Liner plate holding device and installation method
The liner plate holding device facilitates efficient and safe assembly of liner plates by suspending and stabilizing them for single-person connection, addressing labor intensity and safety issues in conventional methods.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- KANTO ELECTRIC KOJI
- Filing Date
- 2024-12-13
- Publication Date
- 2026-07-01
AI Technical Summary
Conventional liner plate assembly in shaft construction is labor-intensive, occupies limited workspace, and poses safety risks due to the need for multiple workers to lift and handle plates within a narrow shaft, mixing with excavation equipment.
A liner plate holding device with an upper and lower block structure that suspends and stabilizes liner plates, allowing for single-person assembly by engaging with flanges and enabling connection in mid-air, reducing the need for temporary placement on the shaft bottom.
Significantly reduces worker burden, enhances construction efficiency, optimizes workspace use, and improves safety by allowing stable handling and connection of liner plates without occupying shaft space.
Smart Images
Figure 0007883268000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a liner plate holding device and a construction method.
Background Art
[0002] There is known a liner plate shaft for constructing a cylindrical shaft wall in the ground by bolt - connecting steel liner plates subjected to corrugation processing to form an annular ring body and extending the ring body deeper as excavation progresses (Patent Documents 1 and 2). Liner plate shafts have many advantages such as high construction efficiency because construction is easy, can be excavated with small construction machinery, have little vibration and noise, and are less likely to affect the surrounding ground. Therefore, they are widely used in deep foundation construction methods such as the foundation of transmission towers, propulsion construction methods, and sump wells in landslide countermeasures. In the construction of a liner plate shaft, an excavator is placed inside the ring assembled with the liner plates to excavate the ground, the excavated soil is carried out of the shaft by a jib crane placed on the ground, and in parallel, the liner plates and backfill materials are carried into the shaft from outside the shaft. The liner plates are temporarily placed lying on the bottom surface of the shaft. In the connection work of the liner plates, two workers lift the liner plates temporarily placed in the shaft from both sides and press them against the lower flange of the lowermost liner plate constituting the shaft wall to hold them, and another worker inserts bolts through the bolt holes of the flange and screws on nuts to connect the liner plates to the shaft wall. The shaft construction method using liner plates is characterized in that the weight of one liner plate body is light and can be assembled by the manpower of 2 - 3 people, and the lifting weight can also be handled by existing machines such as a unique vehicle, a raft crane, and a jib crane. The assembly work of the liner plates at the bottom of the shaft is sometimes carried out manually because of their light weight. In light of the aging and declining workforce, numerous materials such as connecting materials have been developed to simplify the joining of liner plates in order to streamline assembly work (Patent Document 3). However, there are few inventions aimed at simplifying and streamlining the entire assembly process. In particular, for the work of attaching liner plates to the lower part of existing rings, there are devices such as lifting devices using winches (Patent Document 4) and hook-shaped members for simple lifting (Patent Document 5), but these have problems such as not being able to further reduce the manpower required for assembly work and having limited applications. [Prior art documents] [Patent Documents]
[0003] [Patent Document 1] Japanese Patent Application Publication No. 09-256774 [Patent Document 2] Japanese Patent Publication No. 2013-100695 [Patent Document 3] Japanese Patent Publication No. 2023-90798 [Patent Document 4] Japanese Utility Model Publication No. 03-100278 [Patent Document 5] Japanese Patent Publication No. 2021-75962 [Overview of the Initiative] [Problems that the invention aims to solve]
[0004] Conventional technology has the following problems: <1> The task of lifting 20-30 kg liner plates in a narrow liner plate shaft and holding them in the air with 2-3 workers places a heavy physical burden on the workers, and since 2-3 workers are required for connection, the construction efficiency is poor. <2> Temporarily placing the liner plates at the bottom of the shaft occupies limited space within the shaft, potentially hindering excavation work using backhoes and other equipment. <3> Because liner plates and backhoes are mixed together in the narrow liner plate shaft, there is a risk of contact during construction, and there is room for improvement in terms of safety.
