JP2007046313A - Method of directly embedding and connecting prestressing steels, and connection structure having binding force relaxing function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of directly embedding and connecting prestressing steels, which dispenses with a space forming shell pipe for a prestressing steel connecting device, simplifies filler injecting work in the construction field, and contributes to quick and simplified field work and reduction of construction costs, and to provide a connection structure having a binding force relaxing function. <P>SOLUTION: There is provided a prestressing steel straining and connecting method for connecting the prestressing steels 4 in a direct embedding manner at a concrete jointed section between an antecedent construction zone A and a subsequent construction zone B, by using the connecting device 1 having a primary side connection portion 2 and a secondary side connection portion 3. When the prestressing steel 4 in the subsequent construction zone B is strained, in order to move the connecting device 1 against a binding force by a bearing pressure of concrete 16, a bearing pressure relaxing means 5 is arranged in association with a terminal of the secondary side connection portion 3, and in order to avoid direct fixture between the connecting device 1 and the concrete 16, a sheathing layer 6 is placed on a peripheral portion of the connecting device 1. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method of directly embedding and connecting PC steel materials for connecting PC steel materials of both work zones under tension by a direct embedding method at the concrete joints of adjacent preceding and succeeding work zones, and implementation of the method. The present invention relates to a connection structure having a restraining force relaxation function that is preferably used.

Conventionally, in a post-tension type prestressed concrete (PC) structure, in a concrete transfer part for connecting PC steel used for prestressing concrete, each PC steel in the preceding work area A and the following work area B is illustrated in FIG. In order to prevent the connecting device 1 from being constrained by the concrete 16 when the PC steel material 4 in the subsequent work section B is tensioned after connecting using the general-purpose connecting device 1 (see Non-Patent Document 1). In addition, as shown in FIG. 4, a space for housing the connecting device 1 is formed in the concrete 16 by using a space forming shell tube 14 commonly called a “coupler sheath”. And after the tension | tensile_strength of the PC steel material 4 of a follow-up work area B, between the PC steel material 4 and the sheath for PC steel materials for preventing it from being restrained by the concrete 16 like the case of the connection apparatus 1 in the case of the tension | tensile_strength. In addition to filling the grout, the space formed by the coupler sheath 14 is also filled with the grout material 15.
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  In addition, the connection of the PC steel materials 4 and 4 by the connection apparatus 1 was performed as follows with reference to FIG. That is, the end portion of the PC steel material 4 embedded in the concrete 16 in the preceding section A is inserted into the sleeve 17 and the wedge 18 is inserted, thereby fixing the end portion of the PC steel material 4 and supporting the joining surface S of the concrete 16. A pressure plate 8 is embedded, and the sleeve 17 is supported by the support pressure plate 8. In this case, the primary side connection portion 2 is formed by the sleeve 17 and the wedge 18. On the other hand, in the succeeding work section B adjacent to the preceding work section A, a compression grip 20 is attached to the end portion of the PC steel material 4, and when the compression grip 20 is fitted into the sleeve 21, a terminal tool is attached to the end portion of the PC steel material 4. Is installed. In this case, the secondary connection portion 3 is formed by the compression grip 20 and the sleeve 21. Each of the sleeves 17 and 21 is formed with an internal thread, and a plug 19 having a screw on the outer periphery is screwed to the sleeves 17 and 21 so that both PC steel materials 4 are connected on the same line.

  By the way, conventionally, as shown in FIG. 4, when placing the concrete 16 in the subsequent work section B, a space is formed by using the coupler sheath 14 that covers the entire connecting device 1, and the tension in the subsequent work section B ends. Thereafter, a grout material 15 such as cement grout is injected into the gap between the space and the connection device 1. In this method, even when the grout material is filled between the PC steel material 4 and the PC steel material sheath after the end of the tension, the pre-grout PC steel material has a feature that does not require the grout material filling after the end of the tension (hardening with time Even in the case of using a special resin and a PC steel coated with a polyethylene sheath, almost the same construction method is used, but FIG. 4 illustrates the case of using a pre-grout PC steel. In addition, when using pregrout PC steel materials, before placing the concrete 16 of the following work area B, it is also performed to fill the coupler sheath 14 with the same resin as used for the pregrout PC steel materials.

