JP2002275908A - Compressed-air caisson execution facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently discharge excavated materials, sealing a pressured workroom. SOLUTION: In a compressed-air caisson execution facility in which a slab bottom plate 2 is installed onto the bottom section of a caisson 1, the workroom 4 formed to the lower section of the slab bottom plate 2 is supplied with compressed air and a ground is excavated by an excavator 6 mounted in the workroom 4, preventing the inflow of groundwater from an excavated ground facing the workroom 4, a ribbon screw 13 is arranged rotatably into a casing 12 and excavated materials are discharged continuously while a screw conveyor 11 for removing earth sealing the workroom 4 and the atmospheric air side 3 by soil and sand compressed in the casing 12 is penetrated on the slab bottom plate 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pneumatic caisson construction facility for use in the construction of foundations for bridges and structures, underground structures such as tanks, tunnels and shafts, and earth retaining structures such as quays and dry dogs. .

[0002]

2. Description of the Related Art By a pneumatic caisson method, a slab is provided at the bottom of a caisson body, compressed air is injected into a work space below the slab, and ground is excavated to a predetermined depth using an excavator while preventing inflow of groundwater. There is a so-called pneumatic caisson method.

In this pneumatic caisson method, an excavator installed in a work space is automated, such as by remote control, but an earth basket is used for discharging excavated earth and sand. This earth basket moves the basket loaded with earth and sand up and down, and discharges excavated earth and sand while preventing the pressurized air in the work space from being released by the material lock between the work space and the atmosphere side. It is.

[0004]

However, in the above-mentioned earth basket, the time required for adjusting the section formed in the elevating path of the basket to be equal to the atmospheric pressure or the working space, the time required for the movement of the basket, and the earth and sand There is a problem in that time is required for loading and unloading, opening and closing time of the material lock of the pressure control chamber, and the soil cannot be transported efficiently.

An object of the present invention is to solve the above-mentioned problems and to provide a pneumatic caisson installation facility capable of efficiently discharging excavated earth and sand while sealing a work chamber.

[0006]

According to the first aspect of the present invention, a slab bottom plate is installed in a caisson and pressurized air is supplied to a working chamber formed below the slab bottom plate. In a pneumatic caisson construction facility for excavating the ground by a drilling device installed in a work room while preventing inflow of groundwater from the excavated ground facing the work room, a spiral screw is rotatably disposed in a casing on the slab bottom plate. Then, the excavated earth and sand are continuously discharged, and a screw conveyor for earth discharging is provided to seal the working chamber and the atmosphere side with the earth and sand compressed in the casing.

[0007] According to the above configuration, the work chamber and the atmosphere side are sealed by the earth and sand conveyed by the earth discharging screw conveyor, and the excavated earth and sand is continuously discharged while maintaining the pressurized air pressure in the work chamber. As compared to conventional methods such as pressure adjustment and intermittent conveyance in the passage space of the earth basket, continuous discharge of earth and sand is possible and efficient, there is no unnecessary stop time, and compressed air leakage There is almost no power loss due to noise, sound leakage.

According to a second aspect of the present invention, there is provided the pneumatic caisson construction facility according to the first aspect, further comprising a charging / conveying device for supplying excavated earth and sand or a collecting device for collecting the excavated earth and sand at an entrance of the screw conveyor for earth discharging. It is provided.

According to the above configuration, the excavated earth and sand can be efficiently injected into the screw conveyor for earth discharging by the charging and conveying device. According to a third aspect of the present invention, in the pneumatic caisson construction facility according to the first aspect, a collecting device for scraping excavated earth and sand is provided at an entrance of the charging and conveying device.

According to the above configuration, the excavated earth and sand can be efficiently scraped and discharged by the collecting device. According to a fourth aspect of the present invention, in the pneumatic caisson construction facility according to any one of the first to third aspects, the helical screw of the screw conveyor for discharging soil is constituted by a ribbon screw.

