JP7260849B2 - Precast concrete member and its connection structure - Google Patents

Description

The present invention relates mainly to floor slabs, particularly precast concrete members used as bridge floor slabs, and their connecting structures.

In Japan, social and economic infrastructure such as roads, railways, rivers, and ports were built intensively during the period of high economic growth. There is an urgent need for maintenance and renewal, but in the superstructure of bridges where roads and railways are laid, if the floor slab is severely damaged, it will need to be replaced. In the case of a girder on which an RC floor slab is bridged, a countermeasure to replace the RC floor slab with a precast concrete floor slab of RC structure or PC structure (hereinafter simply referred to as a precast floor slab) is widely adopted. there is

When replacing a floor slab using precast floor slabs, after removing the existing floor slabs, the precast floor slabs are arranged along the bridge axis direction, and then PC steel materials are inserted through these precast slabs. A construction method is adopted in which the precast floor slabs are connected to each other by introducing tensile force (Patent Document 1).

On the other hand, instead of completely removing the existing floor slabs, for example, if one of the two lanes is made passable while the other is partially removed and the floor slabs are replaced, it will be possible to avoid complete road closures during the construction period. (Patent Document 2).

JP 2017-82496 A JP 2016-98490 A

In the above partial removal, if the precast deck slabs are placed side by side in the direction perpendicular to the bridge axis, the insertion holes for the PC steel will be open on both sides of the superstructure. In order to introduce the stress, a scaffold must be constructed separately, and the length of the PC steel material is lengthened. There is a concern that storage costs will increase.

Therefore, the applicant of the present invention provided a notch in at least one of the two precast concrete members, and then used the two precast concrete members described above so that the PC steel material was positioned in the notch. The member and the PC steel material are placed side by side at the construction site, then concrete is placed in the notch to provide a tensile force transmission part in the notch, and the PC steel material is buried in the tensile force transmission part. A connection structure is under development in which two precast concrete members are pulled together by the tensile force of the PC steel material. According to this connection structure, it is not necessary to insert a long length of PC steel material into the two precast concrete members at the construction site. The scaffolding for the insertion work is no longer required, and the tensile force of the PC steel material, which has been introduced in advance at the factory or the like, can be released at the construction site, so there is no need for a scaffolding for introducing the tensile force. becomes.

Here, since the tensile force transmission part described above is an important structural element for transmitting load between the PC steel material or the fixing plate attached to the PC steel material and the precast concrete member, it has excellent strength performance. It is desirable to use high-quality concrete, such as room-temperature-hardening ultra-high-strength fiber-reinforced concrete, but in that case, from the economic point of view, the amount of concrete used should be kept as low as possible to reduce costs. Desired.

However, in a state where two precast concrete members are arranged in advance, a notch is provided regardless of the case where the connection unit in which the PC steel material is incorporated is arranged in the notch provided in each of the precast concrete members. In the case where the precast concrete member with a part of the connection unit is placed first, and then the precast concrete member with a part of the connection unit attached in advance is placed after that, if the width of the notch is too narrow, the remaining part of the connection unit will be cut. Since it tends to interfere with the reinforcing bars protruding from the notch facing inner surface, it takes time to lower the precast concrete member, and there is concern that the lowering work itself will become difficult.

In other words, if the width of the cutout is made smaller to reduce the amount of concrete used, it becomes difficult to unload the work at the construction site. However, there has been a problem of an increase in the number of parts and an increase in cost.

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide a precast concrete member and its connection structure that can reduce the amount of concrete used while maintaining good workability in lifting work. aim.

In order to achieve the above object, the precast concrete member according to the present invention, as described in claim 1, has an opening as a joint-side opening on the side of the joint-side end face, and is perpendicular to the joint-side end face so as to be back-to-back. A notch that opens as an insertion-side opening is provided on one of the non-joint surfaces of a pair of non-joint surfaces that extend to the same direction, and a tensile force transmission part made of post-cast concrete is attached to the notch. A precast concrete member that can be provided in a predetermined range including the end of the PC steel material or in a state where the fixing means attached to the end is embedded,
The facing inner surface distance of the notch along the direction parallel to the pair of non-joint surfaces and parallel to the joint-side end surface is maximum at the insertion-side opening, and continuously or discontinuously as it becomes deeper from the insertion-side opening. The notch is formed so as to decrease continuously.

Moreover, the precast concrete member which concerns on this invention makes the opposing inner surface of the said notch each the stepped inner surface.

Further, in the precast concrete member according to the present invention, the reinforcing bars are arranged in two stages in a direction parallel to the pair of non-joining surfaces and parallel to the joining side end surface, and the reinforcing bars on the side closer to the insertion side opening are arranged in two stages. is the first distributing reinforcement, and the rebar on the far side from the insertion side opening is the second distributing reinforcement, and the rebars along the direction perpendicular to the joint side end face are arranged in two stages and the insertion The reinforcing bar on the side closer to the side opening is defined as a first main reinforcing bar, the reinforcing bar on the side farther from the insertion side opening is defined as a second main reinforcing bar, and the portions of the first distributing bars extending from the opposed inner surfaces of the notches are respectively The protruding ends are arranged separately so as to be separated from each other, and the second force distributing bars are arranged continuously so as to extend from one side of the facing inner surface of the notch to the other side.

Moreover, the precast concrete member which concerns on this invention comprises prestressed concrete.

Further, as described in claim 5, the connection structure of precast concrete members according to the present invention is such that the first precast concrete member and the joint side end surface of the first precast concrete member face each other. The precast concrete member according to any one of claims 1 to 4 as a second precast concrete member juxtaposed, and post-cast concrete in the notch so as to be continuously integrated with the second precast concrete member. and a predetermined range including one end or a fixing means attached to the one end is embedded in the first precast concrete member, and the remainder including the other end and a PC steel material in which the fixing means attached to the range of or the other end is embedded in the tensile force transmission part, and the first precast concrete member and the second precast concrete member, They are attracted to each other by the tensile force of the PC steel material which reacts with the compressive force acting on each other on the joining side end faces.

In addition, as described in claim 6, the connection structure of precast concrete members according to the present invention includes the precast concrete member according to any one of claims 1 to 4 as a third precast concrete member, and the third precast concrete member. The precast concrete member according to any one of claims 1 to 4 as a fourth precast concrete member arranged so that the joint side end face and the joint side end face of the precast concrete member of 3 are opposed to each other, and the third two tensile force transmission parts respectively provided with post-cast concrete in each of the notches belonging to each of the precast concrete members and the fourth precast concrete member so as to be continuously integrated with each of the precast concrete members; A predetermined range including one end or a fixing means attached to the one end is embedded in the tensile force transmission part belonging to the third precast concrete member among the tensile force transmission parts, The remaining range including the other end in the tensile force transmission part belonging to the precast concrete member of the above, or a PC steel material in which the fixing means attached to the other end is embedded, and the third precast The concrete member and the fourth precast concrete member are drawn to each other by the tensile force of the PC steel material, which reacts with the compressive force acting on the joint side end faces of the concrete member and the fourth precast concrete member.

