JP7169152B2 - Joint structure of precast concrete members - Google Patents

Description

The present invention relates to joint structures for precast concrete members.

BACKGROUND ART Conventionally, precast concrete members (PC members) such as composite floor slabs (steel/concrete composite floor slabs) formed by integrally forming steel plates and concrete, for example, are known as floor slabs for road bridges and railway bridges. For such a PC member joint structure, a joining method using a loop joint structure as shown in Patent Documents 1 and 2, or a lap joint structure by mechanical fixation as shown in Patent Document 3, has been proposed. It is especially applied to floor slab renewal work.

In Patent Document 1, loop joints protruding from respective joint surfaces of two PC members to be joined are alternately arranged in a direction (member width direction) orthogonal to the joining direction in plan view. A possible loop joint structure is described.
In Patent Document 2, loop joints projecting from the joint surfaces of two PC members to be joined are arranged line-symmetrically with respect to the joint surfaces, and an annular loop muscle is formed between the loop joints in the member width direction. An arranged joint structure is disclosed.
Patent Document 3 describes a joint structure in which mechanical fixing portions protruding from joint surfaces of two PC members to be joined are alternately shifted in the member width direction.

JP 2012-26088 A JP-A-2002-227130 JP 2015-229818 A

However, conventional joint structures for precast concrete members (PC members) have the following problems.
That is, the above-mentioned Patent Documents 1 and 3 have a configuration in which the respective joints are arranged asymmetrically with respect to the joining end surfaces of the two PC members, and the joints are positioned in the member width direction so as not to interfere with each other. It should be staggered. Therefore, in the case of members such as beams that are narrower than the floor slabs, twisting behavior may occur at joints, and there is room for improvement in this respect.

Moreover, in the case of the loop joints disclosed in Patent Documents 1 and 2, the thickness of the PC member cannot be reduced because the bending inner radius of the loop joint is limited. Furthermore, there is a problem that it requires labor and time to insert a reinforcing reinforcing bar inside the loop reinforcing bar, which increases the cost.

In Patent Document 2, by adopting a configuration that uses an annular loop muscle separate from the loop joint, it is possible to arrange it line-symmetrically with respect to the joint end surface, but with respect to the loop joint on the side of each PC member Loop muscles should overlap. As a result, there are two overlapped portions, and the dimension between the joint end faces in the interstitial portion becomes large, resulting in an increase in the volume of concrete and an increase in cost.

Further, in Patent Document 3, in the case of a joint by mechanical fixation, the thickness of the member can be reduced, but in general, the lap joint length of this joining method needs to be about 15 times (15D) the diameter D of the joint reinforcing bar. Therefore, there is a problem that the dimension between the joint end faces in the interstitial portion becomes large, the volume of concrete increases, the work takes time and labor, and the cost increases.

The present invention has been made in view of the above-mentioned problems, and can reduce the labor and time required for construction, and furthermore, it is possible to reduce the distance between the joint end faces, and it is possible to reduce the cost. It is an object of the present invention to provide a joint structure for precast concrete members.
Another object of the present invention is to provide a joint structure for precast concrete members that can prevent twisting of the precast concrete members even when the number of joint reinforcing bars is small.

In order to achieve the above object, the joint structure of precast concrete members according to the present invention is a joint structure of precast concrete members for joining precast concrete members formed by integrally molding a reinforcing bar and concrete, the joint structure comprising: a front end portion; a joint reinforcing bar having a widened portion in the precast concrete member and having a mechanical fixing portion arranged so as to protrude from the joint end face of the precast concrete member on the side of the widened portion; Filling concrete filled in the filling region between the joint end faces of the precast concrete members, and widening portions at both ends, and the filling region is arranged with its axial direction parallel to the axial direction of the joint reinforcing bar. the mechanical anchoring portions of the precast concrete members to be joined are arranged on a coaxial line, and the joining reinforcing bars extend between the mechanical anchoring portions in the width direction of the precast concrete member. In the interstitial space in which the interspaced space is filled with the interspace concrete, the mechanical fixing portion and the joining reinforcing bar are provided at the same height in the thickness direction of the interspace space. and is connected to at least one of the upper side and the lower side of the mechanical anchoring portion and the joining reinforcing bar, and is provided with a reinforcing reinforcing bar extending in a direction intersecting the mechanical anchoring portion and the joining reinforcing bar . It is characterized by

