Tunnel water pressure regulating device

Abstract

To surely eliminate a state in which excessive water pressure is unevenly applied to lining concrete by smoothly flowing and draining water up to the water intake position of a water intake pipe where a pressure regulating valve is installed.SOLUTION: A tunnel water pressure regulating device adjusts the water pressure applied to the outside of a waterproof sheet 1 laid on the outside of a lining concrete 103 of a tunnel 100, and comprises a waterproof sheet 1 composed of an impermeable layer 2 and a water-conducting layer 3 laminated on its outside, the waterproof sheet 1 being provided with support structures 4 interspersed on the water-conducting layer 3 to resist compression in the thickness direction, a water intake pipe 8 that penetrates the impermeable layer 2 and the lining concrete 103 to reach the water-conducting layer 3 and takes in water outside the waterproof sheet 1, a water pressure gauge 30 installed in the water intake pipe 8 inside the lining concrete 103, and a pressure regulating valve 40 installed in the water intake pipe 8 downstream of the water pressure gauge 30 and that opens and closes in response to the water pressure measured by the water pressure gauge 30.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a tunnel water pressure adjusting device that adjusts the water pressure applied to the outside of a waterproof sheet laid on the outside of a tunnel lining concrete. [Background technology]

[0002] Conventionally, drainage and watertight types of waterproofing are known for the NATM construction method for mountain tunnels. As shown in Figure 7(a), a drainage tunnel 200 has a waterproof sheet 204 laid on the outside of a concrete lining 201, covering an arch section 202 and both side wall sections 203. Spring water that forms on the outer surface of the waterproof sheet 204 at the arch section 202 or the like is guided downward along the waterproof sheet 204, and the water is collected in a water collection material 205 located below the side wall sections 203 and in a central water collection pipe 206 located in the center of the tunnel bottom. In the drainage tunnel 200, the waterproof sheet 204 prevents groundwater from leaking into the tunnel, and water that flows along the outer surface of the waterproof sheet 204 is drained outside the tunnel via the water collection material 205 and the central water collection pipe 206.

[0003] As shown in Figure 7(b), a watertight tunnel 300 has a waterproof sheet 302 laid on the outside of a concrete lining 301 so as to cover the entire surface of the tunnel, and the waterproof sheet 302 covering the entire surface of the tunnel prevents groundwater from leaking into the tunnel. In a watertight tunnel 300, in order to prevent any groundwater in the natural ground from entering the tunnel space, the water pressure applied from the outside to the waterproof sheet 302 and concrete lining 301 is large. In Figure 8, GL is the ground surface and WL is the groundwater level.

[0004] Because water pressure applied from the outside is large, it is necessary to use a thick waterproof sheet 302 for the watertight tunnel 300 that can withstand the water pressure, and the lining concrete 301 for the watertight tunnel 300 must have a large amount of rebar and be thick, such as one with a multiple rebar structure 303 installed inside. When a thick waterproof sheet 302 or a thick lining concrete 301 is installed, the excavation cross section to ensure the same tunnel interior cross section becomes larger, which reduces workability and increases construction costs.

[0005] One technology proposed to solve the problems of watertight tunnels is the tunnel structure described in Patent Document 1. The tunnel structure described in Patent Document 1 involves covering the outside of the concrete lining with a waterproof sheet, installing a water intake pipe that penetrates the concrete lining and the waterproof sheet, and installing a pressure control valve at the end of the water intake pipe on the tunnel's interior side. The waterproof sheet may be a single-layer waterproof sheet like a water-stopping layer, or a multi-layer structure consisting of a protective layer made of nonwoven fabric and a water-stopping layer made of an impermeable material. In this tunnel structure, when the water pressure acting on the tunnel becomes too high, the pressure control valve drains groundwater to reduce the water pressure acting on the tunnel. This eliminates the need for an excessively thick waterproof sheet or an excessively sturdy and thick concrete lining, improving workability and reducing construction costs. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 6325838 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the tunnel structure of Patent Document 1 uses either a single-layer waterproof sheet as a water-stopping layer or a multi-layer waterproof sheet consisting of a nonwoven fabric and a water-stopping layer, which prevents water from smoothly flowing and draining to the intake position of the water intake pipe equipped with a pressure regulating valve, making it difficult to resolve the condition in which excessive water pressure is unevenly applied to the lining concrete. In other words, when a single-layer waterproof sheet is used as a water-stopping layer, when excessive water pressure is applied to the single-layer waterproof sheet and the lining concrete, sufficient gaps are not formed to allow water to smoothly flow to the intake position of the water intake pipe equipped with a pressure regulating valve, preventing water from smoothly flowing to the intake position of the water intake pipe equipped with a pressure regulating valve. Furthermore, when a multi-layer waterproof sheet consisting of a nonwoven fabric and a water-stopping layer is used, when excessive water pressure is applied to the waterproof sheet and the lining concrete, the nonwoven fabric, which acts as a water-conducting layer, may locally collapse or be compressed in the thickness direction, reducing its water-conducting function and preventing water from smoothly flowing to the intake position of the water intake pipe equipped with a pressure regulating valve.

[0008] Therefore, when draining groundwater using a pressure regulating valve to adjust the water pressure applied to the outside of the waterproof sheet, there is a need for technology that can smoothly drain water up to the intake position of the intake pipe where the pressure regulating valve is installed, and can reliably eliminate the condition in which excessive water pressure is applied unevenly to the lining concrete.

