Sludge measurement system

Abstract

To provide a sludge measurement system capable of measuring a sludge amount in realtime with less error.SOLUTION: A sludge measurement system of the present invention comprises: an excavator 1 including a cutter chamber 3 having a cutter 2 for drilling sediment at a tip, a high concentration slurry supply tube 11 for pneumatically feeding high concentration slurry to the cutter chamber 3, a pinch valve 5 for intermittently discharging mud including excavated soil from the cutter chamber 3, a sludge receiving 6 for storing sludge M discharged from the pinch valve 5, a suction tube 13 connected to the sludge receiving 6 and for discharging the sludge M from the sludge receiving 6 to the outside of the pit, and a load cell 24 provided at the sludge receiving 6 and for measuring a weight of the sludge M discharged from the pinch valve 5; and an operation part electrically connected with the road cell 24 and for integrating the sludge weight of the number of times when a sludge valve is opened until reaching a predetermined excavation length and calculating the sludge weight at the predetermined excavation length.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a sludge measurement system that is applied to a thick mud jacking method for constructing a pipe or conduit by underground excavation. [Background technology]

[0002] The concentrated mud jacking method involves pumping high-concentration mud into the cutter chamber of a tunneling machine, the front of which is sealed off by a partition, and then stirring and mixing the excavated soil and high-concentration mud in the cutter chamber to produce mud that acts on the face of the tunnel.This maintains mud pressure that counteracts earth and water pressure, stabilizing the face while the cutter is used to excavate the tunnel, and the thrust of a thrust jack installed in the shaft is used to push and press in a thrust pipe to construct a tunnel (Patent Document 1).

[0003] The excavated soil that turns into mud in the cutter chamber is usually discharged into a mud receiver at the rear of the tunneling machine using the pressure inside the cutter chamber. The discharged mud is then vacuum transported from the mud receiver to a waste soil storage tank above the starting shaft by a mud suction and discharge device installed on the ground, where it is stored.

[0004] In the thick mud jacking method, if too much waste mud is taken into the tunneling machine during excavation, it may cause ground subsidence, so the amount of waste mud must be properly managed. Generally, this is done by measuring the amount of waste mud stored in the waste soil storage tank. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 5537850 Summary of the Invention [Problem to be solved by the invention]

[0006] When the sludge in the sludge receiver is sent to the soil storage tank by vacuum transport, the sludge often remains in the pipes without being discharged, which causes errors in the amount of sludge discharged. Furthermore, because the sludge in the soil storage tank is collected and removed by a vacuum truck during construction, it is difficult to grasp the exact amount of sludge discharged in real time.

[0007] An object of the present invention is to provide a sludge measurement system that can measure the amount of sludge in real time with little error. [Means for solving the problem]

[0008] The sludge measurement system of the present invention, which solves the above-mentioned problems, comprises a tunneling machine equipped with a cutter chamber having a cutter at its tip for excavating earth and sand, a high-concentration mud supply pipe that pressure-feeds high-concentration mud into the cutter chamber, a sludge discharge valve that intermittently discharges mud including excavated earth and sand from the cutter chamber, a sludge discharge receiver that collects the sludge discharged from the sludge discharge valve, a sludge discharge pipe connected to the sludge discharge receiver for discharging the sludge from the sludge discharge receiver outside the mine, and a weight measuring device attached to the sludge discharge receiver that measures the weight of the sludge discharged from the sludge discharge valve; and a calculation unit electrically connected to the weight measuring device that measures and accumulates the amount of sludge discharged each time the sludge discharge valve is opened and calculates the amount of sludge discharged for a specified excavation length. [Effects of the Invention]

[0009] According to the present invention, the amount of sludge is measured when it is discharged from the cutter chamber into the sludge receiver, so there is little error and the amount of sludge can be managed in real time, making it possible to quickly identify any excessive sludge intake, etc. This prevents ground subsidence and enables safe construction. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is an explanatory diagram showing an example of a mud-thickening jacking method to which a mud discharge measurement system according to an embodiment of the present invention is applied. FIG. [Figure 2]1 is a cross-sectional view of a tunneling machine showing a state in which a sludge discharge valve is closed in a sludge discharge measurement system according to one embodiment of the present invention. [Figure 3] FIG. 1 is a cross-sectional view of the tunneling machine showing the mud discharge valve in an open state. [Figure 4] 1(a) and 1(b) are a plan view and a side view showing the mounting structure of a load cell provided in a mud discharge receiver. [Figure 5] 5(a) is an enlarged view of part A in FIG. 4(b), and (b) is a side view seen from direction B in FIG. 5(a). [Figure 6] 1 is a flowchart showing a method for measuring the amount of sludge using a sludge measurement system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] The sludge measurement system according to one embodiment of the present invention will be described below. Figure 1 shows an example of a thick mud jacking method to which the sludge measurement system according to one embodiment of the present invention is applied.

