Air lock chambers and air lock chamber systems

Abstract

To provide an airlock with fewer components requiring no grouting work.SOLUTION: A manlock 2 as an airlock is a manlock 2 that is placed on a workroom slab 12 in a pneumatic caisson 1. The manlock 2 is constituted of one or multiple box culverts 51-55 made of precast concrete; one or multiple plates 41-43 made of precast concrete; and multiple coupling mechanisms 60 that detachably connect one or multiple box culverts 51-55 and one or multiple plates 41-43.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an air lock chamber used in a pneumatic caisson construction method. [Background technology]

[0002] Generally, in the pneumatic caisson method, compressed air is pumped into a work chamber located at the bottom of the caisson, and excavation work is carried out while the air pressure expels groundwater. From the work chamber, a material shaft and man shaft extend above ground, with locks (air lock chambers) such as material locks and man locks installed along the way. Material locks and man locks are usually made of steel and installed at the top of the shaft, but they can also be placed at the bottom of the shaft, directly above the work chamber slab.

[0003] One such lock (air lock) is the bottom-locking manlock made of reinforced concrete. This bottom-locking manlock made of reinforced concrete can have a larger surface area than the top-locking manlock, allowing workers to decompress in a relaxed position with their legs stretched out, which is known to help prevent decompression sickness.

[0004] Furthermore, Patent Document 1 discloses an example in which a recovery lock is made of steel or prestressed concrete and has a semi-cylindrical shape with a semi-circular or horseshoe-shaped cross section that can be assembled and disassembled. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-150870 Summary of the Invention [Problem to be solved by the invention]

[0006] However, conventional manlocks made of cast-in-place reinforced concrete require breaking up the reinforced concrete when they are removed, which takes time to remove.Furthermore, the recovery lock in Patent Document 1 is attached to the workroom slab with anchor bolts, which can cause problems with the connection strength and airtightness.

[0007] In addition, when constructing a lock by placing precast blocks above a workroom, the applicants developed a lock structure that uses numerous prestressed steel rods to ensure airtightness and structural strength. However, the lock structure they developed used the workroom slab as the base when assembling the lock structure on top of it. This caused problems with the joints between the side walls (partition walls, gable walls) and the workroom slab. In other words, the workroom slab was constructed using cast-in-place concrete, which resulted in unevenness. To correct (adjust) this unevenness, grout injection work was required.

[0008] Therefore, an object of the present invention is to provide an air lock chamber that does not require grout injection work and has a small number of parts. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, the air lock chamber of the present invention is an air lock chamber installed on a work chamber slab in a pneumatic caisson, and is composed of one or more box culverts made of precast concrete, one or more plates made of precast concrete, and multiple connecting mechanisms that detachably connect the one or more box culverts and the one or more plates. [Effects of the Invention]

[0010] In this way, the air lock chamber of the present invention is an air lock chamber in a pneumatic caisson that is installed on top of a work chamber slab, and is composed of one or more box culverts made of precast concrete, one or more plates made of precast concrete, and multiple connecting mechanisms that detachably connect the one or more box culverts and the one or more plates. With this configuration, by constructing an air lock chamber made up of a box culvert and a plate on top of a work chamber slab, grout injection work is not required and the air lock chamber has a small number of parts. [Brief explanation of the drawings]

[0011] [Figure 1] This is a cross-sectional view of a pneumatic caisson cut along a vertical plane. [Figure 2] FIG. 1 is an explanatory diagram of an air lock system according to an embodiment. [Figure 3] Plan views of the air lock chamber, (a) is a bottom plan view, and (b) is an top plan view. [Figure 4] Cross-sectional view of the air lock chamber taken along line AA in Figure 3. (a) shows the case where the box culvert is divided, and (b) shows the case where the box culvert is integrated. [Figure 5] FIG. 10 is an explanatory diagram of a first modified example of an air lock system. [Figure 6] FIG. 10 is an explanatory diagram of a second modified example of an air lock system. [Figure 7] FIG. 10 is an explanatory diagram of a third modified example of an air lock system. [Figure 8] FIG. 10 is an explanatory diagram of a fourth modified example of an air lock system. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. [Example]

[0013] (Configuration of pneumatic caisson) First, the overall configuration of a pneumatic caisson 1 equipped with a manlock 2 as an air lock system of the present invention will be described using Figure 1. As shown in Figure 1, a cutting edge 11 with a tapered tip is formed at the bottom of a side wall 10 of the pneumatic caisson 1, and a work chamber 13 is formed by the inner surface of this cutting edge 11 and the underside of a work chamber slab 12. At least one excavator (not shown) is arranged inside the work chamber 13, and the ground is excavated by the remotely operated excavator to lower the pneumatic caisson 1.

