JPH11117235A - Cantilever erection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To safely, expeditely and practically horizontally install a cantilever erection device use for a cantilever erection engineering method of a prestressed concrete girder. SOLUTION: Two main frames 1a, 1b installed in a protruding manner from the end of a cantilevered pier under construction towards the axial direction are respectively mounted with axial inclinometers 11a, 11b for detecting the axial inclination of the main frames 1a, 1b. A lateral connecting member 2a for connecting the main frames 1a, 1b together is mounted with a lateral inclinometer 12. A display device 13 for simultaneously displaying thus detected inclination is provided. A centralized operating device 14 for operating the actions of two main jacks 9a, 9b respectively supporting the main frames 1a, 1b at their ends and two anchor jacks 10a, 10b for adjusting the positions of the rear end of the main frames 1a, 1b is provided in parallel to the display device 13.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of supporting a prestressed concrete girder from a pier or abutment in a cantilever manner.
The present invention relates to a cantilever erection device used in a cantilever method (cantilever method) in which the tip is extended.

[0002]

2. Description of the Related Art Heretofore, a so-called cantilever method has been widely used as a method of constructing a prestressed concrete bridge having a large diameter. In this method, a new cantilever is installed at the tip of the bridge girder under construction. Thus, the work scaffold and the formwork are suspended and supported.

This cantilever erection apparatus includes at least two main frames installed so as to protrude from the tip of a bridge girder under construction, and a lateral connecting member such as a girder or a truss connecting the main frames laterally. A formwork for placing concrete and a work scaffold are suspended and supported by a suspending member locked to the main frame or the lateral connecting member. Each of the above main frames is supported by a main jack near the tip of the bridge girder, and the rear part of the main frame is locked to an anchor member fixed to the bridge girder, and the vertical position of the rear part is adjusted by the anchor jack. Is available. Therefore, by operating these main jacks and anchor jacks, the posture of each main frame and the relative position between the plurality of main frames are adjusted, and the cantilever erection device is installed substantially horizontally on the bridge girder.

[0004] As described above, the work of horizontally mounting the cantilever erection apparatus is performed by first operating the main jacks while checking the horizontality of the horizontal connecting members for connecting the main frames with the upper and lower parts of each main frame. Adjust the direction position. For example, the measurer installs a level on the lateral connecting member, measures the inclination in the lateral direction, reports the state of the inclination to the operator of the jack, and the operator of the jack operates one or more main jacks. Adjust so that the horizontal connecting member is horizontal. Next, the measurer sets the level on one main frame, measures the inclination in the axial direction, and the jack operator operates the anchor jack to adjust the inclination of the main frame. The adjustment of the inclination of the main frame is performed for each main frame. The work of the tilt measuring person and the jack operator causes the cantilever erection device to be installed substantially horizontally on the bridge girder.

[0005]

However, the above-mentioned cantilever erection apparatus has the following problems. In order to install the cantilever installation device almost horizontally as described above, the measurer checks the inclination with a level installed on each main frame or horizontal connecting member, and transmits the state to the jack operator. However, the operator of the jack must perform the operation of operating the jack based on the transmitted tilt state. For this reason, at least two persons, a measurer who checks the inclination and an operator of the jack, are required, and there is a problem that work efficiency is poor.

When the inclination of the horizontal connecting member is adjusted while measuring the inclination of the member, the inclination of the main frame in the axial direction is not generally measured.
The operator of the jack will recognize only visually. For this reason, even if the inclination of the main frame becomes too large, it may not be immediately recognizable, and such deformation may cause excessive stress at a joint portion of the members or a risk that the cantilever installation device may collapse. Will occur.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to make it possible to safely and quickly install the device almost horizontally with a simple operation, thereby greatly improving the working efficiency. The object of the present invention is to provide a cantilever erection device that can perform the above.

