JP6130728B2 - Concrete height measuring device and method for constructing lining concrete - Google Patents

Description

  The present invention relates to a concrete height measuring device for measuring the height of concrete placed in a lining space between a tunnel inner peripheral surface and a mold frame opposed thereto, and lining concrete using the same. It relates to the construction method.

  In mountain tunnels, etc., a method using a formwork called a lining centle is generally adopted as a method for forming lining concrete constructed to cover the ground of the inner peripheral surface of the excavated tunnel. Yes.

  In this construction method, concrete placement is generally performed on the left and right tunnel side walls and arch-shaped portions in the lining space between the tunnel inner peripheral surface and the mold opposite to it. This is done by inserting pipes into inspection windows or the like provided in the left and right molds, respectively, and pumping concrete.

  As a method of forming lining concrete using this type of formwork, the method described in Patent Document 1 is known. In this Patent Document 1, a plurality of pressure sensors are provided on the surface of the lining concrete side of the formwork at intervals in the circumferential direction, and the pressure at each point is measured and placed in the lining space. A technique for managing the filling properties of concrete is disclosed.

JP 2011-184934 A

  Here, in the method of forming lining concrete using this type of formwork, when concrete is placed on the left and right tunnel side walls and arch-shaped parts, the height of the concrete is monitored. There is a need. In other words, the concrete launch height is an important parameter in construction management.

  However, in the technique described in Patent Document 1, the pressure at each point is only managed by placing a pressure sensor at a predetermined height with an interval in the circumferential direction of the formwork. Therefore, with this technology, it is only possible to detect whether concrete has been launched to a height corresponding to each predetermined point, and to measure to what height concrete has been launched at an arbitrary time. Can not. In addition, it is conceivable to increase the detection accuracy of the launch height by increasing the number of places where the pressure sensor is installed, but in this case, the cost of the sensor and the cost of wiring construction increase.

  The present invention has been made paying attention to such a situation, and provides a concrete height measuring device capable of measuring the concrete launch height with a simple configuration and a method for constructing lining concrete using the same. The purpose is to do.

  In response to the above-described problem, the concrete height measuring device according to the present invention has, as one aspect thereof, a concrete launching operation to be placed in a lining space between a tunnel inner peripheral surface and a formwork opposed thereto. A concrete height measuring apparatus for measuring height, wherein the pair of conductive wires are supported along the inner peripheral surface of the tunnel and supported by the inner peripheral surface of the tunnel, and are electrically insulated from each other, and the pair of conductive wires And a main body for measuring the height of the concrete based on the capacitance between the two.

  Moreover, the concrete height measuring apparatus according to the present invention, as another aspect, determines the height of the concrete to be placed in the lining space between the inner peripheral surface of the tunnel and the formwork opposed thereto. A concrete height measuring device for measuring, extending in the vertical direction along the inner surface of the end form frame that closes the end of the lining space in the tunnel axis direction, supported by the end form frame, and mutually A pair of electrically insulated conductors; and a main body that measures a height of the concrete based on a capacitance between the pair of conductors.

  Moreover, the construction method of the lining concrete which concerns on this invention uses the measurement result of the concrete height measuring apparatus of said another one aspect | mode as one aspect | mode, and casts concrete in the said lining space and covers it. A lining concrete construction method for constructing work concrete, wherein the pair of electric wires supported by the wife formwork together with the wife formwork closing the end of the preceding lining space in the tunnel axial direction. Removing the conductive wire, and moving the formwork forming the preceding lining space in the tunnel axial direction, and setting the succeeding lining space adjacent to one end surface of the preceding lining concrete in the tunnel axial direction. The step of forming and the end of the subsequent lining space opposite to the preceding lining concrete side are closed by the wife mold and the pair of conductive wires are attached to the inner surface of the wife mold Craft When, and a step of constructing a subsequent lining concrete by Da設 concrete into the subsequent lining space.

