JP2005090124A - Connecting structure for precast floor slab - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connecting structure for precast floor slabs which facilitates the tension control of a hollow PC steel bar and improves the fatigue resistance of the precast floor slab. <P>SOLUTION: In the connecting structure for connecting precast floor slabs 1, 3 to each other which are constructed over a cross beam 38 disposed in parallel to the other at an interval in a horizontal direction, holes 2, 4 or recessed parts are formed in both of the precast floor slabs 1, 3 to dispose a prestress introducing device 8. The prestress introducing device 8 includes the hollow PC steel bar 6 into which a pushing reaction PC steel bar 7 is pushed to strain the PC steel bar 6. The prestress introducing device 8 is disposed in each of the horizontal holes 2, 4 or the recessed parts of each of the precast floor slabs 1, 3. The holes 2, 4 or the recessed parts are filled with a filling material which is then hardened. A compressive force of the pushing reaction PC steel bar 7 is released and the compressive force is introduced by the hollow PC steel bar 6. Thus, the precast floor slabs 1, 3 adjacent to each other in a horizontal direction are connected in a state that the prestress is introduced in a direction to bring the floor slabs 1, 3 closer. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a connection structure between floor slabs in a bridge or an elevated road bridge, and more particularly to a connection structure between precast floor slabs.

  2. Description of the Related Art Conventionally, as a precast slab connection structure, a connection structure of a type that connects adjacent precast slabs in the bridge axis direction is known. (For example, refer to Patent Document 1 or Patent Document 2.)

  Since each of the above prior arts is a connection structure of the entire precast floor slabs adjacent to each other in the bridge axis direction, there is no disclosure of a connection structure between the split-type precast floor slabs divided into two in the direction perpendicular to the bridge axis. .

  Also, in the past, reinforced concrete floor slabs (RC floor slabs) in steel bridges deteriorated and replaced with precast PCa slabs (precast slabs). was there.

  When construction is performed with one lane open, as shown in FIGS. 16A to 16C, the existing RC floor slab 39 is divided into two at the center in the width direction, and the RC floor slab 39 on one side is removed, and then the part A new precast floor slab 14 is erected, and as shown in FIGS. 17A to 17C, after the other existing RC slab 39 is removed, a new precast slab 15 is erected. Since each precast floor slab 14 and 15 which opposes by the construction procedure is mounted on the girder 38, the vertical joint 16 of the upper longitudinal direction is made in the center of the width, and through the vertical joint gap in the lateral direction of the width. It is necessary to connect adjacent precast slabs 14 and 15.

For this reason, conventionally, a short PC steel bar 18 is used to connect the precast slabs 14 and 15 to each other.
JP-A-8-246415 JP-A-7-90814

  When the short PC steel bar 18 is used as described above, it is difficult to control the tension, and a high degree of skill is required. Further, as shown in FIG. The precast floor slabs 14 and 15 require notch recesses 46, and the precast floor slabs 14 and 15 require a large number of notch recesses 46. Therefore, the fatigue durability of the precast floor slabs 14 and 15 is further improved. It is hoped that

An object of the present invention is to provide a connection structure of a precast slab that can further improve the problem of difficult tension management by the short PC steel bar and the fatigue durability of the precast slab.

  In the connection structure of the precast floor slabs of the first invention, in the connection structure between the precast floor slabs 1 and 3 laid over the girders 38 arranged in parallel at intervals in the lateral direction, both precast floor slabs 1 , 3 are provided with lateral holes 2 and 4 for disposing the prestress introduction device 8, the lateral holes 2 and 4 are lateral holes opened on the connecting side surface, and the prestress introduction device 8 is a hollow PC steel. The hollow PC steel rod 6 that is tensioned by pushing the reaction force PC steel rod 7 for pushing into the inside of the rod 6 is provided, and extends into the horizontal holes 2 and 4 of the precast slabs 1 and 3, respectively. The prestress introduction device 8 is disposed and the filler is filled and hardened so as to embed the prestress introduction device 8, and the compressive force of the pushing reaction force PC steel rod 7 is released, so that the hollow PC steel rod 6 is released. The compression force is introduced by the lateral direction Wherein the precast slab 1, 3 adjacent are connected in a state where the direction prestress is introduced to approach.