[0014] A material shaft (not shown) extends from the workroom 13 toward the ground, with a material lock (not shown) installed at the top. An elevator shaft (man shaft) 14 also extends from the workroom 13 toward the ground, with man lock 2, an air lock chamber, installed at the bottom at a distance from the side wall 10. Furthermore, although not shown, compressed air equipment is installed to supply and exhaust compressed air into the workroom 13 and man lock 2.

[0015] In addition, although not shown, a central monitoring room has been installed on the ground near the pneumatic caisson 1. The central monitoring room monitors and manages the entire construction, including the delivery of materials via the excavator, material shaft, and material lock, and the removal of excavated earth and sand, the entry and exit of workers via the elevator shaft 14 and manlock 2, pressure management such as pressurization and depressurization within manlock 2, and display of the caisson's sinking amount, tilt, and other posture.

[0016] (Manlock configuration) Next, we will explain the configuration of the manlock 2 of this embodiment. The manlock 2 is composed of two rooms, a main room 31 and an auxiliary room 32, which are square (rectangular) in plan view as a whole, arranged side by side in the horizontal direction. Of these, an anchor ring for installing a work room hatch is embedded in the bottom slab of the main room 31, and an anchor ring for installing the elevator shaft 14 is embedded in the top slab of the auxiliary room 32.

[0017] 2 to 4, the manlock 2 of this embodiment is divided into a plurality of precast concrete box culverts 51 to 55 and a plurality of precast concrete plates 41 to 43 so that installation is simple and transportation, lifting and lowering with a crane are also easy. In other words, the manlock 2 as an air lock system of this embodiment is constructed by connecting the box culverts 51 to 55 and the plates 41 to 43 that become the gable walls and partition walls using a connecting mechanism 60.

[0018] The box culverts 51-55 are box-shaped (cubic) concrete structures, and because they are made of precast concrete, they have high dimensional accuracy. Furthermore, the box culverts 51-55 have a so-called precast reinforced concrete structure, with prestressing steel bars embedded in the top and bottom plates. Although not shown, waterproofing members are attached to the joint surfaces of the box culverts 51-55, allowing them to be pressed together to stop water leaks.

[0019] The two air lock chambers 31, 32 are separated by, from left to right, plate 41, which is the gable wall, the upper box culvert 53 and the lower box culvert 51, the upper box culvert 53 and the lower box culvert 52, the upper plate 43 and the lower plate 42, which are partition walls, the upper box culvert 54 and the lower box culvert 53, the upper box culvert 55 and the lower box culvert 53, and plate 41, which is the gable wall.

[0020] The box culverts 51-55 of this embodiment are configured by being divided into two members in cross section. Specifically, as shown in FIG. 4(a), they are divided into an upper box culvert 55 having a top plate and left and right side walls, and a lower box culvert 53 having a bottom plate and left and right side walls. These two box culverts 53, 55 are formed at the same height. A semicircular metal fitting for the elevator shaft 14 is embedded in the upper box culvert 55 (not shown). Furthermore, although not shown, it is preferable to provide a mating recess or mating protrusion for alignment on the joint surfaces between the box culverts 51-55. After the upper and lower box culverts 55, 53 are combined, they are connected vertically by a connecting mechanism 60. The configuration of the connecting mechanism 60 is substantially the same as the horizontal connecting mechanism 60 described later, and therefore, a description thereof will be omitted.

[0021] As mentioned above, the box culverts 53, 53 that make up the top slab of the main chamber 31, which do not have any embedded metal fittings or box cutouts, have the same structure as the box culverts 53, 53 that make up the bottom slab of the auxiliary chamber 32. By sharing parts in this way, it is possible to reuse formwork during manufacturing. Furthermore, the overall length can be changed by increasing the number of units that are connected.

[0022] Meanwhile, the multiple plates 41 to 43 include an undivided plate 41 that serves as a gable wall, and two divided plates 42, 43. Of the two plates 43, 42 that are divided into upper and lower halves, the lower plate 42 is equipped with a compressed air door to allow access between the main chamber 31 and the auxiliary chamber 32.

[0023] The number of divisions of the box culverts 51-55 and plates 41-43 described above is not limited to the specific examples. The number of divisions of these components is determined appropriately taking into consideration the size (span) of the manlock 2, size restrictions during transportation, and the lifting / lowering capacity of a crane. Depending on the size of the manlock 2, it is also possible to use a culvert box that is constructed as a single unit within the cross section without being divided, as shown in Figure 4(b). When dividing, it is preferable to change the division position appropriately so that the joint surfaces (joints) between adjacent box culverts are arranged alternately (staggered).