In the present invention, the mechanical fixing portions of the joint reinforcing bars of adjacent precast concrete members are arranged on the same axis, and the joint reinforcing bars are arranged between the joint reinforcing bars in the width direction of the precast concrete members. The length of the mechanical fixing section can be shortened. In this case, there is no need to displace the reinforcing bar joints in the width direction in order to prevent interference between the reinforcing bar joints as in the conventional art. can be done. Therefore, it is possible to reduce the filling amount of the interstitial concrete filled in the interstitial area, and it is possible to reduce the cost.

In addition, when arranging the joint reinforcing bars in the interstitial area, the joint reinforcing bars can be arranged by a simple work of inserting the joint reinforcing bars from above between the mechanical fixing portions arranged in the width direction. Therefore, it is not necessary to insert a reinforcing reinforcing bar into the loop of the loop reinforcing bar as in the conventional art, and the labor and time required for construction can be reduced.
Further, according to the present invention, twisting between precast concrete members can be prevented even in the case of a member having a small number of joint reinforcing bars or in the case of displacing both reinforcing bars in the width direction.

As described above, the present invention can be applied to joining various precast concrete members regardless of wide members such as floor slabs. The member thickness can be reduced. Therefore, it is possible to reduce the labor and time required for on-site joining, and to reduce the cost of the joint structure.

Further, in the joint structure for precast concrete members according to the present invention, in the interstitial portion in which the interstitial area is filled with the interstitial concrete, the mechanical fixing portion and the joining reinforcing bar have a thickness of the interstitial portion provided at the same height in the same direction, connected to at least one of the upper side and the lower side of the mechanical anchoring portion and the joining reinforcing bar, and extending in a direction intersecting the mechanical anchoring portion and the joining reinforcing bar. It may be characterized by the provision of existing reinforcing bars.

In this case, since the reinforcing reinforcing bars extend in a direction intersecting the joint reinforcing bars and the joining reinforcing bars, the reinforcing reinforcing bars are locked to the widened portion to restrict the axial movement of the joint reinforcing bars and the joining reinforcing bars. be able to. In other words, by providing the reinforcing reinforcing bars, it is possible to restrain the joint reinforcing bars and the joining reinforcing bars from slipping out or bending due to axial movement.
In addition, in the present invention, since the joint reinforcing bars can be arranged at the same height as the joint reinforcing bars in the thickness direction of the interstitial portion, the thickness of the interstitial portion can be kept small.
Moreover, in the construction of the reinforcing bars, it is only necessary to add the reinforcing bars so as to sandwich the mechanical fixing part and the joining reinforcing bars from above and below, and there is an advantage that no special jig is required.

Further, in the joint structure of precast concrete members according to the present invention, a bottom steel plate projecting from the joint end face is integrally provided on the bottom surface of the concrete of the precast concrete member, and the bottom of the adjacent precast concrete members is provided. The splicing plate may be provided so as to bridge the projecting portions of the steel plates, and a high-strength bolt for joining the splicing plate and the bottom steel plate.

In this case, even if it is a composite member with a bottom steel plate provided on the bottom surface of concrete, by joining the protruding part of the bottom steel plate and the splice plate at the interposed part with high-strength bolts, it is possible to make it strong and easy. can be fixed.

Further, in the joint structure for precast concrete members according to the present invention, the plurality of mechanical fixing portions are provided so as to be engageable from above, and a reinforcing plate is provided for connecting the plurality of mechanical fixing portions. It may be characterized by

In this case, since the reinforcing plate extends in the direction intersecting the joint reinforcing bars and the joining reinforcing bars, the reinforcing plate is engaged with the widened portion, and the axial direction of the joint reinforcing bars and the joining reinforcing bars is prevented. movement can be regulated. That is, by providing the reinforcing plate, it is possible to restrain the pull-out and bending due to the axial movement of the joint reinforcing bars and the joining reinforcing bars.
Moreover, the work of engaging the reinforcing plate with the mechanical fixing portion or the joining reinforcing bar from above is simple, and there is the advantage that no special jig is required.