[0012] In Figure 1, reference numeral 1 denotes a tunneling machine, with a cutter 2 (face) attached to the tip of this tunneling machine 1, which is used to excavate the ground. At the tip of the tunneling machine 1, a cutter chamber 3 sealed by a partition is provided, which is filled with high-concentration mud water under pressure and which allows the cutter 2 to excavate while stabilizing it. The tunneling machine 1 excavates the ground using the thrust of a main jack 40 installed in a vertical shaft 4, while pressing a propulsion pipe 41 into the ground from a starting tunnel mouth 42 to construct a culvert. The high-concentration mud is produced in a mud-producing device 9 outside the shaft 4 and is pumped by a pump 10 through a high-concentration mud supply pipe 11 to the cutter chamber 3.

[0013] The excavated soil is agitated and mixed with high-concentration mud water in the cutter chamber 3 at the tip, where it plastically fluidizes and becomes high-concentration mud water. The pressure difference between the cutter chamber 3, which is pressurized by this high-concentration mud water, and the inside of the tunneling machine 1 is used to intermittently open and close a pinch valve 5 (sludge discharge valve), and the soil is discharged into a mud discharge receiver 6. For example, an air-pressurized pinch valve can be used as the pinch valve 5, and it is configured so that compressed air is injected into the valve body from a compressor 7 via an air hose 8, pressing a rubber sleeve 51 and cutting off the flow of fluid. For example, the pinch valve 5 can be remotely controlled by attaching a solenoid valve, pressure reducing valve, etc. to the air hose 8.

[0014] The sludge discharged into the sludge receiver 6 is carried out of the shaft 4 by a sludge suction and discharge device 12 (vacuum generator) through a suction pipe 13 (suction hose) connected to the sludge receiver 6, and is sent from a sludge container tank 14 to a sludge storage tank 15. The sludge stored in the sludge storage tank 15 is either removed by a vacuum truck or solidified and then transported and disposed of by truck. Transportation is usually carried out as needed during construction.

[0015] A lubricant injection device 16 is provided outside the shaft 4, and lubricant is injected from this lubricant injection device 16 via a pump 17 and a lubricant supply pipe 18 into a tail void (excavation space, not shown) that forms on the outer surface of the tunneling machine 1 immediately after excavation. This reduces the frictional resistance between the tunneling machine 1 and the ground. Examples of lubricants include the conventional two-component solidifying lubricants.

[0016] 2 and 3 respectively show the closed and open states of the pinch valve 5 in the tunneling machine 1. One end of a sludge discharge pipe 19 for discharging sludge M from the cutter chamber 3 is connected to the cutter chamber 3, and the other end is connected to the pinch valve 5. 2 and 3, reference numeral 20 denotes a cutter motor for driving (rotating) the cutter, and reference numeral 21 denotes a pivot jack for controlling the attitude and correcting the direction of the tunneling machine.

[0017] As described above, one end (sludge inflow side) of the pinch valve 5 is connected to the sludge discharge pipe 19, and the other end (sludge outflow side) is connected in turn to the emergency gate 22 and the discharge port 23. The emergency gate 22 closes automatically in the event of a power outage or emergency to prevent sludge from entering. The discharge port 23 is cylindrical, and when the pinch valve 5 is open (see FIG. 3), the sludge M is poured into the sludge receiver 6. The discharge port 23 may be an elbow-shaped port that is bent downward. The sludge receiver 6, which receives the sludge that falls from the discharge outlet 23, consists of a container with an open top, and a suction pipe 13 is connected to the side to discharge the stored sludge outside the mine.

[0018] Next, a method for discharging the sludge M and a method for measuring the amount of sludge will be explained with reference to Figures 2 and 3. As shown in Figure 2, with pinch valve 5 closed, excavation is carried out by the tunneling machine 1 while supplying highly concentrated mud water into cutter chamber 3. As a result, when the earth pressure in cutter chamber 3 reaches the upper limit range, this is detected by a sensor (not shown), and the supply of compressed air is stopped by closing the solenoid valve attached to air hose 8 of compressor 7, and sleeve 51 of pinch valve 5 is opened to start discharging the sludge M (see Figure 3). The upper limit range of earth pressure refers to a range that includes the upper limit value of earth pressure in cutter chamber 3 and values ​​close to it.