[0009] The present invention has been proposed in light of the above-mentioned problems, and aims to provide a tunnel water pressure adjustment device that, when draining groundwater with a pressure adjustment valve to adjust the water pressure applied to the outside of a waterproof sheet, can smoothly drain water up to the water intake position of the water intake pipe where the pressure adjustment valve is installed, and can reliably eliminate the condition in which excessive water pressure is applied unevenly to the lining concrete. [Means for solving the problem]

[0010] The tunnel water pressure adjustment device of the present invention is a tunnel water pressure adjustment device that adjusts the water pressure applied to the outside of a waterproof sheet laid on the outside of a tunnel's lining concrete, and is characterized by comprising: an impermeable layer; a water-conducting layer that is stacked on the outside of the impermeable layer; the waterproof sheet that is arranged so that support structures that resist compression in the thickness direction are scattered across the water-conducting layer; a water intake pipe that is arranged to penetrate the impermeable layer and the lining concrete and reach the water-conducting layer and takes in water outside the waterproof sheet; a water pressure gauge that is installed in the water intake pipe inside the lining concrete; and a pressure adjustment valve that is installed in the water intake pipe downstream of the water pressure gauge and opens and closes in accordance with the water pressure measured by the water pressure gauge. This allows the waterproof sheet's water-conducting layer to be dotted with support structures that resist compression in the thickness direction, ensuring gaps that allow water to flow smoothly into the water-conducting layer. Therefore, when the pressure regulating valve is used to drain groundwater and adjust the water pressure on the outside of the waterproof sheet, the water can be smoothly drained to the intake position of the intake pipe where the pressure regulating valve is installed, reliably eliminating the situation where excessive water pressure is applied unevenly to the lining concrete.

[0011] In the tunnel water pressure adjusting device of the present invention, the water conducting layer has a hydraulic conductivity of 10 -2 It is characterized by a permeable layer of more than m / s. This allows water to flow more smoothly to the intake position of the water intake pipe where the pressure regulating valve is installed and then be discharged.

[0012] The tunnel water pressure regulating device of the present invention is characterized in that the water intake pipe discharges the water taken in into a dedicated water conduit extending in the longitudinal direction of the tunnel. According to this system, the water taken in by the intake pipe is spring water generated from the natural ground, so by discharging it from the intake pipe into a dedicated water conduit, it can be distinguished from wastewater generated by construction work inside the tunnel space, which requires purification treatment, and the natural ground spring water can be ultimately discharged into rivers or the natural ground via a dedicated water conduit without purification treatment. In other words, wastewater treatment can be carried out economically while taking into consideration the environmental load.

[0013] The tunnel water pressure adjusting device of the present invention is characterized in that a substructure heavier than the design requirement is installed in the tunnel to resist the buoyancy of groundwater. According to this, for example, if the thickness of the entire lining concrete is increased to resist the buoyancy of groundwater, the cross section of the tunnel excavation will become larger and construction costs will increase significantly. However, by providing a lower structure that is heavier than the design required to resist the buoyancy of groundwater, it is possible to reduce construction costs while suppressing the impact of groundwater buoyancy on the tunnel.

[0014] The tunnel water pressure regulating device of the present invention comprises a wireless communication unit that transmits the measured water pressure data of the water pressure gauge and opens and closes the pressure regulating valve in response to receiving a valve opening / closing signal, and a drainage control device that receives the measured water pressure data of the water pressure gauge from the wireless communication unit and transmits a valve opening / closing signal to the wireless communication unit, wherein the drainage control device stores a drainage start threshold and a drainage stop threshold in a configurable manner, executes a valve opening / closing determination process, and transmits a valve open signal to the wireless communication unit if it determines that the received measured water pressure data of the water pressure gauge exceeds the drainage start threshold or is equal to or greater than the drainage start threshold, and transmits a valve close signal to the wireless communication unit if it determines that the received measured water pressure data of the water pressure gauge is less than the drainage stop threshold or is equal to or less than the drainage stop threshold. This allows the necessary opening and closing operations of the pressure control valve to be performed automatically without relying on manual opening and closing operations of the pressure regulating valve, and by storing the drainage start threshold and drainage stop threshold in a configurable manner in a drainage control device that communicates wirelessly with the wireless communication unit corresponding to the pressure regulating valve, the drainage start threshold and drainage stop threshold appropriate for water pressure adjustment can be flexibly set in a location away from the wireless communication unit.

[0015] The tunnel water pressure adjustment device of the present invention is characterized in that the water intake pipe, the water pressure gauge, the pressure adjustment valve, and the wireless communication unit are provided at each of a plurality of positions spaced apart in the longitudinal direction of the tunnel, and the drainage control device receives measured water pressure data of the water pressure gauge from each of the wireless communication units at the plurality of positions, performs a valve opening / closing determination process for each of the plurality of positions, and transmits a valve opening / closing signal to each of the wireless communication units in accordance with the valve opening / closing determination process. This allows one drainage control device to control the opening and closing of pressure regulating valves installed at multiple locations, and if there is a change in the drainage start threshold and drainage stop threshold values ​​appropriate for water pressure regulation, each pressure control valve can be easily made to open and close appropriately by changing the drainage start threshold and drainage stop threshold settings of the drainage control device.In addition, pressure regulating valves can be flexibly opened and closed according to the water pressure conditions at each of the multiple locations along the tunnel length.