According to the joint structure of the precast concrete members of the present invention, it is possible to reduce the labor and time required for construction, and it is possible to reduce the distance between the joint end faces, thereby reducing the cost.
Moreover, according to the joint structure of the precast concrete members of the present invention, it is possible to prevent twisting of the precast concrete members even when the number of joint reinforcing bars is small.

FIG. 2 is a plan view showing the joint structure of the composite floor slab according to the first embodiment of the present invention, showing a state before concrete is placed in the interstitial area. Fig. 2 is a vertical cross-sectional view of the joint structure shown in Fig. 1 in which concrete is placed in the filling region, where (a) is a cross-sectional view taken along line AA in Fig. 1, and (b) is line BB in Fig. 1; It is a sectional view. FIG. 2 is a cross-sectional view taken along the line CC shown in FIG. 1, and is a vertical cross-sectional view of the joint structure in which concrete is placed in the filling region. It is an exploded view of the joint structure shown in FIG.2(a), (b). [ Fig. 10] Fig. 10 is a plan view showing the joint structure of precast concrete members according to the second embodiment, showing a state before concrete is placed in the interstitial area. FIG. 6 is a cross-sectional view taken along the line DD shown in FIG. 5, and is a vertical cross-sectional view showing a state in which concrete is placed in the filling region in the joint structure. [ Fig. 10] Fig. 10 is a plan view showing the joint structure of the composite floor slab according to the third embodiment, showing a state before concrete is placed in the interstitial area. FIG. 8 is a cross-sectional view taken along the line EE shown in FIG. 7, and is a vertical cross-sectional view of the joint structure in which concrete is placed in the filling region. FIG. 8 is a cross-sectional view taken along line FF shown in FIG. 7;

BEST MODE FOR CARRYING OUT THE INVENTION A joint structure for precast concrete members according to an embodiment of the present invention will be described below with reference to the drawings.

(First embodiment)
As shown in FIGS. 1 to 3, the joint portion 2 (joint structure) of the precast concrete member according to the present embodiment (simply referred to as "composite floor slab 1 (1A, 1B)" in the following description) is used for road bridges and It is applied to precast composite floor slabs of railway bridges. The composite floor slabs 1A and 1B are constructed in advance at a factory by using a bottom steel plate 13 as a formwork, placing and filling concrete 14 above (inside) the bottom steel plate 13, and molding the bottom steel plate 13 and the concrete 14 integrally.

The joint portion 2 is a joint structure for joining the joint end surfaces 1a, 1a of the adjacent composite floor slabs 1A, 1B at the construction site.
Here, in the composite floor slab 1 and the joint portion 2, the direction in which the composite floor slabs 1A and 1B are joined is referred to as the joining direction X1, and the direction orthogonal to the joining direction X1 in plan view is referred to as the width direction X2.

In the composite floor slabs 1A and 1B of the present embodiment, a joint reinforcing bar 10 having a widened portion 10a at the tip is used as a compressed reinforcing bar. A mechanical fixing portion 10A is formed so as to protrude outward from the joint end surfaces 1a, 1a.

The joint portion 2 of the composite floor slabs 1A, 1B is arranged in the interstitial area 20 with a predetermined gap between the joint end surfaces 1a, 1a of the adjacent composite floor slabs 1A, 1B.
The joint portion 2 is a gap between the joint end surfaces 1a, 1a of the mechanical fixing portion 10A of the joint reinforcing bar 10 described above and the joint end surfaces 1a, 1a of the composite floor slabs 1A, 1B that are joined to each other so as to embed the mechanical fixing portion 10A. The interstitial concrete 4 filled in the area 20, and the joint reinforcing bars having the widened portions 3a at both ends and arranged in the interstitial area 20 so that the axial direction is parallel to the axial direction of the joint reinforcing bars 10 (that is, the joint direction X1). 3 and .

The joint reinforcing bars 10 provided on the composite floor slabs 1A and 1B are arranged so that the mechanical fixing portions 10A protruding from the joint end surfaces 1a and 1a face each other with a gap on the coaxial line.
In the concrete 14 of the composite floor slabs 1A, 1B, a plurality of bar arrangements 15, 15, . .

