JP7466751B2 - Underwater lining structure and lining construction method - Google Patents

Description

The present invention relates to a lining structure and a method for constructing a lining body that is installed underwater.

Patent Document 1 discloses a method for constructing an underwater tunnel in which multiple through-type boxes are lined up on the water bottom and joined to adjacent through-type boxes, both ends of the box group formed by joining multiple through-type boxes are sealed off from outside water, and the internal water remaining inside the box group is drained to create an air-filled state inside the box group.

JP 2005-009235 A

The method disclosed in Patent Document 1 requires the connection of the housings to be performed underwater, which places various constraints on the work involved.

In response to this, one possible method for constructing an underwater tunnel is to build a lining on the bottom of the water, excavate below the lining to create a space, and then construct a tunnel within that space. With this method, the challenge is how to prevent water from entering the space below the lining from underwater.

The present invention aims to construct a lining body that creates a space on the bottom of the water that is isolated from underwater.

The present invention is a method for constructing a covering structure to be installed on the bottom of water, and includes the steps of: arranging a plurality of plate members supported by the ground so as to cover the bottom of the water; arranging sealing members across adjacent plate members so as to cover the joint gaps between the adjacent plate members arranged on the bottom of the water; and excavating the bottom of the water covered by the plate members.

The present invention also provides a method for constructing a covering body to be installed on the bottom of water, which includes the steps of: arranging a plate member supported on the ground so as to cover the bottom of the water, with its ends supported by supports; arranging a sealing member between the plate member and the supports so as to cover the joint gap between the plate member arranged on the bottom of the water and the supports; and excavating the bottom of the water covered by the plate member.

The present invention also provides a method for constructing a covering body to be installed on the bottom of an underwater body, which includes the steps of arranging a plurality of plate members supported by the ground so as to cover the bottom of the body of water, arranging sealing members across the adjacent plate members so as to cover the joint gaps between the adjacent plate members arranged on the bottom of the body of water, and draining the water contained in the bottom of the body of water covered by the plate members.

The present invention also provides a method for constructing a covering body to be installed on the bottom of water, which includes the steps of: arranging a plate member supported on the ground so as to cover the bottom of the water, with its ends supported by supports; arranging a sealing member between the plate member and the supports so as to cover the joint gap between the plate member and the supports placed on the bottom of the water; and draining the water contained in the bottom of the water covered by the plate member.

The present invention also provides a lining structure in which a space is formed below a lining body that is installed on the bottom of the water underwater. The space is formed by blocking the intrusion of water from underwater using the lining body. The lining body has a number of plate members that are placed on the bottom of the water and supported by the ground, and a sealing member that is installed across the adjacent plate members to cover the joint gaps between the adjacent plate members.

The present invention also provides a lining structure in which a space is formed below a lining body that is installed on the bottom of the water underwater. The space is formed by blocking the intrusion of water from underwater by the lining body. The lining body has a plate member that is installed on the bottom of the water and supported by the ground, a support part that supports the end of the plate member, and a sealing member that is installed across the plate member and the support part to cover the joint gap, which is the gap between the plate member and the support part.

According to the present invention, a space that is blocked from water infiltration from underwater is constructed at the bottom of the water.

FIG. 2 is a cross-sectional view of a covering body according to an embodiment of the present invention. FIG. 2 is a plan view of a covering body according to an embodiment of the present invention. 4A is a plan view of the plate member, and FIG. 4B is a side view of the plate member. 4 is a cross-sectional view taken along line IV-IV in FIG. 2. 3 is a cross-sectional view taken along line VV in FIG. 2. 3 is a cross-sectional view taken along line VI-VI in FIG. 2. 3 is a cross-sectional view taken along line VII-VII in FIG. 2. 3 is a cross-sectional view taken along line VIII-VIII in FIG. 2. 3 is a cross-sectional view taken along line IX-IX in FIG. 2. 4A is a top perspective view of a first sealing member, and FIG. 4B is a bottom perspective view of the first sealing member. 4A is a top perspective view of a second sealing member, and FIG. 4B is a bottom perspective view of the second sealing member. 4A is a top perspective view of a third sealing member, and FIG. 4B is a bottom perspective view of the third sealing member. 13A is a top perspective view of a fourth sealing member, and FIG. 13B is a bottom perspective view of the fourth sealing member. 1A is a top perspective view of a fifth sealing member, and FIG. 1B is a bottom perspective view of the fifth sealing member. FIG. 2 is a cross-sectional view for explaining a method for constructing a lining body according to the present invention, showing the step of providing a support wall. FIG. 2 is a cross-sectional view for explaining a method for constructing a lining body according to the present invention, showing the process of dredging the water bottom. FIG. 2 is a cross-sectional view for explaining a method for constructing a lining body according to the present invention, showing the process of installing piles on the bottom of the water. 1 is a cross-sectional view for explaining a method for constructing a covering body according to the present invention, showing a process for placing a plate member and a sealing member. A cross-sectional view showing a first modified example of a covering body according to an embodiment of the present invention. A cross-sectional view showing a second modified example of a covering body according to an embodiment of the present invention. A cross-sectional view showing a third modified example of a covering body according to an embodiment of the present invention.

Below, we will explain the covering body 100 and its construction method according to an embodiment of the present invention with reference to the drawings.

The lining body 100 according to this embodiment is installed on the bottom of a river, sea, lake, etc. to construct a tunnel underwater. In the following, a lining body 100 installed in a river R will be described as an example. In addition, in the following, unless otherwise specified, the top and bottom in the vertical direction will be referred to as "upper" and "lower", respectively. The up and down direction in Figure 1 corresponds to the vertical direction, and the left and right direction corresponds to the horizontal direction. In addition, in each figure, some symbols are omitted for common, continuous, and overlapping configurations.