[0016] The tunnel water pressure adjustment device of the present invention is characterized in that the drainage control device records the measured water pressure data of the water pressure gauge received from each of the wireless communication units at the multiple locations in a chronological order in a management information recording unit in correspondence with location identification information, and records the record of the valve opening / closing signal transmitted in response to the valve opening / closing determination process in correspondence with the location identification information and the transmission date and time in the management information recording unit. With this system, the drainage control device can record the time-series measured water pressure data from each water pressure gauge at multiple locations and the open / close status of the pressure regulating valve at each location as management information, and use this as maintenance data. Also, in normal tunnel maintenance, the condition of the lining concrete and the amount of displacement of the internal cross section are monitored to evaluate the soundness of the tunnel, but the water pressure measured by the water pressure gauge, which corresponds to the water pressure acting on the lining concrete, can be added to the monitoring items, allowing for a more accurate evaluation of the tunnel soundness.

[0017] The tunnel water pressure regulating device of the present invention is characterized in that the water intake pipe discharges the water taken in into a dedicated water conduit extending in the longitudinal direction of the tunnel, and a water volume sensor with wireless communication function is provided at a point where all the water is collected in a water collection pipe that collects the water flowing through the dedicated water conduit, and the drainage control device continuously receives water volume data from the water volume sensor with wireless communication function and records the integrated flow rate for a predetermined period of time, calculated by accumulating the received water volume data, in the management information recording unit. According to this, in normal tunnel maintenance, the condition of the lining concrete and the amount of displacement of the internal cross section are monitored to assess the integrity of the tunnel, but it is now possible to add to the monitoring items both the water pressure data measured by the water pressure gauge, which corresponds to the water pressure acting on the lining concrete, and the cumulative flow rate of water springing from the ground over a specified period of time, allowing for a more accurate assessment of the tunnel integrity. [Effects of the Invention]

[0018] According to the tunnel water pressure adjustment device of the present invention, when groundwater is drained using a pressure adjustment valve to adjust the water pressure applied to the outside of the waterproof sheet, the water can be smoothly drained to the intake position of the water intake pipe where the pressure adjustment valve is installed, thereby reliably eliminating the condition in which excessive water pressure is applied unevenly to the lining concrete. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a schematic perspective view showing an example of a tunnel in which a tunnel water pressure adjusting device according to an embodiment of the present invention is installed; [Figure 2] 1 is a schematic cross-sectional view illustrating a tunnel water pressure adjusting device according to an embodiment of the present invention; [Figure 3] 1A is a perspective view showing a first example of a waterproof sheet in a tunnel water pressure adjusting device according to an embodiment, and FIG. 1B is a perspective view showing a second example of the waterproof sheet. [Figure 4] 1 is a block diagram showing a drainage control device, a wireless communication unit, a water pressure gauge, a pressure adjustment valve, and a water volume sensor with wireless communication function in a tunnel water pressure adjustment device according to an embodiment. FIG. [Figure 5]4 is a flowchart showing a drainage control process performed by the tunnel water pressure adjusting device of the embodiment. [Figure 6] FIG. 1 is a schematic diagram illustrating an example of a tunnel equipped with a substructure heavier than the design requirement. [Figure 7] (a) is a schematic perspective view showing an example of a conventional drainage tunnel, and (b) is a schematic perspective view showing an example of a conventional watertight tunnel. [Figure 8] An explanatory diagram illustrating the water pressure acting on a conventional watertight tunnel. DETAILED DESCRIPTION OF THE INVENTION

[0020] [Tunnel water pressure adjusting device of the embodiment] A tunnel water pressure adjusting device according to an embodiment of the present invention adjusts the water pressure applied to the outside of a waterproof sheet laid on the outside of a tunnel's lining concrete, and is installed in a tunnel 100, for example, as shown in Figures 1 and 2. In tunnel 100, shotcrete 102 is laid on the tunnel's inner circumferential surface of natural ground 101, a waterproof sheet 1 is laid on the inner circumferential side of shotcrete 102, and lining concrete 103 is laid on the inner circumferential side of waterproof sheet 1. Shotcrete 102, waterproof sheet 1, and lining concrete 103 are each laid around the entire periphery of the tunnel's inner circumferential surface.

[0021] Guard passages 104 are provided on both sides of the tunnel 100, and a substructure 105, such as a roadbed or a roadbed and invert concrete, is provided at the bottom of the tunnel 100. The substructure 105 is preferably installed in the tunnel 100 with a weight heavier than the design required so as to resist the buoyancy of the groundwater. The tunnel cross-sectional shape may be horseshoe-shaped, but a circular shape is preferable, and the circular tunnel cross-sectional shape has the advantages of making it easier to secure installation space for the dedicated water conduit 5 (described later), increasing resistance to water pressure, and facilitating installation when a substructure 105 heavier than the design required is required.

[0022] Dedicated water conduits 5 for conveying groundwater springs are installed inside the guard passages 104 on both sides, and the dedicated water conduits 5 are installed so as to extend in the longitudinal direction of the tunnel. In addition, drainage ditches 106 are installed on both the left and right sides of the lower structure 105, and a central water collection pipe 107 is installed in the center of the lower structure 105 in the width direction, and the drainage ditches 106 and central water collection pipe 107 are installed so as to extend in the longitudinal direction of the tunnel.

[0023] As shown in Figures 2 and 3(a), the waterproof sheet 1 is composed of an impermeable layer 2 made of EVA resin or the like, and a water-conducting layer 3 laminated on the outside of the impermeable layer 2, with the impermeable layer 2 and the water-conducting layer 3 being fixed together. The impermeable layer 2 and the water-conducting layer 3 may be fixed together directly, or they may be fixed together via a permeable intervening layer such as a nonwoven fabric to facilitate adhesion between the impermeable layer 2 and the water-conducting layer 3. The water-conducting layer 3 is dotted with support structures 4 that resist compression of the waterproof sheet 1 in the thickness direction. In this example, the support structures 4 are composed of a three-dimensional mesh formed by extruding a thermoplastic resin such as polypropylene and randomly spreading it into a planar shape to a predetermined thickness, or a three-dimensional mesh that has been locally compressed.