[0019] The pressure inside the cutter chamber 3 causes the waste sludge M to be discharged from the open pinch valve 5 and dumped into the waste sludge receiver 6 through the emergency gate 22 and the discharge port 23. The dumped waste sludge M is then discharged outside the mine via the suction pipe 13. When the earth pressure inside the cutter chamber 3 reaches the lower limit, this is detected by a sensor, and the supply of compressed air is started by opening a solenoid valve or the like, which presses the sleeve 51 of the pinch valve 5 and closes the pinch valve 5. The lower limit of the earth pressure refers to the range that includes the lower limit of the earth pressure inside the cutter chamber 3 and values ​​close to it.

[0020] The pinch valve 5 can be opened and closed by the operator or by a command signal from the control unit. The control unit detects the soil pressure inside the cutter chamber 3 and opens and closes the pinch valve 5. The amount of sludge discharged from the cutter chamber 3 is measured based on the opening and closing of the pinch valve 5, and the amount of sludge discharged is managed to ensure that it is appropriate. If the amount of sludge discharged becomes too high, there is a risk that excessive soil and sand will be taken in, causing ground subsidence, etc.

[0021] In this embodiment, in order to manage the amount of sludge in real time, a load cell 24 (weight measuring device) is provided in the sludge receiver 6, as shown in FIGS. 4(a) and (b) are a plan view and a side view showing the mounting structure of the load cell 24 provided in the mud receiver 6. As shown in the figure, the load cell 24 is attached to the four corners of the bottom of the rectangular mud receiver 6, and is electrically connected to the calculation unit in the control unit. 5(a) is an enlarged view of part A in FIG. 4(b), and FIG. 5(b) is a side view seen from direction B in FIG. 5(a).

[0022] 5(a) and (b) show an example in which a beam-type load cell is used as the load cell 24. The load cell 24 is installed on a swivel foot 60. The swivel foot 60 is placed on a base 65 for installing the mud receiver 6, and is fixed with a bolt 62 via an adjuster pad fixing plate 61. The load cell 24 is fixed with a bolt 64 to one side of an angle 63, the other side of which is fixed to the mud receiver 6. One end of a cable 66 is connected to the load cell 24 for electrical connection with the calculation unit. The load cells 24 are not limited to being installed at the four corners of the bottom of the mud collector 6, but may be installed at, for example, three corners, two corners, or the center of the bottom of the mud collector 6, as long as they can support the load of the mud collector 6. Furthermore, the load cell 24 is not limited to the beam type, and for example, a strain gauge type, a platform type, an S-beam type, a canister type, a tension / compression type, etc. may also be used.

[0023] Next, a method for measuring the amount of discharged sludge in this embodiment will be explained with reference to Figure 6. When the earth pressure in the cutter chamber 3 reaches an upper limit due to the excavation of the tunneling machine 1, the solenoid valve of the pinch valve 5 is opened and a signal is sent. When the solenoid valve receives a signal that it is in an open state, weight measurement begins using the load cell 24 attached to the discharged sludge receptacle 6. The measurement begins by measuring the weight (w1) of the discharged sludge receptacle 6 when the pinch valve 5 is opened (before the discharged sludge M starts to be poured in). This is because the discharged sludge receptacle 6 to be measured contains some amount of sludge M that was not discharged in the previous sludge discharge operation and therefore the amount of discharged sludge cannot be calculated accurately from the weight of the discharged sludge receptacle 6 itself alone.

[0024] The calculation unit for measuring the amount of sludge discharged is basically configured to measure the weight (w1) of the sludge receiver 6 before the start of the discharge of the sludge M, and the weight (w2) of the sludge receiver 6 after the pinch valve 5 is closed from the start of the discharge of the sludge M, and calculate the amount of sludge discharged using the formula: w2-w1.