As shown in FIG. 1, the lining body 100 is a flat plate-like structure extending in a substantially horizontal direction. Below the lining body 100, a lower space S is formed that is isolated from the water of the river R, and into which water is discharged and filled with gas.

An existing concrete revetment 101 is provided along the bank of the river R. A concrete support wall 102 is provided on the bottom of the river R to support the lining body 100. The outer edge of the lining body 100 is supported on the ground G by structures such as the existing revetment 101 and the support wall (underground wall) 102. In other words, in a plan view perpendicular to the vertical direction (Figure 2), the area surrounded by the existing revetment 101 and the support wall 102 is the area where the lining body 100 will be constructed (hereinafter referred to as the "construction area").

In this embodiment, the heights of the lining body 100 and the existing revetment 101 are different. The end of the lining body 100 is supported by a bracket 103 attached to the existing revetment 101, as shown in FIG. 1. If the heights of the support wall 102 and the lining body 100 are different, the bracket 103 may be provided on the support wall 102 to support the lining body 100. Also, if the heights of the lining body 100 and the existing revetment 101 are approximately the same, the lining body 100 may be directly supported by the existing revetment 101. Note that in this embodiment, the support wall (underground wall) 102 is used, but it is not limited to a wall body, and may be a pile (not shown) installed underground.

In the following, the existing revetment 101, the support wall 102, and the brackets 103 attached to the existing revetment 101 or the support wall 102 that support the ends of the outer edge of the lining body 100 are collectively referred to as the "support part". Note that the support part only needs to be configured so that the ends of the plate member 10 are supported on the ground G via the support part. In other words, the ends of the plate member 10 do not necessarily need to be supported on the ground G via the support wall (underground wall) 102 or piles, as long as they are supported via something that has a certain strength, and do not necessarily need to be supported on the ground G via the support wall (underground wall) 102 or piles.

The configuration of the covering body 100 is described in detail below.

As shown in Figures 1 and 2, the covering body 100 comprises a plurality of plate members 10 adjacent in a substantially horizontal direction, and sealing members 30 that seal the joint gaps C (see Figures 4 and 5) between adjacent plate members 10 and the joint gaps C (see Figures 6 to 9) between the plate members 10 and the support parts to block the infiltration of water from the river R. The sealing members 30 are pressed by water pressure against each of the adjacent plate members 10 placed on the bottom of the river R to seal the joint gaps C and block the infiltration of water from the river R. The sealing members 30 are also pressed by water pressure against each of the plate members 10 placed on the bottom of the river R and the support parts to seal the joint gaps C and block the infiltration of water from the river R.

As shown in Figures 2 and 3, the plate member 10 is a plate-like member formed in a substantially rectangular shape in a plan view (see Figure 3(a)), and is made of, for example, steel. The plate members 10 are provided along the horizontal direction, and are arranged so that their normal lines are substantially parallel to the vertical direction (see Figure 1). In other words, the multiple plate members 10 are each provided parallel to the horizontal direction and are provided on substantially the same plane. The plate members 10 are placed on piles 105 installed on the bottom of the river R, and are supported from below by the piles 105. The plate members 10 are simply placed on the support parts and the piles 105, and are not fixed to them.

In this embodiment, as shown in FIG. 2, the plate members 10 are arranged in two rows in the width direction of the river R (left-right direction in the figure), and a predetermined number (multiple) of plate members are arranged in the flow direction (up-down direction in FIG. 2) corresponding to the construction area. The plate members 10 arranged in the width direction of the river R are approximately aligned in the same position relative to the flow direction. In other words, the plate members 10 are arranged in a grid pattern. The plate members 10 are arranged with horizontal gaps (joint gaps C, see FIG. 4). More specifically, as shown in FIG. 4, the plate members 10 are arranged in a grid pattern so that they do not overlap in the vertical direction (do not overlap in a plan view) and their sides face each other, and a joint gap C is formed between the sides of adjacent plate members 10. The plate members 10 may be arranged in one row or three or more rows in the width direction of the river R. The arrangement of the plate members 10 is not limited to a grid pattern.

The end of the plate member 10, which forms the outer edge of the covering body 100, is placed on the support wall 102 or bracket 103, which is the support part. Specifically, the end of the plate member 10 on one side in the left-right direction (right side in FIG. 2) is placed on the bracket 103 attached to the existing revetment 101. The end of the plate member 10 on the other side in the left-right direction (left side in FIG. 2) is placed on the support wall 102. Also, although some parts are not shown, the upstream end and downstream end of the plate member 10 arranged on the upstream and downstream sides are placed on the support wall 102.

The plate member 10 and the support portion on which the plate member 10 is placed are not completely in contact with each other so as to prevent the infiltration of water from underwater, and a joint gap C (see Figures 6 to 8) through which water can infiltrate is formed between the plate member 10 and the support portion. Therefore, in this embodiment, the joint gap C between the plate members 10 and the joint gap C between the plate member 10 and the support portion are arranged to form a lattice shape in a plan view.

As shown in FIG. 3, a cutout 10a having a rectangular cross section is formed on the outer edge of the upper side of the plate member 10 along the entire circumference of the rectangular outer shape of the plate member 10 in a plan view. As a result, the outer edge of the plate member 10 is formed thinner than the center, and a stepped structure is formed on the outer edge. As a result, as shown in FIG. 4, a storage space in which a sealing member 30 is placed is formed between adjacent plate members 10 by the cutout 10a of the plate member 10. The storage space formed by the cutout 10a of the adjacent plate members 10 is formed above the joint gap C so as to communicate with the joint gap C between the plate members 10. The horizontal width of the storage space (the dimension in the left-right direction in FIG. 4) is formed larger than the size of the joint gap C.