[0024] In this embodiment, a connecting mechanism 60 for detachably connecting these multiple parts is installed on the multiple box culverts 51 to 55 and plates 41 to 43. The number of connecting mechanisms 60 to be installed is not limited to the number shown in the figure, but is determined appropriately depending on the required compressive force, strength, etc.

[0025] The connecting mechanism 60 can use general PC steel members (PC steel rods or PC steel strands) and fixing devices (couplers as necessary) that connect box culverts. Specifically, multiple sheath holes can be provided in the box culverts 51 to 55, and the PC steel rods inserted into the sheath holes can be fixed using fixing devices while applying a tensile force using a jack. Note that the connecting mechanism 60 can also be connected using a method other than the use of PC steel members, for example, high-strength bolts.

[0026] (How to Build a Lock) Next, a method for constructing an air lock chamber will be described. The method for constructing an air lock chamber includes the following steps 1) to 9). 1) Install the box culverts (lower part) 51, 52 on the main room 31 side, align them with the anchor rings embedded in the workroom slab 12, and install the stoppers on the sides. 2) Install box culverts (upper part) 53, 53 on the main room 31 side. 3) The box culvert is connected vertically with PC steel rods. 4) Plates 42 and 43 are installed to serve as partition walls. 5) Install box culverts (lower part) 53, 53 on the side of the auxiliary chamber 32. 6) Install box culverts (upper part) 54 and 55 on the side of the auxiliary chamber 32. 7) The box culvert is connected vertically with PC steel rods. 8) Install plates 41, 41 that will serve as the gable walls. 9) The box culvert and the plate are connected horizontally with PC steel rods.

[0027] · Horizontal PC steel rods can be used for joining and tensioning each time, and can be connected with couplers, or multiple pieces can be joined at once. The order of installation and joining of the plates 41 that will become the gable wall can be prioritized in either order. - Box culverts are usually installed in a continuous manner, with the lower section first and then the upper section, but they may also be installed alternately, such as lower-upper-lower-upper. After installing the box culvert on the main room 31 side, a dog-shaped hatch will be installed in the anchor ring on the bottom slab. After installing the box culvert on the side of the auxiliary chamber 32, install the elevator shaft 14 on the anchor ring of the top plate.

[0028] (Method of dismantling and removing the air lock chamber) The method for removing the air lock is to follow the construction steps in reverse order. After dismantling, the box culverts 51 to 55 and plates 41 to 43 are cleaned of their joint surfaces and stored in a designated location.

[0029] (Pressure / Depressurization) Next, the procedure for pressurizing and depressurizing using the Manlock 2 of the embodiment will be described. (pressurized) 1) When pressurizing, enter the auxiliary chamber 32 from the elevator shaft 14, open the compressed air door and enter the main chamber 31. 2) Close the pressure doors of the bulkheads 42, 42 and pressurize the main chamber 31 to the same pressure as the working chamber 13. If necessary, pressurize by sucking in helium mixed gas. 3) Open the hatch and enter the workroom 13 to perform work. (decompression) 1) Open the hatch and move from the workroom 13 to the main room 31. 2) Depressurize the main chamber 31 according to the depressurization table. If necessary, inhale helium mixed gas or oxygen gas to depressurize. 3) After the pressure is reduced to atmospheric pressure, the compressed air door is opened and the person moves to the auxiliary chamber 32, and then moves to the ground level by elevator. In some cases, the person moves up and down by spiral staircase inside the shaft instead of the elevator.

[0030] (effect) Next, the effects achieved by the main chamber 31 and the sub-chamber 32 as the air lock chambers of this embodiment will be listed and explained. (1) As described above, the main chamber 31 and the auxiliary chamber 32 as air lock chambers in this embodiment are air lock chambers installed on the work chamber slab 12 in the pneumatic caisson 1, and are composed of one or more box culverts 51-55 made of precast concrete, one or more plates 41-43 made of precast concrete, and a plurality of connecting mechanisms 60, ... that detachably connect one or more box culverts 51-55 and one or more plates 41-43. With this configuration, by constructing the manlock 2 composed of the box culverts 51-55 and the plates 41-43 on the work chamber slab 12, grout injection work is not required, and the manlock 2 has a small number of parts.

[0031] In other words, in the case of the main chamber 31 and the auxiliary chamber 32 of the embodiment, the components can be joined with high precision because they are equipped with a factory-fabricated bottom slab separate from the work chamber slab 12. In other words, by incorporating the bottom slab as part of the box culverts 51 to 55, the grout injection work between the work chamber slab 12 as in the past is no longer necessary.

