JP2010222809A - Method for refilling inside of cable sheath of existing prestressed concrete (pc) structure with grout - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for refilling the inside of a cable sheath of an existing PC structure with grout, which enables complete refilling to be performed, without leaving an air lock, by a grout-unfilled portion in the sheath for insertion of a prestressing (PC) tendon in the existing PC structure. <P>SOLUTION: In an air lock generation-expected position, there is the risk of having air trapped in the grout-unfilled portion 12 even by grout pressure injection performed by the grout pressure injection device 20, when the grout is pressurized and injected from a grout pressure injection port 13 by the grout pressure injection device 20 after the grout-unfilled portion 12 is decompressed. A branch passage, which is made of a vacuum pressure-resistant material and which communicates and branches off upward, is preprovided in the air lock generation-expected position; a vacuum pressure-resistant container 30 is attached to the branch passage; and the air in an air lock generation-expected portion and the grout around it are sucked in under suction pressure from the inside of the vacuum pressure-resistant container 30 immediately before the completion of the pressure injection of the grout by the grout pressure injection device. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a cable sheath in an existing PC structure that enables more complete grout filling when refilling grout in a grout unfilled portion in a sheath for inserting a PC tendon material in an existing post-tension type PC structure. It relates to a method for refilling grout inside.

  In general, a post-tension type PC structure introduces pre-stress by inserting a PC tension material into a PC tension material insertion sheath installed in the structure and tensioning the PC tension material after the concrete of the structure is hardened. In this way, the grout is filled in the gap in the sheath for inserting the PC tendon after introduction of the prestress.

  In recent years, early deterioration such as cracking, peeling and reinforcing steel corrosion has become a serious problem in concrete structures, and it is no exception in PC structures that do not cause cracking by applying prestress. A particular problem with PC structures is the corrosion of PC steel, the main cause of which is PC grout failure, and deterioration damage due to the quality of the initial PC grout material and poor grout filling during construction. Corrosion and breakage of PC steel occurred. This became apparent from the late 1980s to the 1990s. However, it has reached today with insufficient measures.

  On the other hand, recent advances in non-destructive inspection methods have made it easier to inspect grout-filled parts and refill grout-unfilled parts. A method of refilling the grout to the part has been developed. Mainly, there are a press-fitting method (for example, Non-Patent Document 1) and a vacuum grout method using a vacuum pump (for example, Non-Patent Document 2 and Patent Document 1).

The press-fitting method estimates grout unfilled locations, drills holes at two locations on both ends of the section, confirms ventilation between the drilled holes, and then injects one hole and discharges the other. As a method of performing pressure injection of grout. In the vacuum grout method, a discharge port and a grout pressure injection port are formed in the unfilled part of the grout, and the inside of the sheath for inserting the PC tendon is reduced by a vacuum pump from the discharge port, and the grout pressure injection is performed while maintaining the reduced pressure state. The grout is press-fitted by a pressure pump from the inlet, and the injection is stopped after the grout is discharged from the outlet.
PC grout reinfusion repair manual (draft) Railway Technical Research Institute Kawada Technical Report Vol. 23 2004 Pages 56-61 Repair and reinforcement work for road bridge PC girders JP 2005-23567 A

    In the above-described conventional refilling method, the closer the grout pressure inlet and outlet are to the end of the grout unfilled part, the more complete the refilling can be. In the method, the boundary between the unfilled portion of the grout and the filled portion in the existing sheath for inserting the PC tendon cannot be accurately known, and therefore, both end portions separated from between the grout pressurizing inlet and the outlet. There is a problem that a grout unfilled portion remains.

  In view of the above-described conventional problems, the present invention is an existing PC structure that can be completely refilled without leaving an air pocket in a grout unfilled portion in a sheath for inserting a PC tension member in an existing PC structure. It was made for the purpose of providing a method for refilling grout into a cable sheath of an object.