[0008]

In order to solve the above-mentioned problems, the invention according to claim 1 is provided so that the bridge girder is cantilevered and protrudes from the tip of the bridge girder being constructed in the axial direction of the bridge girder. And at least two main frames, and a lateral connecting member for connecting the main frames substantially at right angles to the axial direction, for driving new concrete at the tip of the bridge girder under construction to extend the bridge girder. A cantilever erection device that supports a work scaffold and a formwork, wherein each of the main frames is supported near the tip of the bridge girder, and the main frame is moved up and down to adjust a vertical position, and Acts on the rear end of the main frame, which is locked to the bridge girder or a member connected to the bridge girder and is prevented from jumping upwards. An anchor jacks for adjusting the position of downward, the axial tilt detector for detecting the respective axial inclination of the main frame, the lateral tilt detector for detecting a tilt of the transverse connecting member,
It has a display device for simultaneously displaying the inclination detected by the axial inclination detector and the lateral inclination detector, and a centralized operation device for operating respective operations of the main jack and the anchor jack.

According to a second aspect of the present invention, in the cantilever installation apparatus according to the first aspect, a tilt detected by the axial tilt detector and the lateral tilt detector instead of the centralized operation device. It is assumed that a control device for automatically controlling the operation of each of the main jack and the anchor jack based on the value is provided.

According to a third aspect of the present invention, in the cantilever erection device according to the first or second aspect, the axial tilt detector and the lateral tilt detector are arranged at distant positions. It has two liquid storage chambers, a connecting pipe that enables movement of liquid between these liquid storage chambers, and a liquid level sensor that detects a position of at least one liquid level in the liquid storage chamber. .

According to a fourth aspect of the present invention, in the cantilever erection apparatus according to the third aspect, the liquid contained in the liquid storage chamber is a liquid that does not freeze at a winter temperature in a cold region.

(Operation) In the cantilever erection device according to the first aspect, a main jack for supporting each of the main frames near the tip of the bridge girder is provided, and the main frame is provided with a lateral inclination detector displayed on the display device. Based on the detection result, each of the main jacks can be operated, and the main frame can be raised and lowered to adjust the horizontal connecting member to be substantially horizontal. Also, the rear end of each main frame is locked to a bridge girder or a member connected to the bridge girder, and is prevented from jumping up due to the weight of a shoring or a work scaffold supported in front of the main jack, The anchor jack acts on the rear end of the main frame to adjust the vertical position of the rear end of the main frame. Then, by operating the anchor jack based on the detection result of the axial direction tilt detector displayed on the display device, each main frame can be installed in a substantially horizontal direction. Therefore, it becomes possible for the operator of the jack to install the cantilever installation device substantially horizontally.

Further, in the above-mentioned cantilever installation apparatus, an axial inclination detector for detecting an inclination of each of the main frames in an axial direction, and a lateral inclination detection for detecting an inclination of a lateral connecting member connecting each of the main frames. The results detected with the display are simultaneously displayed on the display device. In addition, a centralized operation device for operating the main jack and the anchor jack is provided.The centralized operation device is operated based on information displayed on the display device, and the main jack or the anchor jack is simultaneously operated. Can also. For this reason, the jack can be operated while always monitoring the inclination of the main frame and the lateral connecting member, and it is also easy to operate a plurality of jacks simultaneously or sequentially so that the inclination is not excessive. it can. Therefore, it is possible to safely adjust the inclination of the cantilever installation device.

In the cantilever erection device according to the second aspect of the present invention, a control device for automatically controlling the operation of each of the main jack and the anchor jack is provided instead of the centralized operation device. Based on the inclination value detected by the inclination detector and the lateral inclination detector, the operation of each of the main jack and the anchor jack is automatically controlled, and the inclination of the lateral connecting member and the axial direction of each of the main frames are controlled. It is adjusted so that the inclination is almost horizontal. For this reason, the cantilever erection apparatus can be safely and quickly installed almost horizontally by a simple operation, and an operator who operates the jack and measures the inclination becomes unnecessary. This makes it possible to save labor and greatly improve work efficiency.