  According to the concrete height measuring apparatus according to the present invention, it extends in the vertical direction along the inner peripheral surface of the tunnel and the inner surface of the end form, and is electrically insulated from each other by being supported by the inner peripheral surface of the tunnel and the end form. Since the concrete height is measured on the basis of the capacitance between the pair of conductive wires, the concrete changes using the fact that the capacitance changes as the concrete height increases. The launch height can be measured. In addition, a sensor for measuring the concrete launch height can be continuously arranged on the inner peripheral surface of the tunnel or the inner surface of the wife formwork. For this reason, it is possible to measure to what height concrete has been launched at an arbitrary time. That is, it is possible to detect the launch height continuously. In addition, the sensor for measuring the concrete launch height simply extends a pair of conductive wires that are electrically insulated from each other along the inner peripheral surface of the tunnel or the inner surface of the end formwork. Compared with the prior art provided with a plurality of sensors, the cost of the sensor and the cost of wiring construction can be suppressed. In this way, it is possible to provide a concrete height measuring apparatus capable of measuring the concrete launch height with a simple configuration.

  In addition, since the pair of conductive wires are provided on the inner peripheral surface of the tunnel and the wife formwork, the inner surface of the lining concrete is compared with the conventional technique in which the pressure sensor is provided on the lining space side of the formwork. Surface finish can be improved.

  Furthermore, when providing a pair of conductive wires on the inner surface of the end formwork (surface on the concrete to be placed), after constructing the lining concrete, the pair of conductive lines can be removed when the end formwork is removed. Therefore, the pair of conductive wires can be reused for construction of subsequent lining concrete or the like.

According to the one aspect of the method for constructing lining concrete according to the present invention, the lining concrete can be constructed using the measurement result of the concrete height measuring device according to the other aspect, so that any It is possible to monitor how high the concrete is launched in time and perform precise construction management, which in turn can improve the quality of the lining concrete.
In addition, after the construction of the preceding lining concrete, the process includes removing the end formwork from the preceding lining concrete and removing the pair of conductive wires supported by the end formwork. When constructing a subsequent lining concrete by adding concrete to the lining concrete, attach the removed pair of conductive wires to the inner surface of the wife formwork that closes the end of the subsequent lining space and reuse it. Can do.

It is a figure for demonstrating schematic structure of the concrete height measuring apparatus which concerns on 1st Embodiment of this invention. It is AA sectional drawing of FIG. It is a top view of the formwork seen from the B arrow direction shown in FIG. It is a figure which shows the state which attached and fixed the pair of electrical wire to the inner surface of a wife formwork, and is an enlarged view of the C section shown in FIG. It is a figure which shows the measurement result of a concrete height measuring apparatus, A horizontal axis is time t and a vertical axis | shaft is launch height H. It is a figure for demonstrating schematic structure of the concrete height measuring apparatus which concerns on 2nd Embodiment of this invention. It is DD sectional drawing of FIG. It is a top view of the formwork seen from the E arrow direction shown in FIG. It is a figure which shows the state which attached and fixed a pair of electrically conductive wire to the tunnel internal peripheral surface, and is an enlarged view of the F section shown in FIG.

Hereinafter, an embodiment of a concrete height measuring apparatus according to the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a diagram showing a schematic configuration of a concrete height measuring device 100 according to a first embodiment of the present invention, and shows a case where it is applied to the construction of lining concrete for a mountain tunnel. FIG. 1 is also a cross-sectional view of the tunnel viewed from the face side (wife side). FIG. 2 is a cross-sectional view taken along the line AA of FIG. In FIG. 2, a gantry vehicle 7 described later is omitted for simplification of the drawing. FIG. 3 is a plan view of the mold 4 seen from the direction of arrow B shown in FIG. In the present embodiment, the traveling direction of the tunnel lining means a direction from the wellhead side (lap side) toward the face side (wife side) along the tunnel axis direction.

  The tunnel of the present embodiment is a mountain tunnel, and spray concrete 2 is sprayed and primarily supported on the inner peripheral surface 1 of the tunnel formed by blasting excavation or the like, and a waterproof sheet 3 (see FIG. 9 described later) is provided thereon. It is pasted inside. Then, a mold frame 4 having an arch-shaped outer peripheral surface is set to face the tunnel inner peripheral surface 1 (waterproof sheet 3) and covered between the tunnel inner peripheral surface 1 (waterproof sheet 3) and the mold frame 4. A lining space S for laying concrete is formed. For setting the mold 4, a gantry vehicle 7 that can move on a rail 6 laid on the tunnel bottom surface 5 along the tunnel axis direction is used.