[0005] The object of the present invention is to provide a liner plate holding device and a construction method using the liner plate holding device, in order to solve the problems of the prior art described above. [Means for solving the problem]
[0006] The liner plate holding device of the present invention comprises an upper block connectable to a suspension cable, a lower block installed below the upper block, and a hinge pivotally supporting the lower end of the upper block and the upper end of the lower block. The upper block comprises a support plate extending to the front side of the upper block and capable of supporting the upper flange of the liner plate from below, and a plurality of upper engaging pins projecting upward from the upper surface of the support plate. The lower block comprises engaging means capable of engaging with the lower flange of the liner plate, characterized in that the outer diameter of the upper engaging pins is smaller than the inner diameter of the bolt holes of the upper flange, and the spacing between the plurality of upper engaging pins corresponds to the spacing between the bolt holes of the upper flange.
[0007] The liner plate retaining device of the present invention may have an upper engaging pin that has a spherical head with a larger diameter than the neck portion.
[0008] The liner plate holding device of the present invention comprises an engagement means consisting of a pin guide installed below the lower block and a plurality of lower engagement pins projecting downward from within the pin guide, wherein the outer diameter of the lower engagement pins is smaller than the inner diameter of the bolt holes of the lower flange, the spacing between the plurality of lower engagement pins corresponds to the spacing between the bolt holes of the lower flange, and the lower engagement pins may be elastically biased downward from the pin guide.
[0009] The liner plate retaining device of the present invention may have a lower engaging pin with a tip surface that is inclined toward the rear side of the lower block with respect to the axis of the lower engaging pin.
[0010] The liner plate holding device of the present invention may have an upper block that includes a plurality of locking protrusions projecting upward from the side edge on the rear side of the support plate.
[0011] The present invention provides a construction method comprising: an upper attachment step of using a liner plate holding device to attach an upper block to the upper flange of an assembly liner plate and lift the assembly liner plate; a lower attachment step of attaching a lower block to the lower flange of an assembly liner plate while the assembly liner plate is lifted; a positioning step of moving the assembly liner plate below the lowest liner plate constituting the liner plate shaft and bringing the upper flange of the assembly liner plate into contact with the lower flange of the lowest liner plate; and a connecting step of connecting bolts through the bolt holes of the upper flange of the assembly liner plate and the bolt holes of the lower flange of the lowest liner plate and screwing nuts into them, wherein the positioning step and the connecting step are performed with the assembly liner plate lifted above the bottom surface of the liner plate shaft by a lifting device.
[0012] The construction method of the present invention may include a manual rope hoist from which the upper block is suspended from a suspension rope, and the positioning step may include a first positioning step in which the winch of the lifting device is used to position the assembly liner plate below the lowest liner plate that constitutes the liner plate shaft, and a second positioning step in which the rope hoist is used to bring the upper flange of the assembly liner plate into contact with the lower flange of the lowest liner plate. [Effects of the Invention]
[0013] The construction method of the present invention allows the liner plates to be bolted together while suspended, thus significantly reducing the physical burden on workers. Furthermore, since there is no need for workers to support the liner plates, and the work that previously required 2-3 people can be easily performed by one person, the construction efficiency is extremely high. Furthermore, by suspending the liner plates from outside the shaft into the shaft and connecting them directly to the shaft wall, there is no need to temporarily place the liner plates on the bottom of the shaft. This allows for more efficient use of the limited workspace within the shaft and improves safety during operations.
[0014] The liner plate has an arc shape, and its center of gravity is located inside the arc away from the center of the plate. Therefore, the balance in the lifted state is poor. Thus, if it is simply hung by locking a hook or the like at the center of the upper flange, the liner plate will tilt inward in the air, occupying a large area in the limited space in the pit, and it will easily sway and rotate around the locking part, making it difficult to handle. On the other hand, since the liner plate holding device of the present invention has a structure in which a foldable upper block and a lower block are locked and held on the upper and lower flanges of the liner plate, it is possible to reduce the inclination and rotation of the liner plate and handle it stably in a small working space. Moreover, since the lower block can be folded with respect to the upper block, it can be inserted in a folded state below the liner plate in the laid-down state. First, only the upper block is engaged with the upper flange and lifted, and after lifting, the lower block is engaged with the lower flange, so that it can be easily attached to the liner plate in a narrow shaft.