In the precast concrete member according to the present invention, one of the pair of non-joint surfaces that are opened as the joint-side opening on the joint-side end face and extend in the orthogonal direction so as to be back-to-back from the joint-side end face A notch that opens as an insertion side opening is provided on the side of the surface, but the notch is parallel to the pair of non-bonding surfaces and parallel to the bonding side end surface (hereinafter referred to as the width direction). The distance between opposing inner surfaces (hereinafter referred to as width W) is maximized at the insertion side opening and is formed so as to decrease continuously or discontinuously as the depth increases from the insertion side opening .

With this configuration, the width of the notch is widened at the opening on the insertion side, so that the work of inserting the connecting unit into which the PC steel material is incorporated is facilitated.

In addition, since the width of the notch decreases as the depth increases from the insertion side opening , the cross-sectional area of the notch is equivalent to the case where the width is constant with respect to the depth (rectangular cross section). Since the contact area between the tensile force transmitting portion provided in the notch and the precast concrete member is larger than in the case of the rectangular cross section, the amount of concrete used can be reduced.

Typical examples of precast concrete members are floor slabs, especially floor slabs for bridges, but they may be manufactured for other parts such as walls, columns, and beams, and may also be used for harbors and other civil engineering structures. It can be applied not only to objects but also to building structures.

In addition, when the precast concrete member is a floor slab, the surface facing another precast concrete member to be connected among the peripheral surfaces, the surface that is vertical in the connected state will be the joint side end surface, and will be horizontal in the connected state. The extending surfaces (upper surface and lower surface) form a pair of non-joining surfaces, and in the case of a wall, among the peripheral surfaces, the surface facing another precast concrete member to be connected, and the surface that is vertical or horizontal in the connected state. It becomes the joint side end surface, and in the connected state, the vertically extending surfaces (side surfaces) become a pair of non-joined surfaces. In this case, the vertical surface is the joint side end surface, and in the connected state, the horizontally extending surfaces (upper and lower surfaces) are a pair of non-joint surfaces.

The insertion side opening is formed in either one of the pair of non-bonding surfaces, but this does not exclude the configuration in which another opening, so to speak, the non-insertion side opening is formed in the other non-bonding surface. However, according to the configuration in which such a non-insertion side opening is formed, when reinforcing bars are arranged, the covering area of the reinforcing bars becomes narrow and clogged with coarse aggregate, and the solidified state of the concrete around the reinforcing bars becomes poor. can be prevented.

The notch may have any cross-sectional shape as long as it is formed such that its width is maximum at the insertion side opening and decreases continuously or discontinuously as it becomes deeper from the insertion side opening . A configuration in which the inner surfaces facing each other are slanted with respect to the non-bonded surface, and a configuration in which one of the inner surfaces facing each other is slanted and the other is upright. If it is the inner surface, the contact area between the tensile force transmission part and the precast concrete member can be further increased, and as a result, the total length of the notch can be significantly shortened, and the amount of concrete used can be further reduced. It becomes possible to

In addition, due to the tenon action (dowel action) of the stepped inner surface, the resistance to the external force in the direction orthogonal to the pair of non-bonded surfaces is also improved.

Arrangement of the reinforcing bars in the precast concrete member is arbitrary, but the reinforcing bars along the width direction of the notch are arranged in two stages, and the reinforcing bars on the side closer to the opening on the insertion side are used as the first distributing bars. , the reinforcing bar on the far side from the insertion side opening is used as the second distributing bar, and the reinforcing bar on the side near the insertion side opening is used as the first distributing bar. The main reinforcing bars, the reinforcing bars on the far side from the insertion side opening are used as second main reinforcing bars, and the first force distribution bars are divided and arranged so that the portions extending from the opposing inner surfaces of the notches are separated from each other as protruding ends, A typical example is a configuration in which the second force distributing bar is continuously arranged so as to extend from one side of the opposing inner surface of the cutout to the other side.

In the above typical example, the PC steel material is also arranged in two stages, and on the side closer to the insertion side opening, it is arranged in the space sandwiched between the projecting ends of the first force distributing bars, and on the side farther from the insertion side opening , are arranged to intersect the second distributing bar.

The precast concrete member can be made of reinforced concrete or fiber reinforced concrete, but if it is made of prestressed concrete, it is possible to improve strength and durability.

Further, in the connection structure of precast concrete members according to the present invention, the PC steel material is not passed through the two precast concrete members, but is arranged in each of the two precast concrete members so that each end of the PC steel material is not exposed. as a configuration.

That is, in the connection structure of precast concrete members according to the present invention, one of the two precast concrete members is the first precast concrete member and the other is the second precast concrete member, and the first precast concrete member One end of the PC steel material or the fixing means attached to the end is embedded, and a tensile force transmission portion is provided in the notch of the second precast concrete member with post-cast concrete, and the tensile force transmission portion is provided with PC. The other end of the steel material or the anchoring means attached to the end is buried, or the tensile force transmission part is post-cast in each notch formed in the third precast concrete member and the fourth precast concrete member. It is made of concrete, and each end of the PC steel material or the fixing means attached to each end is embedded in each of the tensile force transmission parts, and the two precast concrete members are separated by the tensile force of the PC steel material. They are arranged to attract each other.

In this way, there is no need to insert a long PC steel material into two precast concrete members at the construction site, and a scaffold for the insertion work is not required. Since what is introduced in advance can be released at the construction site, scaffolding for releasing tensile force is not necessary.

By the way, the tensile force release of the PC steel material in the present invention is similar to the conventional connection structure of the PC steel material penetration type in the sense that it introduces a prestress of compressive force to the concrete, but in the present invention, two Compressive force is generated only in the concrete area extending near the joint side end surface of the precast concrete member, that is, only in the area required as a reaction force for attracting, and the compressive force is introduced to the entire precast concrete member. This is clearly different from the conventional connection structure in which the members are prestressed concrete structures.

As described above, the configuration for embedding the ends of the PC steel material in concrete differs depending on whether a notch is formed in only one of the two precast concrete members or notches are formed in both of them. In the former, one end of the PC steel material is embedded in the precast concrete member on the side where the notch is provided, and the other end is integrated with the precast concrete member on the side where the notch is provided. In the latter, each end of the PC steel material is embedded in each tensile force transmission part provided with post-cast concrete so as to be continuous and integrated with each precast concrete member. , etc. are respectively embedded.

