JPH07173820A - Method of opening reinforced concrete levee body for dam - Google Patents

Abstract

PURPOSE:To bore an opening having a required size accurately in a reinforced concrete levee body for a dam having a thickness more than 1m so that troublesome destruction has no influence on surroundings and to make it possible to remove a cut and separated columnar body in the opening. CONSTITUTION:A scaffolding 2 is assembled at a downstream side of a reinforced concrete levee body for a dam having thickness more than 1m. Cable through holes 3a, 3b, 3c and 3d are bored in the direction of the thickness in corner sections around an opening area in the reinforced concrete levee body 1 with a core drill. A cutting cable 10 passes through adjacent cable through holes through guide pulleys 12, 13a and 13b under running speed and tension adjustment and, at the same time, a reinforced concrete wall is cut while injecting water and running, driving and retreating the cutting cable with a cable driving device. The cut and separated columnar body is crushed and removed.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to dam rebar concrete.
A dam rebar concrete dam body for accurately drilling an opening of the required size so as not to damage the surroundings and removing the separated pillars of the opening. Related to the opening method. [0002] Conventionally, prior to crushing and removing an opening of a reinforcing bar concrete dam body of a dam, in order to cut the periphery of the opening, a grooving machine is used along the circumference of the opening area. A slot at the depth of the slot, a slot-shaped free surface is formed, a hole is drilled in the block divided by the free surface, and a hydraulic crusher is inserted into this to excavate or Crushing was performed with a crushing agent. However, in the above-mentioned conventional opening method, not only a large number of reinforcing bars cannot be cut at the same time due to the limit of cutting or drilling ability derived from the structure and mechanism of the cutter or drill used therein, but The cut surface was wavy, and an accurate and smooth opening surface was not formed in the reinforcing concrete wall. Further, since the opening surface is a rough surface, there is a drawback that a large amount of labor is required to remove the columnar body that has been cut and separated. An object of the present invention is to accurately form an opening of a required size in a rebar concrete dam body of a dam having a thickness of 1 m or more so as not to cause an undesired damage to the surroundings. Another object of the present invention is to provide a method for opening a reinforcing bar concrete dam body of a dam capable of removing the columnar body that has been cut and separated. In order to solve the above problems, the present invention provides a step of forming a scaffold on the downstream side of a reinforced concrete dam body of a dam having a thickness of 1 m or more, and an opening in the reinforced concrete dam body. A step of drilling a cable through hole in the thickness direction by a core drill at each corner around the area, and a cutting cable running through a guide pulley in each adjacent cable through hole.
The cable is passed under the control of running speed and tension, and while the water is being poured, the cable driving device drives the cutting cable to run and retreat, cutting the reinforcing bar concrete wall and crushing and removing the separated pillars. The process consists of: First, a scaffold corresponding to the height at which a cable through hole is formed so as to penetrate through the reinforced concrete wall of the dam is assembled on the downstream side of the reinforced concrete dam body of the dam. Next, in the cable through hole step, a cable through hole is drilled using a core drill so as to penetrate the reinforcing bar concrete levee body. For example, when the opening area is a quadrangle, a total of four cable through holes are formed at each corner of the reinforcing bar concrete levee.