A bottom steel plate 13 protruding from the joint end surfaces 1a, 1a is integrally provided on the bottom surface of the concrete 14 of the composite floor slabs 1A, 1B. A projecting portion (overhanging piece portion 13a) of the bottom steel plate 13 is formed with a bolt hole (not shown) through which a high-strength bolt 24, which will be described later, is inserted.
That is, the joint portion 2 is arranged so that the mechanical fixing portions 10A, 10A of the joint reinforcing bars 10 of the composite floor slabs 1A, 1B to be joined are coaxially aligned in the joining direction X1, and the adjacent composite floor slabs 1A, 1B are arranged on the same axis. The overhanging pieces 13a, 13a of the bottom steel plate 13 of 1B are joined together using a splicing plate 21, a nut 22, a washer 23, and a high-strength bolt 24. The splicing plate 21 is arranged so as to bridge overhanging pieces 13 a of the bottom steel plate 13 .

The joining reinforcing bar 3 is arranged between the mechanical fixing portions 10A, 10A in the width direction X2. The joint reinforcing bar 3 has a length dimension shorter than the interval between the joint end surfaces 1a, 1a, and has widened portions 3a having the same shape as the widened portions 10a of the joint reinforcing bar 10 at both ends. The mechanical fixing part 10A and the joining reinforcing bar 3 are provided at the same height position in the thickness direction in the interstitial part 20A in which the interstitial space 20 is filled with the interstitial concrete 4 .

A plurality of reinforcing reinforcing bars 5, 5, . . The reinforcing bars 5 are arranged in a joining direction X1 that intersects the mechanical fixing part 10A and the joining reinforcing bars 3 above and below the mechanical fixing part 10A and the joining reinforcing bars 3, respectively, with the axial direction oriented in the width direction X2. A plurality (four) are arranged along the .

Here, in this embodiment, as the joint reinforcing bar 10 having the widened portion 10a and the joint reinforcing bar 3 having the widened portion 3a, the widened portions 10a and 3a are formed in a T-shaped T-head construction method (registered trademark, Shimizu Corporation). ) is used. As the joint reinforcing bars 10 and the joining reinforcing bars 3, reinforcing bars other than the above T-head construction method reinforcing bars can be used.
As the filling concrete 4, concrete or mortar having compressive strength equal to or greater than that of the synthetic floor slabs 1A and 1B is used.

As a construction method for the composite floor slab 1 (1A, 1B) configured in this way, first, as shown in FIG. The synthetic floor slabs 1A and 1B integrally molded in a state of being pressed are arranged at a predetermined position in which the interstitial area 20 is ensured. At this time, one of the composite floor slabs 1A is set at a predetermined position first, and then the other composite floor slab 1B is lowered from right above, thereby forming a predetermined spacing area 20 for one of the composite floor slabs 1A. It can be set in a secured state.
After that, in the interstitial area 20, the splicing plate 21 is placed above the pair of overhanging piece portions 13a, 13a with the overhanging piece portions 13a, 13a of the bottom steel plates 13 of the adjacent composite floor slabs 1A, 1B facing each other. While arranging, they are joined using a nut 22, a washer 23, and a high-strength bolt 24. - 特許庁

Next, the joining reinforcing bars 3 are arranged in the middle of the joint reinforcing bars 10, 10 adjacent to each other in the width direction X2, and the reinforcing reinforcing bars 5 are arranged above and below the joint reinforcing bars 10 and the joining reinforcing bars 3. After that, the filling concrete 4 is filled in the filling region 20 and hardened to form the filling portion 20A, and the construction of the joint portion 2 is completed.
The reinforcing reinforcing bars 5 arranged below the joint reinforcing bars 10 are temporarily placed between the joint reinforcing bars 10 and the bottom steel plates 13 when positioning the composite floor slabs 1A and 1B at predetermined positions. Construction of the reinforcing reinforcing bar 5 on the lower side can be efficiently performed.

Next, the operation of the joint structure of the composite floor slabs 1A and 1B described above will be described in detail with reference to the drawings.
In this embodiment, as shown in FIGS. 1 and 2(a) and (b), the mechanical fixing portions 10A, 10A of the joint reinforcing bars 10 of the adjacent composite floor slabs 1A, 1B are arranged coaxially with each other. By arranging the joint reinforcing bars 3 between the mechanical fixing portions 10A, 10A in the width direction X2 of the composite floor slabs 1A, 1B, the length of the mechanical fixing portion 10A can be shortened.
In this case, there is no need to displace the reinforcing bar joints in the width direction to prevent interference between the reinforcing bar joints as in the conventional art. can be made smaller. Therefore, it becomes possible to reduce the filling amount of the interstitial concrete 4 filled in the interstitial space 20, and the cost can be reduced.