Here, when the tensile force of the PC steel material is balanced with the compressive force of the surrounding concrete through the adhesion of the PC steel material to the peripheral surface of the PC steel material, the above-described burying structure has a predetermined range including one end and the other end. and the rest of the area, including, respectively, one end when balancing the tensile force of the PC steel with the compressive force of the surrounding concrete through the bearing pressure in the anchoring means attached near each end It is assumed that the fixing means attached to the part and the fixing means attached to the other end are embedded respectively.

As long as the tensile force transmission part is provided so as to be continuous and integrated with the precast concrete member, it is possible to configure it with any structure such as reinforced concrete, fiber reinforced concrete, etc., but these tensile force transmission parts are made of PC steel material or Since it is an important structural element for transmitting load between the anchor plate attached to the PC steel material and the precast concrete member, the post-cast concrete that constitutes them is high-quality concrete with excellent strength performance. In particular, it is desirable to employ cold-curing ultra-high-strength fiber-reinforced concrete.

FIG. 2 is a diagram showing a state in which the connection structure 104 of precast concrete members according to the first embodiment is applied to the floor slab 101 of a bridge, where (a) is a plan view and (b) is an arrow seen from the CC line direction. view. FIG. 3 is a diagram showing a precast concrete member 103b used in a precast concrete member connection structure 104, (a) is a plan sectional view, (b) is a vertical sectional view along line DD, and (c) is EE. A vertical section view along a line. FIG. 2 is a diagram showing a connection structure 104 of precast concrete members, (a) being a horizontal sectional view and (b) being a vertical sectional view taken along line FF. FIG. 2 is a view of the connection unit 1 used when constructing the connection structure 104 of precast concrete members, (a) is a front view, and (b) is an assembly drawing seen from the front. FIG. 2 is an assembly perspective view of the connection unit 1; FIG. 2 is an arrow view showing a part of the connection unit 1 in cross section, where (a) is an arrow view as viewed in the direction of line AA, and (b) is a view as viewed in the direction of line BB. 4A and 4B are diagrams showing a procedure for introducing tensile force to the PC steel bar 2 of the connection unit 1. FIG. The figure which showed the construction|assembly procedure of the connection structure 104 of a precast-concrete member as a procedure of replacing the floor slab of a bridge. FIG. 10 is a diagram showing how the deck slabs of the bridge are subsequently replaced as before the post-cast concrete is poured, (a) being a horizontal cross-sectional view and (b) being a vertical cross-sectional view taken along line GG. A vertical cross-sectional view along line HH showing how the deck slabs of the bridge are subsequently replaced, as before placing post-cast concrete. A horizontal cross-sectional view showing how the deck slab of the bridge is subsequently replaced after the post-cast concrete is placed. It is a diagram showing how the deck slab of the bridge is subsequently replaced, (a) is a plan view showing the state of releasing the tensile force of the PC steel rod 2, and (b) is the released PC FIG. 2 is a plan view showing how precast concrete members 103a and 103b are connected to each other by a tensile force of a steel bar 2; The figure which showed the modification of the connection unit 1. FIG. FIG. 11 is a horizontal cross-sectional view showing another procedure for constructing a connection structure 104 of precast concrete members; The vertical sectional view which showed the precast-concrete member which concerns on a modification. FIG. 10 is a diagram showing a state in which the connection structure 144 of precast concrete members according to the second embodiment is applied to a floor slab 141 of a bridge, (a) is a plan view, and (b) is an arrow viewed from the direction of the II line. view. FIG. 14 is a view showing a connection structure 144 of precast concrete members, (a) being a horizontal sectional view, and (b) being a vertical sectional view taken along line JJ. Fig. 3 shows the construction procedure of the connecting structure 144 of precast concrete members as a state before pouring post-cast concrete in the procedure of replacing the floor slab of the bridge, (a) is a horizontal sectional view, (b) is a K - vertical section along line K; FIG. 14 is a horizontal cross-sectional view showing the procedure for constructing a connecting structure 144 of precast concrete members as a state after post-cast concrete is placed in the procedure for replacing the floor slabs of the bridge.

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a precast concrete member and its connection structure according to the present invention will be described below with reference to the accompanying drawings.

[First embodiment]
FIG. 1 is an overall view showing a state in which a connecting structure of precast concrete members according to the present invention is applied to a floor slab 101 of a bridge. It is an arrow view.

As shown in the figure, the floor slab 101 is made up of rectangular precast concrete members 103a and 103b placed side by side in the direction perpendicular to the bridge axis and spanned over the main girder 102 of the bridge. The connecting structure 104 of precast concrete members is constructed by connecting such precast concrete members 103a and 103b in the direction perpendicular to the bridge axis.

By forming the precast concrete members 103a and 103b from prestressed concrete, durability and strength can be improved.

Here, as shown in FIG. 2, the precast concrete members 103a and 103b are connected so that their joining side end surfaces 115a and 115b face each other, and the precast concrete member 103b is provided with a notch 114. , the notch opens as a joint-side opening 161 on the side of the joint-side end surface 115b, and a pair of non-joint surfaces (left and right in FIG. 162a as one of the non-bonding surfaces, an insertion-side opening 163 is opened, and a non-insertion-side opening 164 is opened on the bottom surface 162b. Through the side opening 163, connecting units 1, 1, which will be described later, are inserted and arranged in two stages, upper and lower.

The notch 114 extends in a direction parallel to the upper surface 162a and the lower surface 162b, which are a pair of non-bonding surfaces, and parallel to the bonding side end surface 115b (the vertical direction in FIG. ) is maximum (W _max ) at the insertion-side opening 163, decreases discontinuously as the depth increases from the insertion-side opening , and reaches the non-insertion-side opening. 16
4, but particularly in this embodiment, as shown in FIG.

In the precast concrete member 103b, the reinforcing bars along the width direction of the notch 114 are arranged in two stages, and the reinforcing bar on the side closer to the insertion side opening 163 is a distributing bar 167a as a first distributing bar. The reinforcing bar on the far side from the opening 163, that is, on the side closer to the non-insertion side opening 164 is used as a distributing bar 167b as a second distributing bar, and the reinforcing bar along the direction perpendicular to the joint side end surface 115b is arranged in two stages. The reinforcing bar on the side closer to the insertion side opening 163 by being spaced apart is the main reinforcing bar 168a as the first main reinforcing bar, and the reinforcing bar on the side far from the insertion side opening 163, that is, the side close to the non-insertion side opening 164 is the second main reinforcing bar. As for the force distributing bar 168b, the distributing bar 167a is divided and arranged so that the portions extending from the facing inner surfaces 166, 166 of the notch 114 are separated from each other as protruding ends, and the distributing bar 167b is arranged as a cut. They are continuously arranged so as to extend from one of the opposing inner surfaces 166, 166 of the cutout 114 to the other.