  The concrete height measuring device 100 measures the height of the concrete that is placed in the lining space S between the inner circumferential surface 1 of the tunnel and the mold 4 opposed to the inner peripheral surface 1. The electric wires 101a and 101b and the main body 102 are provided.

The pair of conductive wires 101a and 101b serve as sensors for measuring the concrete launch height, and are extended while being electrically insulated from each other.
In the present embodiment, the pair of conductive wires 101a and 101b are provided on the left and right sides of the tunnel (tunnel width direction), respectively. In the following, when it is not necessary to distinguish between the “left pair of conductive wires 101a and 101b” and the “right pair of conductive wires 101a and 101b”, they are simply referred to as “a pair of conductive wires 101a and 101b”, respectively.

  As shown in FIG. 1, each of the pair of conductive wires 101a and 101b has one end connected to the main body 102 and the other end positioned in a tunnel crown Sc described later. The other ends of the pair of conductive wires 101a and 101b are also electrically insulated from each other. One conductive wire 101a is, for example, a conductive wire rope having an outer diameter of 2 mm, and the outer periphery thereof is covered with vinyl 101c (outer diameter of 4 mm) as an electrically insulating material as shown in FIG. Thus, it is electrically insulated from the other conductive wire 101b. The other conductive wire 101b is, for example, a conductive wire rope having an outer diameter of 4 mm and serves as a ground wire. The other conductive wire 101b and the one conductive wire 101b are appropriately bundled together with one conductive wire 101b by a vinyl tape or the like so that the outer periphery of the conductive wire 101b and the outer periphery of the vinyl 101c of the one conductive wire 101a are in contact with each other. In this way, by forming a sensor for measuring the concrete launch height with the pair of conductive wires 101a and 101b and the covering vinyl 101c, the sensor can be easily reshaped according to the shape of the laying path. . Further, by bundling the other conductive wire 101b together with one conductive wire 101a covered with the electrically insulating material (101c), electrical insulation between the pair of conductive wires 101a and 101b can be easily realized. By using the bundled pair of conductive wires 101a and 101b, the distance between one conductive wire 101a and the other conductive wire 101b can be easily made constant. In addition, the installation location and the installation method of the pair of conductive wires 101a and 101b will be described in detail later.

  The main body portion 102 measures the height of concrete that is placed in the lining space S based on the capacitance between the pair of conductive wires 101a and 101b. is set up. One end of a pair of conductive wires 101a and 101b on the left side of the tunnel is connected to the main body 102, and one end of a pair of conductive wires 101a and 101b on the right side of the tunnel is connected to the main body 102, respectively. Thereby, it is comprised so that the concrete launch height of each right and left of a tunnel can be measured separately. In FIG. 1, the wiring between the pair of conductive wires 101a and 101b on the right side and the main body 102 is omitted for simplification of the drawing. In addition, the main-body part 102 can be installed not only in the tunnel bottom face 5 but in an appropriate place, for example, may be installed on the gantry vehicle 7. Further, the measurement principle of the launch height will be described in detail later.

  The mold 4 is also referred to as a “lining centile”, and as shown in FIG. 2 and FIG. 3, which is a plan view of the mold 4 seen from the direction of arrow B shown in FIG. A plurality of (for example, seven) formwork members having a predetermined width (for example, 1.5 m) are connected in the tunnel axis direction to form one span (for example, 10.5 m). Each formwork member is appropriately divided in the circumferential direction as shown in FIG. 1 and used in combination. In FIG. 3, for the sake of simplification of the drawing, the dividing boundary in the circumferential direction of the mold 4 is not shown.