[0025] However, immediately after opening the pinch valve 5, the soil and sand (sludge) falls into the sludge receptacle 6 all at once, which may cause an impact load. Therefore, after opening the pinch valve 5, the weight of the sludge M is measured after waiting until the sludge M has settled down (i.e., excluding the initial period after the start of the pouring). Specifically, for example, the pinch valve 5 is opened, and measurement is started a predetermined time after the start of the pouring of the sludge M (e.g., 2 to 5 seconds), and the weight (w21) of the sludge receptacle 6 is measured when all the sludge M has entered the sludge receptacle 6. The increase in the amount of waste sludge M is calculated by subtracting the weight (w1) of the waste sludge receiver 6 when the pinch valve 5 is opened from the weight (w21) of the waste sludge receiver 6 when all the waste sludge M is inside the waste sludge receiver 6. In other words, the increase in the amount of waste sludge = w21 - w1. However, it is necessary to take into account the weight (w22) of the waste sludge carried out in 2 to 5 seconds.

[0026] The weight (w22) of the waste sludge carried out from the suction pipe 13 within the predetermined time (for example, 2 seconds) from the start of the introduction of the waste sludge M is experimentally determined in advance. Then, the weight (w2) can be obtained by adding the weight (w22) of the waste sludge carried out to the weight (w21) of the waste sludge receiver 6. That is, the formula is w21 + w22 = w2, and the overall amount of waste sludge can be measured by the formula: w21 + w22 - w1.

[0027] The time between opening pinch valve 5 and starting weight measurement should be long enough to avoid the effects of impact loads, and should be determined after confirming the construction status. In other words, since the time between opening pinch valve 5 and starting weight measurement may vary slightly depending on the target soil type, groundwater pressure, muddy water material, etc., it is preferable to set this time during measurement. Normally, it is appropriate to start measuring weight (w21) 2 to 5 seconds after opening pinch valve 5.

[0028] The weight (w22) of the waste sludge M is determined in advance. Since waste sludge is constantly being removed from the waste sludge receptacle 6 by the suction pipe 13, the weight (w22) of the waste sludge M removed from the waste sludge receptacle 6 by the suction pipe 13 at the beginning of the introduction of the waste sludge M (for example, 2 seconds) is measured experimentally in advance. The weight (w22) of the waste sludge M removed from the waste sludge receptacle 6 by the suction pipe 13 is determined, for example, by opening the pinch valve 5, allowing all the waste sludge M to enter the waste sludge receptacle 6, stopping excavation (hence the opening and closing of the pinch valve 5), and measuring the weight loss of the waste sludge receptacle 6 per second while sucking and removing the waste sludge M from the waste sludge receptacle 6 by the suction pipe 13. From this, the average weight loss of the waste sludge receptacle 6, i.e., the amount of waste sludge suctioned per second (kg / sec), is determined. Measurements are preferably performed during actual construction. In this way, the weight (w22) of the waste sludge M at the beginning of the introduction of the waste sludge M can be determined. For example, the weight (w22) of the waste sludge M for 2 seconds after the start of the introduction of the waste sludge M can be calculated by multiplying the above-mentioned waste sludge suction amount (kg / sec) by 2 seconds. The removal of sludge from the sludge receiver 6 may be linked to the opening and closing of the pinch valve 5. That is, the removal of sludge from the sludge receiver 6 may be stopped when the pinch valve 5 is opened, and the removal of sludge from the sludge receiver 6 may be started when the pinch valve 5 is closed. Furthermore, the weights (w1), (w2) and (w21) described above all include the weight of the sludge receiver 6, but the weight of the sludge receiver 6 may be subtracted from these weights before calculating the amount of sludge discharged using the above formula.

[0029] As excavation continues while pumping high-concentration mud water into the cutter chamber 3, the earth pressure reaches the lower limit and the pinch valve 5 is closed. When the earth pressure in the cutter chamber 3 rises again and reaches the upper limit, the pinch valve 5 is opened, the soil (sludge) is discharged into the sludge receiver 6, and its weight (w2) is measured, and this operation is repeated as described above (see Figure 6). In this way, the continuous amount of sludge discharged as the tunneling machine 1 excavates can be measured in real time. Therefore, a calculation unit electrically connected to the load cell 24 accumulates the amount of sludge discharged the number of times the pinch valve 5 opens. The tunneling length of the tunneling machine 1 during this time is measured by measuring the jack stroke of the main push jack 40, and the amount of sludge discharged at a specified tunneling length is calculated from the formula: accumulated sludge discharge amount / tunneling length, thereby making it possible to manage the amount of sludge discharged. The measurement results of the amount of sludge discharged can be displayed on a management monitor (not shown). The predetermined excavation length may be, for example, the length of one jacking pipe or the length of one ring of a segment in a shield tunneling method, but may also be something else (for example, per 1 m of excavation length).