As shown in FIG. 4, in order to determine whether water has been drained from the bottom of the water below the lining body 100 in the construction method of the lining body 100 described later, one or more plate members 10 are provided with a first pressure sensor 60 (first pressure measurement unit) capable of measuring the pressure in the water, i.e., the area connected to the water area, and a second pressure sensor 61 (second pressure measurement unit) capable of measuring the pressure in the water, i.e., the area in the water area that is in a dry state where water intrusion into the water area is blocked. The first pressure sensor 60 is attached to the plate member 10 so as to measure the pressure in the water of the river R. The second pressure sensor 61 is attached to the plate member 10 so as to measure the pressure on the lower space S side (space on the joint gap C side) of the plate member 10 that is blocked from the water of the river R by the sealing member 30 of the lining body 100. The measurement results of the first pressure sensor 60 and the second pressure sensor 61 are input to a controller not shown.

The sealing members 30 are arranged in a number of different shapes to seal the joint gaps C formed in a grid pattern between the plate members 10 and between the plate members 10 and the support parts. First, the basic configuration common to all sealing members 30 will be described with reference to Figures 4 and 5.

As shown in Figures 4 and 5, each sealing member 30 mainly has a main body portion 31 that is housed in the cutout 10a of the plate member 10 and functions as a pressure-receiving portion, and a seal portion 40 that seals the gap between the plate member 10 or the support portion or the gap between the main body portions 31. The sealing member 30 blocks the intrusion of water from the river R into the joint gap C.

The main body 31 is formed in a box shape with an opening on the top surface. Specifically, the main body 31 has a bottom surface 32 that is placed on the plate member 10 or a support, and a plurality of side surfaces 35 that extend vertically upward from the outer edge of the bottom surface 32. The main body 31 is made of steel, for example, and has higher rigidity than the seal portion 40. The main body portions 31 of adjacent sealing members 30 are connected to each other. Note that the main body 31 does not necessarily have to have an opening on the top surface. In other words, the main body 31 is not limited to being box-shaped.

In this embodiment, the main body 31 of the sealing member 30 provided across adjacent plate members 10 is accommodated in the accommodation space formed by the notch 10a of the adjacent plate members 10 and placed on the adjacent main body 31. The main body 31 of the sealing member 30 provided across the plate member 10 and the support portion is partially accommodated in the accommodation space formed by the notch 10a of the plate member 10 and placed on the plate member 10 and the support portion. In this manner, the main body 31 of each sealing member 30 is merely placed on the plate member and/or the support portion, but is not fixed thereto. Note that the main body 31 of each sealing member 30 may be configured to be fixed to the plate member and/or the support portion, respectively.

The main body 31 of one or more sealing members 30 is provided with a valved pipe 62 for pumping and discharging groundwater contained in the bottom of the water covered by the plate member 10.

The seal portion 40 is, for example, a rubber gasket formed from rubber, which is an elastic member, and is attached to the main body portion 31. The seal portion 40 has a first elastic portion 41 (elastic portion) provided between the main body portion 31 and the plate member 10 or the support portion, and a second elastic portion 42 (elastic portion) provided between the main body portion 31 to which the seal portion 40 is attached and the main body portion 31 adjacent to the main body portion 31. The first elastic portion 41 and the second elastic portion 42 are connected to each other, and the seal portion 40 is formed in an endless shape. The seal portion 40 has a lower rigidity and a larger elastic modulus (deformation coefficient) than the main body portion 31.

Thus, the sealing member 30 has a common structure of having a main body portion 31 and a seal portion 40 to block the intrusion of water into the joint gap C, but the shapes of the main body portion 31 and the seal portion 40 differ depending on the position where they are placed. The sealing member 30 reliably blocks the intrusion of water into the joint gap C by using a composite of a relatively rigid material (hard to deform) and a relatively rigid material (easy to deform).

The specific shape of each sealing member 30 will be described below. As shown in FIG. 2, the covering body 100 has a first sealing member 30a provided across two plate members 10, a second sealing member 30b provided across four plate members 10 at the intersection of the lattice shape formed by the joint gap C, a third sealing member 30c provided across the side portion and support portion of one plate member 10, a fourth sealing member 30d provided across two plate members 10 and the support portion at the intersection of the lattice shape, and a fifth sealing member 30e provided across the corner portion and support portion of one plate member 10. The following describes each configuration of the sealing member 30 with the suffixes a to e corresponding to the first to fifth sealing members 30a to 30e.

[First sealing member 30a]
2, the first sealing member 30a is provided between the rectangular sides of the two plate members 10. The first sealing member 30a seals a joint gap C that extends linearly between the two plate members 10.

As shown in FIG. 10, the main body 31a of the first sealing member 30a has a bottom surface 32a formed in a rectangular shape in a plan view, and a side surface 35a extending from the outer peripheral edge of the bottom surface 32a perpendicular to the bottom surface 32a. The main body 31a is provided across the two plate members 10 so as to cover the joint gap C between the two plate members 10, and is accommodated in the accommodation space formed by the cutout 10a. A gap is provided in the horizontal direction (left-right direction in the figure) between the main body 31 accommodated in the accommodation space and the cutout 10a (see FIG. 4).