Brief Explanation of Drawings
[0015] [Figure 1] Explanation diagram of the liner plate holding device [Figure 2] Explanation diagram of the liner plate shaft [Figure 3] Explanation diagram of the liner plate [Figure 4] Explanation diagram of the upper attachment process [Figure 5] Explanation diagram of the lower attachment process [Figure 6] Explanation diagram of the connection process [Figure 7] Explanation diagram of Example 2
Modes for Carrying Out the Invention
[0016] Hereinafter, the liner plate holding device and construction method of the present invention will be described in detail with reference to the drawings. In this invention, terms such as "up," "down," "front," "back," "height direction," and "horizontal direction" refer to the directions in which the forward direction is defined as the direction viewed from the center of the liner plate shaft toward the outer periphery when the liner plate holding device is attached to the liner plate. Furthermore, in this invention, "suspending" includes all actions of suspending an object, lifting it up, and holding it suspended in the air. [Examples]
[0017] <1> Liner plate holding device (Figure 1) The liner plate holding device 1 of the present invention is a device that can be easily attached to a liner plate B and can stably hold the liner plate B, which has an unstable center of gravity, in a suspended state. The liner plate holding device 1 is used by suspending it from the suspension cable C1. The liner plate holding device 1 comprises at least an upper block 10 connected to a suspension cable C1, a lower block 20 installed below the upper block 10, and a hinge 30 that pivotally supports the lower end of the upper block 10 and the upper end of the lower block 20 in the width direction. The liner plate holding device 1 can be attached to the end of the suspension cable C1, for example, via a hook C2. Since the liner plate holding device 1 has a structure that holds the liner plate B from the inside, the liner plate B can be suspended even when a reinforcing ring is mounted on the upper flange B3.
[0018] <1.1> Liner plate shaft (Figure 2) Liner plate shaft A is a cylindrical hole excavated underground and can be used for various purposes such as shafts for deep foundation construction methods for steel tower foundations, shafts for pipe jacking methods, and water collection wells in landslide prevention work. Liner plate shaft A is constructed by assembling multiple liner plates B in a ring shape underground. Specifically, multiple liner plates B are bolted together in the circumferential direction to form a ring body, and the liner plate shaft A is constructed by bolting the ring body together vertically. In this case, it is desirable that the upper and lower liner plates B are connected with a predetermined angle offset in the circumferential direction. In the case of liner plate shaft A, if the earth pressure or groundwater pressure becomes high at depth, a reinforcing ring made of structural steel curved into an arc may be inserted between the upper and lower ring bodies.
[0019] <1.2> Liner plate (Figure 3) Liner plate B is an arc-shaped member that constitutes the liner plate shaft A. Liner plate B comprises a steel plate having a corrugated surface B1 formed by a corrugation process, two side flanges B2 attached to both sides of the steel plate, an upper flange B3 attached to the top edge, and a lower flange B4 attached to the bottom edge. Each flange is provided with bolt holes B5 that connect both sides, and by bringing the flanges of adjacent liner plates B into contact with each other, and passing bolts B6 through the bolt holes B5 and screwing nuts into them, multiple liner plates B can be connected vertically and horizontally. Furthermore, the liner plate holding device 1 of the present invention can be applied to any type or size of liner plate B, including, for example, a liner plate B for backfill injection in which a portion of the corrugated surface B1 is cut out.
[0020] <2> Upper block (Figure 1) The upper block 10 is a component that is fixed to the upper flange B3 of the liner plate B. The upper block 10 includes a support plate 11 capable of supporting the upper flange B3 of the liner plate B from below, and a plurality of upper engagement pins 12 projecting upward from the upper surface of the support plate 11. In this example, it further includes locking projections 13 provided on both sides of the support plate 11. In detail, for example, a square steel pipe with an engagement hole for a hook C2 at the top is used as the upper block 10, a support plate 11 is fixed to the upper front surface of the square steel pipe, and two upper engagement pins 12 are provided on the upper surface of the support plate 11. The upper engaging pin 12 has an outer diameter smaller than the inner diameter of the bolt hole B5 in the upper flange B3 of the liner plate B, and the distance between the two upper engaging pins 12 corresponds to the distance between the bolt holes B5 in the upper flange B3. In this example, the head of the upper engaging pin 12 is spherical and has a larger diameter than the neck portion of the head.