[0024] The water conducting layer 3 in the examples of Figures 2 and 3(a) is entirely made up of a three-dimensional network formed of linear resin or the like, and is therefore a water permeable layer with water permeability throughout. When the water conducting layer 3 is used as a water permeable layer, the water permeability coefficient is 10 -2 It is preferable to use a permeable layer with a permeability coefficient of 10 m / s or more. -1 It is more preferable to use a permeable layer with a permeability of at least m / s.

[0025] As another example, the waterproof sheet 1 may be replaced with a waterproof sheet 1a shown in FIG. 3(b). The waterproof sheet 1a is composed of an impermeable layer 2a made of EVA resin or the like and a water-conducting layer 3a laminated on the outside of the impermeable layer 2a, with the impermeable layer 2a and the water-conducting layer 3a being fixed together. In this example, the impermeable layer 2a and the water-conducting layer 3a may be fixed together directly, or they may be fixed together via a permeable intervening layer such as a nonwoven fabric to facilitate adhesion between the impermeable layer 2a and the water-conducting layer 3a. The water-conducting layer 3a is dotted with support structures 4a that resist compression in the thickness direction of the waterproof sheet 1a. In this example, the support structures 4a are composed of protrusions, and the protrusions are dotted around the water-conducting layer 3a.

[0026] The water conducting layer 3a in the example of FIG. 3(b) is made of a material that has a large number of water conducting channels evenly formed by forming unevenness on the entire surface, making it a water permeable layer that has water permeability throughout. -2 It is preferable to use a permeable layer with a permeability coefficient of 10 m / s or more. -1 It is more preferable to use a permeable layer with a permeability of at least m / s.

[0027] Box cutout sections 6 that can be closed with cover materials 7, such as mesh covers or plastic covers that are permeable to communication radio waves, are provided at predetermined locations on both sides of the lining concrete 103, and the box cutout sections 6 are arranged at multiple positions spaced apart in the longitudinal direction of the tunnel. A portion of a water intake pipe 8 and a measurement and drainage mechanism 50 are provided inside each box cutout section 6 (see Figures 1, 2, and 4), and as will be described later, the water intake pipe 8 and the water pressure gauge 30, pressure adjustment valve 40, and wireless communication unit 20 that make up the measurement and drainage mechanism 50 are each provided at multiple positions spaced apart in the longitudinal direction of the tunnel.

[0028] The intake pipe 8 is installed so as to penetrate the impermeable layer 2 and lining concrete 103 of the waterproof sheet 1 and reach the water conveying layer 3. In this example, the end of the intake pipe 8 is attached to the impermeable layer 2 by a drain flange 81. If a permeable intermediate layer such as nonwoven fabric is interposed between the impermeable layer 2, 2a and the water conveying layer 3, 3a, the drain flange 81 is attached to the permeable intermediate layer, and the intake pipe 8 is installed so as to penetrate the permeable intermediate layer such as nonwoven fabric. The intake pipe 8 is installed so as to extend through the inside of the box cutout section 6, the surface of the lining concrete 103, and the inside of the monitor's passage 104 to the dedicated water conveying pipe 5. It takes in water outside the waterproof sheet 1, in other words, spring water that has formed inside the shotcrete 102, and discharges the taken water into the dedicated water conveying pipe 5 for drainage.

[0029] The measurement and drainage mechanism 50 is composed of a wireless communication unit 20, a water pressure gauge 30, and a pressure regulating valve 40 (see Figures 2 and 4). The water pressure gauge 30 is provided in the water intake pipe 8 inside the lining concrete 103, and in this example, is attached to the water intake pipe 8 inside the box-out section 6. The pressure regulating valve 40 opens and closes according to the water pressure data measured by the water pressure gauge 30, and is provided in the water intake pipe 8 downstream of the water pressure gauge 30, and in this example, is provided in the water intake pipe 8 inside the box-out section 6 downstream of the water pressure gauge 30.

[0030] The wireless communication unit 20 is configured to communicate wirelessly with the drainage control device 10, and includes a control unit 21 that executes predetermined processing according to a control program, a memory unit 22 that stores the control program in a control program storage unit 221, a wireless communication unit 23 that handles wireless communication, and an input / output interface 24. The water pressure gauges 30 and pressure regulating valves 40 that constitute the same measurement and drainage mechanism 50 together with the wireless communication unit 20 are communicably connected to the wireless communication unit 20 via the input / output interface 24. The wireless communication unit 20 transmits measured water pressure data of the corresponding water pressure gauges 30 to the drainage control device 10, and opens and closes the corresponding pressure regulating valves 40 in response to valve opening / closing signals received from the drainage control device 10.

[0031] As shown in Figure 4, the drainage control device 10 includes a control unit 11 such as an MPU or CPU, a memory unit 12 consisting of an HDD, SSD, flash memory, EEPROM, ROM, RAM, etc., an input unit 13 such as a touch panel, mouse, keyboard, etc., a display unit 14 such as a touch panel or display that also serves as the input unit 13, a timer 15, and a wireless communication unit 16 that handles wireless communication.