[0011] According to the above-described structure, the ribbon screw does not have the co-rotation or adhesion of the earth and sand compared with the screw with the shaft, and the earth and sand can be efficiently conveyed and collected. According to a fifth aspect of the present invention, in the pneumatic caisson construction facility according to the fourth aspect, a fixed shaft that rotatably supports the ribbon screw or a ribbon shaft that rotatably supports the ribbon screw is provided in the hollow portion of the ribbon screw. A rotating shaft that rotates in the reverse direction is arranged.

According to the above construction, the fixed shaft can prevent the ribbon screw from being stretched due to the load of the earth and sand and the transport load, and the frictional force between the fixed shaft and the earth and sand can prevent the co-rotation of the earth and sand, which is effective. Transport and recovery becomes possible. Further, the rotating shaft further increases the frictional force with the earth and sand to prevent the earth and sand from co-rotating, thereby increasing the transport force by the ribbon screw. In addition, a collecting blade can be provided at the tip of the rotating shaft to improve the collection efficiency.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a pneumatic caisson construction facility according to the present invention will be described with reference to FIGS.

As shown in FIG. 1, a slab bottom plate 2 is installed at the bottom of a cylindrical or rectangular caisson main body 1 vertically installed in the ground, and an outer settling wall 1a having a pointed cross section is provided below the slab bottom plate 2a. A work chamber 4 surrounded by is formed. In the work room 4, a digging device 6 for driving a digging basket by a work arm is movably installed on a slab bottom plate 2 via a moving rail 5, and an operation room 7 partitioned from the work room 4 is provided.
The excavator 6 is remotely operated from. In the cab 7,
A manshaft 8 erected through the slab bottom plate 2 is connected, and is configured so that an operator can enter and exit the cab 7 from the atmosphere side 3.

As shown in FIGS. 2 and 3, the slab bottom plate 2 is provided with a screw screw conveyor 11 having a spiral screw, which is a helical screw, rotatably arranged around an axis in a cylindrical casing 12. Is vertically arranged via a setting tube 10 so as to be able to be inserted, removed, rotated, and slidably, and continuously discharges excavated earth and sand, and the work chamber 4 and the atmosphere side 3 are sealed by the earth and sand compressed in the casing 12. Thus, the pressurized air in the working chamber 4 is prevented from leaking to the atmosphere side 3.

The ribbon screw 13 of the screw conveyor 11 for discharging the earth is formed in a hollow shape in which nothing is provided in the hollow portion. A plurality of slewing rings 14 are mounted on the outer periphery of the ribbon screw 13 at predetermined intervals in the axial direction, and the slewing rings 14 are rotatably supported by the casing 12 via bearings. The swivel ring 14 prevents the ribbon screw 13 from being stretched due to the load of earth and sand and the transport load. The turning ring 14 is transmitted with a rotational driving force from a driving device 18 for discharging the earth. The driving device 18 for discharging the earth includes a passive ring gear 15 formed on the outer periphery of the turning ring 14 and an upper portion of the casing 12. , And a drive pinion 17 that is driven to rotate by the rotary drive device 16 via an interlocking shaft 16a and meshes with the passive ring gear 15. . Here, the passive ring gears 15 are provided on all the slewing rings 14, but the earth discharging drive device 18 may be connected to only some of the slewing rings 14. If the casing 12 is long, the rotary drive devices 16 may be arranged at a plurality of locations, and drive pinions 17 that mesh with the passive ring gears 15 may be provided.

The casing 12 includes a casing body 12.
a rotating casing 12b is rotatably supported around the axis via a bearing, and a loading screw feeder 21 is provided with a bearing screw 20 in a loading port 19 formed in a lower portion of the rotating casing 12b. Are connected so as to be able to swing up and down freely. The charging screw feeder 21 is configured such that a charging ribbon screw 23 is rotatably disposed around an axis in a charging casing 22, and the charging ribbon screw 2 is rotated by a charging rotation drive device 24 provided on the distal end side.
3 is driven to rotate. Thereby, the charging casing 2
The earth and sand fed into the loading hopper 25 attached to the front end side of the screw feeder 2 are fed to the screw conveyor 11 for discharging soil. In addition, a charging turning drive device 26 is provided below the casing main body 12a so as to turn the charging screw feeder 21 through the turning casing 12b to move the position of the charging hopper 25. Further, between the turning casing 12b and the charging casing 22,
A loading swinging device (a hydraulic or electric cylinder or jack, etc.) 27 that swings the loading screw feeder 21 up and down around the bearing device 20 is connected. The input turning drive device 26 includes a passive ring gear 26a attached to the turning casing 12b, and the passive ring gear 26a.
The driving pinion 26c is meshed with a and is driven to rotate by the turning driving device 26b.