The first elastic portion 41a is provided along the notch 10a between each notch 10a and the main body portion 31a of adjacent plate members 10. The first elastic portion 41a is provided over the entire longitudinal direction of the main body portion 31a. As a result, the gap between the main body portion 31a and the notches 10a of the two plate members 10 is blocked by the first elastic portion 41a (see FIG. 4). Therefore, the first elastic portion 41a blocks the intrusion of water from the river R into the joint gap C through the gap between the inner wall of the notch 10a of the plate member 10 and the main body portion 31a.

The second elastic portion 42a is provided on the side portion 35a provided at both ends of the main body portion 31a in the longitudinal direction, in other words, on the side portion 35a facing the other sealing member 30. The second elastic portion 42a is formed in a substantially U-shape having a pair of parallel portions, one end of which is connected to the corresponding first elastic portion 41a, and a connecting portion that connects the other ends of the pair of parallel portions. In this way, the second elastic portion 42a is provided on the side portion 35a so as to connect the first elastic portion 41a that contacts one plate member 10 and the first elastic portion 41a that contacts the other plate member 10. In this way, the seal portion 40a is formed endlessly and attached to the main body portion 31.

[Second sealing member 30b]
2, the second sealing members 30b are provided between the corners of the four plate members 10 at the intersections of the lattice-shaped joint gaps C. The second sealing members 30b close the joint gaps C formed in a cross shape between the four plate members 10.

The bottom surface portion 32b of the main body portion 31b of the second sealing member 30b is formed in a cross shape in a plan view. The main body portion 31b is provided across the four plate members 10 so as to cover the joint gaps C between the four plate members 10, and is accommodated in the accommodation portion between the cutouts 10a.

As shown in FIG. 11, the first elastic portion 41b is formed in an L-shape corresponding to the shape of the corner of the notch 10a of each plate member 10, and is provided between each of the notches 10a of the four plate members 10 and the main body portion 31b.

In the main body 31b of the second sealing member 30b, which is formed in a cross shape, the four side portions 35b face the other sealing members 30. Therefore, the second elastic portion 42b is provided on these four side portions 35b. A pair of first elastic portions 41b faces each of the four side portions 35b that face the other sealing members 30. The second elastic portion 42b is formed in a roughly U-shape, similar to the first sealing member 30a, with a pair of parallel portions whose one ends are connected to the corresponding first elastic portions 41b, and a connecting portion that connects the other ends of the pair of parallel portions.

[Third sealing member 30c]
2, the third sealing member 30c is provided across an edge portion and the support portion of one of the plate members 10. The third sealing member 30c closes a joint gap C that extends linearly between one of the plate members 10 and the support portion.

The bottom surface portion 32c of the main body portion 31c of the third sealing member 30c is formed in a rectangular shape in a plan view. As shown in FIG. 12, the bottom surface portion 32c of the main body portion 31c of the third sealing member 30c is configured in a stepped shape having a first bottom wall surface 33c and a second bottom wall surface 34c that are formed at different vertical heights. As shown in FIG. 6, the stepped shape of the bottom surface portion 32 of the main body portion 31 of the third sealing member 30c is formed to correspond to the step formed by the support portion (support wall 102) and the plate member 10 placed on the support portion.

The first bottom wall surface 33c, which is at a relatively high position, is placed on the notch 10a of the plate member 10, and the second bottom wall surface 34c, which is at a relatively low position, is placed on the support portion. A first elastic portion 41c is provided between the first bottom wall surface 33c and the notch 10a of the plate member 10, and between the second bottom wall surface 34c and the support portion. The first elastic portion 41c is provided in a straight line corresponding to the notch 10a of the main body portion 31c.

A second elastic portion 42 is provided on the side surface portion 35c at both ends of the main body portion 31 in the longitudinal direction. The configuration of the second elastic portion 42c is similar to the shape of the second elastic portion 42a of the first sealing member 30a, so a description thereof is omitted.

[Fourth sealing member 30d]
2, the fourth sealing member 30d is provided between the corners of the two plate members 10 and the support portion, at the intersections of the lattice-shaped joint gaps C. The fourth sealing member 30d closes the T-shaped joint gaps C formed between the two plate members 10 and the support portion.

The bottom surface 32d of the main body 31d of the fourth sealing member 30d is formed in a T-shape in a plan view. As shown in Figures 7, 8, and 13, similar to the third sealing member 30c, the bottom surface 32d of the main body 31d of the fourth sealing member 30d is configured in a stepped shape having a first bottom wall surface 33d and a second bottom wall surface 34d that are formed at different vertical heights.

As shown in Figs. 7 and 8, the first bottom wall surface 33d, which is at a relatively high position, is placed on the notches 10a of the two plate members 10, and the second bottom wall surface 34d, which is at a relatively low position, is placed on the support portion (support wall 102, bracket 103). A first elastic portion 41d is provided between the first bottom wall surface 33d and the notches 10a of the two plate members 10, and between the second bottom wall surface 34d and the support portion. The first elastic portion 41d between the notches 10a of the two plate members 10 and the main body portion 31d is provided in an L-shape corresponding to the corner of the notch 10a of the main body portion 31d. The first elastic portion 41d between the support portion and the main body portion 31d is provided in a straight line.

The main body 31d of the fourth sealing member 30d is formed in a T-shape, and three side surfaces 35d face the other sealing members 30. The three side surfaces 35d are provided with second elastic portions 42d. The configuration of the second elastic portions 42 is similar in shape to the second elastic portion 42 of the first sealing member 30a, so a description thereof will be omitted.

[Fifth sealing member 30e]
2, the fifth sealing member 30e is provided across a corner portion and a support portion of one of the plate members 10. The fifth sealing member 30e seals an L-shaped joint gap C formed between the corner portion and the support portion of one of the plate members 10.