[0021] <2.1> Locking projection (Figure 1) The locking projection 13 is a projection for locking the upper flange B3 of the liner plate B onto the support plate 11. The locking projections 13 protrude upward from the side edges on the back side of the support plate 11, on both sides in the width direction of the upper surface of the support plate 11. However, the number of locking projections 13 is not limited to two, but may be three or more. The function of the locking projection 13 will be described later.
[0022] <3> Lower block (Figure 1) The lower block 20 is a component that is fixed to the lower flange B4 of the liner plate B. The lower block 20 is equipped with an engaging means 20' that can engage with the lower flange B4. In this example, the engagement means 20' comprises a pin guide 21 and a plurality of lower engagement pins 22 projecting downward from within the pin guide 21. In detail, for example, the lower block 20 employs a frame-like structure in which two parallel rectangular steel pipes are connected at the top and bottom by two plates. Two pin guides 21 extend from the bottom to the front of the frame-like structure, and through holes are provided on both sides of the pin guides 21, connecting them vertically, and the lower engaging pin 22 is held within the through holes. In this example, the lower engaging pin 22 is elastically biased downward from the pin guides 21 by a biasing means such as a spring. The lower engagement pin 22 has an outer diameter smaller than the inner diameter of the bolt hole B5 in the lower flange B3 of the liner plate B, and the distance between the two lower engagement pins 22 corresponds to the distance between the bolt holes B5 in the lower flange B4. In this example, the tip surface of the lower engagement pin 22 has a cross-sectional shape that is inclined in the direction of development of the lower block 20 with respect to the axis of the lower engagement pin 22 (Figure 5).
[0023] <4> Other configurations of the engaging means The engaging means 20' is not limited to a combination of the pin guide 21 and the lower engaging pin 22. For example, a hook-shaped pin that can rotate coaxially with the hinge 30 may be rotated and inserted into the bolt hole B5 of the lower flange B4 from above. Alternatively, a clamp-like structure may be used to support and grip the lower flange B4 from both sides. In short, the lower block 20 should be able to engage with the lower flange B4 of the liner plate B when it is extended downward relative to the upper block 10.
[0024] <5> Construction method The construction method of the present invention comprises at least an installation step S1, a positioning step S2, and a connecting step S3. In this example, we will describe the process of extending a new liner plate B (assembly liner plate B') below the liner plate B of the lowest ring body, in a state where multiple layers of annular ring bodies made of liner plates B have been constructed in a shaft excavated underground. One feature of the construction method of the present invention is that the positioning step S2 and the connecting step S3 are performed with the assembly liner plate B' suspended above the bottom surface of the liner plate shaft A. Each step is carried out as follows, for example:
[0025] <5.1> Installation Process Installation step S1 is the step of attaching the assembly liner plate B' to the liner plate holding device 1. Installation step S1 comprises an upper installation step S11 and a lower installation step S12.
[0026] <5.1.1> Upper mounting process (Figure 4) The upper mounting process S11 is the process of attaching the upper block 10 of the liner plate holding device 1 to the upper flange B3 of the assembly liner plate B'. In this example, the assembly liner plate B' is temporarily placed face down on the bottom surface of the liner plate shaft A with the corrugated surface B1 facing downwards. The liner plate holding device 1, with the lower block 20 folded, is inserted into the gap between the inner surface of the assembly liner plate B' and the bottom surface of the liner plate shaft A, with the hinge 30 side facing first. Insert the support plate 11 of the upper block 10 below the upper flange B3, and wind up the winch to press the side edge of the upper flange B3 against the upper surface of the support plate 11, gradually raising the assembly liner plate B'. Once the assembly liner plate B' begins to stand up, pass the two upper engagement pins 12 through the bolt holes B5 of the upper flange B3. The winch of the lifting device is wound up further, and the liner plate holding device 1 is lifted. As the winch hoists up, the assembly liner plate B', which was lying face down on the bottom surface of the liner plate shaft A, rises vertically, and the upper surface of the support plate 11 supports the lower surface of the upper flange B3 in a planar manner, lifting it into the air. In this example, the upper engagement pin 12 has a spherical head, making it easy to pass through the bolt hole B5, and its neck is thinner than the bolt hole B5. This prevents the upper engagement pin 12 from slipping out and coming loose when the orientation of the assembly liner plate B' is changed, as the bolt hole B5 can catch on it.