    In order to solve the above-mentioned conventional problems and achieve the intended purpose, the invention according to claim 1 is characterized in that the grout is not filled in the sheath for inserting the PC tendon in the existing post-tension type PC structure. A grout pressure injection port for injecting grout into the grout unfilled portion and a discharge port for discharging air in the grout unfilled portion are formed in the grout pressure filling device. In the method of refilling the grout into the cable sheath in the existing PC structure in which the grout is pressure-injected by the grout, the grout unfilled portion in the sheath for inserting the PC tension material is also obtained by the grout pressure injection by the grout pressure injecting device A component made of a vacuum pressure-resistant material that branches in advance upwards to the expected air pocket where air can be trapped. A passage is provided, a vacuum pressure vessel is connected to the branch passage, and a vacuum pump is connected to the discharge port, and then the grout pressure is increased while the grout unfilled portion and the vacuum pressure vessel are decompressed by the vacuum pump. The grouting pressurization injection apparatus starts the grouting pressure injection by the injection apparatus, waits for the grouting to be discharged from the discharge opening, closes the opening / closing valve of the discharge opening, and sucks the grout into the vacuum-resistant container. It is to continue pressurization by.

  The invention according to claim 2 is characterized in that a grout pressure injection port for injecting grout into the grout unfilled portion in the PC tension material insertion sheath in the existing post-tension type PC structure. And a discharge port for discharging the air in the unfilled portion of the grout, and grout is reintroduced into the cable sheath in the existing PC structure in which grout is pressurized and injected from the grout pressure injection port by a grout pressure injection device. In the filling method, it is communicated upward in advance to an anticipated position of an air pool where air may be trapped in an unfilled portion in the sheath for inserting the PC tendon material even by grout pressure injection by the grout pressure injection device. When a branch path made of a vacuum-resistant material that branches is provided, and a vacuum-pressure vessel communicates with the branch path via an on-off valve Further, a vacuum pump is communicated with the discharge port via an on-off valve, and then the unfilled portion and the inside of the vacuum pressure resistant vessel are depressurized by the vacuum pump, and the branching is performed when the depressurization degree reaches a predetermined value. Close the on-off valve of the passage, seal the vacuum pressure resistant container, start the pressure injection of the grout by the grout pressure injection device while continuing the pressure reduction by the vacuum pump, and wait for the discharge of the grout from the discharge port Opening the on-off valve of the branch path and reducing the pressure inside the branch path is to suck the air in the expected portion of the air accumulation into the vacuum pressure resistant container and the surrounding grout into the vacuum resistant container. .

  According to a third aspect of the present invention, there is provided a grout pressure injection port for injecting grout into the grout unfilled portion in the sheath for inserting the PC tendon material in the existing post-tension type PC structure. And a discharge port for discharging the air in the unfilled portion of the grout, and grout is reintroduced into the cable sheath in the existing PC structure in which grout is pressurized and injected from the grout pressure injection port by a grout pressure injection device. In the filling method, it is communicated upward in advance to the predicted position of the air pool where air may be trapped in the grout unfilled portion in the PC tension material insertion sheath even by the grout pressure injection by the grout pressure injection device. A branch passage made of a vacuum-resistant material that branches off is provided, and a vacuum-resistant container with a reduced pressure inside is opened in the branch passage. A vacuum pump is connected to the discharge port via an on-off valve and is attached via a valve, and then the grouting by the grouting pressure injection device is performed while the grouting unfilled portion and the vacuum-resistant container are depressurized by the vacuum pump. The pressure in the branch path is reduced by opening the on-off valve of the branch path after waiting for the discharge of the grout from the discharge port, and the air in the expected portion of the air pool and the surrounding grout are reduced. The purpose is to suck into the vacuum-resistant container.