Here, the protruding portion of the force distributing bar 167a is formed so that the post-cast concrete is continuously integrated with the precast concrete member 103b when the tensile force transmission part 113 described later is provided in the notch 114 with the post-cast concrete. is appropriately set.

As shown in FIG. 3, the connecting structure 104 of precast concrete members includes a disk-shaped fixing plate 3a as fixing means attached to one end of a PC steel rod 2 as a PC steel material to a precast concrete member 103a. A disk-shaped fixing plate 3b as a fixing means attached to the other end is attached to a tensile force transmission portion 113 made of post-cast concrete provided in a notch 114 so as to be continuously integrated with the precast concrete member 103b. The precast concrete members 103a and 103b are buried respectively, and a joint portion 116 also made of post-cast concrete is provided between the joint side end surfaces 115a and 115b of the precast concrete members 103a and 103b. By balancing the tensile force of the rod 2 with the compressive force generated in the surrounding concrete, and by taking the compressive reaction force from the joint side end surfaces 115a and 115b of the precast concrete members 103a and 103b, precasting is performed by the tensile force of the PC steel rod. Concrete members 103a and 103b are pulled together and connected.

As can be seen in FIG. 1B, the PC steel material 2 and the fixing plates 3a, 3b are arranged in two sets in two upper and lower stages along the thickness direction of the precast concrete members 103a, 103b.

The joint side end face 115b of the precast concrete member 103b is formed with a ridge in the width direction of the notch 114 so as to increase the bonding strength between the precast concrete member and the joint portion 116, and the joint of the precast concrete member 103a. The side end face 115a is also formed with a ridge in the width direction of the notch 114 so as to increase the bonding strength between the precast concrete member and the joint 116. As shown in FIG.

The PC steel rod 2 and the fixing plates 3a and 3b are part of the elements constituting the connection unit 1, which will be described later. Although embedded, such other components are omitted from FIG. 3 because they do not exhibit any particular action as a connecting structure.

4 to 6 are diagrams showing the connection unit 1 used in the connection structure 104 of precast concrete members. As shown in these figures, the connection unit 1 includes a PC steel bar 2, fixing plates 3a and 3b, a pair of cylindrical reaction force members 4a and 4b as reaction force members, and a reaction force generating and releasing mechanism. A pair of female screw members 5a and 5b are provided.

Cylindrical reaction members 4a and 4b are each composed of a hollow cylindrical member, and compressive force, which is a reaction force for introducing tensile force to the PC steel rod 2, is transmitted to the vicinity of each end of the PC steel rod 2. and coaxially with the PC steel rod 2 so that the PC steel rod 2 is inserted therethrough. A tensile force can be introduced to the PC steel bar 2 by applying the above-mentioned compressive force to the facing surface.

The female screw members 5a and 5b are screwed into male screws 9a and 9b which are right-handed screws formed at the opposite ends 8a and 8b of the cylindrical reaction members 4a and 4b, respectively. By turning them counterclockwise while they are screwed together, the opposed ends 8a of the cylindrical reaction members 4a and 4b receive a reaction force in the material axial direction from each other via an annular sliding member 10, which will be described later. , 8b are spread apart to generate the compressive force described above, and by rotating in the opposite direction (clockwise), the opposite ends 8a, 8b can be brought closer to release the compressive force. It's like

As can be seen in FIG. 6, the connection unit 1 has one end in the annular space between the inner peripheral surface of the opposing end 8a and the outer peripheral surface of the PC steel bar 2, and the inner peripheral surface of the opposing end 8b and the PC steel bar. 2, the other ends of which can be inserted into the annular spaces between the outer peripheral surfaces of the tubular member 4a and 4b. While permitting the relative movement of the portions 8a and 8b in the direction of the material axis, the relative movement of the opposing end portions 8a and 8b in the direction perpendicular to the material axis is constrained.

Further, in the connecting unit 1, an annular sliding member 10 is arranged between the female screw members 5a and 5b so as to be sandwiched between the female screw members 5a and 5b.

The ring-shaped sliding member 10 has a center plate 11 projecting from the peripheral surface of the end guide member 6 in the shape of a flange, and through holes 13a and 13b arranged on both sides of the center plate 11 for allowing the end guide member 6 to pass therethrough. It is composed of formed side plates 12a and 12b.

Here, when the female screw members 5a and 5b are rotated counterclockwise, a frictional force is generated on the contact surfaces between the central plate 11 and the side plates 12a and 12b in accordance with the magnitude of the compressive force acting therebetween. However, the central plate 11 is designed so that the rotational operation of the female screw members 5a and 5b is not hindered by this frictional force, in other words, the contact surfaces between the central plate 11 and the side plates 12a and 12b are sliding surfaces. is constructed by covering both sides of a suitable base material with PTFE (polytetrafluoroethylene), and the side plates 12a and 12b are constructed of stainless steel plates.

According to such a configuration, the female screw members 5a and 5b receive reaction force from each other in the material axial direction via the annular sliding member 10, and the cylindrical reaction force members 4a and 4b are rotated by their rotational operation. The opposing ends 8a and 8b are pushed apart to separate them, and a compressive force generated in the cylindrical reaction members 4a and 4b can introduce a tensile force to the PC steel bar 2. As shown in FIG.

The side plates 12a, 12b are preferably constructed so that the compressive force from the internally threaded members 5a, 5b is evenly transmitted to each surface of the center plate 11. As shown in FIG.

Next, a case where the procedure for constructing the connecting structure 104 of precast concrete members according to the present embodiment is applied to bridge floor slab replacement will be described.

First, in order to introduce tensile force to the PC steel rods 2 constituting the connection unit 1, the female screw members 5a and 5b are operated so that the axial deformation of the cylindrical reaction members 4a and 4b is restrained in the contracted state. do.

Specifically, the process of introducing a tensile force to the PC steel bar 2 will be described. The member 6, the female screw member 5b, and the cylindrical reaction member 4b are sequentially inserted. At this time, one end of the material end guide member 6 is inserted into the opposing end 8a of the tubular reaction member 4a, and the other end is inserted into the opposing end 8b of the tubular reaction member 4b.

Next, the female threaded members 5a and 5b are screwed into the male threads 9a and 9b of the cylindrical reaction members 4a and 4b, and the female threaded members 5a and 5b are turned clockwise to connect the female threaded members to the opposite ends. The fixing plates 3a and 3b are temporarily retracted from the portions 8a and 8b, and in this state, the fixing plates 3a and 3b are attached to the respective ends of the PC steel rod 2 by, for example, screwing.