The bottom surface 32e of the main body 31e of the fifth sealing member 30e is formed in an L-shape in a plan view. Similarly to the third sealing member 30c and the fourth sealing member 30d, the bottom surface 32e of the main body 31e of the fifth sealing member 30e is configured in a stepped shape with a first bottom wall surface 33e and a second bottom wall surface 34e that are formed at different vertical heights.

The first bottom wall surface 33e, which is at a relatively high position, is placed on the corner of the cutout 10a of the plate member 10, and the second bottom wall surface 34e, which is at a relatively low position, is placed on the support portion. A first elastic portion 41e is provided between the first bottom wall surface 33e and the cutout 10a of the plate member 10, and between the second bottom wall surface 34e and the support portion. The first elastic portion 41e of the fifth sealing member 30e is provided in an L-shape corresponding to the corner of the main body portion 31.

The body portion 31e of the fifth sealing member 30e is formed in an L-shape, and two side portions 35e face the other sealing members 30. Second elastic portions 42e are provided on these two side portions 35e. The configuration of the second elastic portions 42e is similar in shape to the second elastic portion 42 of the first sealing member 30a, so a description thereof will be omitted.

[Connection structure between adjacent sealing members 30]
Since the connection structure between adjacent sealing members 30 is the same regardless of the combination of sealing members 30, an example will be described in which the first sealing member 30a and the second sealing member 30b are connected, with reference to Figure 9.

A part of the side surface portion 35a of the main body portion 31a of the first sealing member 30a and a part of the side surface portion 35b of the main body portion 31b of the second sealing member 30b face each other. The facing side surface portion 35a of the first sealing member 30a and the side surface portion 35b of the second sealing member 30b are fastened by a bolt (not shown) inserted so as to avoid the second elastic portions 42a, 42b of each of them and fastened by a nut (not shown). As a result, the second elastic portion 42a provided on the side surface portion 35a of the first sealing member 30a and the second elastic portion 42b provided on the side surface portion 35b of the second sealing member 30b are sandwiched between the side surfaces 35a, 35b, respectively, and compressed by the fastening force of the bolt and nut. Therefore, the gap between the side surface portion 35a of the first sealing member 30a and the side surface portion 35b of the second sealing member 30b is sealed by the second elastic portions 42a, 42b of each of them.

As described above, by combining the first to fifth sealing members 30a to 30e and placing them in the cutout 10a of the plate member 10, the joint gaps C between the plate members 10 and between the plate member 10 and the support are entirely sealed, preventing the water of the river R from penetrating into the joint gaps C. As a result, a lower space S that is isolated from the water of the river R is formed below the covering body 100.

The first elastic portion 41 of the seal portion 40 of each sealing member 30 is provided between the main body portion 31 and the plate member 10 or the support portion in the vertical direction. The lower space S is formed as a space into which water is discharged and which is filled with gas. As a result, the first elastic portion 41 is pressed and compressed against the plate member 10 or the support portion by the weight of the main body portion 31 as well as the water pressure acting on the main body portion 31. This increases the adhesion between the first elastic portion 41 and the plate member 10 or the support portion, improving the sealing ability (water-stopping ability) of the first elastic portion 41.

In addition, in the covering body 100, a secondary waterstop rubber 50 is attached as a secondary sealing member to the opening of the joint gap C facing the lower space S. The secondary waterstop rubber 50 is a flexible waterstop joint, and is provided across the joint gap C between the plate members 10 and between the plate member 10 and the support. By attaching the secondary waterstop rubber 50, water intrusion into the lower space S is more reliably blocked. The secondary waterstop rubber 50 can be any shape, such as omega type, M type, or L type.

Next, we will explain how to construct the lining body 100 and how to construct the underwater tunnel.

First, we will explain how to construct the lining body 100.

In the method of constructing the lining body 100, as shown in FIG. 15, a support wall 102 is installed corresponding to the area in which the lining body 100 is to be constructed. The support wall 102 is formed, for example, by casting steel pipe sheet piles on the water bottom and casting coping concrete on the upper end of the steel pipe sheet piles. The support wall 102 also functions as a water barrier that blocks the inflow of groundwater at the bottom of the water into the lower space S formed by the lining body 100. The closed area surrounded in plan by the support wall 102 thus installed and the existing revetment 101 is the construction area in which the lining body 100 is to be constructed. In other words, the support wall 102 is installed on the water bottom so that the desired construction area is formed.

In addition, a water shielding wall 104 is installed in the ground on the side of the area of the bottom of the water covered by the lining body 100 and excavated as described below (in other words, the area that will later become the lower space S. Hereinafter referred to as the "excavation area"). More specifically, the water shielding wall 104 is installed in the ground on the opposite side of the support wall 102 across the existing revetment 101 that supports the plate member 10 so as to block the inflow of groundwater from the existing revetment 101 side into the excavation area (lower space S). The water shielding wall 104 and the support wall 102, which also functions as a water shielding wall, block the inflow of groundwater from the side into the excavation area and the lower space S formed by excavating the excavation area. This improves the workability of excavating the excavation area and constructing a tunnel in the lower space S described below. Note that the process of installing the water shielding wall 104 is not essential.

Next, the bottom of the water in the construction area is dredged to a depth corresponding to the thickness of the lining body 100. The dredged bottom surface is approximately aligned with the top surface of the support wall 102 (in other words, it is at the same height) as shown in FIG. 16. Note that this process is not limited to dredging the bottom surface, but may also involve smoothing out any unevenness in the bottom so that it fits the flat surface of the plate member 10. In other words, any method may be used for this process as long as it is possible to form an approximately flat installation surface on which the plate member 10 can be installed.

