant for discarding the excavated earth and sand. Therefore, proposals have been made to reduce the water content of the earth and sand having such a high moisture content. For example, Japanese Unexamined Patent Publication No. Hei 2-167959 and Japanese Patent Publication No. Hei 8-22432 disclose a method of sending sediment from a pit through a sediment pressure pipe. An invention relating to a mud solidification treatment in which the discharged excavated earth and sand having a high moisture content is guided into a rotary kneader, and a high moisture treatment agent and an auxiliary agent are added and stirred and mixed to obtain solid treated residual soil. Is disclosed.

[0004]

In the above-described mud solidification treatment apparatus, the earth and sand excavated by the shield excavator is discharged out of the mine via a pressure pipe by a pressure pump installed behind the shield excavator. It is led to the mud solidification treatment equipment installed on the ground. The treated soil that has been solidified by the mud solidification treatment device is temporarily stored in a storage tank and then loaded on a dump truck or the like and transported to a disposal site or the like.

In the shield tunneling method, when a shield machine excavates a predetermined distance, a curved pressure plate called a segment is provided in contact with the tunnel wall in order to prevent collapse of a wall surface of a tunnel formed behind. It is assembled along the circumferential direction between the shield machine and the existing pressure plate. Since the shield excavator is propelled by taking a reaction force against the assembled stop plate, the earth excavation operation by the shield excavator naturally stops at the time of assembling the stop plate. Therefore, the excavated earth and sand is supplied to the mud solidification processing apparatus only when the shield excavator is excavating, and is not supplied at all during the operation of assembling the stop plate.

As described above, the supply and the stop of the excavated earth and sand are almost periodically repeated in the mud solidification processing apparatus. The required solidification processing capacity of the mud corresponds to the supply amount at the time of supplying the mud. Therefore, the mud solidification processing apparatus becomes a large-sized facility, and the installation space and site become large, and the equipment cost increases. In urban areas where there is no large open space, there is a case where it is not possible to secure a site for installing a mud solidification treatment device, so that excavation of a tunnel by a shield excavator itself may be restricted.

[0007] Further, in the rotating cylinder of the mud solidification treatment apparatus, the water in the mud carried in from the excavation site and the lime added as an auxiliary material cause an exothermic reaction, and the heat evaporates the water. Solidification of mud is promoted. However, with the stop of the periodic excavation operation as described above,
When the mud solidification processing device also periodically stops operating, the exothermic reaction also stops, the rotating cylinder cools down, and when the operation is restarted, the mud does not become hot, and the exothermic reaction is slow and the mud temperature rise slows down. There is a problem that the evaporation of water is small and the mud does not solidify.

As described above, since the treated soil immediately after the restart of operation has a high moisture content and cannot be transported by truck, the treated soil discharged at a predetermined time after the restart of operation is retained and reprocessed, or mud is removed. It is necessary to take measures such as prolonging the time required for the solidification treatment. For this reason, not only the work efficiency is remarkably reduced, but also extra personnel for confirming the condition of the discharged treated earth and sand must be arranged.

The present invention has been made in order to solve such a problem in the prior art, and does not require a large facility or a large site area, and furthermore, the excavation work of the shield machine is periodically stopped. It is another object of the present invention to provide a mud solidification treatment equipment that does not require a permanent staff member to check the quality of the treated soil when the operation is resumed.