Next, as shown in FIG. 7(a), the female screw members 5a and 5b are turned counterclockwise to bring their opposing surfaces into contact with the side plates 12a and 12b of the annular slide member 10, respectively, and from this state, Continue rotating.

In this way, as shown in the figure, the female screw members 5a and 5b receive axial reaction force from each other through the annular sliding member 10, and the opposite ends of the tubular reaction force members 4a and 4b are moved. As the parts 8a and 8b are pushed apart to separate the opposite ends, a compressive force is generated in the cylindrical reaction members 4a and 4b. A tensile force is introduced in

Here, as the female screw members 5a and 5b are rotated, the side plates 12a and 12b rotating together with the female screw members come into contact with respective surfaces of the central plate 11, as shown in FIG. 7(b). When viewed from the side of the female screw members 5a and 5b, both tend to rotate in opposite directions, clockwise, but as described above, the central plate 11 and the side plates 12a and 12b are circularly shaped so as to cause slippage. The side plates 12a and 12b slide on the respective surfaces of the central plate 11 because the slide member 10 is configured and the frictional force generated on the contact surface is small, so that the female screw members 5a and 5b can be rotated. There is no danger of being hindered.

The material end guide member 6 allows the opposite ends 8a and 8b to move relative to each other in the axial direction as the cylindrical reaction members 4a and 4b expand and contract. The material end guide member 6 does not restrain relative movement in the material axial direction at the opposed ends 8a and 8b accompanying the separation of the material 4b.

On the other hand, as the female screw members 5a and 5b are rotated, the compressive force generated in the cylindrical reaction members 4a and 4b increases, causing buckling, and the central plate 11 constituting the annular sliding member 10. The frictional force generated on each surface of the cylindrical reaction member 4a, 4b is uneven in the circumferential direction, or the balance of the frictional force acting on both surfaces is lost. As shown in 7(c), there is a case where a lateral slip occurs. Therefore, even if a load that tends to cause a lateral slip occurs, the lateral slip load is applied to the inner peripheral surfaces of the opposed ends 8a and 8b and the outer periphery of the end guide member 6 as shown in FIG. The opposite ends 8a and 8b of the cylindrical reaction members 4a and 4b are supported by the end guide members 6 through load transmission between the surfaces, and there is no risk of lateral slippage.

After the introduction of tensile force to the PC steel rods 2 constituting the connection unit 1 is completed, the connection unit 1 is two-stepped into the precast concrete member 103a so that the fixing plate 3a of the connection unit is embedded in the precast concrete member 103a. Fabricate the precast concrete members to be placed.

On the other hand, the precast concrete member 103b is manufactured so that the notch 114 is formed in the precast concrete member 103b in a separate process from the introduction of the tensile force to the connecting unit 1. As shown in FIG.

Next, the precast concrete member 103a to which the connection units 1, 1 are pre-attached so as to form two upper and lower stages, and the precast concrete member 103b in which the notch 114 is formed are transported, and the floor slabs of the bridge at the construction site are transported. Bring to replacement site.

For example, in the case of a bridge with two lanes on one side, if only one of the lanes is closed and the remaining lane is allowed to pass, it is possible to avoid a complete road closure and traffic congestion. Therefore, taking this as an example, first, of the existing floor slabs 121a and 121b to be replaced, as shown in FIG. ), a precast concrete member 103b having a notch 114 formed at the removed location is installed.

Next, after removing the existing floor slab 121a as shown in FIG. 1(c), a precast concrete member 103a to which the connection units 1, 1 are pre-attached is installed at the removal location as shown in FIG. 1(d). do.

When installing the precast concrete member 103a, as shown in FIG. 9(a), the connection units 1, 1 pre-attached to the precast concrete member are positioned at the width center of the notch 114 formed in the precast concrete member 103b. At this time, as shown in FIG. 10 , the lower connection unit 1 among the connection units 1 , 1 is lowered without colliding with the force distribution bar 167 a protruding into the notch 114 . It can smoothly pass through the arrangement space sandwiched between the protruding parts of the forceps and can be superimposed directly above the force distribution muscle 167b, and the upper connection unit 1 collides with the force distribution muscle 167a projecting into the notch 114. Consideration is given to the protruding length L of the force distribution bar 167a and whether or not post-cast concrete can be filled around the protrusion portion of the force distribution bar so as to enable smooth positioning in the arrangement space sandwiched between the protruding portions of the force distribution bar without Meanwhile, the width W _max of the notch 114, the width Sw of the stepped portion, and the depth Sd of the stepped portion are appropriately set.

Next, as shown in FIG. 11, concrete is placed in the notch 114, and the joining side of the precast concrete members 103a and 103b is removed except for an operation work area 131 for operating the female screw members 5a and 5b. Concrete is placed in the space extending to the end faces 115a and 115b.

It is desirable that the above-mentioned concrete that is cast as the post-cast concrete is cold-curing, ultra-high-strength fiber-reinforced concrete.

In this way, the notch 114 is provided with the tensile force transmission portion 113 so as to be continuously integrated with the precast concrete member 103b, and the anchor plate 3b is embedded in the tensile force transmission portion.

In addition, a joint portion 116 is provided in the space extending to the joint side end surfaces 115a and 115b of the precast concrete members 103a and 103b so as to be continuously integrated with the precast concrete members 103a and 103b.

Next, after the concrete strength of the tensile force transmission portion 113 and the joint portion 116 is developed, the female screw members 5a and 5b are operated so that the cylindrical reaction members 4a and 4b are released from the contracted state.

Specifically, as shown in FIG. 12(a), the female screw members 5a and 5b are rotated clockwise to bring the cylindrical reaction members 4a and 4b closer.

As already described, the annular sliding member 10 is constructed so that the side plates 12a, 12b and the central plate 11 of the annular sliding member 10 can slide. can be loosened smoothly.

When the female screw members 5a and 5b are operated in this manner, the compressive force generated in the cylindrical reaction members 4a and 4b and the tensile force of the PC steel bar 2 which is the reaction force are released. The tensile force of the PC steel material 2, as shown in FIG. The two precast concrete members 103a and 103b act on their joint side end faces 115a and 115b through the joint 116, respectively, and are balanced by the compression reaction forces received from the joint side end faces 115a and 115b of 103a and 103b. The tensile force of the PC steel materials 2 with the compressive force as the reaction force pulls them together and connects them.

The unboxed operation work area 131 may be appropriately filled with concrete or mortar after the tensile force is released.