  As shown in FIGS. 2 and 3, for example, a seven-span mold 4 is constituted by seven mold members 4A to 4G in the tunnel axis direction, and the tunnel inner peripheral surface 1 and a one-span mold 4 (4A to 4G) are formed. ), A lining space S for laying concrete is formed. As shown in FIG. 1, the lining space S includes left and right tunnel side wall portions (tuning space on the tunnel side wall portions) Sa, Sa, and subsequent left and right arch shape portions (covering arch shape portions). Space) Sb, Sb and a central tunnel crown (tunnel lining space) Sc. In the lining space S, the concrete is placed on the left and right tunnel side walls Sa, Sa and the arch-shaped portions Sb, Sb by placing concrete placing pipes (not shown) installed in the gantry vehicle 7 on the left and right sides. This is performed by inserting concrete into the lining space S (Sa, Sb) through inspection windows (not shown) provided at appropriate heights in the center of the tunnel 4 in the tunnel axial direction. Thereafter, a concrete placement pipe (not shown) is connected to a placement hole appropriately formed at a position corresponding to the tunnel crown portion Sc in the center in the tunnel axis direction of the mold 4 to pump the concrete, and the tunnel crown portion Sc. Concrete is placed on the ground. As concrete to be cast, for example, medium fluidity concrete having high fluidity may be used. Thereby, the filling property of the concrete into the lining space S can be improved, and the finish of the surface of the lining concrete can be improved. In addition, the position and number of the inspection window and the placement hole can be determined as appropriate.

  In addition, as shown in FIG. 2, the end portion (lap side) in the tunnel axis direction of the lining space S is closed by existing (preceding) lining concrete 8. On the other hand, the face side end (wife side) in the tunnel axis direction of the lining space S (Sa, Sb, Sc) is closed by a closing mold 9. The end form 9 is also called a “sheet pile” and is appropriately divided in the circumferential direction and used in combination. For example, the end form 9 is made of wood having a thickness of about 25 to 30 mm. In FIG. 1 and FIG. 3, for the sake of simplification, the division boundary in the circumferential direction of the wife form frame 9 is not shown.

The gantry vehicle 7 is a portal-type movable carriage that can travel in the tunnel axis direction, has a predetermined length in the tunnel axis direction, and has front and rear ends (tunnel axis direction ends) as shown in FIG. A self-propelled device 72 that moves on the rail 6 is provided at the lower end of the leg portion 71. Further, jacks 73 to 76 are attached to the gantry vehicle 7. Each mold member 4 divided in the circumferential direction is connected and fixed to the gantry wheel 7 via these jacks 73 to 76.
In addition, each of the leg portions 71 located in the middle of the tunnel axis direction of the gantry vehicle 7 is provided with an auxiliary jack 77 (see FIG. 6 described later) at the lower end. The auxiliary jack 77 restricts the movement of the gantry vehicle 7 when the gantry vehicle 7 is stopped. Further, an inner space 70 is formed inside the gantry vehicle 7 so that the work vehicle can easily pass in the tunnel axis direction. Further, the gantry vehicle 7 is provided with a pipe (not shown) for pumping concrete for lining, and the tip of the pipe has an inspection window and a placement hole (see FIG. (Not shown).

Next, the installation location and fixing (laying) method of the pair of conductive wires 101a and 101b in the concrete height measuring apparatus 100 of the present embodiment will be described in detail with reference to FIGS.
In the present embodiment, the pair of conductive wires 101a and 101b are connected to the end of the lining space S in the tunnel axis direction, that is, the inner surface of the end frame 9 that closes the aforementioned facet side end (on the lining space S side). The upper and lower directions of the tunnel extend along the plane) and are supported by the wife formwork 9.

  Specifically, as shown in FIG. 4 which is an enlarged view of a portion C in FIG. 2, a pair of conductive wires 101a bundled integrally between the back portion of the U-shaped needle 101d and the wife formwork 9, With the 101b positioned, the U-shaped needle 101d is struck onto the wife form frame 9 by a tucker or the like. By performing this at a plurality of positions at appropriate intervals in the extending direction, the pair of conductive wires 101a and 101b are fixedly supported on the inner surface of the end form frame 9. Accordingly, the pair of conductive wires 101a and 101b are laid such that the distance between one conductive wire 101a and the other conductive wire 101b is substantially constant over the entire laying path. In other words, the pair of conductive wires 101a and 101b are extended in parallel to each other.

  In addition, one end side of each of the pair of conductive wires 101a and 101b connected to the main body 102 is drawn out of the lining space S through a through-hole penetrating the end form 9 in the tunnel axis direction, Then, as shown in FIG. 1, it is routed to the tunnel center side and connected to the main body 102 installed on the tunnel bottom surface 5. The through hole of the end form 9 is formed at the foot of the lining space S, for example, at a position 60 cm from the tunnel bottom 5. The formation position of this through hole (in other words, the insertion position of the pair of conductive wires 101a and 101b into the lining space S) is not limited to this and can be determined as appropriate. The through direction of the through hole is not limited to the tunnel axis direction, and may be the tunnel radial direction. In this case, the through hole is formed in the mold 4. Further, the other end side of the pair of conductive wires 101a and 101b is located in the tunnel crown Sc as described above. In addition, since measurement accuracy will fall if water etc. attach to the end form 9 and the lead-out wiring part 101e (refer FIG. 1) of the main-body part 102 among a pair of conductive wires 101a and 101b, it is good to protect, for example with a rubber hose etc. .