  As described above, the use of pre-grout PC steel has made it possible to save labor and improve construction quality. However, in the case of a structure that still requires the use of PC steel connectors, Even if no grout filling is required, the space formed by the coupler sheath 14 in the connecting portion still needs grout filling in the field, which is necessary for promoting labor saving and improvement of construction quality. The hindrance has not changed.

  The present invention has been made to solve such problems, and the object of the present invention is to eliminate the need for a space-forming shell tube for the connecting device for PC steel materials, and to provide an on-site filler. A method of directly embedding and connecting PC steel, which enables the omission of the injection work, thereby promoting the speed and labor saving of the field work and the reduction of the work cost, and the restraining force relaxation function suitably used for the implementation of the method. It is in providing the connection part structure provided.

  In order to solve the above problems, the present invention employs the following configuration.

  That is, the present invention has the following configuration in order to achieve the above object. That is, the invention of claim 1 in the present invention directly uses the connecting device 1 provided with the primary side connecting portion 2 and the secondary side connecting portion 3 at the concrete joint portion of the preceding work section A and the succeeding work section B. In the tension connection method of the PC steel material 4 which connects the PC steel material 4 by the burying method, when the PC steel material 4 in the subsequent work section B is tensioned, the connection device 1 can be moved against the restraining force caused by the bearing pressure of the concrete 16. In order to avoid the direct sticking between the connecting device 1 and the concrete 16 while providing the support pressure relaxation means 5 in relation to the terminal portion of the secondary side connecting portion 3, A method of directly embedding and connecting PC steel characterized by depositing a layer 6.

  In the invention of claim 2 in the present invention, the primary side connection portion 2 and the second side connection portion 2 for connecting the PC steel material 4 under tension by the direct burying method in the concrete joint portion of the preceding work section A and the succeeding work section B. It is a connection part structure attached to the connection apparatus 1 provided with the secondary side connection part 3, Comprising: It forms in the solid board body 7 which can be compressed and consists of a soft material compared with the concrete 16, PC of the following work area B It is characterized by including a support pressure relaxation means 5 formed by being surrounded by a steel material 4 and being attached to a terminal part of the secondary side connection part 3, and a covering layer 6 being attached to the outer peripheral part of the connection device 1. It is a connection part structure provided with the restraint force relaxation function to do.

  In the invention of claim 3 in the present invention, the primary side connecting portion 2 and the second connecting portion 2 for connecting the PC steel material 4 under tension by the direct burying method in the concrete joint portion of the preceding work section A and the succeeding work section B. It is a connection part structure attached to the connection apparatus 1 provided with the secondary side connection part 3, Comprising: The terminal part of the primary side connection part 2 enclosed in PC steel materials 4 of the preceding work area A formed in the hollow disk body of volume unchanged The primary side container 9 interposed between the support plates 8 is formed in a hollow disk body of variable volume by compression, and is attached to the terminal part of the secondary side connection part 3 by being surrounded by the PC steel material 4 in the subsequent work section B. Secondary container 10, pipe 11 connecting both primary and secondary containers 9, 10 along with connection device 1, filling in secondary container 10 and uncured filling that cures over time The support pressure relaxation means 5 made of each member of the material 12 and the outer cover layer formed on the outer peripheral portion of the connecting device 1 A connection part structure comprising a binding relaxation function, which comprises and.

  According to a fourth aspect of the present invention, there is provided the anticorrosion tape 13 in which the outer cover layer 6 is made of a synthetic resin soft tape or the like with respect to the connection portion structure having the restraining force relaxation function according to the second or third aspect. It is the structure formed by winding around the outer peripheral part of the connection apparatus 1 helically.

  Further, the invention of claim 5 in the present invention relates to a connecting portion structure having a restraining force relaxation function according to claim 2 or claim 3, wherein the outer cover layer 6 is a soft tube made of a heat shrinkable synthetic resin tube or the like. It is the structure formed by attaching to the outer peripheral part of the connection apparatus 1. It is characterized by the above-mentioned.

  According to the present invention as described above, when the PC steel material 4 is connected under tension by the direct burying method at the concrete joints in the preceding work area A and the succeeding work area B, the secondary side connection part 3 of the connection device 1 is used. An outer cover layer is formed on the outer peripheral portion of the connection device 1 by a simple method such as attaching the supporting pressure relaxation means 5 having a simple structure in relation to the terminal portion of the wire and winding the anticorrosion tape 13 in a spiral shape. The space forming shell tube for covering the entire connecting device 1 is omitted, and the work for injecting the filler into the space around the connecting device 1 on the spot is sufficient. Is no longer necessary.