  A feature of the invention described in claim 4 is that a grout pressure injection port for injecting grout into the grout unfilled portion in the sheath for inserting the PC tendon material in the existing post-tension type PC structure. And a discharge port for discharging the air in the unfilled portion of the grout, and grout is reintroduced into the cable sheath in the existing PC structure in which grout is pressurized and injected from the grout pressure injection port by a grout pressure injection device. In the filling method, it is communicated upward in advance to the expected position of the air pool where air may be trapped in the grout unfilled portion in the PC tension material insertion sheath even by the grout pressure injection by the grout pressure injection device. A branch passage made of a vacuum-resistant material that branches off is provided, and the vacuum-pressure vessel with the internal pressure reduced is opened and closed in the branch passage. And an opening / closing valve is attached to the discharge port, and then the pressure injection of the grout by the grout pressure injection device is started, and after waiting for the grout to be discharged from the discharge port, the discharge is performed. By closing the outlet on-off valve and opening the on-off valve of the vacuum-resistant container, the inside of the branch passage is depressurized, and the air in the anticipated portion of the air accumulation and the surrounding grout are sucked into the vacuum-resistant container. It is in.

  The feature of the invention described in claim 5 is that, in addition to the configuration of any one of claims 3 and 4, the vacuum resistant container uses a see-through material whose inside can be seen through all or a part thereof. The vacuum-resistant container is sealed in a pre-depressed state, and the vacuum-resistant container is communicated with the branch passage via an on-off valve at the construction site, and the on-off valve is opened. This is to depressurize the inside of the branch path.

  According to a sixth aspect of the present invention, in addition to the structure of any one of the first to fourth or fifth aspects, the vacuum pressure resistant container is a transparent pressure resistant container made of synthetic resin or glass. Another object of the present invention is to use a vacuum pressure-resistant synthetic resin container in which an intake / exhaust passage opened and closed by an opening / closing valve is connected to the container.

  In the present invention, in advance toward the predicted position of the air pool where air may be trapped in the grout unfilled portion in the PC tendon insertion sheath even by the grout pressure injection by the grout pressure injection device. A branch passage made of a vacuum pressure-resistant material that communicates and branches is provided, a vacuum pressure vessel is connected to the branch passage, and pressure injection by a grout pressure injection device is performed while the vacuum pressure vessel is decompressed. As a result, the air in the portion where the air pocket is formed and the surrounding grout are sucked into the vacuum pressure resistant container only by the pressure reduction and pressure injection in the conventional unfilled portion of the grout, and the grout is regenerated without the air pool. Can be filled.

  In addition, a vacuum-resistant container with a reduced pressure inside is attached via an on-off valve, and a vacuum pump is connected to the discharge port, and then the grout unfilled part and the vacuum-resistant container are filled by the vacuum pump. While the pressure is reduced, the pressure injection of the grout is started by the grout pressure injection device, and the inside of the branch path is decompressed by opening the opening / closing valve of the branch path after waiting for the discharge of the grout from the discharge port, thereby generating an air pocket. The air in the anticipated part may be sucked into the vacuum-resistant container. In this case, the reduced pressure state in the vacuum-resistant container is formed under the control of the factory, so the work reliability is guaranteed. it can.

  Furthermore, the vacuum-resistant container used in the present invention is made of a transparent material that can be seen through in its entirety or in one part, and the inside of the vacuum-resistant container is previously sealed in a depressurized state. In addition, the vacuum pressure-resistant container is communicated with the branch path via an on-off valve at the construction site, and the inside of the branch path is decompressed in advance by opening the on-off valve. The vacuum-resistant container can be easily brought into the field, and the container can be reused and is highly economical. Moreover, the removal status of the air pocket can be easily grasped by visually observing the discharge of the grout into the vacuum pressure resistant container.

  Further, the vacuum pressure resistant container used in the present invention is a transparent pressure resistant container made of synthetic resin or glass, and the vacuum pressure resistant synthetic resin container in which an intake / exhaust passage opened and closed by an on-off valve is connected to the container. By using, the container can be washed and reused, and it is lightweight and easy to transport, improving workability on site.

  Embodiments of the present invention will be described with reference to the drawings of the embodiments.

  First, the grout unfilled portion in the PC tendon insertion sheath in the existing PC structure is searched. Unfilled places are likely to occur near the end fixing part of the PC tendon material, the pre-flow section (parts that mainly occur in the downward inclined part and the grout does not fill the sheath), the horizontal part, etc. .