  Here, the laying path of the pair of conductive wires 101a and 101b extending in the vertical direction of the tunnel is set to be parallel to the inner circumferential surface 1 of the tunnel, for example, as shown in FIG. The path length from the insertion position of the pair of conductive wires 101a and 101b at each point of the pair of conductive wires 101a and 101b along the laying path is proportional to the capacitance as described later.

  Next, an example of a method for measuring the launch height using the pair of conductive wires 101a and 101b laid as described above will be briefly described.

When concrete is placed in the lining space S and the concrete is filled around the pair of conductive wires 101a and 101b, a capacitor using concrete as an electrolyte is formed between the pair of conductive wires 101a and 101b. The capacitance of the capacitor increases as the concrete launch height from the tunnel bottom 5 increases. Here, a predetermined voltage is applied between the pair of conductive wires 101a and 101b, the voltage between the pair of conductive wires 101a and 101b after a lapse of a certain time is measured, and the measured voltage, applied voltage, elapsed time, etc. It is known that the capacitance of a capacitor can be calculated. And this electrostatic capacitance becomes large in proportion to the length (namely, path | route length) of the part immersed in concrete among a pair of conducting wire 101a, 101b. Moreover, since the laying route of the pair of conductive wires 101a and 101b is determined in advance, the relationship between the route length at each point of the laying route and the height from the tunnel bottom 5 corresponding to the route length is known in advance. Yes. Therefore, the correspondence relationship between the capacitance, the path length, and the height from the tunnel bottom surface 5 corresponding to the path length can be set in the main body 102 by using a function, data, or the like. Therefore, if the electrostatic capacity can be calculated, the launch height of the concrete from the bottom surface 5 of the tunnel is measured based on the calculated electrostatic capacity and the correspondence relationship between the electrostatic capacity, the path length, and the height. Can do.
Note that the above measurement method is an example, and any method may be used as long as it measures the capacitance between a pair of conductive wires and measures the concrete launch height based on the measurement result.

  Next, the construction method of the lining concrete in this embodiment is demonstrated easily with reference to FIGS. 1-3 and FIG. In the following description, it is assumed that the preceding lining concrete has already been constructed. In addition, the construction method of the lining concrete demonstrated below is also description of one Embodiment of the construction method of the lining concrete which concerns on this invention.

  After the construction of the preceding lining concrete, the end form 9 that has closed the end of the preceding lining space S in the tunnel axis direction is removed, and a pair of conductive wires 101a and 101b supported by the end form 9 are attached. Remove. This step corresponds to the “step of removing a pair of conductive wires” in the method for constructing lining concrete according to the present invention.

  Next, the formwork 4 in which the preceding lining space S is formed is moved in the tunnel axis direction, and adjacent to one end surface in the tunnel axis direction of the preceding (existing) lining concrete 8 (see FIGS. 2 and 3). A subsequent lining space S is formed. This step corresponds to the “step of forming a subsequent lining space” in the method for constructing lining concrete according to the present invention.

  Next, the end portion (face side end portion) opposite to the preceding lining concrete side in the subsequent lining space S is closed by the end form 9 and the inner surface of the end form 9 is, for example, preceded by The pair of conductive wires 101a and 101b removed from the lining concrete is attached. This step corresponds to the “step of attaching a pair of conductive wires” in the method for constructing lining concrete according to the present invention.

