JP3968380B1 - Removal method of expansion joint - Google Patents

Abstract

An expansion joint can be removed silently without using a breaker that is a source of noise.
A cutting groove 2 surrounding an expansion joint 1 is formed by a rotating blade alone. Inside the cutting groove 2, an auxiliary cutting groove 22 is formed in parallel with the expansion joint 1 and used for troubles. The corner of the cutting groove 2 is cut with a core drill, the cylindrical core is left, and the cutting groove at the corner is curved to make the wire saw 53 run smoothly. A pit 3 for accommodating the guide pulley is formed at a position along the cutting groove 2, the wire saw cutting machine 5 is fixed on the floor slab, the wire saw 53 is arranged in the cutting groove 2, and the wire saw is driven by the drive pulley 52. 53 is run, the floor slab and the expansion joint 1 are horizontally cut and removed.
[Selection] Figure 1

Description

  The present invention relates to a method for removing expansion joints such as elevated roads and bridges that need to be replaced due to aging and the like with low noise and low vibration without using a vibration generating device such as a breaker.

It is necessary to dismantle and remove expansion joints to repair or replace the expansion joints of bridges that have deteriorated due to long-term use or damaged.
To remove the expansion joint, the concrete floor slab integrated with the expansion joint must be cut and removed. Conventionally, circular blades are used for cutting concrete slabs.

Patent Document 1 (Japanese Patent Publication No. 7-26369) and Patent Document 2 disclose a method in which the expansion joint and floor slab to be removed are cut to an appropriate size and lifted with a jack to release the connection between the floor slab and the girder. (Japanese Patent Publication No. 7-26371).
Japanese Patent Publication No. 7-26369 Japanese Patent Publication No. 7-26371 JP 2001-226914 A

The expansion joint is firmly integrated with the concrete floor slab with anchors such as deformed reinforcing bars, and cannot be removed by cutting with a circular blade. It was scattered around. For this reason, there was a problem that the construction work time was limited. In particular, in the removal work of expansion joints on elevated roads in urban areas, there are buildings and residences close to the work site, so it is necessary to prevent the generation of noise as much as possible.
The present invention makes it possible to remove the expansion joint partly or completely without using a breaker which is a source of vibration and noise in removing the expansion joint and to remove it without using a peeling aid or a jack. It is to make.

A cutting groove that surrounds the expansion joint to be removed is formed, a corner portion of this cutting groove is cut with a core drill to form a curved portion, and a wire saw is installed in the cutting groove to horizontally cut the concrete slab or expansion joint. It is.
At that time, by leaving the core of the corner portion without removing it, the corner portion is curved to facilitate running at the initial cutting of the wire saw.
Further, by forming an auxiliary cutting line inside the cutting groove parallel to the formed expansion joint, it is possible to cope with troubles during the wire saw cutting operation.

  Further, a plurality of cutting lines are formed in parallel in the vicinity of the cutting groove and crushed to form pits serving as pulley installation spaces.

A cutting groove in which the wire of the diamond wire saw travels is formed around the expansion joint, and the expansion joint is removed by horizontal cutting at the bottom of the cutting groove. Both the formation of the cutting groove and the horizontal cutting by the wire saw are both low noise and low Since it is vibration and can be removed in a quiet state, it can be applied to expansion joints on urban highways where houses and buildings are close.
Since the corner portion of the cutting groove is cut with a core drill and the cylindrical core is left to form a curve, the wire saw can run smoothly and can be cut efficiently.
Since the auxiliary cutting line is formed inside the cutting groove parallel to the expansion joint, the floor slab concrete between the cutting groove and the auxiliary cutting line is removed using the auxiliary cutting line even if a trouble occurs with the wire saw. Accordingly, the wire saw can be released in a short time by lifting the expansion joint part with a jack, etc., and the interruption time of construction due to trouble can be shortened.
Furthermore, even in the formation of pits where pulleys that guide wire saws are installed, multiple cutting lines are provided with rotating blades, and thin concrete pieces are removed with wedges and bars to create pits, which generates noise and vibration during work. Is small and has little impact on the environment.

EXAMPLE A diamond wire saw cutting machine 5 used in the present invention comprises a base 50, a lifting guide 51, a drive pulley 52, and a wire saw 53 in which diamond beads are attached to a wire rope at regular intervals, as schematically shown in FIG. Is. The drive pulley 52 is attached to the elevating guide 51 so as to be movable up and down, is driven to rotate by a hydraulic motor, and the wire saw 53 wound around the drive pulley 52 is set so as to be wound around the cutting object via the guide pulley. The wire saw 53 travels at a high speed by the rotation of 52 and cuts the object.