  In addition, as the appearance of the concrete structure when there is an unfilled part in the sheath for inserting PC tendon, water penetration, wetting along the sheath, cracks, and free lime are observed, so these parts are emphasized. Exploring.

  Any of the following methods or a combination of a plurality of methods can be used as the exploration method.

1. X-ray transmission method The grout filling state is inspected using a high-power X-ray generator. By combining image processing with a digital X-ray inspection system, high-precision inspection can be performed. However, this has problems such as a large-scale device, legal restrictions on handling, and a limit in detection depth.

2. Electromagnetic radar method A technology that confirms the position by radiating electromagnetic waves from the concrete surface into the interior, receiving the reflected waves from the object, and processing the images.

3. Broadband ultrasonic method By transmitting a broadband (2.5 to 1000 kHz) ultrasonic wave at a time, frequency adjustment work becomes unnecessary and work efficiency is improved. Measurement from one direction is possible. Grout filling exploration is possible if the cover thickness to the sheath is within 26 cm.

4). Shock elastic wave method This method measures the elastic waves reflected by vibrations from impacts in voids and reinforcing bars, and determines internal defects based on the strength of the waveform. The degree of filling can be determined relatively easily by visualizing the obtained waveform by spectral imaging.

5). Magnetic exploration method This is a method of detecting a magnetic change that occurs at a fracture location by supplying a magnetic field from a magnet to a PC steel material.

  The grout unfilled portion is identified by the above-described exploration method, and the surface of the PC structure corresponding to the positions assumed to be both ends thereof is marked.

  Next, as shown in FIGS. 1 and 2, from the surface of the PC structure 10, the grout pressure injection port 13 leading to the grout unfilled portion 12 in the PC tendon material insertion sheath 11 and the air in the unfilled portion 12 are supplied. A discharge port 14 for suction and a branch port 15 that leads to the upper side of the predicted position of occurrence of air accumulation after refilling grout are formed by drilling.

  When the grout unfilled portion 12 is inclined in one direction as shown in FIG. 1, this hole is formed with a grout pressure injection port 13 on the side surface near the lower end of the inclination, The discharge port 14 is formed on the side surface near the end of the. In this case, since the expected position of air accumulation after refilling the grout is on the upper end side from the discharge port 14 of the grout unfilled portion 12, the upper surface of the branch port 15 is closer to the end portion above the discharge port 14. It is preferable to set it as the side or the side.

  In addition, when the grout unfilled portion 12 is in a downward arc shape whose center is low and both ends are high, or when the length is horizontal and large, as shown in FIG. The discharge port 14 is formed on both ends, and the branch port 15 is formed on the end side from the discharge port 14.

  As a drilling method, there are a core drill method and a water jet method. Core drills are at risk of steel damage. Therefore, a water jet drilling method is desirable, and the apparatus disclosed in Japanese Patent No. 3388127 can be used.

  After forming the respective mouths 13, 14, and 15 in this way, the ventilation is confirmed, and the inside of the grout unfilled portion 12 is observed with a fiber scope, and is dry or wet, is there water, is the steel wire healthy? And grasp the current state of whether rust is generated or broken. If water is contained, the lowest position is drilled to drain water, and if it is difficult to drain water, dry air is sent from the grout pressure inlet to remove moisture in the sheath.

  Next, a grout injection hose 16 is attached to the grout pressure injection port 13, a vacuum suction hose 17 is attached to the discharge port 14, and a vacuum suction hose 18 is attached to the branch port 15. Tetron blade hoses can be used as these hoses. In addition, it is sealed with a putty or the like when mounting.

  The grout injection hose 16 communicates with the grout pressurization injection apparatus 20 through an on-off valve 22, and the vacuum suction hose 17 at the discharge port 14 communicates with the vacuum pump 21 through the on-off valve 23. Further, a vacuum-resistant container 30 is communicated with the vacuum suction hose 18 of the branch port 15 via an opening / closing valve 32. A vacuum gauge 34 that displays the internal pressure is attached to the vacuum pressure vessel 30.