[0015] In the cantilever erection device according to the third aspect,
Each of the tilt detectors has two liquid storage chambers, which are in communication with each other, so that the liquid level of the liquid storage chamber fluctuates depending on the tilt of the attached member. Therefore, by detecting the position of the liquid surface, the inclination can be accurately detected with a simple structure. As the liquid stored in the liquid storage chamber, various liquids can be used as long as they have good fluidity such as water.

Further, in the cantilever erection device according to the fourth aspect, the liquid used in the tilt detector does not freeze even at the temperature in winter in a cold region, which may cause trouble in winter. The detection of the inclination can be performed without the need.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic side view showing a cantilever erection apparatus according to an embodiment of the present invention, and FIG. 2 is a schematic front view. FIG. 3 is a block diagram showing the configuration of this cantilever installation device.
FIG. 4 is a diagram showing a state where the bridge girder is mounted near the tip of a cantilevered bridge girder. The cantilever erection apparatus includes two rhombus-shaped main frames 1a and 1b which are installed so as to protrude from an end of a bridge girder in an axial direction of the bridge girder,
Girders (lateral connecting members) 2a and 2b for connecting the two main frames substantially at right angles to the axial direction are provided. Suspended members 3a, 3b are engaged with the girder 2a, 2b so as to be suspended, and the working scaffolds 4a, 4b are supported by the suspended members. A form receiving material 15 is provided above the work scaffold 4a, and thereby the form 5 is supported. One end of the form receiving member 15 is connected to and supported by the tip of the bridge girder 21, and the other end is suspended from the girder 2 b and supported.

The cantilever device 20 supports the main frames 1a and 1b in the vicinity of the tip of the bridge girder 21 and raises and lowers the main frames to adjust the vertical position of the main frames 9a and 9b. 9b,
Anchor jacks 10a and 10b are provided for raising and lowering the rear end of the main frame, which is prevented from jumping up by the anchor member 8, to adjust the position in the vertical direction. The main jack 9 and the anchor jack 10 are driven by hydraulic pressure, and are connected to the electric hydraulic pump 7 (drive device).

Further, each of the main frames 1a, 1b is provided with an axial tilt detector 11a, 11b for detecting an axial tilt, and a girder 2a above the main jack 9 is provided with a horizontal tilt detector. A lateral inclination detector 12 for detecting an inclination in the direction is provided. A display device 1 for simultaneously displaying the inclination values detected by the axial inclination detectors 11a and 11b and the lateral inclination detector 12
3 and a centralized operation device 14 that operates the electric hydraulic pumps that drive the main jacks 9a and 9b and the anchor jacks 10a and 10b are mounted side by side on one main frame 1a. The user can operate the centralized operation device 14 while watching the display device 13.

On the other hand, the rail 6 continuous in the axial direction is laid on the upper surface of the bridge girder 21.
It is possible to travel on the rail 6 and move forward by the wheels 16 attached to the lower front part. At this time, the main jack 9 is in a state in which the extendable portion is shortened, and is in a state in which the main jack 9 is not in contact with the upper surface of the bridge girder. Also, the rear ends of the main frames 1a and 1b
The rail 6 can be freely moved in the axial direction, and can be locked to the rail 6 so that even if the restraint of the anchor member 8 is released, the rail 6 is not jumped up by a forward load. I have. The rear portion of the rail 6 is connected to a bridge girder by an anchor steel member 17 so as to resist an upward lift acting from a rear end portion of the main frame 1.