  In the connection structure of the precast floor slabs of the second invention, in the connection structure between the precast floor slabs installed over the girders 38 arranged in parallel at intervals in the lateral direction, Are provided with recesses 11 and 13 for disposing the prestress introduction device 8, the recesses 11 and 13 are recesses opened in the connecting side surface, and the prestress introduction device 8 is disposed inside the hollow PC steel rod 6. The hollow PC steel rod 6 that has been tensioned by pushing the pushing reaction force PC steel rod 7 is provided, and the prestress introduction device 8 extends over the recesses 11 and 13 of the precast slabs 1 and 3. And the filler is filled and hardened so as to embed the prestress introduction device 8 and the compressive force of the pushing reaction force PC steel rod 7 is released and the compressive force is introduced by the hollow PC steel rod 6. Characterized in that the precast slab 1, 3 adjacent in the horizontal direction are connected in a state where the direction prestress is introduced to approach.

  In the third invention, in the precast floor slab connection structure according to the first invention, the entire length of the prestress introducing device 8 can be stored in one or both of the precast floor slabs 1 (3) facing in the lateral direction in the width direction. The precast floor slab 1 provided with a long horizontal hole 4 and opposed to the long horizontal hole 4 is provided with a short horizontal hole 2.

  In 4th invention, in the connection structure of the precast floor slab of 3rd invention, the long length which can accommodate the full length of the said prestress introduction apparatus 8 in the one or both precast floor slab 1 (3) which opposes a width direction. The precast floor slab 1 provided with a recess 13 and opposed to the long recess 13 is provided with a short recess 11.

In the fifth invention, in the connecting structure of the precast floor slabs of the second invention or the fourth invention, the recesses 11 and 13 are such that the upper floor slab reinforcement 12 is partially exposed at the recesses 11 and 13. It is characterized by the concave portions 11 and 13 having upward openings.

  According to the first invention or the second invention, since the prestress introduction device provided with the hollow PC steel rod is used, it is possible to use the prestress introduction device which has been tension-controlled accurately in advance in the factory. Since it is only necessary to open the PC steel bar for pushing, tension management at the site is almost unnecessary.

  Since a short PC steel bar is not used as in the prior art, it is not necessary to provide a notch recess having a vertical wall for supporting both ends of a short PC steel bar in each precast floor slab.

  By simply providing a hole or recess 3 for disposing the prestress introduction device 2 in the precast floor slab, it is possible to easily connect the precast floor slabs to each other and apply a predetermined prestress force and firmly connect them. Therefore, fatigue durability can be improved more reliably.

  Further, according to the first invention, since it is not necessary to provide a recess on the upper surface of at least one of the precast slabs, it is possible to effectively utilize the almost entire width of the upper surface of the one side of the precast slab. Can be used for.

  When a precast floor slab having a long horizontal hole is used, only the floor slab needs to be provided with a notch recess, so that the number of notch recesses can be halved compared to the conventional case. .

  According to the third or fourth aspect of the invention, the prestress introducing device including the pre-tensioned hollow PC steel bar is disposed in the long lateral hole or the concave portion of one or both precast slabs facing in the width direction. This makes it easy and easy to arrange the prestress introduction device. In addition, if both precast floor slabs are provided with long horizontal holes or recesses, the horizontal holes or recesses that accommodate the prestress introduction device can be alternately provided in the left and right floor slabs in the bridge axis direction. The long horizontal holes or the concave portions are not continuously arranged on one floor slab at intervals, and can be evenly arranged on the facing precast slab.

  Moreover, since only a notch recess is provided in the middle part of the long horizontal hole, the notch recess can be reduced as compared with the conventional case, and a notch recess for setting the release jig is provided. Even when it is provided on both of the precast slabs, it can be arranged uniformly without depending on one of the precast slabs. Moreover, since the front-end | tip part of a prestress introduction apparatus can be arrange | positioned to the back part of a short horizontal hole or a recessed part, the precast floor slab by the side of a short horizontal hole or a recessed part can be reinforced reliably.