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention comprises excavated earth and sand having a high water content formed by excavation operation when a shield excavator repeats excavation operation while being conveyed from underground. A storage tank for temporarily storing the mud, and conveying means for feeding the mud stored in the storage tank to the mud solidification processing device at a predetermined unit time conveyance amount, and Less than the unit time transport amount when transporting the mud from the inside of the tunnel to the ground, the metamorphic treatment operation of the mud by the mud solidification treatment device is continued even while the excavation of the shield machine is stopped, preferably The excavation and stoppage of the shield machine is repeated at a substantially constant cycle, and the mud solidification processing device that is performed while the shield machine is stopped excavating the mud stored in the storage tank is almost completely transformed. In which it was to be terminated at the end of excavation stop of de excavator.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention; FIG. 1 is a vertical sectional view showing the configuration of this example. In the figure, reference numeral 1 denotes a mud solidification treatment device disposed on the ground near the opening of the tunnel.
Is a storage tank for temporarily storing mud conveyed from the ground, 3 is a transfer pump for feeding the mud stored in the storage tank 2 into the rotary cylinder of the mud solidification processing device 1 at a predetermined feed amount, Reference numeral 4 denotes a mud supply pipe for guiding the mud sent from the transport pump 3 to the mud solidifying apparatus 1, reference numeral 5 denotes a solidifying material input apparatus for inputting a solidified material at a predetermined feed amount, and reference numeral 6 denotes a mud solidifying apparatus 1.
This is an earth removal tank where the solidified soil is deposited.

Reference numeral 7 denotes a shield excavator for excavating a face at the tip of a tunnel, 8 denotes a screw conveyor for conveying excavated earth and sand behind the shield excavator 7, and 9 denotes a screw conveyor 8
A pump 10 for sending the excavated earth and sand conveyed by the above to the ground through a mud transport pipe described below, 10 is a mud transport pipe for guiding the mud pumped by the pump 9 to the storage tank 2 outside the tunnel, 11
Is a discharging mechanism in which the mud is mainly stirred and mixed with the solidifying material and the auxiliary material, and is discharged. 12 is an opening / closing door for opening and closing the discharging opening of the discharging mechanism 11, 71 is a tip of the shield excavator 7. It is a cutting blade that is rotatably attached to the section and that makes rotary contact with the earth and sand of the face to excavate it.

Next, the operation of this embodiment will be described. The construction and operation of the shield machine 7 is the same as that of the conventional machine, and excavated in contact with the rotating cutting blade 71, and the soil containing water such as groundwater is removed behind the shield machine 7 by the screw conveyor 8. And sent out to the ground via a mud transport pipe 10 by a pressure pump 9. Mud transport pipe 1
The mud sent to the ground through zero is discharged to the upper part of the storage tank 2 and temporarily stored therein. The mud stored in the storage tank 2 is shielded by the transport pump 3 and the shield machine 7.
Irrespective of the excavation operation and the stoppage of the operation, a predetermined feed amount is fed into a rotary cylinder (not shown) of the mud solidification processing apparatus 1.

The mud solidification treatment apparatus 1 itself has no difference from the conventional one. That is, the mud sent into the rotary cylinder is stirred and mixed with the solidified material and the auxiliary material supplied from the solidified material charging device 5 by the rotating rotary cylinder, and the excavated soil with a high moisture content is in a mud state. A solid state with low moisture content results. The earth and sand which has been sent to the earth discharging mechanism unit 11 and is in a substantially solid state falls from the earth discharging port below the earth discharging mechanism unit 11 into the earth discharging tank 6 and is accumulated. The solidified sand deposited in the dumping tank 6 is loaded on a dump truck or the like and transported to a disposal site or another construction site. It should be noted that the mud solidification treatment apparatus 1 is, of course, continuously operated regardless of the operation and stoppage of the shield machine 7 as in the case of the transport pump 3.

[0015] in FIG. 2 and FIG. 3 is a time course of soil volume V _c per unit time discharged from the shield machine 7 respectively, reservoir mud weight stored in the 2 V _i and mud solidification processing apparatus 1 is a time characteristic diagram showing changes with time of the soil volume V _o per unit discharged time from the rotating cylinder. As shown in FIG. 2, the soil volume V _c per unit time discharged from the shield machine 7 during operation of the shield machine 7 becomes approximately constant value according to the soil of the excavation soil (excavated time t _ai), When stopped, it becomes 0 (assembly time t _bi ). When the shield machine 7 starts drilling operation started in the site, when the shield machine 7 has passed a predetermined time period from the start of the drilling operation, drilling mud is deposited in the reservoir 2 with a delay of time t ₁ Begin to.