  Furthermore, according to the present invention, when tensioning the PC steel material 4 in the subsequent work section B, the support pressure relaxation means 5 exhibits the function of relaxing the binding force to the concrete connection device 1, and at the same time, the concrete connection device. Since the adhesive force to 1 is buffered, the connection device 1 can be smoothly moved along with the tension of the PC steel material 4 while eliminating the need for a filler.

  The present invention has the following effects.

  That is, according to the present invention, in the field work for connecting the PC steel material, the support pressure relaxation means having a simple structure such as a solid board body and the outer cover layer formed by a simple method using the anticorrosion tape or the like are used. As a result, the construction method is simpler and can be processed in a shorter time compared to the conventional work where grout filling work is indispensable. Can be achieved. Moreover, according to the present invention, it is possible to achieve a tension transmission property that is comparable to a conventional method using a coupler sheath, and it is also possible to promote quality improvement for PC steel construction work. Useful.

  Embodiments of the present invention will be specifically described below with reference to the accompanying drawings.

  FIG. 1 is a side view showing a connection state of a connection device including a connection portion structure according to the first embodiment of the present invention. In the first embodiment, the connecting device 1 for connecting the PC steel members 4 stretched in the preceding work section A and the succeeding work section B of the concrete structure under tension is the primary side conventionally used. Various known connection devices including the connection portion 2 and the secondary side connection portion 3 can be used, and the work of tensioning the PC steel material 4 in the preceding section A is performed using the primary side connection portion 2 at the connection end. Next, the PC steel material 4 in the subsequent work section B is connected using the secondary side connection portion 3.

  One of the element members characterizing the present invention for relieving the movement restraint based on the bearing pressure of the concrete at the end of the connecting device 1 opposite to the bearing plate 8, that is, at the end of the secondary side connecting portion 3. The support pressure alleviating means 5 is attached. The support pressure relaxation means 5 in the case of the first embodiment has a compressible solid board 7 made of, for example, a synthetic resin whose outer peripheral shape is the same as or substantially the same as that of the secondary side connection portion 3. In this case, the solid board body 7 is made of a softer material than soft rubber, styrene resin, or similar concrete, and is, for example, a PC steel material in the center having a thickness of 5 to 40 mm. A donut board-like thing with a hole through which 4 is inserted is used, and this is attached to the terminal part of the secondary side connection part 3 or the like.

  On the other hand, on the outer peripheral portion of the connecting device 1, an outer covering layer 6 realized by an anticorrosion tape 13 is attached so as to avoid direct adhesion between the connecting device 1 and the surrounding concrete. As the jacket layer 6, for example, a strip-shaped anticorrosion tape 13 made of a synthetic resin soft tape is wound in a single layer or a plurality of layers in a spiral shape so as to wrap around about a half width, so that the jacket can be easily formed on site. A layer 6 can be provided.

  In 1st Embodiment comprised in this way, it is connected to the PC steel material 4 of the following work area B using the secondary side connection part 3, and the bearing pressure which consists of a solid board body 7 is connected. The relaxation means 5 is attached to the terminal portion of the secondary side connection portion 3, and then the anticorrosion tape 13 is spirally wound to thereby form a connection portion structure having a restraining force relaxation function.

  Then, after the concrete laying in the succeeding work section B is finished, the PC steel material 4 in the succeeding work section B is tensioned, whereby the direct embedment connecting work of the PC steel material 4 is completed. At that time, the external force is applied to the connection device 1 in the direction away from the bearing plate 8 due to the tension of the PC steel material 4 in the subsequent work section B, but the restraining force relaxation function and the anticorrosion tape 13 provided in the compressible solid board body 7 are provided. Combined with the buffering function of the outer cover layer 6, the connecting device 1 can be moved by a required amount without being constrained by the concrete.

  FIG. 2 is a side view showing a connection state of a connection device including the connection portion structure according to the second embodiment of the present invention. FIG. 3 is a perspective view of the primary side container 9 of the element member in the support pressure reducing means 5 shown in FIG. 2 and (b) of the secondary side container 10 in the same manner. The second embodiment is similar to that of the first embodiment described above, and corresponding members are denoted by the same reference numerals, and the description thereof is omitted here.