[0027] <5.1.1.1> Function of the locking projection When raising the inverted assembly liner plate B', the upper block 10 is pulled forward by the winch's winding mechanism, causing the side edge of the upper flange B3 to slide off to the back side of the support plate 11, requiring the support plate 11 and upper flange B3 to be reassembled. Therefore, in this example, a locking projection 13 is provided on the back side of the support plate 11. This prevents the side edge of the upper flange B3 from sliding down to the back side of the support plate 11 by contacting the locking projection 13, even when the winch is hoisted up and the side edge moves to the back side of the support plate 11.
[0028] <5.1.2> Lower mounting process (Figure 5) The lower mounting process S12 is the process of attaching the lower block 20 of the liner plate holding device 1 to the lower flange B4 of the assembly liner plate B'. With the assembly liner plate B' suspended inside the liner plate shaft A, the lower part of the lower block 20 is extended towards the assembly liner plate B', and the lower engagement pin 22 is passed through the bolt hole B5 of the lower flange B4. As a result, the liner plate holding device 1 holds the upper flange B3 and lower flange B4 from the inside, bringing the orientation of the lifted assembly liner plate B' closer to vertical, and making it easier to handle the assembly liner plate B' in the positioning process S2. In this example, since the tip surface of the lower engagement pin 22 is inclined in the direction of unfolding the lower block 20, by unfolding the lower block 20 and pressing the inclined tip surface of the lower engagement pin 22 against the side edge of the lower flange B4, the lower engagement pin 22 can be pushed upward and easily inserted into the bolt hole B5.
[0029] <5.2> Positioning Process Positioning step S2 is the process of positioning the assembly liner plate B' below the lowest liner plate B. The lifting device is operated to move the assembly liner plate B', which is suspended from the suspension cable C1, directly above the connection point of liner plate B. Next, the winch of the lifting device is operated to align the assembly liner plate B' suspended by the suspension cable C1 with the height of the lower liner plate B, which is the lowest liner plate in the liner plate shaft A, and the upper surface of the upper flange B3 of the assembly liner plate B' is brought into contact with the lower surface of the lower flange B4 of the lowest liner plate B.
[0030] <5.3> Consolidation Process (Figure 6) The connecting process S3 is the process of connecting the assembly liner plate B' to the bottom of the lowest liner plate B. Align the bolt holes B5 on the upper flange B3 of assembly liner plate B' with the bolt holes B5 on the lower flange of the bottom liner plate B. Next, insert bolt B6 through the upper and lower bolt holes B5 and screw on the nuts. If the upper and lower bolt holes B5 are slightly misaligned and it is difficult to insert bolt B6, you can insert the wrench end of a ratchet wrench into the upper and lower bolt holes B5 and wiggle it to fine-tune the position of the bolt holes B5 and make it easier to insert bolt B6. By performing these operations with the assembly liner plate B' suspended in mid-air, one person can easily connect the assembly liner plate B'. In particular, during the process of connecting liner plates B, when connecting the final assembly liner plate B' to form a ring, the assembly liner plate B' is first positioned on the ground side of the connection point, and then pulled towards the user to connect it. However, in the present invention, the operation of pulling towards the user can be performed with the assembly liner plate B' suspended in mid-air, making it possible to work more safely and efficiently compared to conventional techniques. [Examples]
[0031] [Example using a rope hoist (Figure 7)] In this example, a rope hoist C3 is used. The C3 rope hoist is composed of a combination of pulleys, plates, hooks, a ratchet mechanism, and ropes. It utilizes the principle of pulleys to amplify the lifting force, making it possible to lift heavy objects with minimal effort. The structure of the C3 rope hoist itself is publicly known and will not be described in detail here. In this example, a rope hoist C3 is suspended from the tip of the hook C2 of the lifting device, and in the positioning process S2, the assembly liner plate B' is lifted via the rope hoist C3. In detail, first, the winch is operated to position the assembly liner plate B' below the lowest liner plate B (first positioning step S21). Next, the rope of the rope hoist C3 is pulled in, and the assembly liner plate B' is raised little by little, so that the upper surface of the upper flange B3 of the assembly liner plate B' comes into contact with the lower surface of the lower flange B4 of the lowest liner plate B (second positioning step S22). In this example, fine adjustment of the height of the assembly liner plate B' becomes easier, improving the construction accuracy of the positioning process S2. Furthermore, it prevents overloading due to excessive winch winding and breakage of the suspension cable C1. [Explanation of Symbols]