In the lining space S, concrete is placed on the left and right tunnel side walls Sa, Sa and the arch-shaped portions Sb, Sb, for example, inspection windows (not shown) provided on the left and right mold frames 4, respectively. ) Pour concrete from left and right alternately, and pile up concrete layers alternately left and right. Specifically, for example, concrete is placed in the left lining space S (Sa, Sb), and the concrete is placed in the left lining space S (Sa, Sb) measured by the concrete height measuring device 100. The measurement result of the raised height (solid line in FIG. 5) is monitored, and when the concrete is cast up to a predetermined height, the concrete placement on the left side is stopped. Then, a rod-like vibrator is inserted into the placed concrete by an operator from an inspection window (not shown), and vibration is applied to compact the concrete. Then, during the compaction of the left side, start placing the concrete on the right side, monitor the measurement result (broken line in FIG. 5), stop the concrete placement on the right side when it is launched to a predetermined height Compact concrete. By repeating this left-right alternate placement, the concrete placement on the left and right tunnel side walls Sa, Sa and the arch-shaped portions Sb, Sb is completed.
Thereafter, a concrete placement pipe is connected to a placement hole (not shown) appropriately formed at a position corresponding to the tunnel crown portion Sc of the formwork 4 to pump the concrete, and the concrete placement to the tunnel crown portion Sc is performed. Done. Thus, the subsequent lining concrete is constructed by placing the concrete in the subsequent lining space S. These steps correspond to the “step of building the subsequent lining concrete” in the method of building the lining concrete according to the present invention.
And, for example, after constructing the subsequent lining concrete, the subsequent lining concrete is used as the existing (preceding) lining concrete, the above-mentioned “step of removing the pair of conductive wires”, “step of forming the subsequent lining space ”,“ A step of attaching a pair of conductive wires ”, and“ A step of constructing the subsequent lining concrete ”are repeated to sequentially construct the lining concrete in the traveling direction of the tunnel lining.

  According to the concrete height measuring apparatus 100 according to the present embodiment, a pair of conductive wires that extend in the vertical direction along the inner surface of the end form 9, are supported by the end form, and are electrically insulated from each other. Since it is the structure which measures the concrete launch height based on the electrostatic capacitance between 101a and 101b, concrete launch using the fact that the capacitance changes as the concrete launch height increases The height can be measured. Moreover, the sensor for measuring the concrete launch height can be continuously arranged on the inner surface of the end form frame and measured. For this reason, it is possible to measure to what height concrete has been launched at an arbitrary time. That is, it is possible to detect the launch height continuously.

  In addition, the sensor for measuring the concrete launch height simply extends a pair of conductive wires 101a and 101b that are electrically insulated from each other along the inner surface of the end form 9, so that the pressure sensor Compared with the prior art provided with a plurality, the cost of the sensor and the cost of wiring construction can be reduced. In this way, it is possible to provide a concrete height measuring apparatus capable of measuring the concrete launch height with a simple configuration.

  In addition, in the conventional technology in which a pressure sensor is arranged on the exposed surface (inner peripheral surface) side of the lining concrete, there is a risk that the surface finish of the inner peripheral surface will be lowered, and consequently the quality of the lining concrete may be reduced. In the concrete height measuring apparatus 100 in the form, the pair of conductive wires 101a and 101b are provided on the end frame 9, and the sensor (the pair of conductive wires 101a and 101b) is provided on the inner peripheral surface (finished surface) of the lining concrete. Since it is not exposed, the surface finish of the inner peripheral surface of the lining concrete can be improved.

  In addition, after the construction of the lining concrete, the pair of conductive wires 101a and 101b can be removed when the end form 9 is removed, and the pair of conductive wires 101a and 101b can be reused for the construction of the subsequent lining concrete or the like. Since it can be utilized, the cost of the sensor can be further reduced.

  In addition, since the pair of conductive wires 101a and 101b are configured to extend in parallel to each other, it is possible to easily construct a function or data of the correspondence relationship between the capacitance, the path length, and the height.

And according to the construction method of the lining concrete according to the present embodiment, the lining concrete can be constructed by using the measurement result of the concrete height measuring device 100. It is possible to continuously detect and monitor whether or not it has been launched, and to carry out precise construction management. As a result, high quality of the lining concrete can be realized.
In addition, since the preceding lining concrete is constructed, the process includes removing the end form 9 from the preceding lining concrete and removing the pair of conductive wires 101a and 101b supported by the end form. The pair of removed conductive wires can be reused by being attached to the inner surface of the end form frame that closes the end of the subsequent lining space.