[0032] The drainage control device 10 communicates wirelessly via the wireless communication section 16 with each of the wireless communication units 20 arranged at a plurality of locations, and receives water pressure measurement data of the water pressure gauge 30 from each of the wireless communication units 20, and transmits valve opening / closing signals to each of the wireless communication units 20. The drainage control device 10 also communicates wirelessly via the wireless communication section 16 with a water volume sensor 60 with wireless communication capabilities that is provided at a location where all the water is collected, such as the downstream end of a water collection pipe 61 that collects water flowing through the dedicated water pipe 5.

[0033] The memory unit 12 of the drainage control device 10 has a control program storage unit 121 in which predetermined control programs including a drainage control program and a management processing program are stored, and the control unit 11 executes predetermined processing as a drainage control unit 111 in accordance with the drainage control program and executes predetermined processing as a management processing unit 112 in accordance with the management processing program.

[0034] The memory unit 12 has a threshold storage unit 122 that stores a drainage start threshold Pα and a drainage stop threshold Pβ in a configurable manner, and a management information recording unit 123 that stores management information. The management information recorded in the management information recording unit 123 includes, for example, information in which the measured water pressure data of the water pressure gauge 30 received from each of the wireless communication units 20 at multiple locations is recorded in chronological order in association with the position identification information of each wireless communication unit 20 or each measurement and drainage mechanism 50, information in which the valve opening / closing signal transmitted in response to the valve opening / closing determination process by the drainage control unit 111 is recorded in association with the position identification information of each wireless communication unit 20 or each measurement and drainage mechanism 50 and the date and time of transmission, and information in which the drainage control device 10 records the integrated flow rate over a predetermined period of time obtained by integrating the water volume data continuously received by the drainage control device 10 from the water volume sensor 60 with wireless communication function.

[0035] When performing drainage control processing with the tunnel water pressure adjustment device of this embodiment, as shown in Figure 5, the wireless communication unit 20 of each measurement and drainage mechanism 50 continuously acquires the measured water pressure data Pn of the corresponding water pressure gauge 30, and continuously transmits the measured water pressure data of the water pressure gauge 30 together with the location identification information of the measurement and drainage mechanism 50 or the wireless communication unit 20 to the drainage control device 10 (S101).

[0036] The drainage control device 10 continuously receives the measured water pressure data Pn of the water pressure gauge 30 and the position identification information transmitted from the wireless communication unit 20 of each measurement and drainage mechanism 50 (S102), and the drainage control unit 111 of the drainage control device 10 executes a valve opening / closing determination process for the measurement and drainage mechanism 50 or its pressure regulating valve 40 corresponding to the position identification information by comparing the measured water pressure data Pn with the drainage start threshold value Pα and the measured water pressure data Pn with the drainage stop threshold value Pβ (S103), and transmits a valve open signal or a valve close signal to the wireless communication unit 20 of the measurement and drainage mechanism 50 corresponding to the position identification information depending on the valve opening / closing determination result (S104).

[0037] In the valve opening / closing determination process performed by the drainage control unit 111, the measured water pressure data Pn received from the water pressure gauge 30 is compared with the drainage start threshold Pα, and if it is determined that the measured water pressure data Pn exceeds the drainage start threshold Pα or is equal to or greater than the drainage start threshold Pα, a valve open signal is sent to the wireless communication unit 20. Also, if it is determined that the measured water pressure data Pn received from the water pressure gauge 30 is compared with the drainage stop threshold Pβ, or is equal to or less than the drainage stop threshold Pβ, a valve close signal is sent to the wireless communication unit 20. The drainage stop threshold Pβ is set to a water pressure value that is a predetermined amount smaller than the drainage start threshold Pα, and is set, for example, as drainage stop threshold Pβ = drainage start threshold Pα × 0.9.

[0038] In setting the drainage start threshold Pα, for example, a numerical analysis that couples water and stress is used during tunnel design to calculate the stress generated in the lining due to the action of groundwater pressure, taking into account the groundwater level and permeability coefficient of the natural ground 101, and the lining structure, such as the thickness of the lining concrete 103, is determined, and the water pressure is set so that it remains within the range of the lining structure's bearing capacity. Note that if a waterproof sheet is used with a water-conducting layer made of nonwoven fabric or the like without scattered support structures such as support structures 4, 4a, the pressing force from the inside of the tunnel to the outside due to the pouring of the lining concrete and the pressing force from the outside to the inside due to the pore water pressure in the ground will cause scattered crushed areas in the water-conducting layer made of nonwoven fabric or the like, making it difficult to stably convey water to the position of the water intake pipe 8, making it difficult to set an appropriate drainage start threshold Pα and drainage stop threshold Pβ.

[0039] The drainage control unit 111's valve opening / closing determination process and valve opening / closing signal transmission process may be executed, for example, in a valve opening detection processing mode, by comparing the received measured water pressure data Pn of the water pressure gauge 30 only with the drainage start threshold Pα, and if it is determined that the measured water pressure data Pn exceeds the drainage start threshold Pα or is equal to or greater than the drainage start threshold Pα, sending a valve opening signal to the wireless communication unit 20 and switching to a valve closing detection processing mode; and in a valve closing detection processing mode, by comparing the received measured water pressure data Pn of the water pressure gauge 30 only with the drainage stop threshold Pβ, and if it is determined that the measured water pressure data Pn is less than the drainage stop threshold Pβ or is equal to or less than the drainage stop threshold Pβ, sending a valve closing signal to the wireless communication unit 20 and switching to a valve opening detection processing mode; and the pressure regulating valve 40 opened by a valve opening signal may remain open until a valve closing signal is received, and the pressure regulating valve 40 closed by a valve closing signal may remain closed until a valve opening signal is received.