Next, the operation of horizontally moving the cantilever erection apparatus 20 as described above to move the cantilever erection apparatus 20 forward and place concrete of the next block will be described. When moving the cantilever installation device 20 forward,
The wheel 16 is mounted on the rail 6 and the cantilever erection device 20
To the vicinity of the tip of the bridge girder 21. Then, the rear ends of the main frames 1 a and 1 b are connected to the bridge girder 21 by the anchor member 8. Next, by operating the centralized operation device 14, both the main jacks 9a, 9b are brought into contact with the upper surface of the bridge girder 21, and the main jacks 9a, 9b are turned on.
The main frame is supported by 9b, and one main jack 9a (reference jack) is pushed up or down to adjust the gap between the rail 6 and the wheel 16 to a predetermined interval. Accordingly, the main frames 1a, 1
b are tilt detectors 11a, 11b
And the inclination of the girder 2a is detected by the lateral inclination detector 12, and the respective inclination values are displayed on the display device 1.
3 is displayed. Then, based on the inclination value of the lateral inclination detector 12 displayed on the display device 13, the operation of the other main jack 9b is operated by the central operation device 14, and the girder 2 is adjusted to be substantially horizontal. At this time, the operation of the main jacks 9a and 9b is operated while confirming that the tilt values of the other detectors 11a and 11b are at a safe level. After the girder 2 is kept horizontal, the display 1
3, the anchor jacks 10a, 10b are determined based on the respective inclination values of the axial inclination detectors 11a, 11b.
The operation b is operated by the centralized operation device 14, respectively. Then, the main frames 1a and 1b are adjusted to be substantially horizontal in the axial direction.

In such a cantilever installation device 20, one operator can operate the centralized operation device 14 while looking at the display device 13, and can safely move the cantilever installation device 20 substantially horizontally by a simple operation. Can be installed.

After the cantilever erection device 20 is installed substantially horizontally as described above, the formwork 5 is fixed at a position adjacent to the block at the tip of the bridge girder where the concrete has been previously cast.
New concrete is poured into this. After the concrete of the new block has hardened, tension is introduced into the PC steel material continuously arranged between the concrete block and the previously installed block. As a result, the newly formed block is joined to the bridge girder being erected and integrated. Then, the cantilever installation device 20 moves forward to form the next block.

FIG. 5 is a schematic side view showing a cantilever erection apparatus according to an embodiment of the present invention, and FIG.
FIG. 2 is a block diagram showing a configuration of the cantilever installation device.
This cantilever erection device 50 replaces the centralized operation device 14 used in the cantilever erection device 20 shown in FIG. 1 with the inclination values detected by the axial inclination detectors 41 a and 41 b and the lateral inclination detector 42. The control device 44 controls the operation of the electric hydraulic pump based on the control device. That is, the operation of the electric hydraulic pump 37 is controlled based on the signal from the control device 44, and the main jack 39 and the anchor jack 40 are appropriately operated to automatically adjust the inclination of the main frame and the girder. Has become. The other configuration of the cantilever installation device 50 is the same as that of the cantilever installation device 20 shown in FIGS. 1 to 3.

The operation of the cantilever installation device 50 is as follows. First, the cantilever installation device is arranged at the tip of the bridge girder 21, and when a signal for starting the position adjustment operation is input to the control device 44, the electric hydraulic pump 47 operates based on the signal from the control device 44, Both main jacks 39 a and 39 b are in contact with the upper surface of the bridge girder 21. Then, the pushing amount of one main jack 39a is adjusted, and the main frame 31a is automatically stopped at a position where the main frame 31a has a predetermined height (for example, a position where a gap between the rail 36 and the wheel 46 is 30 mm).

Next, based on the inclination value detected by the lateral inclination detector 42, a signal for operating the other main jack 39b is output from the control device 44, and the main jack 39b is controlled so that the girder 32a is horizontal. The extrusion amount is adjusted. Then, when the girder 32a becomes substantially horizontal, the driving of the electric hydraulic pump 37 is automatically stopped. Thereafter, each of the axial tilt detectors 41
A signal for controlling the driving of each of the anchor jacks 40a and 40b is output from the control device 44 based on the inclination values detected by the a and 41b, the electric hydraulic pump 37 is operated, and the shafts of the respective main frames 31a and 31b are operated. The orientation of the direction is adjusted. Then, when it becomes substantially horizontal, the operation of the anchor jacks 40a, 40b is automatically stopped.