FIG. 6 shows a schematic configuration of a concrete height measuring apparatus 100 according to the second embodiment of the present invention. FIG. 6 is also a cross-sectional view of the tunnel at the center in the tunnel axial direction of the lining space. 7 is a cross-sectional view taken along the line DD of FIG. In FIG. 7, the gantry vehicle 7 is omitted for simplification of the drawing. FIG. 8 is a plan view of the mold 4 as seen from the direction of arrow E shown in FIG.
In addition, the same code | symbol is attached | subjected to the element same as 1st Embodiment, description is abbreviate | omitted, and only a different part is demonstrated. The method for measuring the concrete height is the same as in the first embodiment, and a description thereof will be omitted. And about the construction method of lining concrete, there is no "process of removing a pair of electrical conductors" mentioned above, and 1st Embodiment except preparing a new pair of electrical conductors for subsequent lining concrete construction Since it is the same, description is abbreviate | omitted.

  The pair of conductive wires 101a and 101b in the present embodiment extend in the vertical direction along the tunnel inner peripheral surface 1 (specifically, the surface on the lining space S side of a waterproof sheet 3 to be described later). It is supported by the inner peripheral surface (waterproof sheet 3).

  Here, as shown in FIG. 9 which is an enlarged view of F part of FIG. 7, spray concrete 2 is sprayed and primary supported on the inner peripheral surface 1 of the tunnel as described above, and a waterproof sheet 3 is provided thereon. It is pasted inside. The waterproof sheet 3 is formed by integrally forming a waterproof sheet portion 3a and a nonwoven fabric portion 3b, and is internally attached so that the waterproof sheet portion 3a side is the lining space S side. Therefore, the pair of conductive wires 101 a and 101 b are extended along the surface of the waterproof sheet 3 on the lining space S side. For example, as shown in FIG. 9, the pair of conductive wires 101a and 101b is attached to the waterproof sheet 3 with a vinyl tape 101d 'or the like so as not to impair the waterproof property of the waterproof sheet 3.

  Next, the laying path of the pair of conductive wires 101a and 101b in the present embodiment will be specifically described.

The pair of conductive wires 101a and 101b of the present embodiment is formed at the foot of the lining space S from the tunnel crown Sc (for example, the tunnel bottom surface) 5 to 60 cm)) along the surface of the waterproof sheet 3 on the side of the lining space S, and then on the surface of the side of the waterproof sheet 3 in the tunnel axis direction as shown in FIG. Along the side, it is laid horizontally on the side of the wife formwork 9. One end side of the laterally drawn horizontal wiring portion 101f is drawn out of the lining space S through a through-hole penetrating the end form 9 in the tunnel axis direction, as in the first embodiment. Then, as shown in FIG. 8, it is routed to the tunnel center side and connected to the main body 102.
In addition, at the time of concrete placement, the concrete is also filled around the horizontal wiring portion 101f, and the capacitance changes. In consideration of the increase in capacitance due to the horizontal wiring portion 101f, a function or data of the correspondence relationship between the capacitance, the path length, and the height from the tunnel bottom surface 5 is created and set in the main body portion 102. Thus, it is configured so that the concrete launch height can be measured. Moreover, the penetration direction of the through hole is not limited to the tunnel axis direction, and may be the tunnel radial direction. In this case, the through hole is formed in the mold 4. Specifically, for example, in the center of the tunnel axial direction, a through hole is provided toward the center of the tunnel at a position corresponding to the foot of the above-described lining space S of the mold 4, and the pair of conductive wires 101 a and 101 b Pull out one end to the tunnel center side. Accordingly, the pair of conductive wires 101a and 101b can be laid without providing the horizontal wiring portion 101f.

  According to the concrete height measuring apparatus 100 of the present embodiment, it is possible to measure to what height concrete has been launched at an arbitrary time, as in the first embodiment. Moreover, compared with the prior art provided with two or more pressure sensors, the cost of a sensor and the cost of wiring construction can be suppressed. Since the pair of conductive wires 101a and 101b are not exposed on the inner peripheral surface (finished surface) of the lining concrete, the surface finish of the inner peripheral surface of the lining concrete can be improved.