[0040] As another example of the valve opening / closing determination process and valve opening / closing signal transmission process of the drainage control unit 111, a process of comparing the received measured water pressure data Pn from the water pressure gauge 30 with both the drainage start threshold Pα and the drainage stop threshold Pβ is constantly executed, and if the measured water pressure data Pn is determined to be above the drainage start threshold Pα or equal to or greater than the drainage start threshold Pα, a valve open signal is constantly transmitted to the wireless communication unit 20, and if the measured water pressure data Pn is determined to be below the drainage stop threshold Pβ or equal to or less than the drainage stop threshold Pβ, a valve close signal is constantly transmitted to the wireless communication unit 20, so that the pressure regulating valve 40 is maintained in an open state by the valve open signal received at all times until a valve close signal is received, and the pressure regulating valve 40 is maintained in a closed state by the valve close signal received at all times until a valve open signal is received.

[0041] The wireless communication unit 20 of the measurement and drainage mechanism 50 corresponding to the position identification information for which the valve open / close determination was made receives a valve open signal or a valve close signal from the drainage control device 10 (S105), and the control unit 21 of the wireless communication unit 20 executes a valve open control process for the corresponding pressure regulating valve 40 in response to receiving the valve open signal to open the pressure regulating valve 40, and executes a valve close control process in response to receiving the valve close signal to close the pressure regulating valve 40 (S106). When the pressure regulating valve 40 is opened, ground spring water outside the waterproof sheet 1 is drained into the dedicated water conduit 5 via the water intake pipe 8, and when the pressure regulating valve 40 is closed, drainage of ground spring water via the water intake pipe 8 into the dedicated water conduit 5 is stopped.

[0042] In addition, the management processing unit 112 of the drainage control device 10 records the measured water pressure data Pn of the water pressure gauge 30 received from each of the wireless communication units 20 of the measurement and drainage mechanisms 50 at each location in chronological order in the management information recording unit 123, corresponding it to the position identification information of each wireless communication unit 20 or each measurement and drainage mechanism 50, and also records the valve open signal or valve close signal transmitted in response to the valve opening / closing determination process by the drainage control unit 111 in chronological order in the management information recording unit 123, corresponding it to the position identification information of each wireless communication unit 20 or each measurement and drainage mechanism 50 and the date and time of transmission.

[0043] Furthermore, the management processing unit 112 of the drainage control device 10 in this embodiment continuously receives water volume data detected by the water volume sensor 60 with wireless communication function, which is installed at a point in the water collection pipe 61 that collects the water flowing through the multiple dedicated water pipes 5, where all of the water flowing through these multiple dedicated water pipes 5 is collected, calculates the accumulated flow rate for a predetermined period of time by accumulating the received water volume data, and records the calculated accumulated flow rate in the management information recording unit 123.

[0044] According to the tunnel water pressure regulating device of this embodiment, support structures 4, 4a that resist compression in the thickness direction are provided so as to be scattered on the water conducting layers 3, 3a of the waterproof sheets 1, 1a, or the support structures 4, 4a are provided so as to be scattered in a substantially uniform or similar manner throughout the water conducting layers 3, 3a, thereby ensuring gaps that allow water to flow smoothly into the water conducting layers 3, 3a. Therefore, when the pressure regulating valve 40 is used to drain groundwater and adjust the water pressure applied to the outside of the waterproof sheets 1, 1a, water can be smoothly drained up to the intake position of the water intake pipe 8 where the pressure regulating valve 40 is installed, reliably eliminating the condition in which excessive water pressure is applied unevenly to the lining concrete 103.

[0045] The water conducting layers 3 and 3a are made of a material having a permeability coefficient of 10 -2 The permeable layer should be more than m / s, and more preferably, the permeability coefficient should be 10 -1 In the case of a permeable layer of at least m / s, water can be discharged by flowing more smoothly up to the intake position of the intake pipe 8 where the pressure regulating valve 40 is provided.

[0046] Furthermore, since the water taken in by the intake pipe 8 is spring water generated from the natural ground 101, by discharging it from the intake pipe 8 into the dedicated water conduit 5, it can be distinguished from wastewater generated by construction work within the tunnel space that requires purification treatment, and the natural ground spring water can be ultimately discharged into a river or the natural ground 101, etc., via the dedicated water conduit 5 without purification treatment. In other words, economical wastewater treatment can be carried out while taking into consideration the environmental load.

[0047] Furthermore, for example, if the overall thickness of the lining concrete is increased to resist the buoyancy of the groundwater, the cross section of the tunnel excavation will become larger and construction costs will increase significantly. However, as shown in Figure 6, if a lower structure 105 that is heavier than the design required weight is provided in tunnel 100 and the internal load F1 of the lower structure 105 is used to resist the buoyancy F2 of the groundwater, the impact of the buoyancy F2 of the groundwater on tunnel 100 can be reduced while reducing construction costs.