According to the fifth aspect of the present invention, the hollow PC steel rod can be easily arranged, and can be reliably filled while confirming the filling of the non-shrink mortar, etc., and the integration of the precast floor slab and the grout can be performed on the upper side. The floor slab reinforcement can be used effectively and integrated reliably.

  Next, the present invention will be described in detail based on the illustrated embodiment.

  First, the structure of one form of the prestress introducing device 8 using reaction force PC steel used in the present invention will be described with reference to FIGS. 9 and 18.

  Fig.9 (a) shows the partially cutaway side view of 1 unit of the prestress introduction apparatus 8 for concrete using the hollow PC steel rod of one Embodiment used in this invention, (b) is the vertical side view. The hollow hollow steel steel rod body 6a has a male screw portion 20 outside one end (front end) in the longitudinal direction and a male screw portion 21 outside the other end (rear end). A female screw hole 22 at the front end of a bearing tube 25 having female screw holes 22 and 23 at both front and rear ends and a polygonal rotating tool engaging outer surface 24 is screwed to the male screw portion 21 of the PC steel rod 6. ing.

  A front male screw portion 27 of a stopper 26 made of a steel tubular annular locking piece is screwed into the female screw hole 23 at the rear end portion of the support tube 25, and a rotation is provided outside the rear end portion of the stopper 26. A moving tool engaging outer surface 28 is formed.

  The front end portion of the stopper 26 is disposed inside the support cylinder 25, and the rear end surface of the press locking piece 30 having the concave portion 29 is engaged with the front end portion, and the concave portion 29 of the front end portion of the press locking piece 30 is engaged. In the hollow PC steel rod 6, almost the whole other than the other end side is inserted and the other end side is arranged so as to protrude from the other end portion of the hollow PC steel rod 6. (Repulsive force PC steel rod for non-pull) 7 is fitted to the rear end portion.

  Note that the non-pull means a system that does not pull out, in other words, a stationary system.

  In this embodiment, the indentation steel bar 7 is constituted by a single indentation reaction force PC steel bar 7, but the other end side has a short removal reaction force PC steel bar and the indentation reaction force PC steel bar. The push-in reaction force PC steel rod 7 can be constituted by two pieces of the push-in reaction force PC steel rod slightly shorter than 7.

  An anchor member 32 made of a nut having a female screw portion 31 is detachably screwed to the male screw 20 outside the front end portion of the hollow PC steel rod 6, and the tip portion of the pushing reaction force PC steel rod 7 is the female screw. It is connected to the part 31. A male screw member 41 is screwed and fixed to the anchor member 32, and the distal end portion of the reaction force PC steel rod 7 is supported by the male screw member 41.

  In the state shown in FIG. 9, the prestress introducing device 8 is connected to the state shown in FIG. 18, the front frame 43 and the rear frame 44 are coupled in parallel by a plurality of connecting rods 45, and the hydraulic jack 34 is connected to the rear frame 44 side. Is placed on a frame-shaped frame 33 provided with a hydraulic jack 34 and is engaged with the distal end portion of the movable piston 35 by means of a push-in steel rod 36 inserted into the central hollow portion of the stopper 26. After pressing the stop 30 so as to move toward the hollow PC steel rod 6 and introducing a compressive force so as to push the pushing reaction force PC steel rod 7 into the hollow PC steel rod 6, in that state The free support cylinder 25 or the stopper 26 is rotated in the direction approaching the pressing locking piece 30 (the right direction in FIG. 9), and the stopper 26 is moved forward to stop the stopper 6 the front end is engaged with the push retaining pieces 30 of a diagram showing a state of being separated from the frame-shaped frame 33.

  Such a prestress introduction device 8 is known from Japanese Patent Application Laid-Open No. 2001-207590 and the like, and various types of devices including a pushing reaction force PC steel rod and a hollow PC steel rod can also be used.

  Next, the structure form of 1st Embodiment of the precast slab used in this invention is demonstrated with reference to FIG. 1 and FIG.