Next, as shown in FIG. 17, multiple piles 105 are installed on the bottom surface formed by dredging. The piles 105 are embedded in the bottom surface so as not to protrude from the bottom surface. In this embodiment, the height of the dredged bottom surface differs from the height of the existing revetment 101 supporting the lining body 100. For this reason, the bottom is dredged and brackets 103 are installed on the existing revetment 101 in the construction area. The brackets 103 are formed with a crank-shaped cross section and are installed along the existing revetment 101. The brackets 103 are formed with a support surface that is approximately the same height as the dredged bottom surface. The piles 105 may be driven (installed) prior to the formation of the installation surface, such as dredging and shaping the bottom.

Next, multiple plate members 10 are placed so as to cover the bottom of the construction area. The multiple plate members 10 are placed with horizontal gaps (joint gaps C). The multiple plate members 10 are also placed on the bottom of the water so that their ends are supported by the support walls 102 or brackets 103, which are the support parts.

Next, as shown in FIG. 18, sealing members 30 are placed in the cutouts 10a of the plate members 10 so as to seal the joint gaps C between the plate members 10 and between the plate members 10 and the support parts. Specifically, the sealing members 30 are formed in advance on land by attaching the seal parts 40 to the main body parts 31. The sealing members 30 are then thrown into water and housed in the cutouts 10a of the plate members 10, and the main body parts 31 of adjacent sealing members 30 are connected to each other with bolts and nuts. Note that the sealing members 30 may be individually thrown into water and placed on the plate members 10 and the support parts, or several sealing members 30 may be connected to each other in advance, and the connected sealing members 30 may be thrown into water and placed on the plate members 10 and the support parts.

In addition, when the plate members 10 are installed in the order of plate members 10-1, 10-2, etc., the sealing member 30 may be temporarily fixed to the plate member 10-2 adjacent to the previously placed plate member 10-1, and the plate member 10-2 may be placed adjacent to the previously placed plate member 10-1. Even in such a case, the sealing member 30 temporarily fixed to the plate member 10-2 will be placed between the plate members 10-1 and 10-2 (between the plate members 10). Similarly, between the plate member 10 and the support, the sealing member 30 may be temporarily fixed to the plate member 10 and placed, and then placed between the plate member 10 and the support.

Next, the bottom of the water in the construction area covered by the plate member 10 is excavated. When excavating the bottom of the water, first, the groundwater contained in the bottom of the water covered by the plate member 10 is drained. The groundwater can be drained, for example, by pumping water through a valved pipe 62 provided in the main body 31 of one or more sealing members 30. Note that the method of draining the groundwater is not limited to this method.

Whether the water on the bottom of the water covered by the plate member 10 has been drained is determined by comparing the measurement results of the first pressure sensor 60, which measures the pressure in the underwater space of the river R, and the second pressure sensor 61, which measures the pressure in the space on the joint gap C side separated from the river R by the first elastic part 41. If the difference in the measurement results of the first pressure sensor 60 and the second pressure sensor 61 is equal to or greater than a predetermined threshold, in other words, if the pressure difference between the underwater space and the space on the joint gap C side with the first elastic part 41 as a boundary is equal to or greater than a predetermined value, it is determined that the force pressing the sealing member 30 against the plate member 10, i.e., the notch 10a of the plate member 10, has acted sufficiently, and drainage is completed. Such confirmation of drainage may be performed automatically by a program executed by the controller, or may be performed by an operator checking the measurement results of the first pressure sensor 60 and the second pressure sensor 61 displayed on a monitor or the like.

When the water in the bottom of the water is drained, the bottom of the water is excavated to create the space necessary to form the tunnel. The bottom of the water is excavated, for example, by avoiding the support wall 102 and proceeding from below the existing revetment 101 in the width direction of the river R (to the left in the figure). Note that draining the groundwater before excavating the bottom of the water is not essential.

When the water contained in the bottom of the river is drained or the bottom of the river is excavated, water pressure is generated above the plate member 10 underwater in the river R, while no water pressure is generated below the plate member 10, which is atmospheric pressure. Therefore, the water pressure of the river R acts downward on the main body 31 of the sealing member 30 arranged in the cutout 10a of the plate member 10. When the water pressure acts on the main body 31, the first elastic part 41 of the sealing part 40 is pressed toward the plate member 10 or the support part and compressed. This seals the gap between the main body 31 of the sealing member 30 and the plate member 10 or the support part, and thus the joint gap C between the plate members 10 and the joint gap C between the plate member 10 and the support part. Therefore, the joint gap C is blocked from the water of the river R by the seal part 40 of the sealing member 30. The greater the difference between the measured values of the first pressure sensor 60 and the second pressure sensor 61, the greater the force of the water pressure pressing the sealing member 30 against the cutout 10a of the plate member 10. The greater the force with which the sealing member 30 is pressed against the notch 10a of the plate member 10, the more effectively the sealing member 30 can reduce the ingress of water into the lower space S.

Next, attach the secondary watertight rubber 50 to the entire joint gap C from the lower space S side.

In this manner, as shown in FIG. 1, a lining body 100 is constructed on the bottom of the river R, and a lower space S is formed below the lining body 100, preventing the infiltration of water from the river R.

In the lining body 100, the plate member 10 is only supported by being placed on the piles 105 and the support parts, and is not fixed to the piles 105 or the support parts. In addition, the seal part 40 of the sealing member 30 is not fixed to the main body part 31. Therefore, the lining body 100 has a flexible structure, and is easy to maintain the watertightness to the lower space S even if vibrations occur due to an earthquake or the like.