  Next, the opening / closing valve 23 of the discharge port 14 and the opening / closing valve 32 of the vacuum pressure resistant container 30 are opened, the opening / closing valve 22 of the other grout pressurizing and injection device 20 is closed, and the vacuum pump 21 is operated. The vacuum state is confirmed by crushing the vacuum gauge 34 or the hose. Since the vacuum-resistant container 30 communicates with the unfilled portion 12 of the grout and is decompressed together, the vacuum gauge 34 can know the degree of vacuum in the unfilled portion 12 of the grout.

  When it is confirmed that the desired vacuum state (reduced pressure state), specifically, -0.09 Mpa is reached on the cage pressure display, the on-off valve 22 is opened and the grout pressurizing / injecting device 20 is operated to start grout refilling. To do. At this time, the vacuum pump 21 is kept operating. As a result, the grout a is injected into the unfilled grout portion 12 in the decompressed state, and is discharged from the outlet 14 as shown in FIG. When the discharge of the grout a from the discharge port 14 is confirmed, the on-off valve 23 of the vacuum pump 21 is closed and the operation of the vacuum pump 21 is stopped.

  The pressure injection from the grout pressure injection device 20 is continued. At this time, since the inside of the vacuum pressure resistant container 30 is in a decompressed state, as shown in FIG. 4, the air on the branch port 15 side is sucked from the discharge port 14, and the grout that reaches the periphery of the discharge port together with this air is It is sucked into the container 30. When it is confirmed that the grout has risen into the vacuum-resistant container 30 and the hose 18 has been crushed, the on-off valve 32 is closed.

  After that, pressurization by the grout pressure injection device 20 is continued until it reaches about 0.5 Mpa, and then the on-off valve 22 of the grout pressure injection device 20 is closed, and the grout is cured in a pressurized state. Check filling.

  In addition, as the vacuum-resistant container 30, the thing of the structure shown in FIG. 5 can be used. This uses a transparent plastic or glass pressure-resistant container. Examples of the synthetic resin material that can be used for the container include acrylic, polyethylene, and polycarbonate.

  The vacuum pressure resistant container 30 includes a top-opening container body 30a and a sealing lid 30b that opens and closes the top opening, and a body portion of the container body 30a is provided with an intake / exhaust passage 31 communicating with the inside. The intake / exhaust passage 31 is provided with an open / close valve 32. The tip of the intake / exhaust passage 31 serves as a joint portion 33 that communicates the tip of the vacuum suction hose 18 communicated with the aforementioned branch port 15.

  In the above-described embodiment, the grout unfilled portion 12 and the vacuum pressure resistant vessel 30 are depressurized by the vacuum pump 21 and when the depressurization degree reaches a predetermined value, the grout pressurizing device 20 pressurizes the grout. In addition to this, in addition to this, the vacuum pump 21 is used to depressurize the unfilled portion and the vacuum pressure resistant container 30 and when the degree of decompression reaches a predetermined value, the vacuum resistant container 30 is opened and closed. With the valve 32 closed and the vacuum pressure resistant vessel 30 sealed, the pressure injection of the grout by the grout pressure injecting device 20 is started, and after waiting for the discharge of the grout from the discharge port 14, the valve for opening and closing the vacuum pressure resistant vessel is started. May be opened to depressurize the inside of the branch path.

  Further, in each of the embodiments described above, the reduced pressure in the vacuum-resistant container 30 is reduced together with the grout unfilled portion 12 by the vacuum pump 21 communicated with the discharge port 14. The inside is depressurized in advance to a degree of vacuum necessary for removing air pools using a vacuum pump at the site or a factory with a depressurization facility. This is carried onto the PC structure 10 described above, and the vacuum suction hose 18 from the branch port protruding on the structure 10 is connected to the joint portion 33 in a state of being airtight. In this state, after reducing the pressure by the vacuum pump 21 and the pressure injection of the grout by the grout pressure injection device 20 as described above, confirming the discharge of the grout from the discharge port 14, and closing the on-off valve 22 of the vacuum pump 21, The on-off valve 32 of the intake / exhaust passage 31 is opened. As a result, air on the branch port 14 side is sucked from the discharge port 14, and the grout reaching the periphery of the discharge port together with this air may be sucked into the vacuum-resistant container 30.