[0032] In addition, compared to when precast blocks are used, there is no need to embed a large number of steel rods in the work chamber slab 12, which reduces the structural impact on the work chamber slab 12. Furthermore, compared to when precast blocks are used, the overall rigidity is higher. Also, there are fewer joints between parts, which results in excellent airtightness and watertightness. Furthermore, if the box culvert is made of PRC, PC steel rods are embedded in the top and bottom slabs, and they can be stored without being removed from the product even after removal, eliminating the risk of damage or corrosion to the PC steel rods. Note that if the PC steel rods are placed protruding from the outer surface of the product, it is preferable to apply anti-rust treatment to the PC steel rods.

[0033] (2) Furthermore, it is preferable that one or more box culverts 51-55 are constructed as a single unit within the cross section, or that they are divided into multiple components within the cross section. If they are divided, the Manlock 2 can be constructed as an air lock chamber without being affected by transportation restrictions or the lifting / lowering capacity of the crane. Furthermore, by standardizing (matching) the height and width, the box culverts 51-55 can be unitized. For example, the same parts can be used in different locations. Furthermore, the overall length of the Manlock 2 can be changed by increasing or decreasing the number of box culverts 51-55 connected.

[0034] (3) Furthermore, one or more box culverts 51-55 and one or more plates 41-43 can be arranged adjacent to each other in the horizontal direction and connected horizontally by a connecting mechanism 60. This configuration allows for horizontal movement between the main chamber 31 and the auxiliary chamber 32, making movement easier. This makes it particularly easy to transport an injured person after decompressing them.

[0035] (4) Furthermore, one or more box culverts 51 to 55 and one or more plates 41 to 43 can be arranged adjacent to each other in the vertical direction and connected vertically by a connecting mechanism 60. With this configuration, the planar area occupied by the main chamber 31 and the auxiliary chamber 32 is reduced, so that manlocks 2 can be placed even in pneumatic caisson 1 with a small cross-sectional area.

[0036] (5) Furthermore, it is preferable that the connecting mechanism 60 has, for example, a tension rod and a fixing device installed on at least one end of the tension rod. With this configuration, the connecting mechanism 60 can fasten and fix the box culverts 51-55 and the plates 41-43 to each other, and prevent air leakage from the joint surfaces. Furthermore, the connecting mechanism 60 can be easily attached and detached.

[0037] (6) Furthermore, the manlock 2 as an air lock system of the embodiment can be composed of the above-mentioned multiple linked main chambers 31 and auxiliary chambers 32, a work chamber hatch connected to the bottom slab of the main chamber 31, which is the first air lock chamber of the multiple air lock chambers, and an elevator shaft 14 connected to the top slab of the auxiliary chamber 32, which is the second air lock chamber of the multiple air lock chambers. With this configuration, by connecting the elevator shaft 14 to the auxiliary chamber 32, the pressure can be reduced in the large space of the main chamber 31. [Example]

[0038] 5 to 8, Manlocks 2A to 2D will be described as air lock systems having different configurations from those of Example 1. Note that the same reference numerals will be used to describe parts that are the same as or equivalent to those described in Example 1.

[0039] As shown in Figure 5, Manlock 2A has a pressure capsule 90 connected to the gable wall of the main room 31, and an elevator shaft 14 connected to the gable wall of the auxiliary room 32. Furthermore, all box culverts 51 have the same shape (undivided) closed cross section. The plates 41 to 43 that form the gable walls also have the same shape. In this way, by connecting the pressure capsule 90, which includes the elevator shaft 14 and the workroom hatch 15, to the gable wall, it is possible to use box culverts 51 of the same shape. Furthermore, because no equipment is installed inside, the main room 31 and auxiliary room 32 can be made spacious.

[0040] Similarly, as shown in Figure 6, Manlock 2B has a pressure capsule 90 connected to the gable wall of the main room 31, and an elevator shaft 14 connected to the opposite gable wall of the same main room 31. Furthermore, all box culverts 51 have the same shape (undivided) closed cross section. The plates 41-42 that form the gable walls also have the same shape. In this way, by connecting the pressure capsule 90, which includes the elevator shaft 14 and the workroom hatch 15, to the gable wall, it is possible to use box culverts of the same shape. Furthermore, since no equipment is installed inside, the main room 31 can be made spacious.