  The structure characterized in the connection part structure according to the second embodiment is that the supporting pressure relaxation means 5 is formed of a primary side container 9, a secondary side container 10, a pipe 11, and a small amount of filler 12. It is. The primary side container 9 is formed in a hollow plate body having an invariable volume, is surrounded by the PC steel material 4 in the preceding section A, and is interposed between the terminal part of the primary side connection part 2 and the bearing plate 8. The secondary side container 10 is formed in a hollow disk body having a variable volume by compression, is surrounded by the PC steel material 4 in the subsequent work section B, and is attached to the terminal part of the secondary side connection part 3. The pipe 11 is provided so as to connect both the primary side and secondary side containers 9 and 10 along with the connection device 1. The filler 12 is an uncured material of a type that cures over time similar to a grout material, and is filled in the secondary container 10.

  Both the primary side and secondary side containers 9 and 10 are formed in a circular deep dish-like body having, for example, an outer shape substantially the same as that of the connection device 1 or substantially the same shape and having a hole through which the PC steel material 4 passes in the center. The primary container 9 is made of steel and has a volume-invariant structure. The primary container 9 is covered with the bearing plate 8 with its bottom side abutted against it. The secondary container 10 is formed of a steel deep plate-like main body 10A and a resin or steel disc-shaped lid 10B having a thickness of 10 to 40 mm. For example, the lid 10B enters the main body 10A. The lid 10B is attached so that the lid 10B comes into contact with the terminal portion of the secondary side connecting portion 3. The pipe 11 is made of a flexible thin tube made of polyethylene or the like, and extends along the connection device 1 so as to communicate the space portions in both the primary side and secondary side containers 9 and 10.

  The uncured filler 12 similar to that used for the pre-grout PC steel is filled in the main body 10A thus provided. On the other hand, on the outer peripheral portion of the connection device 1, an outer cover layer 6 made of the anticorrosion tape 13 similar to that in the first embodiment is attached. In addition, although illustration is abbreviate | omitted, in each of 1st and 2nd embodiment, it replaces with the anticorrosion tape 13, and adheres the soft tube which consists of a heat shrink synthetic resin tube etc. to the outer peripheral part of the connection apparatus 1. It is also a preferable aspect that the covering layer 6 is formed.

  In the second embodiment configured as described above, the support pressure reducing means configured as described above is connected to the PC steel material 4 in the subsequent work section B using the secondary side connection portion 3. 5 is attached in association with the terminal portions of the primary side connection portion 2 and the secondary side connection portion 3, and then the anticorrosion tape 13 is spirally wound to thereby form a connection portion structure having a restraining force relaxation function. Is done.

  Then, after the concrete laying in the succeeding work section B is finished, the PC steel material 4 in the succeeding work section B is tensioned, whereby the direct embedment connecting work of the PC steel material 4 is completed. At that time, the external force is applied to the connecting device 1 in the direction away from the bearing plate 8 due to the tension of the PC steel material 4 in the subsequent work section B, but the secondary container 10 having a variable volume due to compression is not filled in the connection device 1. Only the volume of the cured filler 12 corresponding to the amount of movement moves to the primary container 9 through the pipe 11. As a result, the restraining force relaxation function exhibited by the secondary side container 10 and the buffer function provided in the jacket layer 6 made of the anticorrosion tape 13 work together, so that the required amount of the connecting device 1 is not constrained by the concrete. Can only be moved.

Embodiments of the present invention will be described below with reference to the accompanying drawings.
FIG. 6 shows a diagram showing the transition state of the PC steel material tension of Comparative Example 1 using the connection structure shown in FIG. 4, and FIG. 7 uses the connection structure shown in FIG. The diagram showing the transition situation of the PC steel material tension of Comparative Example 2 was shown. FIG. 8 shows a diagram representing the transition state of the PC steel tension according to the embodiment of the method of the present invention. This diagram shows the connection according to the first embodiment of the present invention shown in FIG. This was obtained by conducting an experiment for confirming the effect of the present invention using a connection device having the same structure as the partial structure. Then, two examples (A-1, A-2) in Comparative Example 1 shown in FIG. 4 in which a space covering the entire connecting device is formed using the coupler sheath 14 and the connecting device is directly embedded in the concrete to restrain the binding force. Example 3 of the present invention (C-1, C-2) by giving three examples (B-1, B-2, B-3) in Comparative Example 2 shown in FIG. It was decided to compare the effects with.