Once the lining body 100 is constructed, a tunnel is constructed in the space S below the lining body 100. The tunnel is constructed, for example, by connecting concrete boxes (so-called box culverts) that have a hollow portion and are formed in advance. Once the tunnel is constructed, the space below the lining body 100 is backfilled and the lining body 100 is removed. This results in the tunnel being constructed at the bottom of the river R.

The above embodiment provides the following effects:

In this embodiment, the sealing member 30 is pressed against the plate member 10 or the support by water pressure, thereby improving the watertightness of the joint gap C. This effectively blocks the space below the covering body 100 from underwater.

In addition, in this embodiment, the first pressure sensor 60 and the second pressure sensor 61 are used to check the drainage on the joint gap side before excavating the bottom of the water covered by the plate member 10. This can increase the safety of the excavation work.

The above describes the covering body 100 and its construction method according to this embodiment, but the following modified examples are also within the scope of the present invention. It is also possible to combine the configuration shown in the modified example with the configuration described in the above embodiment, or to combine the configurations described in the different modified examples below.

In the above embodiment, the first pressure sensor 60 and the second pressure sensor 61 are attached to the plate member 10. In contrast, the first pressure sensor 60 and the second pressure sensor 61 are not limited to being attached to the plate member 10. For example, as shown in FIG. 19, the first pressure sensor 60 and/or the second pressure sensor 61 may be attached to the main body portion 31 of the sealing member 30. Although not shown in the figure, the first pressure sensor 60 and/or the second pressure sensor 61 may be attached to a support portion.

In the above embodiment, the first pressure sensor 60 and the second pressure sensor 61 are provided to measure the pressure on the underwater side and the pressure on the lower space S side separated by the sealing member 30 (first sealing member 30a, second sealing member 30b) that seals the joint gap C between the adjacent plate members 10. Alternatively or in addition to this, as shown in FIG. 20, the first pressure sensor 60 and the second pressure sensor 61 may be provided so as to measure the pressure on the underwater side and the pressure on the lower space S side separated by the sealing member 30 (third sealing member 30c, fourth sealing member 30d, fifth sealing member 30e) that seals the joint gap C between the plate member 10 and the support part. In this case, the first pressure sensor 60 and the second pressure sensor 61 may be provided in the main body part 31 of the sealing member 30 that seals the joint gap C between the plate member 10 and the support part as shown in FIG. 20, or may be provided in the support part or the plate member 10. In this way, the position where the first pressure sensor 60 and the second pressure sensor 61 are provided can be any configuration.

In the above embodiment, the outer peripheral edge of the plate member 10 is formed with a rectangular cutout 10a, and the main body 31 of the sealing member 30 housed in the cutout 10a also has a rectangular cross section corresponding to the cutout 10a (see FIG. 4, etc.). In contrast, as shown in FIG. 21, the outer peripheral edge of the plate member 10 may have a tapered surface 10b formed in a shape that slopes toward the center of the plate member 10 as it moves vertically upward, instead of the cutout 10a. In this case, the main body 131 of the sealing member 30 has a trapezoidal cross section so as to correspond to the trapezoidal space formed by the tapered surface 10b of the adjacent plate member 10. In other words, the main body 131 having a trapezoidal cross section may be inserted into the trapezoidal cross-sectional space formed by the tapered surface 10b of the plate member 10 to form a wedge structure. Even in such a modified example, the same effect as in the above embodiment is achieved. The shape of the plate member 10 is not limited to the above embodiment or the modified example shown in FIG. 21. For example, the plate member 10 may simply have a flat plate shape with a rectangular cross section, without the notch 10a or tapered surface 10b. Also, the cross-sectional shape of the notch 10a is not limited to a rectangle as in the above embodiment.

Although the embodiments of the present invention have been described above, the above embodiments merely show some of the application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments.

This specification also includes the following forms:

The method for constructing a covering body to be installed on the bottom of the water includes the steps of: arranging a plurality of plate members so as to cover the bottom of the water; arranging sealing members that are pressed by water pressure against each of the adjacent plate members arranged on the bottom of the water to seal the gaps between the plate members and prevent water from entering; and excavating the bottom of the water covered by the plate members.

In the method for constructing the lining, the sealing member has a pressure-receiving portion that is provided across adjacent plate members and receives water pressure, and an elastic portion that is compressed between the pressure-receiving portion and the plate members by the water pressure acting on the pressure-receiving portion.

In the method for constructing a lining body, in the step of placing sealing members, multiple sealing members are placed along the joint gap, and the sealing members have a pressure-receiving portion that is provided across adjacent plate members and receives water pressure, a first elastic portion that is compressed between the pressure-receiving portion and the plate member by the water pressure acting on the pressure-receiving portion, and a second elastic portion that is provided between the pressure-receiving portion and the pressure-receiving portion of the sealing member adjacent to the pressure-receiving portion and blocks communication between the water and the joint gap through the gap between the pressure-receiving portions.

In the method for constructing a lining body, the process of excavating the water bottom is executed when the measurement results of a first pressure measuring unit that measures the pressure in the underwater space separated by the sealing member and a second pressure measuring unit that measures the pressure in the space on the joint gap side separated by the sealing member are equal to or greater than a predetermined threshold value.

The method for constructing the lining body further includes a step of installing a plurality of piles under the water bottom, and in the step of placing the plate member, the plate member is placed on the water bottom so that the plate member is supported by the piles.

The method for constructing a covering body to be installed on the bottom of the water includes the steps of: arranging plate members so as to cover the bottom of the water; arranging sealing members that are pressed by water pressure against the plate members and the supports that support the ends of the plate members to seal the gaps between the plate members and the supports and prevent water from entering; and excavating the bottom of the water that is covered by the plate members.