  After the existing RC floor slab 39 on one side in the width direction is removed from the center of the width direction central girder 38, the pre-stress is introduced as the precast floor slab 1 that is erected over the plurality of girders 38 on one side in advance. A short lateral hole 2 that is shorter than the length of the device 8 (in the illustrated form, approximately half the length of the prestress introduction device 8) and that can accommodate a part of the prestress introduction device 8 is formed in the thickness direction. A precast floor slab 1 provided on the upper side is used. The illustrated precast floor slab 1 is a precast PC floor slab to which prestress is applied by an embedded and fixed PC steel not shown.

  The short horizontal hole 2 is a horizontal hole that opens in the inner end surface on the center side in the width direction (road width direction, etc.) in the precast floor slab 1, and a plurality of the short horizontal holes 2 are provided at intervals in the bridge axis direction. In addition, a grout hole 2a that opens in the upper surface of the floor slab is provided on the back side of each horizontal hole 2.

  As the precast floor slab 2 to be installed after the existing RC floor slab 39 on the other side in the width direction is removed, the length of the prestress introduction device 8 is equal to or longer than the length of the prestress introduction device 8. A precast floor slab 3 that can accommodate almost the entire length and has a long horizontal hole 4 on the upper end side in the thickness direction that is opened in an inner end face that is a central side that is a joining end face side is used.

  The following precast floor slab 3 communicates with the lateral hole 4 in the middle portion in the longitudinal direction of the lateral hole 4 and is slightly deeper than the lower end level of the lateral hole 4 and opens on the upper surface of the floor slab. A notch recess 5 is provided.

  Therefore, the long horizontal hole 4 is constituted by the cutout recess 5 and the horizontal holes 4 a and 4 b on both sides in the width direction of the cutout recess 5.

  Further, the lateral hole 4b on the back side of the long lateral hole 4 is provided with a grout hole 4c opened in the upper surface of the floor slab, and a position close to the notch recess 5 on the width center side. In addition, a grout hole 4c is provided which communicates with the lateral hole 4a on the width center side and opens on the upper surface of the floor slab.

  The long horizontal hole 4 and the notch recess 5 are provided in parallel with a gap in the bridge axis direction.

  A prestress introduction device 8 is inserted into the long horizontal holes 4 in the precast floor slab 3 having the long horizontal holes 4 as described above from the inner end face side on the width center side, The prestress introduction device 8 is stored and arranged in advance, for example, immediately before the precast floor slab 3 is installed so that the stopper 26 side is located in the back of the horizontal hole 4 (4b), and the temporary holding jig is provided in the notch recess 5 as necessary. In a state of being temporarily held and appropriately disposed, the precast floor slab 1 previously erected is erected on the girder 38 through the gap of the vertical joint 16.

  The preceding or succeeding precast floor slabs 1 and 3 installed between a plurality of girders 38 are constructed with appropriate adjustment mortars on each girder 38.

  A gibber such as a stud gibber is appropriately provided on the beam 38 at the center of the joint gap, but the illustration is omitted.

  Next, the precast floor slab connection structure of the present invention using the prestress introduction device 8 described above, the construction procedure shown in FIGS. 1 to 7 and the precast of the completed first embodiment of the present invention shown in FIG. The connecting structure of the floor slab will be described with reference to the order.

  FIGS. 1 and 2 show a state in which the existing RC floor slab 39 is removed and new precast floor slabs 1 and 3 installed in the preceding and succeeding stages are installed as shown in FIGS. 16 and 17. is there.

  From the state of FIG. 1 and FIG. 2, as shown in FIGS. 3 (a) and 3 (b), the operator holds the prestress introduction device 8 at the portion located in the notch recess 5 in the precast floor slab 3. It is drawn out and placed in the lateral hole of the other precast floor slab 1 facing it.

  Next, as shown in FIG. 4 and FIG. 5, the short and long horizontal holes 2, 4 of the opposing precast floor slabs 1, 3 communicate with the vertical joint between the precast floor slabs 1, 3. In a state where a split-type cylindrical mold (not shown) is arranged, a filler made of grout such as non-shrink mortar is filled.