  In the case of Comparative Example 1 (A-1, A-2), the fixing force of the preceding work section that had been acting on the bearing plate at the connection end decreased linearly as the tension of the subsequent work area increased. Was observed. In the case of Comparative Example 2 (B-1, B-2, B-3), even if the connecting device was restrained by concrete and the tension in the subsequent work area increased, the preceding work area that was acting on the bearing plate It was confirmed that the fixing power of the toner hardly changed.

  On the other hand, in the case of the present invention examples (C-1 and C-2) having a restraining force relaxation function, the coupler sheath 14 was used as an overall tendency although a slight loss of tension occurred. The property of tension transmission similar to that in Comparative Example 1 (A-1, A-2) was clearly observed, and this proved the excellent effect of the present invention.

It is a side view which shows the connection state which concerns on the 1st Embodiment of this invention. It is a side view which shows the connection state which concerns on the 2nd Embodiment of this invention. FIG. 3 is a perspective view of an element member of the support pressure relaxation means illustrated in FIG. It is explanatory drawing of the conventional direct embedment connection method of PC steel materials. It is explanatory drawing which shows the cross section of the attachment state of the conventional connection apparatus. It is a diagram showing the transition situation of PC steel materials tension of comparative example 1. It is a diagram showing the transition situation of PC steel materials tension of comparative example 2. It is a diagram showing the transition situation of PC steel materials tension concerning an embodiment of the method of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Connection apparatus 2 ... Primary side connection part 3 ... Secondary side connection part 4 ... PC steel material 5 ... Supporting pressure relaxation means 6 ... Outer coating layer 7 ... Solid board body 8 ... Supporting pressure plate 9 ... Primary side container 10 ... Two Next side container 11 ... Piping 12 ... Filling material 13 ... Anticorrosion tape 14 ... Shell pipe 15 ... Grouting material 16 ... Concrete A ... Preceding work zone B ... Subsequent work zone S ... Join surface

Claims (5)

  In the tension connection method of PC steel material, which connects the PC steel material by the direct embedding method using the connecting device having the primary side connection portion and the secondary side connection portion at the concrete joint portion of the preceding work zone and the subsequent work zone, In order to allow the connecting device to move against the restraining force caused by the concrete bearing pressure when tensioning the PC steel material in the working zone, a supporting pressure relaxation means is provided in association with the terminal portion of the secondary side connecting portion. In order to avoid the direct fixation between the connecting device and the concrete, a method for directly embedding and connecting PC steel, wherein an outer layer is attached to the outer peripheral portion of the connecting device.   A connecting part that is attached to a connecting device having a primary side connecting part and a secondary side connecting part for connecting PC steel under tension by a direct burying method at a concrete joint part in a preceding work area and a succeeding work area. The structure is made of a compressible solid board made of a soft material compared to concrete, and it is surrounded by PC steel in the subsequent work zone and attached to the terminal part of the secondary connection part. A connecting portion structure having a restraining force alleviating function, characterized in that it includes means and a covering layer formed on the outer peripheral portion of the connecting device.   Connection part structure attached to a connecting device having a primary side connection part and a secondary side connection part for connecting PC steel under tension by a direct burying method at the concrete joint part of the preceding and succeeding work areas A primary container placed between the terminal part of the primary side connecting part and the bearing plate, surrounded by the PC steel material of the preceding work area, formed in a volume-invariant hollow disk body, and a variable volume hollow disk body by compression A secondary container that is formed and surrounded by PC steel in the subsequent work zone and attached to the terminal part of the secondary connection part, a pipe that connects the primary and secondary containers together with the connection device, It is characterized in that it includes a support pressure relaxation means composed of each member of an uncured filler that is filled in the secondary container and hardens over time, and an outer cover layer that adheres to the outer periphery of the connection device. Connecting portion structure having a restraining force relaxation function.   The connecting portion having a restraining force relaxation function according to claim 2 or 3, wherein the covering layer is formed by spirally winding an anticorrosion tape made of a synthetic resin soft tape or the like around the outer peripheral portion of the connecting device. Construction.   The connection part structure provided with a restraining force relaxation function according to claim 2 or 3, wherein the covering layer is formed by attaching a soft tube made of a heat-shrinkable synthetic resin tube or the like to the outer peripheral part of the connection device.

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