[0041] As shown in Figure 7, the Manlock 2C has a workroom hatch 15 connected to the bottom slab of the main room 31, and an elevator shaft 14 connected to the top slab of the auxiliary room 32. Furthermore, all box culverts 51 have the same shape (undivided) closed cross section and are placed horizontally. The top slab, bulkheads, and plates 41 to 43 that form the bottom slab are also of the same shape. In this way, by connecting the elevator shaft 14 and workroom hatch 15 to the top slab and bottom slab, box culverts 51 of the same shape can be used in horizontal placement. Furthermore, because no equipment is installed inside, the main room 31 and auxiliary room 32 can be made spacious.

[0042] Similarly, as shown in Figure 8, the Manlock 2D has a work room hatch 15 connected to the bottom slab of the main room 31, and an elevator shaft 14 connected to the top slab of the same main room 31. Furthermore, all box culverts 51 have the same shape (undivided) closed cross section and are placed horizontally. The plates 41-42 that form the top and bottom slabs also have the same shape. In this way, by connecting the elevator shaft 14 and work room hatch 15 to the top and bottom slabs, box culverts 51 of the same shape can be used in horizontal placement. Furthermore, since no equipment is installed inside, the main room 31 can be made spacious.

[0043] The other configurations and effects are substantially the same as those of the first embodiment, and therefore the description thereof will be omitted.

[0044] Although the embodiments of the present invention have been described above in detail with reference to the drawings, the specific configurations are not limited to these embodiments, and design changes that do not deviate from the gist of the present invention are included in the present invention.

[0045] For example, in the embodiment, the directions in which the box culverts 51 to 55 and the plates 41 to 43 are arranged are described as "horizontal" and "vertical" for convenience, but these are not strict definitions and even a slight inclination is included in these concepts. In that sense, these can also be called "approximately horizontal" and "approximately vertical." [Explanation of symbols]

[0046] 1: Pneumatic caisson 10: Side wall 11:Blade mouth 12:Workroom slab 13:Workroom 14: Elevator shaft 15:Workroom hatch 2: Manlock (Air Lock System) 2A-2D: Manlock (Air Lock System) 31: Main room (Kilock room) 32: Antechamber (Ki-lock room) 41-43: Plate 51-55: Box culvert 60:Connection mechanism 90: Pressure capsule

Claims

1. In a pneumatic caisson, an air lock chamber is installed on the work chamber slab, one or more precast concrete box culverts; Several precast concrete plates and The system is provided with two manlock air lock chambers, each of which is composed of one or more of the box culverts and a plurality of connecting mechanisms that detachably connect the one or more of the box culverts and the plurality of plates; The two air lock chambers are arranged side by side horizontally via a partition wall, forming a first air lock chamber and a second air lock chamber, and a man shaft is connected to only one of the air lock chambers.

2. In a pneumatic caisson, an air lock chamber is installed on the work chamber slab, one or more precast concrete box culverts; Several precast concrete plates and The system is provided with two manlock air lock chambers, each of which is composed of one or more of the box culverts and a plurality of connecting mechanisms that detachably connect the one or more of the box culverts and the plurality of plates; The two air lock chambers are arranged side by side vertically via a partition wall, forming a first air lock chamber and a second air lock chamber, and a man shaft is connected to only one of the air lock chambers.

3. 3. An air lock chamber according to claim 1 or claim 2, wherein one or more of the box culverts are integrally formed within a cross section, or are divided into a plurality of members within a cross section.

4. 2. The air lock chamber according to claim 1, wherein one or more of the box culverts and a plurality of the plates are arranged adjacent to each other in the horizontal direction and are connected horizontally by the connecting mechanism.

5. 3. The air lock chamber according to claim 2, wherein one or more of the box culverts and a plurality of the plates are arranged adjacent to each other in the vertical direction and are connected in the vertical direction by the connecting mechanism.

6. 6. The air lock chamber according to claim 1, wherein the connecting mechanism comprises a tension rod and a fixing device installed on at least one end of the tension rod.

7. A plurality of linked air lock chambers according to any one of claims 1 to 6; a work chamber hatch connected to the bottom slab of a first air lock chamber among the plurality of air lock chambers; the man shaft connected to the top plate of a second air lock chamber among the plurality of air lock chambers; An air lock system consisting of:

8. A plurality of linked air lock chambers according to any one of claims 1 to 6; a work chamber hatch connected to a gable wall of a first air lock chamber among the plurality of air lock chambers; the man shaft connected to the end wall of a second air lock chamber among the plurality of air lock chambers; An air lock system consisting of:

9. One air lock chamber according to any one of claims 1 to 6; a work chamber hatch connected to the bottom slab or gable wall of the air lock; The man shaft connected to the top plate or gable wall of the air lock chamber; An air lock system consisting of:

Images