As shown in FIG. 4, a discharge chute 29 is attached to a discharge port 28 formed on one side of the upper part of the screw conveyor 11 for discharging the earth, and the earth and sand discharge amount is adjusted to form a earth and sand plug. Opening and closing shutter device 3
The opening / closing shutter device 30 includes an opening / closing plate 30a for opening and closing the discharge port 28, and an opening / closing drive device (hydraulic cylinder device) 30b for sliding the opening / closing plate 30a in the vertical direction.

A discharge conveyor 41 is disposed below the discharge chute 29 and conveys the earth and sand discharged by the screw conveyor 11 for earth discharge to a sand discharge hopper 32. 33 is an air unit which is installed in the caisson body 1
4 is an air pipe for supplying pressurized air for preventing leakage of groundwater from the work chamber 4 to the work chamber 4.

FIG. 5 shows a second embodiment. In the following embodiments, the same member
The same reference numerals as those in the first embodiment denote the same parts, and a description thereof will be omitted. A discharging screw conveyor 41 is connected to the upper discharge port 28 of the discharging screw conveyor 11, and ribbon screws 13, 23, 42 of the discharging screw conveyor 11, the input screw feeder 21, and the discharging screw conveyor 41, respectively. The fixed shafts 43, 44, 45 are disposed at predetermined axial intervals at the hollow center axis positions of the hollow shafts. 13, 23, and 42 are configured to be supported, respectively.

This prevents the ribbon screws 13, 23, and 42 from elongating due to the weight of the soil and the transport load, and prevents co-rotation of the soil due to friction between the fixed shafts 43, 44, and 45 and the soil. Efficiency can be improved. The fixed shafts 43, 44, and 45 are connected to a rotation drive device as rotatable rotation shafts, and are rotated in the opposite direction to the ribbon screws 13, 23, and 42.
Further, the transport efficiency can be improved. Further, since the cross-sectional area of the casing 12 is reduced, the earth and sand plug is easily formed, and the sealing performance can be improved. Further, the air pipe 33 can be provided or formed using a fixed shaft 43 or a rotating shaft.

FIG. 6 shows a third embodiment. The discharge port 2 of the screw discharging conveyor 11 of the first embodiment is shown in FIG.
In the vicinity of 8, a plug adjusting device 50 capable of adjusting a forming zone 53 for forming a sediment plug is provided.

That is, a movable casing 51 is fitted to the upper end of the casing body 12a so as to be able to expand and contract, and the movable casing 51 has an outlet 28 having a discharge chute 29.
Is formed. Then, the ribbon screw 13 in the movable casing 51 is removed to provide a plug forming zone 53 in which a sediment plug is formed, and the movable casing 51 is moved in the axial direction by a plug adjusting drive device (hydraulic jack, cylinder, etc.) 52. The plug forming zone 53 is expanded and contracted by sliding
Can be adjusted, whereby the holding state of the pressurized air in the working chamber 4 can be adjusted.