At this time, each detector 41a, 41b, 42
The operation of each jack 39a, 39b, 40a, 40b is controlled so that the inclination value detected by the main frame 31a,
It is possible to safely and quickly adjust the vertical position and posture of the base 31b.

After the operation of adjusting the position of the cantilever device is started, the position is automatically adjusted sequentially based on the signal output from the control device 44, and the inclination shown on the display device is adjusted. By simply monitoring the situation, the cantilever erection apparatus can be easily and quickly installed almost horizontally.

[0029]

As described above, in the cantilever erection apparatus according to the present invention, the postures of a plurality of main frames and the relative positions of these main frames can be efficiently adjusted, and the safety is improved by a simple operation. In addition, the cantilever erection device can be quickly and substantially horizontally installed. For this reason, it is not necessary to arrange a plurality of persons for the operation of the jack and the measurement of the inclination as in the case of the conventional cantilever installation apparatus, and the work efficiency can be greatly improved.

[Brief description of the drawings]

FIG. 1 is a schematic side view of a cantilever erection apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic front view of the cantilever installation device shown in FIG.

FIG. 3 is a block diagram showing a configuration of the cantilever installation device shown in FIG.

FIG. 4 is a schematic side view showing a state in which the cantilever erection apparatus shown in FIG. 1 is installed on a bridge girder being erected.

FIG. 5 is a schematic side view of a cantilever erection apparatus according to an embodiment of the present invention.

6 is a block diagram showing a configuration of the cantilever installation device shown in FIG.

[Explanation of symbols]

 1, 31 Main frame 2, 32 Girder 3, 33 Suspension material 4, 34 Work scaffold 5, 35 Formwork 6, 36 Rail 7, 37 Electric hydraulic pump 8, 38 Anchor member 9, 39 Main jack 10, 40 Anchor jack 11 , 41 Axial tilt detector 12, 42 Lateral tilt detector 13, 43 Display device 14 Central operation device 15, 45 Formwork receiving material 16, 46 Wheel 17 Anchor steel material 20, 50 Cantilever installation device 21 Bridge girder 44 Control device

Claims (4)

[Claims] 1. At least two main frames mounted in a cantilever manner so as to protrude in the axial direction of the bridge girder from the tip of the bridge girder under construction, and a lateral connection for connecting them at a right angle to the axial direction. And a cantilever erection device that supports a work scaffold and a formwork for extending new bridge girder by pouring new concrete at a tip of the bridge girder under construction, wherein each of the main frames is A main jack that supports near the tip of the bridge girder and adjusts the vertical position by raising and lowering the main frame, and is locked by the bridge girder or a member connected to the bridge girder, and is prevented from rising upward. An anchor jack acting on the rear end of the main frame to adjust the vertical position of the rear end of the main frame; and An axial tilt detector that detects the tilt of each axial direction, a horizontal tilt detector that detects the tilt of the lateral connecting member, and the axial tilt detector and the horizontal tilt detector that are detected. A cantilever installation device, comprising: a display device for simultaneously displaying the tilts; and a centralized operation device for operating respective operations of the main jack and the anchor jack. 2. The cantilever installation device according to claim 1, wherein, instead of the centralized operation device, based on a tilt value detected by the axial tilt detector and the lateral tilt detector.
A cantilever installation device having a control device for automatically controlling the operations of the main jack and the anchor jack. 3. The liquid crystal display device according to claim 1, wherein the axial tilt detector and the lateral tilt detector include: two liquid storage chambers disposed at a distance from each other; and a connecting pipe that enables movement of the liquid between these liquid storage chambers. The cantilever installation apparatus according to claim 1 or 2, further comprising a liquid level sensor for detecting a position of at least one liquid level in the liquid storage chamber. 4. The cantilever installation apparatus according to claim 3, wherein the liquid stored in the liquid storage chamber is a liquid that does not freeze at a winter temperature in a cold region.