Further, when the joining reinforcing bars 3 are arranged in the interstitial area 20, a simple work of inserting the joining reinforcing bars 3 from above between the mechanical fixing portions 10A arranged in the width direction X2. can be placed by Therefore, it is not necessary to insert a reinforcing reinforcing bar into the loop of the loop reinforcing bar as in the conventional art, and the labor and time required for construction can be reduced.

Further, in the present embodiment, even in the case of a member having a small number of joint reinforcing bars 10 or in the case of displacing both reinforcing bars in the width direction X2, it is possible to prevent twisting between the composite floor slabs 1A and 1B. can.

As described above, the present embodiment can be applied to joining various precast concrete members regardless of wide members such as the composite floor slabs 1A and 1B. The thickness of the member can be reduced without widening the interval of 20 . Therefore, it is possible to reduce the labor and time required for on-site joining, and the cost of the joint portion 2 can be reduced.

Further, in the present embodiment, since the reinforcing reinforcing bars 5 extend in a direction intersecting the joint reinforcing bars 10 and the joining reinforcing bars 3, the reinforcing reinforcing bars 5 are engaged with the widened portions 10a and 3a to Movement of the joint reinforcing bar 3 in the axial direction (joining direction X1) can be restricted. That is, by providing the reinforcing reinforcing bar 5, it is possible to restrain the joint reinforcing bar 10 and the joining reinforcing bar 3 from slipping out and bending due to movement in the axial direction (joining direction X1).

Furthermore, in the present embodiment, since the joint reinforcing bars 3 can be arranged at the same height as the joint reinforcing bars 10 in the thickness direction of the interstitial portion 20A, the thickness dimension of the interstitial portion 20A can also be kept small. can.
In addition, in this embodiment, in the construction of the reinforcing reinforcing bars 5, there is an advantage that a special jig is unnecessary because the work is simply adding reinforcing bars so as to sandwich the mechanical fixing portion 10A and the joining reinforcing bars 3 from above and below.

In addition, in the present embodiment, even in the composite floor slabs 1A and 1B made of synthetic members in which the bottom steel plate 13 is provided on the bottom surface of the concrete 14, the overhanging piece portion 13a of the bottom steel plate 13 and the splice plate in the filling portion 20A By joining 21 with high-strength bolts 24, they can be firmly and simply fixed.

In the joint structure of the precast concrete members of the present embodiment configured as described above, it is possible to reduce the labor and time required for construction, and it is possible to reduce the distance between the joint end surfaces 1a, 1a, thereby reducing the cost. reduction can be achieved.
Further, in this embodiment, even when the number of joint reinforcing bars 10 is small, it is possible to prevent twisting between the composite floor slabs 1A and 1B.

As described above, the joint structure of precast concrete members according to the present embodiment can reduce labor and time, and can reduce the thickness of the members, thereby reducing costs.
Further, in this embodiment, even when the number of joint reinforcing bars 10 is small, it is possible to prevent twisting between the composite floor slabs 1A and 1B.

Next, a joint structure for precast concrete members according to another embodiment will be described. Components having the same functions as those of the components of the first embodiment described above are denoted by the same reference numerals, and detailed description thereof will be omitted to avoid duplication of description.

(Second embodiment)
As shown in FIGS. 5 and 6, the joint structure of the precast concrete member according to the second embodiment is such that the bottom steel plate 13 is omitted from the composite floor slab 1 of the first embodiment described above, and the joint reinforcing bars 10 are arranged in the thickness direction. This structure is applied to the joint portion 2A of the PC floor slabs 1 (1C, 1D) (precast concrete members) arranged in two upper and lower stages. That is, the PC floor slabs 1C and 1D are embedded in the concrete 14 so that the upper and lower joint reinforcing bars 10 and 10 protrude the mechanical fixing portions 10A at the tips from the joint end face 1a.