FIGS. 7 and 8 show a fourth embodiment.
A collecting device 61 is provided at the lower end of the screw conveyor 11 for discharging soil to collect the excavated earth and sand. This collecting device 61 is provided with a rotary cylinder 62 for excavation rotatable around an axis via a bearing at a lower portion of the casing main body 12a.
The excavation rotary cylinder 62 is rotationally driven in the opposite direction to the ribbon screw 13 by the excavation collection drive device 63. The excavation collecting drive device 63 includes a passive ring gear 62a attached to an outer peripheral portion of the excavation rotary cylinder 62, a drive pinion 62b meshed with the passive ring gear 62a, and an excavation rotary drive for rotationally driving the drive pinion 62b. Device 62c
It is composed of At the lower end entrance 65 of the rotary cylinder 62 for excavation, a scraping blade 64 for excavating the ground and guiding earth and sand to the entrance is attached. In the hollow portion of the ribbon screw 13, a rotation shaft 67 that is rotated in the reverse direction with respect to the ribbon screw 13 by the rotation driving device 16 and supports the ribbon screw 13 at a predetermined position via a bearing is disposed. A scraping blade 64 is attached to the tip of the blade, and is supported via a bearing as necessary. A helical screw blade 66 for guiding excavated earth and sand to a lower end inlet 65 by rotation is attached to an outer peripheral portion of the excavating rotary cylinder 62.

In the above configuration, the excavation rotary drive unit 6
3, the ground is excavated in advance by rotating the scraping blades 64 so that the scraping blades 64 are buried in the excavated earth and sand. It can be guided to the screw conveyor 11 and discharged efficiently. In addition, the rotating shaft 43 disposed in the hollow portion of the ribbon screw 13 reduces the cross section of the casing 12 to promote the formation of the earth and sand plug to improve the sealing performance. , The earth and sand can be transported more efficiently. Instead of the driving members 62a to 62c of the excavating rotary cylinder 62, the rotary shaft 67 and the collecting device 61 may be connected, and the excavating rotary cylinder 62 may be rotated by the rotary shaft 67.

FIG. 9 shows that a reclaimer device (collection device) 71 having a plurality of excavation and collection baskets mounted on an outer peripheral portion of a rotating wheel driven by a driving device is provided at the tip of the input screw feeder 21. Things. With this reclaimer device 71, while excavating with a basket, the earth and sand excavated by the excavating device 6 can be raked and supplied to the input screw feeder 21, and efficient excavation can be expected. The screw conveyor 11
May be arranged so as to be able to move up and down via the installation tube 10 so that it can be moved up and down by a cylinder device (not shown).

According to each of the above embodiments, (1) The casing 1 is placed in the working chamber 4 filled with pressurized air.
Since the earth and sand are carried out by the ribbon screw 13 while the earth and sand are filled in the inside 2, leakage of the pressurized air in the working chamber 4 can be prevented at the same time by the earth and sand plug formed by the filled earth and sand in the casing 12. , It can discharge soil continuously. Screw conveyor 1
Since the case 1 is used, the earth and sand are filled in the casing 12, so that the power loss is small and the transportation efficiency is good.

(2) Since the earth and sand can be continuously discharged while sealing the work chamber 4 with the earth and sand plug, the entire apparatus can be downsized as compared with the conventional structure in which the earth basket is sealed with a material lock. can do.

(3) In comparison with the conventional method in which the earth basket is intermittently carried out with the material basket sealed with a material lock, the time required for discharge can be greatly reduced.

(4) Since the conventional material lock becomes unnecessary, the amount of leakage of the pressurized air can be greatly reduced, and the leakage noise is also eliminated, so that the power, the construction environment, and the operating cost are reduced. be able to.

(5) By disposing the fixed shaft 43 or the rotating shaft in the hollow portion of the ribbon screw 13, the formation of the earth and sand plug can be promoted and the sealing effect can be improved. Friction with the rotating shaft prevents the earth and sand from rotating together with the ribbon screw, thereby improving transportation efficiency.

[0032]

As described above, according to the first aspect of the present invention, the working chamber and the atmosphere side are sealed with the earth and sand to be conveyed and the pressurized air pressure in the working chamber is maintained by the screw discharging conveyor. Since the excavated soil can be continuously discharged while it is being drilled, it is possible to carry out the soil continuously and efficiently, as compared with the conventional pressure adjustment and intermittent conveyance in the passage space of the earth basket. There is no wasted downtime, and there is almost no power loss due to compressed air leaks, noise or air leaks.