[0032] 1. Liner plate holding device 10 Upper Block 11 Support plate 12 Upper engagement pin 13 Locking protrusion 20 Lower block 20' Engaging means 21 Pin Guide 22 Lower engaging pin 30 hinges A Liner Plate Shaft B Liner Plate B' Assembly Liner Plate B1 corrugated surface B2 side flange B3 Upper Flange B4 Lower Flange B5 Bolt Hole B6 bolt C1 Hanging rope C2 Hook C3 Rope Hoist S1 Installation process S11 Upper mounting process S12 Lower mounting process S2 Positioning process S21 First positioning process S22 Second positioning process S3 Connection Project
Claims
1. A liner plate holding device that holds a liner plate by being suspended from a suspension cable, It comprises an upper block connectable to the suspension cable, a lower block installed below the upper block, and a hinge pivotally supporting the lower end of the upper block and the upper end of the lower block in the width direction. The upper block comprises a support plate extending to the front side of the upper block and capable of supporting the upper flange of the liner plate from below, and a plurality of upper engaging pins projecting upward from the upper surface of the support plate. The lower block is equipped with an engagement means that can be engaged by inserting a plurality of lower engagement pins into the bolt holes of the lower flange from above the lower flange of the liner plate, The outer diameter of the upper engagement pin is smaller than the inner diameter of the bolt hole in the upper flange, and the spacing between the plurality of upper engagement pins corresponds to the spacing between the bolt holes in the upper flange. Liner plate holding device.
2. The aforementioned upper engaging pin is characterized by having a spherical head that is larger in diameter than the neck portion. The liner plate holding device according to claim 1.
3. The engagement means comprises a pin guide installed below the lower block and a plurality of lower engagement pins protruding downward from within the pin guide. The lower engaging pin is characterized in that its outer diameter is smaller than the inner diameter of the bolt hole in the lower flange, the spacing between the plurality of lower engaging pins corresponds to the spacing between the bolt holes in the lower flange, and the lower engaging pin is elastically biased downward from the pin guide. The liner plate holding device according to claim 1.
4. The lower engaging pin is characterized by having a tip surface that is inclined toward the rear side of the lower block with respect to the axis of the lower engaging pin. The liner plate holding device according to claim 3.
5. The upper block is characterized by having a plurality of locking protrusions that project upward from the side edge on the back side of the support plate. The liner plate holding device according to claim 1.
6. A construction method using a liner plate holding device according to any one of claims 1 to 5, in a liner plate shaft formed by assembling multiple liner plates in a ring shape, which is suspended from a suspension cable of a lifting device, The upper mounting process involves attaching the upper block to the upper flange of the assembly liner plate and lifting the assembly liner plate, A lower mounting step involves attaching the lower block to the lower flange of the assembly liner plate while the assembly liner plate is suspended, A positioning step involves moving the assembly liner plate below the lowest liner plate constituting the liner plate shaft, and bringing the upper flange of the assembly liner plate into contact with the lower flange of the lowest liner plate. The assembly includes a connecting step of connecting bolts to the bolt holes in the upper flange of the assembly liner plate and the bolt holes in the lower flange of the lowest liner plate, and screwing nuts into them. The positioning step and the coupling step are performed with the assembly liner plate lifted from the bottom surface of the liner plate shaft by the lifting device, Construction method.
7. Using a manual rope hoist that suspends the upper block from the aforementioned suspension rope, The positioning step is characterized by comprising: a first positioning step of using the winch of the lifting device to position the assembly liner plate below the lowest liner plate constituting the liner plate shaft; and a second positioning step of using the rope hoist to bring the upper flange of the assembly liner plate into contact with the lower flange of the lowest liner plate. The construction method according to claim 6.