The transport pump 3 starts feeding mud into the rotary cylinder of the mud solidification treatment apparatus 1 in synchronization with the accumulation of excavated earth and sand in the storage tank 2. At this time, the supply amount per transport pump 3 unit for supplying mud into the rotary cylinder time constant emissions considerably smaller conveying pump 3 from the soil volume V _c per unit time discharged from the shield machine 7 V _s It is set to a value near. Therefore, after the soil volume V _h is the time t ₁ elapses in the storage tank 2, reaching gradually maximum value during excavation operation completion increases (t _a1). When the assembly operation to attach the new stop plate to the tip of the stop plate which is assembled along the tunnel inner wall is started, the soil volume V _h of the reservoir 2 is gradually reduced, the stop plate assembly work is completed At the time (t _a1 + t _b1 ), it becomes almost 0, and when the next excavation operation is started, the mud transport pipe 10 is already filled with the previously pumped mud. Mud is immediately discharged into the storage tank 2 from the exit. In this manner, the excavation work / stop plate assembly work and the mud accumulation operation in the storage tank 2 in the next cycle are performed.

On the other hand, at the discharging opening of the discharging mechanism 11 for discharging the solidified sand that has been processed by the mud solidification processing apparatus 1, the opening and closing door 12 is opened when the shield machine 7 starts the excavating operation for the first time. It is closed and remains closed even after the time t ₁ has elapsed and the transport pump 3 starts supplying mud into the rotary cylinder. Then, the door opening the worker slightly door 12 at the time of the lapse of time t _2, confirmed to have sufficient rigidity to trucking inspect the properties of the discharged sand Then, the door 12 is fully opened for the first time. Immediately after the mud solidification treatment apparatus 1 receives mud from the transport pump 3 for the first time and starts the mud solidification treatment, the rotary cylinder is still cold, so the chemical reaction between the mud and quicklime is insufficient and the heat generation is also weak. For this reason, the opening and closing door 12 is closed and stays for a while in the soil discharging mechanism 11 to supplement the time required for a sufficient chemical reaction, promote heat generation, promote evaporation of the water in the muddy soil, and reduce the moisture content of the soil. To obtain sufficient hardness.

[0018] Thus, soil amount V _o per unit time of the sediment discharged from the soil discharge opening of the dumping mechanism 11 a while later than the shield machine 7 is time from the start of the excavation operation t ₁ When time t ₂ elapses, it rapidly increases from 0,
After reaching the maximum value, decreases and becomes constant value almost in a steady emissions V _s of approximately conveying pump 3, then, the predetermined value is maintained even after repeated cycling drilling operations, stop pressure plate assembly work You. Many operations of the stop plate assembly work are manually performed manually, but the stop plate assembly time t _bi required for the work is not so much different and is almost constant. On the other hand, the excavation work time t _ai fluctuates to some extent depending on the soil _properties of the excavated earth and sand. However, in the tunnel excavation work, the soil quality during the excavation hardly changes drastically, so the excavation work time t _a1 of the first cycle is measured at the beginning of the tunnel excavation work, and the transport pump 3 adapted to this is measured. be determined the conveyance amount per unit time, it can be made to be one period of the excavation work, stop plate assembly work at the end of the soil volume V _h of the reservoir 2 almost each 0.

As described above, when the cycle of the digging operation and the pressure plate assembling operation is constant, the digging operation time t _ai becomes a constant value t _a ,
Stop plate assembly time t _bi constant value t _b, and the addition, the soil per unit of time sediment discharged from mud solidification processing apparatus 1 in the steady state V _o is the constant emission of the transport pump 3 V
_Since it is equal to _s , V _o = V / (t _a + t _b ) (1) (where V is the amount of excavated soil per excavation cycle).