The joint portion 2A of the second embodiment consists of a joint reinforcing bar 10 having a mechanical anchoring portion 10A with a widened portion 10a at the tip, and the adjacent PC floor slabs 1 (1C, 1D) in the interstitial region 20. It is composed of joining reinforcing bars 3 for joining, interstitial concrete 4 and reinforcing reinforcing bars 5 .

The joining reinforcing bars 3 are provided in two upper and lower stages at positions of the same height as the joint reinforcing bars 10, 10 in the upper and lower two stages. The reinforcing reinforcing bars 5 are provided so as to be connected to the mechanical fixing portions 10A of the joint reinforcing bars 10 arranged respectively in the upper and lower stages in the interstitial area 20 at positions above and below the joining reinforcing bars 3 .

In the joint portion 2A of the second embodiment, similarly to the above-described first embodiment, it is possible to reduce labor and time, and it is possible to reduce the thickness of the member, so that the cost can be reduced. . Moreover, even when the number of joint reinforcing bars 10 is small, it is possible to prevent twisting between the PC floor slabs 1C and 1D.

(Third embodiment)
As shown in FIGS. 7 and 8, the joint portion 2B (joint structure) of the composite floor slab 1 (1E, 1F) (precast concrete member) according to the third embodiment is applied to the composite floor slab 1 of the first embodiment. The joint part 2 is the same as the joint part 2, and has a structure in which the reinforcing plate 6 is used in the joint part 2B and the number of reinforcing reinforcing bars 5 is reduced.
That is, the composite floor slabs 1E and 1F are embedded in the concrete 14 so that the joint reinforcing bars 10 protrude from the joint end surface 1a of the mechanical fixing portions 10A, and the bottom steel plate 13 and the concrete 14 are connected as in the first embodiment. It is integrally molded.

The joint portion 2B includes a splicing plate 21, a nut 22, a washer 23, a high-strength bolt 24, and a splicing plate 21, a nut 22, a washer 23, and a high-strength bolt 24 that join the overhanging pieces 13a, 13a of the bottom steel plates 13 of the adjacent composite floor slabs 1E, 1F. The joint reinforcing bars 10 and the joint reinforcing bars 3 having a mechanical fixing portion 10A between the joint end surfaces 1a, 1a of the joint reinforcing bars 10, 10 and the joint reinforcing bars 10, 10, and the joint reinforcing bars 10, 10 and the joint reinforcing bars 3, respectively. Reinforcement connected by engaging from above the interstitial concrete 4 filled so as to bury the joint reinforcing bar 10 and the reinforcing reinforcing bar 5 connected to the upper side of the joining reinforcing bar 3, and the joint reinforcing bar 10 and the joining reinforcing bar 3 from above a plate 6;

As shown in FIG. 9, the reinforcing plates 6 are a plurality of mechanical anchors protruding from the joint end faces 1a, 1a of the adjacent composite floor slabs 1E, 1F and arranged side by side at predetermined intervals in the extending direction. The joint reinforcing bar 10 having the portion 10A is engaged from above to connect the joint reinforcing bar 10 having the plurality of mechanical fixing portions 10A. It is embedded in concrete 4.

The reinforcing plate 6 has a support member 60 extending in one direction and a plurality of hook-like engagement pieces 61 forming the engagement recesses 6a at predetermined intervals along the length direction of the support member 60. there is The hook-shaped engagement pieces 61 are provided at intervals corresponding to the arrangement intervals of the mechanical fixing portion 10A and the joining reinforcing bars 3 in the width direction X2. The engaging concave portion 6a is provided so that the mechanical fixing portion 10A and the portion other than the widened portions 10a and 3a of the joining reinforcing bar 3 can be engaged. The reinforcement plate 6 is engaged with the mechanical fixing portion 10A and the joining reinforcing bar 3 in the engaging recess 6a in the interstitial region 20 with the length direction directed in the width direction X2.

As shown in FIGS. 7 and 8 , only two reinforcing reinforcing bars 5 are connected to the upper side of the mechanical fixing portion 10A and the joining reinforcing bars 3 . In this way, in the third embodiment, by providing the reinforcing plate 6, the reinforcing reinforcing bars 5 can be omitted or the number of arranged reinforcing bars can be reduced. As in this embodiment, when the reinforcing reinforcing bars 5 are provided in addition to the reinforcing plate 6, the mechanical fixing portions 10A, 10A of the adjacent synthetic floor slab 1E and the other synthetic floor slab 1F are The overlapped joint length can be shortened.