Further, according to the second aspect of the present invention, the excavated earth and sand can be efficiently injected into the screw conveyor for discharging by the charging and conveying device. According to the third aspect of the present invention, the excavated earth and sand can be efficiently raked and discharged by the collection device.

[0034] According to the fourth aspect of the present invention, the ribbon screw does not have the co-rotation or adhesion of the soil as compared with the screw with the shaft, and the soil can be efficiently conveyed and collected. According to the fifth aspect of the present invention, the fixed shaft can prevent the ribbon screw from being stretched due to the load of the earth and sand and the transport load, and the frictional force between the fixed shaft and the earth and sand can prevent the co-rotation of the earth and sand, which is effective. Transport and recovery is possible. Further, the rotating shaft further increases the frictional force with the earth and sand to prevent the earth and sand from co-rotating, thereby increasing the transport force by the ribbon screw.

[Brief description of the drawings]

FIG. 1 is an overall vertical sectional view showing a first embodiment of a pneumatic caisson construction facility according to the present invention.

FIG. 2 is an enlarged vertical sectional view showing the screw conveyor for discharging soil.

FIG. 3 is a view taken in the direction of arrows AA shown in FIG. 2;

FIG. 4 is a view taken in the direction of arrows BB shown in FIG. 2;

FIG. 5 is an overall vertical sectional view showing a second embodiment of the pneumatic caisson construction facility according to the present invention.

FIG. 6 is a sectional view of an upper part of a screw conveyor for discharging soil, showing a third embodiment of the pneumatic caisson construction equipment according to the present invention.

FIG. 7 is an overall vertical sectional view showing a fourth embodiment of a pneumatic caisson construction facility according to the present invention.

FIG. 8 is an overall vertical sectional view of the screw conveyor for discharging soil.

FIG. 9 is an overall vertical sectional view showing a fifth embodiment of the pneumatic caisson installation facility according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Caisson main body 2 Slab bottom plate 3 Atmosphere side 4 Work room 5 Moving rail 6 Excavator 7 Operating room 11 Screw discharging conveyor 12 Casing 13 Ribbon screw 18 Discharge driving device 21 Input screw feeder 22 Input casing 23 Input Ribbon screw 24 Charging rotary drive 25 Charging hopper 26 Charging turning drive 27 Charging swinging device 30 Opening / closing shutter device 41 Discharging screw conveyor 42 Ribbon screw 43,44,45 Fixed shaft 50 Plug adjusting device 51 Movable casing 52 Plug adjustment driving device 53 Forming plug zone 61 Collection device 64 Scraping blade 71 Cramer device

Claims (5)

[Claims] 1. A slab bottom plate is installed in a caisson, and pressurized air is supplied to a work room formed under the slab bottom plate to prevent groundwater from flowing into the work room from the excavated ground facing the work room. In the pneumatic caisson construction equipment for excavating the ground by the installed excavator, a spiral screw is rotatably arranged in the casing in the slab bottom plate to continuously discharge the excavated earth and sand, and the earth and sand compressed in the casing. A pneumatic caisson construction facility characterized by a screw conveyor for discharging earth that seals between the working room and the atmosphere. 2. A pneumatic caisson installation facility according to claim 1, further comprising an input conveying device for supplying excavated earth and sand or a collecting device for collecting the excavated earth and sand at an entrance of the screw conveyor for earth discharging. 3. A pneumatic caisson construction facility according to claim 2, wherein a collecting device for raking excavated earth and sand is provided at an entrance of the charging and conveying device. 4. The pneumatic caisson construction equipment according to claim 1, wherein the spiral screw of the screw conveyor for discharging the earth is constituted by a ribbon screw. 5. A fixed shaft for rotatably supporting the ribbon screw, or a rotating shaft for rotatably supporting the ribbon screw and rotating in the reverse direction with respect to the ribbon screw, is disposed in the hollow portion of the ribbon screw. The pneumatic caisson construction equipment according to claim 4, wherein