As shown in FIGS. 1A to 1C, a cutting groove 2 having a width of about 15 mm is formed around the expansion joint 1 to be removed. Since a commercially available rotating blade alone cannot form a cutting groove having this width, a plurality of rotating blades (three in this embodiment) are stacked to form a cutting groove having a required width. Alternatively, a blade of a special size that can cut a width that can accommodate the wire saw can be used. For the depth of the cutting groove 2, a rotating blade having an appropriate diameter is selected according to the size of the expansion joint 1 to be removed. Further, since the cutting depth becomes shallower toward the cutting end due to the characteristics of the circular rotating blade, a surplus cut 25 beyond the intersecting portion of the cutting groove 2 is provided.
Two cutting grooves 2 are formed in the direction perpendicular to the bridge axis (parallel to the expansion joint) and the cutting grooves 21 are formed in the bridge axis direction to form a quadrangle. When the width of the cutting groove in the bridge axis direction is large, the cutting groove 21 for cutting the expansion joint 1 is formed so that the length of the wire saw 53 is not so long.
When one end of the expansion joint 1 is an open end as shown in FIG. 2, the open end serves as a substitute for the cutting groove 21, so that it is not necessary to form the cutting groove 21.

  An auxiliary cutting line 22 is formed inside the cutting groove 2 that accommodates the wire saw 53 in parallel to the expansion joint 1 (perpendicular to the bridge axis) and also in the bridge axis direction. The auxiliary cutting line 22 can be used by using the cutting groove 2 and the auxiliary cutting line 22 when a trouble occurs such that the wire saw 53 is caught by a reinforcing bar or an anchor installed in the floor slab and cannot run. The problem of biting the wire saw 53 is solved by crushing the concrete of the plate or widening the gap by using a jack. The width of the auxiliary cutting line 22 may be narrower than the cutting groove 2.

  The corner portion of the cutting groove 2 is cored by a core drill to form a circular cutting groove 23, the depth of the cutting groove at the corner portion is made constant over the entire length of the cutting groove 2, and the cylindrical core is located at the current position. The wire saw is allowed to run smoothly at the initial stage of cutting by making the corner of the cutting groove 2 curved.

A pit 3 that accommodates a guide pulley that changes the traveling direction of the wire saw is formed at a position along the cutting groove 2. In this embodiment, the pits 3 are provided at the corners of the cutting groove 2, but the pits 3 can be provided at appropriate positions such as the center of the cutting groove. Moreover, the pit 31 for installing the horizontal pulley which guides a wire saw is provided as needed. A modification of the arrangement of the pits 3 and the circular cutting grooves 23 is shown in FIG.
In order to form the pits 3, the following method can be used to easily form the pits 3 without generating noise.
A plurality of cutting lines 4 having the same depth as the cutting grooves 2 are formed in parallel at intervals of 2 to 4 cm between the widths of the pits 3 formed along the cutting grooves 2, and the pits 3 are perpendicular to the cutting lines 4. A cutting line 41 is formed at the end position. By inserting a wedge or a bar into the cutting line 4 and applying a force, the concrete subdivided into small pieces can be easily removed and the pit 3 can be formed.

The base 50 of the wire saw cutting machine 5 is fixed with a bolt on the floor slab in the vicinity of the pit 3, and the electric hydraulic unit and the hydraulic motor of the wire saw cutting machine 5 are connected by a hydraulic hose. The wire saw 53 wound around the drive pulley 52 is caused to make a round inside the cutting groove 2 via a guide pulley (not shown) provided at an appropriate position.
The drive pulley is raised along the lifting guide 51 to tension the wire saw 53. When the drive pulley 52 is rotated to circulate inside the cutting groove 2 and the drive pulley 52 is raised, the wire saw 53 bites into the floor slab concrete and horizontal cutting is started.

During the cutting operation by the wire saw 53, water is injected to cool the wire saw 53.
In the final phase immediately before the cutting is completed after the horizontal cutting has progressed, the wire saw 53 is likely to have an acute angle and is likely to break. Therefore, a horizontal pulley is arranged in the pit 31 provided on the opposite side of the pit 3 to By preventing 53 from becoming an acute angle, breakage can be prevented.
When the horizontal cutting is completed, the expansion joint 1 is lifted and removed together with the surrounding floor slab concrete.

  As explained above, unlike the conventional chipping work with a breaker, the generated noise is the rotation sound of the hydraulic motor and the traveling sound of the wire saw, and the work is performed in a much quieter state than the conventional method. Therefore, it is ideal for the removal work of expansion joints on bridges in urban expressways where buildings and houses are approaching.

The expansion joint removal method process conceptual diagram. The perspective view of a cutting line formation process. The perspective view in the state where cutting line formation was completed. The top view which shows the example of arrangement | positioning of a circular cutting groove and a pit. The side view of an example of a wire saw cutting machine.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Expansion joint 2 Cutting groove 22 Auxiliary cutting line 3 Pit 4 Cutting line 5 Wire saw cutting machine 53 Wire saw

Claims (4)

A cutting groove surrounding the expansion joint is formed in the concrete floor slab. The corner of this cutting groove is removed with a core drill and the cylindrical core is left without being removed, and a wire saw is installed in the cutting groove to place the concrete floor. A method for removing an expansion joint by horizontally cutting the plate and the expansion joint. 2. The method for removing an expansion joint according to claim 1, wherein a pit is provided for installing a pulley for guiding the wire saw at an appropriate position of the cutting groove. 3. The method for removing an expansion joint according to claim 2, wherein a plurality of cutting lines are formed in parallel at the pit formation position and are crushed. The removal method of the expansion joint in any one of Claims 1-3 which forms the auxiliary | assistant cutting line parallel to an expansion joint inside the formed cutting groove.