  Further, from the short horizontal hole 2 in the preceding precast floor slab 1 or from the grout hole 4c on the center side in the subsequent precast floor slab 4, a filler composed of a grout 17 such as a non-shrink mortar is used as a short horizontal hole. From 2 to the end surface of the notch recess 5 on the width central portion side, the filling is performed, and the anchor material 37 screwed into the male screw portion 21 in the prestress introduction device 8 is embedded from the tip portion of the prestress introduction device 8. In addition, a mold (not shown) is disposed on the notched recess 5 side as appropriate.

  After the filler made of the grout 17 is cured and exhibits a predetermined strength (after the adhesion to the prestress introduction device 8 is sufficient), as shown in FIG. A release jig 9 having a gear mechanism having an output shaft 10 formed of a cylindrical gear having a polygonal inner engagement portion that can be fitted to the stopper 26 at one end of the device 8 is set.

  Further, the stopper 26 is retracted by fitting an output shaft of an electric or manual rotating tool to an input shaft 10a formed of a cylindrical gear having a polygonal inner engagement portion in the release jig 9. Thus, the compressive force of the indentation reaction force PC steel bar 7 is released, and conversely, the adhesion between the hollow PC steel bar 6 and the grout 17 and the adhesion between the grout 17 and each precast slab 1, 3 The shortening of the hollow PC steel bar 6 is prevented, whereby a prestress of compression is introduced in a direction in which the precast floor slabs 1 and 3 are relatively approached, and are firmly joined and integrated.

  If the adhesion between the hollow PC steel rod 6 and the filler composed of the grout 17 is sufficient, the anchor material 32 and the anchor member 37 can be omitted in principle.

  The stopper 26 and the support cylinder 25 can be removed, and the pushing reaction force PC steel rod 7 can be removed. However, as shown in FIG. 7, the pushing reaction force PC steel rod 7 is left to remain. The reaction force PC steel rod 7 can also be used.

  When the pushing reaction force PC steel rod 7 is left behind, the support cylinder 25 is removed from the hollow PC steel rod 6 and hardened after the filler made of the grout 17 is cured, so that the hollow PC steel rod 6 and the pushing reaction force PC are cured. In order to improve the integrity of the steel bar 7 and improve the ultimate strength of the bonded precast floor slabs 1 and 3, it is composed of a time-curing type synthetic resin adhesive appropriately mixed with a curable adhesive. The adhesive / rust preventive material 40 is injected and filled in advance or at an appropriate time from the end opening of the hollow PC steel rod 6.

  Then, after removing the support cylinder 25, without recovering the pushing reaction force PC steel rod 7, it is left in the hollow PC steel rod 6 and is used as an anticorrosive material such as a time-cured resin that also serves as an antirust. Integration of the hollow PC steel rod 6 and the pushing PC steel rod 7 is achieved by curing 40.

  Thereafter, as shown in FIG. 8, the grout 17 is filled from the grout hole 4 c into the lateral hole 4 b on the back side of the long transverse hole 4 not filled with the grout 17, and the notch recess 5 is not filled. The grout 17 such as shrink mortar is filled to prevent the hollow PC steel bar 6 and the reaction force PC steel bar 7 from being rusted, and the connection between the precast floor slabs 1 and 3 is completed.

  In this 1st Embodiment, since there is no recessed part in the upper surface of the precast floor slab 1, the full width in the floor slab width direction can be used effectively for traffic and the like.

(Modification of the first embodiment)
10 (a) and 10 (b) illustrate a precast floor slab 1 and a precast floor slab 3 that follow, a long horizontal hole 4 having a notch recess 5 in an intermediate portion, and a short horizontal hole 2 Using precast floor slabs 1 and 3 provided alternately in parallel in the longitudinal direction of the bridge axis, and the long horizontal holes 4 and short lengths of the prestressed concrete slabs 1 and 3 facing in the width direction. It is the form which arrange | positions so that the horizontal hole 2 may be opposed, and arrange | positions the notch recessed part 5 in zigzag form in a bridge axis direction.