  Furthermore, it can also be carried out in the conventional press-fitting method described above. In this case, only the on-off valve 23 is attached to the discharge port 14 in the embodiment shown in FIGS. 1 and 2 without using a vacuum pump. Further, the vacuum pressure resistant vessel 30 is provided with an on-off valve 32, and is used by carrying in a pressure reduced to a desired degree of vacuum in advance.

  With the on-off valve 23 open, the grout pressurization and injection device 20 starts pressurizing the grout, waits for the grout from the outlet 14 to be discharged, and closes the on-off valve 23 of the outlet 14. By opening the on-off valve 32 of the vacuum pressure resistant container 30, the inside of the branch path is depressurized, and the air and the surrounding grout are sucked into the vacuum pressure resistant container.

  As described above, when using the vacuum-resistant container 30 that has been previously decompressed by a decompression facility such as a vacuum pump, a simple container can be used without requiring a pressure gauge for each container. Since the decompressed vacuum pressure resistant container 30 can be carried in and used, the decompression time at the construction site is shortened.

It is sectional drawing which shows schematic structure of the apparatus of the example which enforced the method of this invention. It is sectional drawing which shows schematic structure of the apparatus of another example same as the above. It is a partial expanded sectional view which shows the state in the middle of grout refill in the method of this invention. It is a partial expanded sectional view which shows a grout refill completion state same as the above. It is a longitudinal cross-sectional view which shows an example of the vacuum-resistant container used for this invention.

a grout 10 PC structure 11 PC tension material insertion sheath 12 grout unfilled portion 13 grout pressure injection port 14 outlet 15 branch port 16 grout injection hose 17, 18 vacuum suction hose 20 grout pressure injection device 21 vacuum pump 22 , 23 On-off valve 30 Vacuum-resistant pressure vessel 30 a Container body 30 b Sealing lid 31 Intake / exhaust passage 32 On-off valve 33 Joint portion 34 Vacuum gauge

Claims (6)