As described above, according to the precast concrete member 103b according to the present embodiment, the joint side opening 161, the insertion side opening 163, and the non-insertion side opening 164 are formed on the joint side end surface 115b, the upper surface 162a, and the lower surface 162b. A notch 114 is provided for the insertion side opening 163, and the width W of the notch is maximized at the insertion side opening 163 (W _max ).
Since the notch 114 is formed so that it decreases discontinuously as it becomes deeper from the mouth and is minimized at the non-insertion side opening 164, the notch 114 has a width W at the insertion side opening 163 into which the connecting units 1, 1 are inserted. spread.

Therefore, when the precast concrete member 103b is lowered, the connection units 1, 1 attached to the precast concrete member in advance interfere with the force distributing bars 167a projecting from the opposing inner surfaces 166, 166 of the notch 114, and the lowering operation takes time. There is no need to worry that it will be difficult to hang down.

On the other hand, in arranging the connecting units 1, 1 in two stages, upper and lower, in the slit 114, in the lower stage, the force distributing bars 167a are divided and arranged in the slit 114 like the upper stage, and are sandwiched between their protruding ends. Instead of arranging them in a space, the force distributing bars 167b are arranged continuously in the slits 114 and arranged so as to overlap them. It becomes possible to narrow the width W of the notch 114 .

Therefore, the cross-sectional area of the notch 114 can be suppressed to the same extent as when the width is constant with respect to the depth, that is, when the cross section is rectangular. Therefore, the contact area between the tensile force transmission part 113 and the precast concrete member 103b is larger than when the cross section is rectangular, and therefore the length of the notch 114 required to secure the same contact area is increased. , the cutout 114 can be made shorter than in the case of a rectangular cross section, and thus the volume of the notch 114 and thus the amount of concrete used can be made smaller than in the case of a rectangular cross section.

Further, according to the precast concrete member 103b according to the present embodiment, the opposing inner surfaces 166, 166 of the notch 114 are stepped inner surfaces, respectively. and, as a result, the overall length of the notch 114 can be made shorter to use even less concrete.

In addition, since the stepped inner surface exerts a tenon action (dowel action), the continuous arrangement of the force distributing bars 167b within the slit 114 increases the shear resistance force, and the upper surface 162a and the lower surface 162b The resistance against external force in the direction perpendicular to the surface is also improved.

Further, according to the precast concrete member connection structure 104 according to the present embodiment, the fixing plate 3a attached to one end of the PC steel rod 2 is embedded in the precast concrete member 103a, and the fixing plate 3a is attached to the other end. The fixed plate 3b is embedded in the tensile force transmission portion 113 which is provided continuously and integrally with the precast concrete member 103b, and the tensile force of the PC steel rod 2 pulls the precast concrete members 103a and 103b toward each other. Compared to the conventional configuration in which the PC steel material had to be lengthened because it had to be inserted into two precast concrete members, it is possible to shorten the length of the PC steel material, and each work such as transportation, loading, and installation. In addition, the PC steel material does not need to be inserted into two precast concrete members at the construction site, so there is no need for a scaffold for the insertion work, and the tensile force of the PC steel bar 2 Since what is introduced in advance at a factory or the like can be released at the construction site, there is no need for a scaffold for releasing the tensile force, and there is no need to manage the tensile force or tension at the construction site.

Although the precast concrete members 103a and 103b are made of prestressed concrete in this embodiment, they may be made of reinforced concrete or fiber reinforced concrete instead.

Further, in the present embodiment, the joint 116 is interposed between the precast concrete members 103a and 103b. If the load transmission of the members 103a and 103b is ensured, these members may be omitted.

Further, in the present embodiment, each fixing means of the present invention is constituted by the single fixing plate 3a and the single fixing plate 3b like the single fixing plate 3a. It is permissible to configure each plate.

Further, in this embodiment, in the connection unit 1, the center plate 11 is attached to both sides of an appropriate base material with PTFE (polytetrafluorofluoroethylene) so that the contact surfaces between the center plate 11 and the side plates 12a and 12b are sliding surfaces. ethylene), and the side plates 12a and 12b are made of stainless steel plates, respectively. In addition to the combination of a steel plate and a steel plate coated with PTFE, there are other configurations such as a stainless steel plate and a steel plate coated with resin, steel plates coated with PTFE, steel plates coated with resin, and steel plates coated with a lubricant. It is possible. By appropriately selecting the shape and material of the female screw members 5a and 5b, even when the female screw members 5a and 5b are rotated, the frictional force generated at the opposing surfaces even when the opposing surfaces are in contact with each other. , the annular slide member 10 may be omitted if the rotation operation is not hindered.

In addition, in the present embodiment, it is assumed that when the female screw members 5a and 5b are rotated, a load is generated that causes the opposing ends 8a and 8b of the cylindrical reaction members 4a and 4b to laterally slip. The end guide member 6 may be omitted as long as there is no risk of lateral slip load.

In the present embodiment, the reaction force generating and releasing mechanism of the present invention is configured by the female screw members 5a and 5b each having a right-handed thread formed on the inner peripheral surface. Alternatively, one may be right-handed and the other left-handed.

Here, in the above modification in which one of the pair of female screw members is a right-handed screw and the other is a left-handed screw, the pair of female screw members do not rotate relative to each other when the reaction force is generated and released. A structure corresponding to an annular sliding member is not necessary, and as shown in FIG. 13, it can be replaced by a coupler 74 as a reaction force generation canceling mechanism in which a left-hand thread and a right-hand thread are formed at each end. be.

Further, in this embodiment, the connection unit 1 includes a PC steel bar 2, fixing plates 3a and 3b attached to each end of the PC steel bar 2, and a reaction force for introducing a tensile force to the PC steel bar 2. a pair of cylindrical reaction force members 4a and 4b as reaction force members arranged coaxially with the PC steel rod 2 in such a manner that the PC steel rod 2 is inserted so as to be transmitted to the vicinity of each end of the steel rod; A reaction force that can generate the above-mentioned reaction force by restraining the axial deformation of the tubular reaction force member in a contracted state, and release the reaction force by canceling the restraint state. The tension force of the PC steel rod 2 is released to the surrounding concrete through the bearing pressure of the fixing plates 3a and 3b by constructing it with the female screw members 5a and 5b as the generating and releasing mechanism. Instead of the connecting unit 1, as shown in FIG. 14, a cylindrical PC steel bar 81 and a reaction force for introducing tensile force to the cylindrical PC steel bar are transmitted near each end of the PC steel bar. A rod-shaped reaction force member 82 arranged coaxially with the PC steel rod in such a manner that it is inserted through the cylindrical PC steel rod, and restraining the axial deformation of the rod-shaped reaction force member in a contracted state Precast concrete using a connection unit 84 provided with a reaction force generation and release mechanism 83 that can generate the above-mentioned reaction force and release the reaction force by releasing the restrained state You may make it connect the members 103a and 103b.