  When the notch recesses 5 are alternately arranged in a staggered manner in this way, the cross-sectional defects due to the notch recesses 5 are not concentrated on one prestressed concrete floor slab, and are provided in a straight line in the bridge axis direction at short intervals. Therefore, the long horizontal holes 4 and the short horizontal holes 2 can be arranged relatively densely.

(Second Embodiment)
FIGS. 11-14 shows the state in the middle of construction of the connection structure of the precast floor slab of 2nd Embodiment in this invention, FIG. 15 has shown the state which completed the connection.

  As the precast floor slab 1 constructed in advance over a plurality of girders 38 on one side after the existing RC floor slab 39 on one side in the width direction is removed from the center of the girder 38 in the center in the width direction, this second embodiment is performed. The prestressed concrete floor slab 1 used in the form is shorter than the length of the prestress introduction device 8 and can accommodate a part of the prestress introduction device 8 in the upper side and the center side in the width direction (road width direction, etc.) A recess 11 having a short width direction dimension (substantially half the length of the pre-stress introduction device 8) provided in the inner end face (joint end face), which is provided on the upper side in the thickness direction, and in the recess 11 A prestressed concrete floor slab 1 is used which is a recess 11 in a state in which the floor slab reinforcing bar 12 that is spaced at the upper side is exposed.

  A plurality of the short recesses 11 are provided in parallel with a gap in the bridge axis direction, and the grout 17 from the floor slab upper surface side is facilitated, and the prestress introduction device 8 is attached to the floor slab reinforcing bar 12 by a wire or the like. By holding it, the arrangement of the prestress introduction device 8 can be reliably held at the central position without being inclined.

  Subsequently, after the existing RC floor slab 39 on the other side in the width direction is removed from the center portion of the width direction center girder 38, the length of the prestress introducing device 8 is the same as that of the precast floor slab 3 that is installed afterward. It is somewhat longer than this, opens to the upper end and the inner end surface (joint end surface) which is the center side in the width direction (road width direction, etc.), can store almost the entire length of the prestress introduction device 8, and A precast floor slab 3 is used in which a long upward opening recess 13 is provided on the upper side in the thickness direction in a state where the floor slab reinforcing bars 12 that are spaced apart on the upper side are exposed.

  The long concave portion 13 is provided in parallel with a gap in the bridge axis direction so that the grout 17 from the upper surface side of the floor slab is easy to be a precast floor slab 3. By holding the floor slab reinforcing bar 12, it can be temporarily held without being inclined, and the prestress introduction device 8 can be securely held at the center position without being inclined.

  In FIG. 11, the prestress introduction device 8 is provided in each of the long recesses 13 in the precast floor slab 3 having the long recesses 13 as described above. In addition to being inserted through the opening, the prestress floor 8 was preliminarily stored and arranged in the yard near the factory or the site so that the stopper 26 side of the prestress introduction device 8 is located in the back of the recess 13. In the state, a state is shown in which the plurality of girders 38 are installed on the preceding precast floor slab 1 through joint gaps.

  From this state, as shown in FIGS. 12A and 12B, the prestress introduction device 8 in the long concave portion 13 in the precast floor slab 3 is grasped by an operator and the other precast floor slab 1 is opposed. It is drawn out to the inner part of the recess 11 and is held so as to be positioned on the central axis of each recess 11 and 13 by a suitable number line or the like.

  Next, as shown in FIGS. 13 (a) and 13 (b), in the vertical joint between the precast floor slabs 1 and 3, and in the short and long recesses 11 and 13 between the opposing precast floor slabs 1 and 3, respectively. A grout 17 such as a non-shrink mortar is filled so as to embed from the tip of the prestress introducing device 8 to the anchor material 37. A formwork (not shown) is appropriately disposed outside the anchor material 37.

  After the grout 17 is cured and exhibits a predetermined strength (after the adhesion to the prestress introduction device 8 is sufficient), as shown in FIGS. The release jig 9 is set on the stopper 26 at one end of the prestress introduction device 8 as in the above embodiment. When the prestress introduction device 8 is arranged so that the stopper 26 in the prestress introduction device 8 is in a position protruding from the floor slab rebar 12 so that the opening jig 9 can be set between the floor slab rebars. desirable.