V = (π / 4) D ² × B (2) (where D is the outer diameter of the shield excavation and B is the axial length of the blocking plate) Further, the transport pump 3 is, for example, a pressure pump. Where V _s = V _o = (π / 4) d ² × St × n (3) (where d, St, and n are the piston diameter and the extrusion length of the pressure-feed pump, respectively) And the number of extrusions).

[0021] Therefore, if V = V _s, one period (t _a
+ Transport pump 3 between t _b) is ^{n = (D 2 × B)} / (d 2 × St) ...... (4) times pushed out without increasing the soil volume V _h of the reservoir 2 when, mud By continuously operating the solidification treatment device 1, the mud, which is excavated earth and sand having a high moisture content, discharged from the shield machine 7 can be transformed into a solid state with a small treatment capacity.

[0022]

As described above, according to the first aspect of the present invention, the storage tank for temporarily storing the mud conveyed from underground, and the mud stored in the storage tank are stored in the predetermined storage tank. A transporting means for feeding the mud solidification processing device in a unit time transport amount, wherein the unit time transport amount of the transport means is smaller than the unit time transport amount when the mud is transported from the underground tunnel to the ground, and the shield excavator Even when the excavation of the mud was stopped, the mud conversion treatment operation by the mud solidification treatment device was continued,
Since the amount of metamorphic treatment of mud per unit time by the mud solidification treatment device can be less than the unit time transport amount of mud from the inside of the tunnel to the ground, the equipment can be made relatively small,
Even if the site area is not very large, the mud solidification treatment equipment can be installed there.

According to the second aspect of the present invention, the excavation and the stop of the shield machine are repeated at a substantially constant cycle, and are stored in the storage tank by the mud solidification processing device performed while the excavation of the shield machine is stopped. Since the metamorphic treatment of the mud is finished almost at the end of the excavation stop of the shield machine,
Even if the operation is periodically stopped, continuous operation can be performed with almost no stop of the mud solidification treatment device. Therefore, it is not necessary to confirm the quality of the treated soil when restarting the operation of the mud solidification treatment device as before. It is possible to always obtain treated soil with constant properties.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view showing a configuration of a specific example of the present invention.

[Figure 2] Time elapsed characteristic diagram showing temporal changes in soil amount V _c per unit time discharged from the shield machine

[Figure 3] Time elapsed characteristic diagram showing temporal changes in soil amount V _o per unit discharged time from mud weight V _i and mud solidification processing apparatus stored in the storage tank

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mud solidification processing apparatus 2 Storage tank 3 Transport pump 5 Solidification material charging apparatus 6 Discharge accumulation tank 7 Shield excavator 8 Screw transport machine 9 Pressure pump 10 Mud transport pipe 11 Discharge mechanism

Claims (2)

[Claims] 1. A shield excavator for excavating a tunnel underground is formed by an excavation operation when the excavation operation is repeated while periodically stopping while a pressure stop plate for preventing the collapse of the wall is attached to a tunnel wall surface. A mud equipped with a mud solidification treatment device that agitates and mixes a solidified material containing an agent that generates heat by a chemical reaction with high-moisture content excavated soil conveyed to the ground and transforms it into low-moisture-content solid soil. In the solidification processing equipment, a storage tank for temporarily storing mud made of excavated earth and sand with a high moisture content conveyed from the ground,
When the mud stored in the storage tank is conveyed to the mud solidification treatment device at a predetermined unit time transfer amount, the unit is provided with a unit time transfer amount for transferring the mud from the underground tunnel to the ground. A mud solidification processing equipment device, wherein the mud conversion processing operation by the mud solidification processing device is continued even when the excavation of the shield excavator is stopped by making it less than the unit time transport amount. 2. The excavation and stoppage of the shield machine is repeated at a substantially constant period, and the mud solidification processing device performed during the halt of the shield machine excites the metamorphic treatment of the mud stored in the storage tank. 2. The mud solidification treatment facility apparatus according to claim 1, wherein the apparatus ends when the excavation stops.