In this modification, approximately half the length range (approximately the left half in FIG. 14) of the tubular PC steel bar 81 is the precast concrete member 103a, and the remaining length range (the same right half) is the precast concrete member 103b. The cylindrical PC steel rods 81 are embedded in the tensile force transmission parts 113 which are continuously and integrally provided, respectively, and release the tensile force of the cylindrical PC steel rod 81 to the surrounding concrete through adhesion on the peripheral surface thereof. A release mechanism 83 is provided at the other end of the cylindrical PC steel rod 81. Except for these points, the connection process is the same as when the connection unit 1 is used. omitted.

In addition, in the present embodiment, in addition to forming the opposing inner surfaces 166, 166 of the notch 114 in a stepped shape as a whole, the lower range includes slopes so that the width gradually narrows downward. However, instead of this, as shown in FIG. 15(a), by making the lower range an upright wall, the opposing inner surfaces 171, 171 forming a simple stepped inner surface as a whole can be formed. I don't mind.

In this embodiment, the insertion side opening 163 is provided in the upper surface 162a of the notch 114, and the non-insertion side opening 164 is provided in the lower surface 162b. For example, as shown in FIG. 15(b), the non-insertion side opening 164 may be omitted.

In addition, in the present embodiment, the opposed inner surfaces 166, 166 of the notch 114 are formed in a stepped shape as a whole. It suffices if it is formed so as to decrease continuously or discontinuously as it becomes larger.
The opposing inner surfaces 172, 172 may be configured such that the width W continuously decreases as the depth from the mouth 163 increases, that is, the opposing inner surfaces 172, 172 may be configured as slopes.

In the present embodiment, the opposed inner surfaces 166, 166 of the notch 114 are formed symmetrically about the width center, but instead of this, they can be formed asymmetrically.

[Second embodiment]
Next, a second embodiment will be described. Components that are substantially the same as those in the first embodiment are denoted by the same numbers, and descriptions thereof will be omitted.

16A and 16B are general views showing how the connection structure of precast concrete members according to the present invention is applied to a floor slab 141 of a bridge. It is an arrow view.

As shown in the figure, the floor slab 141 spans over the main girder 102 of the bridge in the form of rectangular precast concrete members 143a and 143b placed side by side in the direction perpendicular to the bridge axis. The precast concrete members 143a and 143b are connected to each other in the direction perpendicular to the bridge axis using a connecting structure 144 of the precast concrete members.

Here, as shown in FIG. 17, the precast concrete members 143a and 143b are connected in such a manner that the joint side end faces 115a and 115b are opposed to each other. , and detailed description thereof is omitted here.

For convenience of explanation, in the precast concrete members 143a and 143b, the cutouts 114 are called cutouts 114a and 114b, and the tensile force transmission portions 113 are called tensile force transmission portions 113a and 113b.

As shown in FIG. 17, the connecting structure 144 of the precast concrete member is provided in the notch 114a so that the fixing plate 3a attached to one end of the PC steel bar 2 is continuously integrated with the precast concrete member 143a. The fixing plate 3b attached to the other end of the tensile force transmitting portion 113a made of post-cast concrete is provided in the notch 114b so as to be continuously integrated with the precast concrete member 143b. A joint portion 116, which is also made of post-cast concrete, is provided between the joint side end surfaces 115a and 115b of the precast concrete members 143a and 143b, respectively, and is embedded in the transmission portion 113b. By balancing the tensile force of the PC steel rod 2 with the compressive force generated in the surrounding concrete through the precast concrete members 143a and 143b, the compressive reaction force is taken from the joint side end faces 115a and 115b of the precast concrete members 143a and 143b. The precast concrete members 143a, 143b are pulled together by a tensile force and connected.

As can be seen in FIG. 1B, the PC steel material 2 and the fixing plates 3a, 3b are arranged in two sets in two upper and lower stages along the thickness direction of the precast concrete members 143a, 143b.

The joint-side end surface 115a of the precast concrete member 143a is formed with a ridge in the width direction of the notch 114a so as to increase the bonding strength between the precast concrete member and the joint portion 116. The side end surface 115b is also formed with a ridge in the width direction of the notch 114b so as to increase the bonding strength between the precast concrete member and the joint 116. As shown in FIG.

The PC steel rod 2 and the fixing plates 3a and 3b are part of the elements constituting the connection unit 1, and other constituent elements belonging to the connection unit are also connected to the tensile force transmission portions 113a and 113b and the joint portion 116. Although embedded, such other constituent elements are omitted from FIG. 17 because they do not exhibit any particular action as a connecting structure.

Next, a case where the method of connecting the precast concrete members 143a and 143b using the connecting unit 1 is applied to bridge floor slab replacement will be described.

First, tensile force is introduced into the PC steel bar 2 by the same procedure as in the first embodiment.

Next, the two precast concrete members 143a and 143b are manufactured such that the notches 114a and 114b are formed in the two precast concrete members 143a and 143b, respectively. The precast concrete members 143a and 143b may be manufactured prior to the step of introducing tensile force to the PC steel rod 2, or may be performed simultaneously.

Next, the connection unit 1 and the precast concrete members 143a and 143b are transported to the bridge floor slab replacement site, which is the construction site.

Next, as described in FIG. 8 of the first embodiment, of the existing floor slabs 121a and 121b to be replaced, first only the existing floor slab 121b is removed, and a precast concrete member 143b is placed at the removed location. Then, the existing floor slab 121a is removed, and a precast concrete member 143a is installed at the removed location, thereby arranging the precast concrete members 143a and 143b side by side.

Next, the two connecting units 1, 1 are installed in two tiers so as to straddle the two precast concrete members 143a, 143b. At this time, as shown in FIG. The connection units 1, 1 are inserted so that the fixing plate 3a of the PC steel bar 2 is positioned in the notch 114a and the fixing plate 3b of the PC steel bar 2 is positioned in the notch 114b formed in the precast concrete member 143b. Deploy.

Here, regarding the width W _max of the cutouts 114a and 114b, the width Sw of the stepped portion, and the depth Sd of the stepped portion, as in the first embodiment, the lower connection unit 1 among the connection units 1 is It is possible to smoothly pass through the arrangement space sandwiched between the protruding portions of the force distribution muscles without colliding with the force distribution muscles 167a projecting into the cutouts 114a and 114b, and to overlap the force distribution muscles 167b directly above. so that the connection unit 1 can be smoothly positioned in the arrangement space sandwiched between the protruding portions of the force distribution muscles without colliding with the force distribution muscles 167a projecting into the notches 114a and 114b. Since the length L and whether or not post-cast concrete can be filled around the protruding portion of the force distributing bar are appropriately set, the connection units 1, 1 can be smoothly inserted and arranged.