  Then, as in the above embodiment, the compression force of the pushing reaction force PC steel rod 7 is released by rotating the stopper 26 so as to move backward, and conversely, the hollow PC steel rod 6 and the grout 17 Adhesion and adhesion between the grout 17 and the precast floor slabs 1 and 3 prevent the hollow PC steel bar 6 from being shortened, thereby introducing a prestress of compression in a direction in which the precast floor slabs 1 and 3 approach each other relatively. Are firmly joined and integrated.

  The stopper 26 and the support cylinder 25 are removed, and the remaining recess 13 is filled with a grout 17 such as a non-shrink mortar as shown in FIG. Connect each other firmly.

  In the illustrated embodiment, a form in which the precast floor slabs 1 and 3 are installed between the two girders 38 among the three girders 38 spaced in the lateral direction is shown. In this case, the precast floor slab 1 (3) may be installed over three or more girders 38.

The connection structure of the precast floor slab of 1st Embodiment in this invention shows the state in the middle of construction, Comprising: (a) arrange | positions a prestress introduction apparatus in a recessed part so as to oppose the horizontal direction of a width direction. The schematic plan view which shows the state which mounted the precast floor slab and the precast floor slab which have a recessed part on the girder, (b) is a front view. (A) is a top view which expands and shows a part of Fig.1 (a), (b) is a longitudinal front view which shows the arrangement | positioning state of the prestress introduction apparatus in a recessed part. FIG. 2A is a plan view showing a state in which the prestress introduction device is pulled out from the state of FIG. 2A to the back of the recessed part of the other precast floor slab, and FIG. 2B is a prestress introduction in the recessed part. It is a vertical front view which shows the arrangement | positioning state of an apparatus. (A) is a top view which shows the state which filled the grout in the recessed part of both the precast floor slabs except the joint part and the recessed part of the one end part side of a prestress introduction apparatus from the state of Fig.3 (a), (b) ) Is a longitudinal front view thereof. It is a longitudinal front view which expands and shows FIG.4 (b). (A) is a top view which shows the state which set the release jig to the one end part of the prestress introduction apparatus of the state of Fig.4 (a), (b) is the longitudinal cross-sectional front view. It is a longitudinal front view which expands and shows FIG.6 (b). It is a longitudinal front view which shows the state which filled the grout into the recessed part which is not filled with grout, and completed the connection of the precast slabs. BRIEF DESCRIPTION OF THE DRAWINGS It shows one form of the prestress introduction apparatus used in this invention, Comprising: (a) is a partially notched side view, (b) is a partially notched longitudinal side view. 1 shows a form in which notched recesses are alternately arranged in a staggered pattern on opposing precast floor slabs, and (a) shows a prestress introduction device arranged in the recess so as to face in the lateral direction in the width direction. The schematic plan view which shows the state which mounted the precast floor slab and the precast floor slab which has a recessed part on the girder, (b) is a front view. The connection structure of the precast floor slab of 2nd Embodiment in this invention shows the state in the middle of construction, Comprising: (a) arrange | positions a prestress introduction apparatus in a recessed part so as to oppose the width direction horizontal direction. The schematic plan view which shows the state which mounted the precast floor slab and the precast floor slab which have a recessed part on the girder, (b) is a front view. FIG. 12A is a plan view showing a state in which the prestress introduction device is pulled out from the state of FIG. 12A to the back of the recessed part of the other precast floor slab, and FIG. 12B is a prestress introduction in the recessed part. It is a vertical front view which shows the arrangement | positioning state of an apparatus. (A) is a top view which shows the state which filled the grout in the recessed part of both the precast floor slabs except the joint part and the recessed part of the one end part side of a prestress introduction apparatus from the state of Fig.12 (a), (b) ) Is a longitudinal front view thereof. (A) is a top view which shows the state which set the release jig to the one end part of the prestress introduction apparatus of the state of Fig.15 (a), (b) is the longitudinal cross-sectional front view. (A) is a top view which shows the state which filled the grout to the recessed part which is not filled with grout, and completed the connection of the precast floor slab, (b) is a longitudinal front view. (A)-(c) is a schematic longitudinal front view which shows the construction procedure by a precast floor slab. (A)-(c) is a schematic longitudinal front view which shows the construction procedure by a precast floor slab. It is a vertical side view which shows one form in the case of setting a prestress introduction apparatus to the frame-shaped frame provided with the hydraulic jack, and introducing tension | tensile_strength to a hollow PC steel rod. The connection structure of the precast floor slab using the conventional PC steel bar is shown, Comprising: (a) is a top view, (b) is a vertical front view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Precast floor slab preliminarily installed 2 Short horizontal hole 3 Precast floor slab 4 installed backwardly Long horizontal hole 4a Horizontal hole 4b Horizontal hole 5 Notch recessed part 6 Hollow PC steel rod 6a Hollow PC Steel bar body 7 Pushing reaction force PC steel bar 8 Prestress introduction device 9 Release jig 10 Output shaft 11 Recess 12 Floor slab 13 Long recess 14 New precast floor slab 15 New precast slab 16 Longitudinal joint 17 Grout 18 Short PC Steel Bar 20 Male Threaded Part 21 Male Threaded Part 22 Female Threaded Hole 23 Female Threaded Hole 24 Rotating Tool Engaging Outer Surface 25 Bearing Cylinder 26 Stopper 27 Front Male Threaded Part 28 Rotating Tool Engaging Outer Surface 29 Concave 30 Press Locking Piece 31 Female thread portion 32 Anchor material 33 Frame-shaped frame 34 Hydraulic jack 35 Movable piston 36 Push-in steel rod 37 Anchor material 38 Girder 39 Existing RC floor slab 40 Bonding and prevention Material 41 male screw member 43 the front frame 44 rear frame 45 connecting rod 46 notched recess