A grout pressure injection port for injecting grout into the grout unfilled portion and air in the grout unfilled portion are discharged into the grout unfilled portion in the sheath for inserting the PC tendon material in the existing post-tension type PC structure. In the grout refilling method into the cable sheath in the existing PC structure in which the grout pressure injection port is formed and the grout is pressurized and injected by the grout pressure injection device.
The resistance to branching upward in advance to the predicted position of the air reservoir where air may be trapped in the grout unfilled portion in the PC tendon insertion sheath also by the grout pressure injection by the grout pressure injection device. A branch passage made of a vacuum pressure material is provided, and a vacuum pressure vessel is connected to the branch passage, and a vacuum pump is connected to the discharge port, and then the grout unfilled portion and the vacuum pressure vessel are evacuated by the vacuum pump. The pressure injection of the grout by the grout pressure injection device is started while the pressure is reduced, the grout is discharged from the discharge port, the opening / closing valve of the discharge port is closed, and the grout is sucked into the vacuum-resistant pressure vessel. The grout refilling method in the cable sheath in the existing PC structure characterized by continuing the pressurization by the grout pressure injection device until A grout pressure injection port for injecting grout into the grout unfilled portion and air in the grout unfilled portion are discharged into the grout unfilled portion in the sheath for inserting the PC tendon material in the existing post-tension type PC structure. In the grout refilling method into the cable sheath in the existing PC structure in which the grout pressure injection port is formed and the grout is pressurized and injected by the grout pressure injection device.
Anti-vacuum for branching upward in advance to the expected position of the air pool where air may be trapped in the unfilled portion in the sheath for inserting the PC tendon even by the grouting pressure injection by the grouting pressure injection device A branch passage made of a pressure-sensitive material is provided, and a vacuum-proof container is connected to the branch passage via an on-off valve, and a vacuum pump is connected to the discharge port via the on-off valve. The inside of the filling part and the vacuum pressure resistant container is depressurized, and when the degree of decompression reaches a predetermined value, the branch valve is closed to seal the vacuum resistant container, and the decompression by the vacuum pump is continued. Initiating pressure injection of grout by the grout pressure injection device, waiting for the discharge of grout from the outlet, opening the branch valve, and reducing the pressure in the branch path A method for refilling a grout unfilled portion in an existing PC structure, characterized in that air in a portion where air accumulation is expected to occur in the vacuum-resistant vessel and the surrounding grout are sucked into the vacuum-resistant vessel . The grout pressure filling inlet for injecting grout into the grout unfilled portion and the air in the grout unfilled portion are discharged into the grout unfilled portion in the sheath for inserting the PC tendon material in the existing post-tension type PC structure. In the method for refilling grout into the cable sheath in the existing PC structure in which the grout pressure injection port is formed and the grout pressure injection device is used to press-inject the grout from the grout pressure injection port.
Anti-vacuum that branches in advance upwards to the predicted position of the occurrence of air pool where air may be trapped in the grout unfilled portion in the sheath for inserting PC tension material also by the grouting pressure injection by the grouting pressure injection device A branch passage made of a pressure-resistant material is provided, and a vacuum pressure-resistant container with a reduced pressure inside is attached to the branch passage through an on-off valve, and a vacuum pump is connected to the discharge port through the on-off valve. In addition, the grouting pressure injection device starts the grouting pressure injection while the grouting pressure filling device is decompressed by the vacuum pump and waits for the grouting from the discharge port to open and close the branch path. By opening the valve, the inside of the branch passage is depressurized, and the air in the anticipated portion of the air pool and the surrounding grout are sucked into the vacuum-resistant container. Grout refilling method into the cable sheath in the existing PC structure formed as a feature. A grout pressure injection port for injecting grout into the grout unfilled portion and air in the grout unfilled portion are discharged into the grout unfilled portion in the sheath for inserting the PC tendon material in the existing post-tension type PC structure. In the grout refilling method into the cable sheath in the existing PC structure in which the grout pressure injection port is formed and the grout is pressurized and injected by the grout pressure injection device.
Anti-vacuum that branches in advance upwards to the predicted position of the occurrence of air pool where air may be trapped in the grout unfilled portion in the sheath for inserting PC tension material also by the grouting pressure injection by the grouting pressure injection device A branch passage made of a pressure-resistant material is provided, and a vacuum-resistant container with a reduced pressure inside is attached to the branch passage through an on-off valve and an on-off valve is attached to the discharge port, and then the grout pressure injection The apparatus begins to pressurize the grout by the apparatus, waits for the grout to be discharged from the discharge port, closes the open / close valve of the discharge port, and opens the open / close valve of the vacuum pressure resistant container. In an existing PC structure characterized by sucking air in a portion where air pool is expected to occur and surrounding grout into a vacuum-resistant vessel. Grout re-filling method into the Burushisu.   The vacuum-resistant container is made of a transparent material that can be seen through in its entirety or in part, and the vacuum-resistant container is sealed in a state where the vacuum-resistant container has been previously depressurized, and the vacuum-resistant container is used at the construction site. The PC tension member in the PC structure according to any one of claims 3 and 4, wherein a vacuum pressure vessel is communicated with the branch passage via an on-off valve, and the inside of the branch passage is decompressed by opening the on-off valve. Injecting grout into the insertion sheath.   2. The vacuum pressure resistant container is a transparent pressure resistant container made of synthetic resin or glass, and uses a vacuum pressure resistant synthetic resin container in which an intake / exhaust passage opened and closed by an opening / closing valve is connected to the container. A method for injecting grout into a PC tendon insertion sheath in the PC structure according to any one of -4 or 5.

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