Since the opening area is not limited to a quadrangle, the cable through holes are formed according to the number of corners. Next, in the step of cutting between the adjacent cable through holes by wire sawing, all of the adjacent cable through holes in the reinforcing bar concrete dam body, in other words, the entire circumference of the opening area is the front side. To the back side, the inner columnar part surrounded by each cut surface, that is, the columnar part having a square columnar shape or a rectangular parallelepiped whose opening area is, of course, completely separated from the surrounding bank, Is cut to form a cutting gap. In such wire sawing, as long as it can be circulated through the cutting cable, it does not matter whether the opening is large or small. As the cutting cable, for example, beads having a diamond abrasive layer on a wire rope, a coil spring, etc. The spacers are alternately inserted, and a stopper made of a steel ring or the like is crimped at predetermined intervals. As the cable drive device, for example, a cable drive pulley for running a wound cutting cable and a rotary drive mechanism for the cable drive pulley, and a drive wheel for moving on a rail or a drive pinion. What is adapted to move on the rack according to the above may be appropriately used. When the cable driving device is operated during the above-mentioned wire sawing, the cutting cable circulates while being urged to the required tension, and the cutting cable is passed through so that the adjacent cables pass through. A break is made between them. The tension of the cutting cable can be maintained and adjusted as the wire sawing progresses, for example, by gradually moving the cable drive pulley rearward along the rail or rack, while fixing the cable drive pulley. Alternatively, another tension pulley may be gradually moved. [0012] The cutting cable, as seen in rope conduction and belt conduction, can be bent freely through the guide pulley in the middle without being hindered from traveling, and can be arranged at a free length. Since it is possible, by arranging the guide pulley appropriately according to the positional relationship between the reinforced concrete dam and the cable drive device, obstacles in the middle, vertical cutting, horizontal cutting, inclined cutting and other cutting forms, it is possible to freely It can be provided. After the cutting cable is once arranged between the reinforced concrete drive device and the reinforced concrete drive device, the cutting operation is performed by the cable drive device until it is completely cut, including the internal reinforcing bar. Since it is controlled by the above, it is not necessary for the cutting worker to constantly engage in the cutting work at the cutting site as in the past, and it is easy to introduce automatic operation. The running speed and tension of the cutting cable are appropriately selected depending on the cutting conditions of the reinforced concrete dam body to be cut, but normally, the running speed is 20 to 3
0m / sec, tension on the tension side is 50 to 150k
It is about g, and under these cutting conditions, the reinforced concrete dam body is completely cut including the internal reinforcing bars. In the above-mentioned wire sawing, it is necessary to inject water into a cutting point or a cutting cable for cooling, lubrication, cleaning and the like. As the water injection method, for example,
From the water absorption nozzle inserted at the end of the cable through hole, supply water into the hole, or into the cable through hole,
Water may be discharged to the cutting point or the cutting cable from a water sprinkler arranged in the cable passage hole so as not to come into contact with the cutting cable. In that case,
When the reinforced concrete wall body to be opened is partially or entirely underwater, for example, a reinforced concrete dam body of a dam, the water around it can be used for water injection. In the last step of removing the columnar body that has been cut and separated, a concrete cutter and other equipment and devices are appropriately used together to crush the columnar portion into a size that can be carried out, and then the columnar portion is sequentially discharged to the outside. After removal of the body is the opening. In this step, the columnar body to be crushed in the previous step is completely cut and separated from the surrounding wall body in advance, the edge is cut, and the cutting gap is formed, so that the entire columnar body is not pulled out by pressing or pulling. It is possible. However, in this step of the present invention, in order to partially take out the crushed columnar portion to the outside, it is possible to use partial withdrawal by pressing or pulling together. If the wire sawing is performed so that the reinforced concrete wall body is slightly tapered in the thickness direction, the entire planar body can be easily pulled out by pressing or pulling. Embodiments of the present invention will be described with reference to the drawings. As shown in the front and side views of FIGS. 1A and 1B, respectively,
A scaffold 2 is assembled on the downstream side of the reinforced concrete wall body 1, and cable through holes 3a, 3b, 3c, 3d are bored by core drills at the respective corners of the rectangular opening area. Next, as shown in the side view and the plan view of FIGS. 2A and 2B, and the side view and the plan view of FIGS. 3A and 3B, respectively, a rail 4 is laid on the scaffold 2 and the rail 4 is provided. The cable driving device 5 is movably inserted in the cable. The cable driving device 5 includes a cable driving pulley 6 and a rotation driving mechanism (not shown), a tension side tension pulley 7 and a slack side tension pulley 8 adjacent to the cable driving pulley 6, and a drive which is further fitted to the rail 4. The wheel 9 and its rotation drive mechanism (not shown) are provided. First, as shown in FIGS. 2A and 2B, the cutting cable 10 is passed through the cable through holes 3a and 3b so as to be wound around it, and the tension side tension pulley 7 and the slack side tension pulley 7 in the cable driving device 5 are wound. Endlessly hangs on the cable drive pulley 6 through each inside of 8. When the cable drive pulley 6 and the drive wheels 9 of the cable drive device 5 are actuated in such a state, the cable drive pulley 6 moves rearward along the rail 4 while rotating, and therefore, for cutting. The cable 10 runs endlessly with a required tension and is vertically cut between the cable through holes 3a and 3b in the reinforced concrete dam body 1. Then, the cable through holes 3c and 3d are also vertically cut in the same manner as described above. Next, as shown in FIGS. 3A and 3B, the cutting cable 10 is inserted into the cable through holes 3b and 3c,
The cable is passed through so as to be wound around, and passed through the guide pulley base 11 and the tension side tension pulley 7 and the loose side tension pulley 8 in the cable drive device 5, and is endlessly hung on the cable drive pulley 6. The guide pulley base 11 includes a pair of lateral guide pulleys 1.