Claims (5)

  In the connection structure between the precast floor slabs that are installed across the girders that are arranged in parallel at intervals in the lateral direction, a lateral hole for arranging the prestress introducing device is provided in both precast floor slabs, The horizontal hole is a horizontal hole that opens in the connecting side surface, and the prestress introduction device includes the hollow PC steel rod that is tensioned by pushing the reaction force PC steel rod into the hollow PC steel rod. In addition, a prestress introduction device is disposed in each side hole of each precast floor slab, and a filler is filled and hardened so as to embed the prestress introduction device, and the reaction force PC steel rod for pushing is compressed. It is characterized in that the force is released and a compressive force is introduced by the hollow PC steel bar, and the precast slabs adjacent in the lateral direction are connected in a state where prestress is introduced in the approaching direction. Consolidated structure of precast floor slab.   In the interconnecting structure of precast floor slabs laid across girders arranged in parallel at intervals in the lateral direction, a recess for arranging a prestress introducing device is provided on both precast floor slabs, the recess Is a recess opened in the connecting side surface, and the prestress introduction device includes the hollow PC steel rod that is tensioned by pushing the pushing reaction force PC steel rod into the inside of the hollow PC steel rod, A prestress introduction device is arranged in each recess of each precast floor slab, and the filler is filled and hardened so as to embed the prestress introduction device, and the compression force of the pushing reaction force PC steel bar is released. The compression force is introduced by the hollow PC steel rod, and the precast slabs adjacent in the lateral direction are connected in a state where prestress is introduced in the approaching direction. Consolidated structure of precast floor slab.   One or both precast floor slabs facing in the lateral direction of the width direction are provided with long lateral holes capable of accommodating the entire length of the prestress introducing device, and the precast floor slab facing the long lateral holes The connecting structure for a precast floor slab according to claim 1, wherein a short horizontal hole is provided.   One or both of the precast floor slabs facing in the width direction are provided with a long concave portion capable of accommodating the entire length of the prestress introducing device, and the precast floor slab facing the long concave portion has a short length. The connecting structure for a precast slab according to claim 2, wherein a recess is provided.   The connection of the precast floor slab according to claim 2 or 4, wherein the concave portion is a concave portion having an upward opening in which the upper part of the floor slab reinforcement is partially exposed at the portion of the concave portion. Construction.

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