[0030] It is also preferable to convert the amount of sludge discharged (weight) into volume and manage it accordingly. In the mud-thickening method, the amount of sludge discharged is calculated as (amount of excavated soil + amount of mud injected - remaining tail void) x 50% = sludge discharged, and the amount of sludge discharged is often managed by volume. To convert it into volume, the specific gravity of the sludge discharged is determined using a mud hydrometer (mud balance) or similar, and the sludge volume is calculated in the calculation unit by dividing the sludge discharged weight by the specific gravity.

[0031] If the measured sludge discharge rate is higher than the desired set range, the excavation volume is too large, so excavation should be stopped and chemical injection should be performed. If the sludge discharge rate is lower than the desired set range, the high concentration mud water sent to the cutter chamber 3 has permeated into the ground and is lost, so measures such as changing the mud water material should be taken.

[0032] The waste mud M thrown into the waste mud receiver 6 is sucked and discharged outside the mine through a suction pipe 13 by a mud suction and earth discharge device 12.

[0033] According to this embodiment, as described above, the amount of sludge can be measured and managed in real time, so that excessive intake of sludge, etc. can be detected in a short time. This prevents ground subsidence, etc., and enables safe construction.

[0034] Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications and improvements are possible within the scope of the present invention. For example, the above embodiments are based on the mud jacking method, but they can also be applied to the mud jacking method, the earth pressure jacking method, and the earth pressure shield method. Furthermore, in the above embodiments, a load cell 24 is used as a weight measuring device, but this is not limited to the load cell 24, and various weight measuring devices can be used. [Explanation of symbols]

[0035] 1 excavator 2 cutters 3 Cutter Chamber 4 Shaft 5 Pinch valve (sludge discharge valve) 51 Sleeve 6 Mud tray 7 Compressor 8 Air Hose 9 Sludge production equipment 10 Pump 11 Mud water supply pipe 12 Sludge injection device 13 Suction pipe (sludge removal pipe) 14 Soil disposal container tank 15 Soil disposal storage tank 16 Lubricant injection device 17 Pump 18 Slub material supply pipe 19 Sludge drainage pipe 20 Cutter motor 21 Center-bending jack 22 Emergency Gate 23 Sludge drainage port 24 Load cell (weight measuring device) 40 Base jack 41 Propulsion tube 42 Departure Mine Entrance 60 Swivel Foot 61 Fixing plate 62, 64 volts 63 Angle 65 Foundation 66 Cable M Sludge removal

Claims

1. a cutter chamber having a cutter at its tip for excavating earth and sand; a high-concentration mud water supply pipe for pumping high-concentration mud water to the cutter chamber; a mud discharge valve that intermittently discharges mud including excavated soil from the cutter chamber; a sludge receiver for receiving the sludge discharged from the sludge discharge valve; a sludge discharge pipe connected to the sludge receiver for discharging the sludge from the sludge receiver to the outside of the mine; a weight measuring device provided in the sludge receiver for measuring the weight of the sludge discharged from the sludge discharge valve; a tunneling machine equipped with a calculation unit electrically connected to the weight measuring device, which calculates the weight of sludge discharged at the predetermined excavation length by accumulating the weight of sludge discharged the number of times the sludge discharge valve is opened until the predetermined excavation length is reached; Equipped with The calculation unit receives a signal that the sludge valve is open, measures the weight (w1) of the sludge receiver measured before the start of sludge introduction, and the weight (w2) of the sludge receiver from the start of sludge introduction to the closing of the sludge valve, and calculates the sludge weight using the formula: (w2) - (w1); The weight (w2) of the waste sludge receiver is the sum of the weight (w22) of the waste sludge at the beginning of the start of the introduction of the waste sludge and the weight (w21) of the waste sludge introduced into the waste sludge receiver from the start of the introduction, excluding the beginning of the introduction, until the sludge valve is closed, The weight (w22) of the sludge discharged at the beginning of the charging period is the weight of the sludge discharged from the sludge receiver during the beginning of the charging period, measured in advance. Sludge discharge measurement system.

2. The sludge measurement system according to claim 1, further comprising a control unit that opens the sludge discharge valve when the soil pressure in the cutter chamber reaches an upper limit range and closes the sludge discharge valve when the soil pressure reaches a lower limit range.

3. 3. The sludge measurement system according to claim 1, wherein the initial period of introduction is a period within a range of 2 to 5 seconds from the start of introduction of the sludge.

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