2, 12 and two pairs of vertical guide pulleys 13a, 13a and 13b, 13b adjacent to them, respectively, which are anchored to the reinforced concrete wall 1 during wire sawing so as to be detachably anchored after use. In such a state, by operating the cable driving device 5 in the same manner as described above, the cutting cable 10 is endlessly circulated with a required tension, and the cable through hole 3b in the reinforced concrete dam body 1 is provided. ，
Horizontal cutting is performed between 3c. Then, the cable through holes 3a and 3d are also horizontally cut in the same manner as described above. The guide pulley base 11 is provided with the cutting cable 10 passed between the cable through holes 3b, 3c or 3a, 3d.
Two pairs of vertical guide pulleys 1 that are adjacent to each other and are narrowed by a pair of lateral guide pulleys 12, 12.
It guides to the tension side tension pulley 7 and the loose side tension pulley 8 in the cable drive device 5 by 3a, 13a and 13b, 13b. Although not shown, the cable through holes 3a, 3b, 3c, and
Water for cooling, lubrication, etc. is supplied to 3d and other cutting points if necessary. Each cable through hole 3a, 3 as described above
By wire sawing between b, 3c and 3d, FIG.
And, as shown in the front view and the cross-sectional view of FIG. 4B, respectively, the columnar body 14 surrounded by the four cut surfaces is completely separated from the surrounding reinforced concrete dam body 1 and the edge is cut to form a cutting gap. It will be in a state of being. Finally, the columnar bodies 14 are successively crushed and removed by a crusher or the like to form openings 15 as shown in the sectional view of FIG. The invention is not limited to the embodiments described above. For example, the cutting order between the cable through holes may be appropriately selected according to the actual situation, and the above embodiment is merely an example. Further, the cable drive device may be moved in parallel or obliquely with respect to the wall surface of the reinforced concrete dam body, and the cable drive device may be arranged on the reinforced concrete wall body or the like. It is also possible to employ another feed mechanism including a drive pinion and a rack or another tension maintaining mechanism. Further, as a guide pulley for freely guiding and changing the direction of the cutting cable, guide pulleys having a rotation surface in a required direction may not be integrated as described above, but may be separately used as many as a required number. A required number of guide pulley bases having guide pulleys in a combination different from the above may be installed and used on the reinforced concrete wall itself or on the road surface. EFFECTS OF THE INVENTION According to this method, a reinforced concrete dam body having a thickness of 1 m or more is opened safely and accurately with a minimum number of man-hours so as not to cause an undesired damage to the surroundings. Can be drilled in.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1A and 1B are a front view and a side view, respectively, for explaining a step of forming a cable through hole in an opening method for a reinforced concrete wall according to the present invention. 2A and 2B are a side view and a plan view, respectively, for explaining a wire sawing process. 3A and 3B are a side view and a plan view, respectively, for explaining the wire sawing process. 4A and 4B are a front view and a cross-sectional view taken along the line I-I, respectively, for explaining a cut state after wire sawing. 5 is a cross-sectional view taken along the line II of FIG. 4A after the crushing step. [Explanation of Codes] 1 Reinforced concrete dam body 2 Scaffolds 3a, 3b, 3c, 3d Cable through hole 4 Rail 5 Cable drive device 10 Cutting cable 11 Guide pulley stand 14 Columnar body 15 Opening

Claims (1)

(Claims) (1) A step of assembling a scaffold on the downstream side of a reinforced concrete dam body having a thickness of 1 m or more, and a cable is threaded by a core drill to each corner around the opening area of the reinforced concrete dam body. The process of drilling holes in the thickness direction, the cutting cable running through the guide pulley is passed through each adjacent cable through hole while adjusting the running speed and tension, and cutting is performed by the cable driving device while pouring water. A method of opening a rebar concrete dam body for a dam, comprising the steps of cutting the rebar concrete dam body while driving and retreating the power cable and crushing and removing the separated columnar bodies.