  By the way, for example, as described above, when placing concrete alternately on the left and right tunnel side walls Sa, Sa and the arch-shaped portions Sb, Sb, the placement stop at one of the tunnel side-wall portions Sa and the arch-shaped portion Sb is stopped. If there is a long free time from one to the next placement, the concrete that was previously placed (lower concrete) and the concrete that was placed later (upper concrete) will not be integrated into a state called “cold joint” End up. Therefore, since a cold joint state is reached after an appropriate time interval for stacking concrete, management of the idle time (laying time interval) is also an important parameter in construction management.

In the first and second embodiments, the main body 102 has been described as simply measuring the launch height. However, the idle time of the placement may be configured to be monitored.
For example, the main body 102 can determine the time when the amount of increase in the launch height within 1 min becomes equal to or less than the threshold as the placement stop time, and monitor the idle time for placement from this stop time. Like that. And the main-body part 102 is comprised so that a warning signal may be output when the increase amount of the launch height is less than a threshold value within the time (for example, 60 minutes) appropriately determined beforehand as an upper limit of free time. . Thereby, a cold joint can be prevented.

  In the first and second embodiments described above, the concrete compaction is described as being performed by an operator inserting a rod-shaped vibrator directly into the concrete through the inspection window. A plurality of vibrators may be attached on the inner side in the circumferential direction and the tunnel axis direction, and may be compacted by the plurality of vibrators. In this case, it is good to comprise so that the operating position of a vibrator may be switched based on the measurement result of the concrete height measuring apparatus 100. As a result, the vibrator to be operated can be switched and operated according to the concrete launch height, the concrete compacting process can be precisely managed, and as a result, the quality of the lining concrete can be improved. It is possible to provide a method for constructing possible lining concrete.

  In the first and second embodiments, the pair of conductive wires 101a and 101b has been described as being provided on the left and right sides of the tunnel. However, the present invention is not limited to this and may be provided only on one side. Since the lining spaces Sa and Sb on one side and the lining spaces Sa and Sb on the other side are substantially the same, the time required for placing each layer is determined from the measurement result of the launch height on one side. For example, the concrete may be placed on each layer on the other side for the same time as the placing time.

  Moreover, the construction method of the lining concrete according to the present invention is not limited to the configuration described in the above embodiment, but simply the concrete height measuring device 100 of the first embodiment, the second embodiment, and the modifications thereof. The structure which constructs lining concrete by placing concrete in the lining space using the measurement result may be used. Accordingly, it is possible to continuously detect and monitor the height at which the concrete is launched at an arbitrary time, and to achieve a common effect of being able to perform precise construction management.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not restrict | limited to the said embodiment, A various deformation | transformation and change are possible based on the technical idea of this invention.

1 ... Tunnel inner peripheral surface 4 ... Formwork 9 ... Wife formwork 100 ... ... Concrete height measuring device 101a, 101b ... A pair of conductive wires 102 ...... Main body S ...

Claims (5)

A concrete height measuring device that measures the height of the concrete that is placed in the lining space between the inner peripheral surface of the tunnel and the formwork opposed to the inner periphery,
A pair of conductive wires that extend in the vertical direction along the inner surface of the end form frame that closes the end of the lining space in the tunnel axis direction, are supported by the end form frame, and are electrically insulated from each other; ,
A main body for measuring the height of the concrete based on the capacitance between the pair of conductive wires;
Concrete height measuring device equipped with. The concrete height measuring device according to claim 1 , wherein the pair of conductive wires extend in parallel to each other. It said body portion, when the amount of increase in the beating up height within a predetermined time is equal to or less than the threshold, outputs a warning signal, concrete height measuring device according to claim 1 or 2. Using the measurement result of the concrete height measuring device according to claim 1 , a lining concrete construction method for constructing lining concrete by placing concrete in the lining space,
The step of removing the pair of conductive wires supported by the wife mold frame together with the wife mold frame closing the end of the preceding lining space in the tunnel axis direction,
Moving the mold forming the preceding lining space in the tunnel axis direction to form the subsequent lining space adjacent to one end surface of the preceding lining concrete in the tunnel axis direction;
A step of closing the end opposite to the preceding lining concrete side in the subsequent lining space with the wife mold and attaching the pair of conductive wires to the inner surface of the wife mold;
Placing concrete in the subsequent lining space and constructing the subsequent lining concrete;
Containing concrete lining method. A lining concrete construction method for constructing lining concrete by placing concrete in the lining space using the measurement result of the concrete height measuring apparatus according to any one of claims 1 to 3 .