In the method for constructing the lining, the sealing member has a pressure-receiving portion that is disposed between the plate member and the support portion and receives water pressure, and an elastic portion that is compressed between the pressure-receiving portion and the plate member or the support portion by the water pressure acting on the pressure-receiving portion.

The covering body, which is installed on the bottom of the water, has multiple plate members placed on the bottom of the water, and sealing members that are pressed against each of the adjacent plate members by water pressure to seal the joint gaps between the plate members and prevent water from entering. The sealing members have a pressure-receiving portion that is installed across the adjacent plate members and receives water pressure, and an elastic portion that is compressed between the pressure-receiving portion and the plate members by the water pressure acting on the pressure-receiving portion, thereby sealing the gap between the pressure-receiving portion and the plate members.

The covering body, which is installed on the bottom of the water, has a plate member placed on the bottom of the water, a support part that supports the end of the plate member, and a sealing member that is pressed against the plate member and the support part by water pressure to seal the joint gap, which is the gap between the plate member and the support part, and prevent water from entering. The sealing member has a pressure-receiving part that is installed across the plate member and the support part and receives water pressure, and an elastic part that is compressed between the pressure-receiving part and the plate member and between the pressure-receiving part and the support part by the water pressure acting on the pressure-receiving part, thereby sealing the gap between the pressure-receiving part and the plate member and the gap between the pressure-receiving part and the support part.

100 Covering body 10 Plate member 30 Sealing member 31 Main body portion (pressure receiving portion)
40 Sealing portion 41 First elastic portion (elastic portion)
42 Second elastic portion (elastic portion)
60 First pressure sensor (first pressure measuring unit)
61 Second pressure sensor (second pressure measuring unit)
101 Existing revetment (support part)
102 Support wall (support part)
103 Bracket (support part)
105 Pile 131 Body C Joint gap

Claims (13)

A method for constructing a lining body installed on the bottom of a water body, comprising the steps of:
A step of disposing a plurality of plate members supported on the ground so as to cover the bottom of the water;
placing a sealing member across adjacent plate members disposed on the water bottom to cover seam gaps between the adjacent plate members;
and excavating the water bottom covered with the plate member.
Method of constructing the lining. A method for constructing a lining body installed on the bottom of a water body, comprising the steps of:
A step of placing a plate member supported on the ground so as to cover the bottom of the water, with its end supported by a support portion;
A step of disposing a sealing member across the plate member and the support portion so as to cover a joint gap between the plate member and the support portion disposed on the water bottom;
and excavating the water bottom covered with the plate member.
Method of constructing the lining. A method for constructing a lining body according to claim 1 or 2,
When the bottom of the water is excavated, water pressure acts to press the sealing members against each of the plate members.
Method of constructing the lining. A method for constructing a lining body installed on the bottom of a water body, comprising the steps of:
A step of disposing a plurality of plate members supported on the ground so as to cover the bottom of the water;
placing a sealing member across adjacent plate members disposed on the water bottom to cover seam gaps between the adjacent plate members;
and draining water contained in the bottom of the water covered by the plate member.
Method of constructing the lining. A method for constructing a lining body installed on the bottom of a water body, comprising the steps of:
A step of placing a plate member supported on the ground so as to cover the bottom of the water, with its end supported by a support portion;
A step of disposing a sealing member across the plate member and the support portion so as to cover a joint gap between the plate member and the support portion disposed on the water bottom;
and draining water contained in the bottom of the water covered by the plate member.
Method of constructing the lining. A method for constructing a lining body according to claim 4 or 5,
When the water contained in the bottom of the water vessel is drained, the sealing members are pressed against each of the plate members by the action of water pressure.
Method of constructing the lining. A method for constructing a lining body according to any one of claims 1 to 6,
The plate member is placed on a pile and supported on the ground.
Method of constructing the lining. A lining structure in which a space is formed below a lining body installed on the bottom of the water,
The space is formed by blocking intrusion of water from underwater by the lining body,
The covering body is
A plurality of plate members disposed on the bottom of the water and supported by the ground;
A sealing member is provided across the adjacent plate members so as to cover a joint gap between the adjacent plate members.
Covering structure. A lining structure in which a space is formed below a lining body installed on the bottom of the water,
The space is formed by blocking intrusion of water from underwater by the lining body,
The covering body is
A plate member disposed on the bottom of the water and supported by the ground;
A support portion that supports an end portion of the plate member;
A sealing member is provided across the plate member and the support portion so as to cover a joint gap between the plate member and the support portion.
Covering structure. The lining structure according to claim 8 or 9,
The plate member is placed on a pile and supported by the ground.
Covering structure. The lining structure according to claim 8,
The covering body includes four plate members arranged in a lattice shape,
At the intersections of the lattice shape between the corners of the four plate members, the joint gaps are formed in a cross shape in a plan view,
The sealing member is formed in a cross shape in a plan view and is provided across the four plate members so as to cover the joint gap formed in a cross shape.
Covering structure. The lining structure according to claim 9,
The covering body includes two plate members adjacent to each other and supported by the support portions,
A T-shaped joint gap is formed between the corners of the two plate members and the support portion in a plan view,
The sealing member is formed in a T-shape in a plan view and is provided across the two plate members and the support portion so as to cover the joint gap formed in a T-shape.
Covering structure. The lining structure according to claim 9,
the plate member has a corner portion supported by the support portion,
The joint gap is formed between the corner portion of the plate member and the support portion in an L-shape in a plan view,
The sealing member is formed in an L-shape in a plan view and is provided across the corner portion and the support portion of the plate member so as to cover the joint gap formed in an L-shape.
Covering structure.

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