[0048] Furthermore, the drainage control device 10 executes a valve opening / closing determination process, and sends a valve open signal to the wireless communication unit 20 of the measuring and draining mechanism 50 when it determines that the measured water pressure data Pn of the water pressure gauge 30 exceeds the drainage start threshold Pα or is equal to or greater than the drainage start threshold Pα, and sends a valve close signal to the wireless communication unit 20 of the measuring and draining mechanism 50 when it determines that the measured water pressure data Pn of the water pressure gauge 30 is less than the drainage stop threshold Pβ or is equal to or less than the drainage stop threshold Pβ, thereby enabling the necessary opening and closing operations of the pressure control valve 40 to be performed automatically without relying on manual opening and closing operations of the pressure adjustment valve. Furthermore, by storing the drainage start threshold Pα and the drainage stop threshold Pβ in a configurable manner in the drainage control device 10, which wirelessly communicates with the wireless communication unit 20 corresponding to the pressure adjustment valve 40, the drainage start threshold Pα and the drainage stop threshold Pβ appropriate for water pressure adjustment can be flexibly set in a location remote from the wireless communication unit 20 of the measuring and draining mechanism 50.

[0049] Furthermore, one drainage control device 10 can be responsible for controlling the opening and closing operations of the pressure adjustment valves 40 of each of the metering and drainage mechanisms 50 installed in multiple locations, and if, for example, there is a change in the values ​​of the drainage start threshold Pα and the drainage stop threshold Pβ appropriate for water pressure adjustment, each pressure control valve 40 can be easily made to perform the appropriate opening and closing operation by changing the drainage start threshold Pα and the drainage stop threshold Pβ of the drainage control device 10. Furthermore, the pressure adjustment valves 40 of each of the metering and drainage mechanisms 50 can be flexibly opened and closed according to the water pressure conditions at each of the multiple locations along the tunnel longitudinal direction.

[0050] Furthermore, the drainage control device 10 can record the time-series measured water pressure data Pn from each water pressure gauge 30 of the measuring and drainage mechanisms 50 at multiple positions and the open / close status of the pressure regulating valves 40 at each position as management information in the management information recording unit 123, and use this as maintenance data. Furthermore, in normal tunnel maintenance, the condition of the lining concrete 103 and the amount of displacement of the internal cross section are monitored to evaluate the soundness, but the measured water pressure data Pn from the water pressure gauge 30, which corresponds to the water pressure acting on the lining concrete 103, can be added to the monitoring items, allowing for a more accurate evaluation of the tunnel soundness.

[0051] Furthermore, the drainage control device 10 continuously receives water volume data from the water volume sensor 60 with wireless communication function and records the accumulated flow rate for a specified period of time obtained by accumulating the received water volume data in the management information recording unit 123.This makes it possible to add both the measured water pressure data Pn of the water pressure meter 30, which corresponds to the water pressure acting on the lining concrete 103, and the accumulated flow rate of spring water from the natural ground 101 for a specified period of time to the monitoring items, thereby enabling a more accurate evaluation of the tunnel healthiness.

[0052] In urban areas, watertight sections are sometimes set up due to the environmental conditions above the tunnel. However, if the adjacent drainage section is long, it becomes necessary to install pumping equipment in shafts in urban areas to pump large amounts of spring water up to near the surface, resulting in problems such as high construction costs and tunnel maintenance costs, such as high drainage treatment costs. However, the tunnel waterproofing specifications equipped with the tunnel water pressure adjustment device of this embodiment make it possible to prevent groundwater from being drained to the extent that the tunnel structure is not damaged, while performing drainage treatment and drainage control when excessive water pressure is applied, thereby reducing tunnel construction costs and tunnel maintenance costs. Furthermore, this tunnel waterproofing specification provides a new option for tunnel waterproofing specifications, compared to the conventional two-choice tunnel waterproofing specifications: drainage, which has cost benefits but is concerned about the impact on the groundwater environment, and watertight, which can preserve the groundwater environment but significantly increases costs and reduces workability.

[0053] Furthermore, in the tunnel waterproofing specifications in which the tunnel water pressure adjustment device of this embodiment is installed, by normally not draining the water and draining the water by opening the pressure adjustment valve 40 to the extent necessary, it is possible to promote tunnel construction projects in, for example, scenic areas, environmental conservation areas with rare flora and fauna, and areas where groundwater is used for agriculture, industry, etc. Furthermore, it is possible to minimize changes to the groundwater environment caused by tunnel construction while reducing loosening of the ground 101 caused by ground spring water remaining outside the waterproof sheets 1, 1a, thereby extending the lifespan of the tunnel structure.

[0054] [Scope of the invention disclosed herein] The inventions disclosed in this specification include, in addition to the individual inventions and embodiments listed as inventions, those specified by changing partial contents of these to other contents disclosed in this specification, those specified by adding other contents disclosed in this specification to these contents, or those specified by deleting partial contents of these to the extent that partial effects are obtained and creating a generic concept.The inventions disclosed in this specification also include the following contents and modifications.

[0055] For example, the water conducting layer 3a of the waterproof sheet 1a in the above embodiment is entirely made of a mesh material or the like, and is a permeable layer that is permeable throughout, but the material that forms the water conducting layer 3a itself can also be an impermeable layer, and the protrusions of the support structure 4a can be connected in a lattice pattern to provide scattered permeable areas.The water conducting layer in the present invention can also be an impermeable layer if it is configured so that water can be taken from outside the waterproof sheet by a water intake pipe that is installed to penetrate the impermeable layer and the lining concrete and reach the water conducting layer.