As described above, in the joint portion 2B of the third embodiment, the reinforcing plate 6 is provided in a state of extending in the width direction X2, which is the direction intersecting the joint reinforcing bar 10 and the joining reinforcing bar 3. Therefore, the reinforcing plate 6 can be engaged with the widened portions 10a and 3a to restrict movement of the joint reinforcing bar 10 and the joining reinforcing bar 3 in the axial direction (joining direction X1). That is, by providing the reinforcing plate 6, it is possible to restrain the joint reinforcing bars 10 and the joining reinforcing bars 3 from slipping out and bending due to movement in the axial direction (joining direction X1).
Moreover, the work of engaging the reinforcing plate 6 with the mechanical fixing portion 10A and the joining reinforcing bar 3 from above is simple, and there is an advantage that no special jig is required.

Although the embodiments of the joint structure for precast concrete members according to the present invention have been described above, the present invention is not limited to the above embodiments, and can be modified as appropriate without departing from the scope of the present invention.

For example, in the present embodiment, the reinforcing reinforcing bars 5 are provided on at least one of the upper side and the lower side of the mechanical fixing portion 10A and the joining reinforcing bars 3. However, the reinforcing bars 5 are not limited to being provided. , can be omitted, and the number of lines to be arranged can be changed as appropriate.

In addition, in the present embodiment, as the reinforcing bars of the joint reinforcing bars 10 and the joining reinforcing bars 3, T-head construction method reinforcing bars (registered trademark, manufactured by Shimizu Corporation) in which the widened portions 10a and 3a are formed in a T shape are used. It is also possible to employ shaped reinforcing bars.

In addition, it is possible to appropriately replace the components in the above-described embodiments with well-known components without departing from the scope of the present invention.

1, 1A, 1B, 1E, 1F Synthetic floor slabs (precast concrete members)
1C, 1D PC floor slab (precast concrete member)
2, 2A, 2B joint part (joint structure)
3 Joining reinforcing bar 3a Widening part 4 Filling concrete 5 Reinforcing reinforcing bar 6 Reinforcement plate 10 Joint reinforcing bar 10A Mechanical fixing part 10a Widening part 13 Bottom steel plate 13a Overhanging piece (protruding part)
20 Spacer area 20A Spacer part 21 Splice plate 24 High-strength bolt X1 Joining direction X2 Width direction

Claims (3)

A joint structure of precast concrete members for joining precast concrete members formed by integrally molding reinforcing bars and concrete,
a joint reinforcing bar having a widened portion at its tip end and a mechanical fixing portion arranged so as to protrude from the joint end surface of the precast concrete member on the side of the widened portion;
interstitial concrete filled in interstitial areas between the joint end faces of the precast concrete members joined to each other so as to bury the mechanical fixing portion;
a joint reinforcing bar having widened portions at both ends and arranged in the interstitial region so that its axial direction is parallel to the axial direction of the joint reinforcing bar;
The mechanical fixing portions of the precast concrete members to be joined are arranged on a coaxial line,
The joining reinforcing bars are arranged between the mechanical fixing portions in the width direction of the precast concrete member ,
In the interstitial portion where the interstitial space is filled with the interstitial concrete, the mechanical fixing portion and the joining reinforcing bar are provided at the same height position in the thickness direction of the interstitial portion,
A reinforcing reinforcing bar is provided that is connected to at least one of upper and lower sides of the mechanical fixing portion and the joining reinforcing bar and extends in a direction that intersects the mechanical fixing portion and the joining reinforcing bar . A joint structure of precast concrete members, characterized by: A bottom steel plate projecting from the joint end surface is integrally provided on the bottom surface of the concrete of the precast concrete member,
a splice plate disposed so as to bridge the projecting portions of the bottom steel plates of the adjacent precast concrete members;
a high-strength bolt that joins the splicing plate and the bottom steel plate;
The joint structure of precast concrete members according to claim 1 , characterized by comprising: 3. The precast according to claim 1, further comprising a reinforcing plate which is provided so as to be engageable with the plurality of mechanical fixing portions from above and which connects the plurality of mechanical fixing portions. Joint structure of concrete members.

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