[0056] In addition, the tunnel water pressure adjustment device of the present invention includes a water pressure gauge installed in the water intake pipe inside the lining concrete, and a pressure adjustment valve installed in the water intake pipe downstream of the water pressure gauge and opened and closed according to the measured water pressure data of the water pressure gauge.For example, instead of a configuration in which the drainage control device 10 performs the valve opening / closing judgment process and sends the valve opening / closing signal, it is also possible to configure the measurement and drainage mechanism 50 to have a drainage control unit consisting of a CPU or the like and a memory unit for storing control programs and thresholds, and this drainage control unit performs valve opening / closing judgment process by comparing the measured water pressure data Pn of the water pressure gauge 30 with the drainage start threshold Pα and the drainage stop threshold Pβ, and the drainage control unit performs valve opening / closing control process on the pressure adjustment valve 40 according to the judgment result. [Industrial Applicability]

[0057] The present invention can be used to adjust the water pressure applied to the outside of a waterproof sheet laid on the outside of a tunnel lining concrete. [Explanation of symbols]

[0058] 1, 1a... Waterproof sheet 2, 2a... Impermeable layer 3, 3a... Water conveyance layer 4, 4a... Support structure 5... Dedicated water conveyance pipe 6... Box cutout section 7... Cover material 8... Water intake pipe 81... Water drain flange 10... Drainage control device 11... Control section 111... Drainage control section 112... Management processing section 12... Memory section 121... Control program storage section 122... Threshold value storage section 123... Management information recording section 13... Input section 14... Display section 15... Timer 16... Wireless communication section 20... Wireless communication unit 21... Control section 22... Memory section 221... Control program storage section 23... Wireless communication section 24... Input / output interface 30... Water pressure gauge 40... Pressure control valve 50... Measuring and drainage mechanism 60... Water volume sensor with wireless communication function 61... Water collection pipe 100... Tunnel 101... Natural ground 102... Shotcrete 103...Lining concrete 104...Watchman passage 105...Substructure 106...Drainage ditch 107...Central water collection pipe 200...Drainage type tunnel 201...Lining concrete 202...Arch section 203...Side wall section 204...Waterproof sheet 205...Water collection material 206...Central water collection pipe 300...Watertight type tunnel 301...Lining concrete 302...Waterproof sheet 303...Multi-reinforced steel structure GL...Ground surface WL...Groundwater level F1...Internal load F2...Buoyancy of groundwater

Claims

1. A tunnel water pressure adjusting device that adjusts the water pressure applied to the outside of a waterproof sheet laid on the outside of a tunnel lining concrete, The waterproof sheet is composed of an impermeable layer and a water-conducting layer laminated on the outside of the impermeable layer, and the water-conducting layer is provided with support structures interspersed therein that resist compression in the thickness direction; A water intake pipe that penetrates the impermeable layer and the lining concrete to reach the water conveyance layer and takes in water outside the waterproof sheet; a water pressure gauge provided on the intake pipe inside the lining concrete; A tunnel water pressure regulating device characterized by comprising a pressure regulating valve that is provided in the water intake pipe downstream of the water pressure gauge and that opens and closes in accordance with the water pressure data measured by the water pressure gauge.

2. The water conducting layer has a hydraulic conductivity of 10 －２ 2. A tunnel water pressure adjusting device according to claim 1, characterized in that the tunnel water pressure adjusting device is a permeable layer having a water permeability of at least m / s.

3. 2. A tunnel water pressure adjusting device according to claim 1, wherein the water intake pipe discharges the water taken in to a dedicated water conduit extending in the longitudinal direction of the tunnel.

4. 2. A tunnel water pressure adjusting device according to claim 1, wherein a substructure heavier than the design required weight is installed in the tunnel to resist the buoyancy of the groundwater.

5. a wireless communication unit that transmits the water pressure measured by the water pressure gauge and opens and closes the pressure regulating valve in response to a valve opening / closing signal; a drainage control device that receives water pressure measurement data of the water pressure gauge from the wireless communication unit and transmits a valve opening / closing signal to the wireless communication unit, A tunnel water pressure regulating device as described in any one of claims 1 to 4, characterized in that the drainage control device stores a drainage start threshold and a drainage stop threshold in a configurable manner, performs a valve opening / closing judgment process, and sends a valve open signal to the wireless communication unit if it judges that the measured water pressure data received from the water pressure gauge exceeds the drainage start threshold or is equal to or greater than the drainage start threshold, and sends a valve close signal to the wireless communication unit if it judges that the measured water pressure data received from the water pressure gauge is less than the drainage stop threshold or is equal to or less than the drainage stop threshold.

6. The water intake pipe, the water pressure gauge, the pressure regulating valve, and the wireless communication unit are provided at each of a plurality of positions spaced apart in the longitudinal direction of the tunnel, The tunnel water pressure regulating device described in claim 5, characterized in that the drainage control device receives measured water pressure data of the water pressure gauge from each of the wireless communication units at the multiple locations, performs a valve opening / closing determination process for each of the multiple locations, and transmits a valve opening / closing signal to each of the wireless communication units in accordance with the valve opening / closing determination process.

7. The tunnel water pressure regulating device described in claim 6, characterized in that the drainage control device records the measured water pressure data of the water pressure gauge received from each of the wireless communication units at the multiple locations in a chronological order in a management information recording unit in correspondence with location identification information, and records a record of the valve opening / closing signal transmitted in response to the valve opening / closing determination process in correspondence with the location identification information and the date and time of transmission in the management information recording unit.

8. The intake pipe drains the water taken into a dedicated water pipe extending in the longitudinal direction of the tunnel, a water volume sensor with a wireless communication function is provided at a location where the entire water is collected in a water collection pipe that collects the water flowing through the dedicated water pipe; The tunnel water pressure regulating device described in claim 7, characterized in that the drainage control device continuously receives water volume data from the water volume sensor with wireless communication function, and records the integrated flow rate over a predetermined period of time obtained by accumulating the received water volume data in the management information recording unit.

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