Next, as shown in FIG. 19, concrete is placed in the cutouts 114a and 114b, and the precast concrete members 143a and 143b are removed except for an operation work area 151 for operating the female screw members 5a and 5b. Concrete is placed in the space extending to the joint side end surfaces 115a and 115b.

It is desirable that the above-mentioned concrete that is cast as the post-cast concrete is cold-curing, ultra-high-strength fiber-reinforced concrete.

In this way, the notch 114a is provided with the tensile force transmission portion 113a so as to be continuously integrated with the precast concrete member 143a, and the fixing plate 3a is embedded in the tensile force transmission portion. Similarly, the notch 114b is provided with a tensile force transmission portion 113b that is continuously integrated with the precast concrete member 143b, and the anchor plate 3b is embedded in the tensile force transmission portion.

In addition, a joint portion 116 is provided in the space extending to the joint side end surfaces 115a and 115b of the precast concrete members 143a and 143b so as to be continuously integrated with the precast concrete members 143a and 143b.

Next, after the concrete strength of the tensile force transmission portions 113a and 113b and the joint portion 116 is developed, the female screws are tightened so as to release the contracted state of the cylindrical reaction members 4a and 4b in the same manner as in the first embodiment. By operating the members 5a and 5b, the compressive force generated in the tubular reaction force members 4a and 4b and the tensile force of the PC steel bar 2, which was used as the reaction force, are released.

12(b), the tensile force of the released PC steel material 2 is balanced with the compressive force of the surrounding concrete through the bearing pressure of the fixing plates 3b and 3a. are balanced by compression reaction forces received from the joint side end surfaces 115a and 115b of the precast concrete members 143a and 143b, respectively, and thus the two precast concrete members 143a and 143b are connected to their joint sides via the joint 116. The tensile force of the PC steel material 2 in response to the compressive force acting on the end surfaces 115a and 115b pulls them together and connects them.

The unboxed operation work area 151 may be appropriately filled with concrete or mortar after the tensile force is released.

As described above, according to the precast concrete members 143a and 143b according to the present embodiment, the connection units 1 and 1 are inserted into the notches 114a and 114b, similar to the precast concrete member 103b described in the first embodiment. The width W is widened at the insertion side opening 163 .

Therefore, when the connecting units 1, 1 are lowered from the juxtaposed precast concrete members 143a, 143b, the connecting units interfere with the force distributing bars 167a protruding from the facing inner surfaces 166, 166 of the notches 114a, 114b. There is no fear that the work will take time or that the hanging down itself will be difficult.

On the other hand, in arranging the connecting units 1, 1 in two stages, upper and lower, in the slits 114a, 114b, for the lower stage, the force distributing bars 167a are divided and arranged in the slits 114a, 114b as in the upper stage, and are attached to the projecting ends thereof. Since the force distributing bars 167b are arranged continuously in the slits 114a and 114b and overlapped with each other instead of being arranged in the sandwiched arrangement space, it is unnecessary to secure the projecting length L due to the divided arrangement. , the width W of the notches 114a and 114b in the lower range can be narrowed.

Therefore, the cross-sectional areas of the cutouts 114a and 114b can be suppressed to the same degree as in the case where the width is constant with respect to the depth, that is, the cross section is rectangular. 166 is not upright, the contact area between the tensile force transmitting parts 113a, 113b and the precast concrete members 143a, 143b is greater than in the case of a rectangular cross-section, and therefore the contact area is required to ensure an equivalent contact area. The length of the cutouts 114a and 114b can be made shorter than in the case of a rectangular cross section, and thus the volume of the cutouts 114a and 114b and thus the amount of concrete used can be made smaller than in the case of a rectangular cross section. Become.

Since the effects of the cutouts 114a and 114b are the same as those of the cutout 114 described in the first embodiment, description thereof will be omitted here.

Further, the effect of the precast concrete member connection structure 144 according to the second embodiment is substantially the same as the effect of the first embodiment, and the modified example described in the first embodiment is the same as the second embodiment. Although applicable to the embodiments as well, their details are omitted to avoid duplication.

1 Connection unit 2 PC steel bar (PC steel material)
3a, 3b fixing plate (fixing means)
4a, 4b Cylindrical reaction force members 5a, 5b Female screw member (reaction force generation and release mechanism)
74 coupler (reaction force generation release mechanism)
84 Connection units 103a, 103b Precast concrete member 104 Connection structure of precast concrete member 113 Tensile force transmission part 114 Notch 115a, 115b Joint side end face 143a, 143b Precast concrete member 113a, 11b Tensile force transmission part 114a, 114b Notch 144 Precast Concrete member connection structure 161 Joining side opening 162a Upper surface (one non-joining surface)
163 insertion side opening 164 non-insertion side openings 166, 166 opposing inner surface 167a distributing bar (first distributing bar)
167b Distributing muscle (second distributing muscle)
168a main reinforcing bar (first main reinforcing bar)
168b main reinforcing bar (second main reinforcing bar)
171, 171 Opposing inner surfaces 172, 172 Opposing inner surfaces

Claims (6)

A joining-side opening is provided on the joining-side end surface, and an insertion-side opening is provided on one non-joining surface of a pair of non-joining surfaces extending in the orthogonal direction so as to be back-to-back from the joining-side end surface. A notch is provided, and a tensile force transmission part made of post-cast concrete is embedded in the notch, and a predetermined range including the end of the PC steel material is embedded in the post-cast concrete, or a fixing means attached to the end is embedded. A precast concrete member that can be installed in a
The facing inner surface distance of the notch along the direction parallel to the pair of non-joint surfaces and parallel to the joint-side end surface is maximum at the insertion-side opening, and continuously or discontinuously as it becomes deeper from the insertion-side opening. A precast concrete member, wherein the cutout is formed so as to decrease continuously. 2. A precast concrete member according to claim 1, wherein the opposing inner surfaces of said notches are stepped inner surfaces. Reinforcing bars parallel to the pair of non-joining surfaces and parallel to the joining side end face are arranged in two stages, and the reinforcing bars on the side closer to the insertion side opening are the first distributing bars and the insertion side. The reinforcing bar on the far side from the opening is used as a second force distributing bar, and the reinforcing bar along the direction perpendicular to the joint side end surface is arranged in two stages, and the reinforcing bar on the side closer to the insertion side opening is used as the first distributing bar. The main reinforcing bars and the reinforcing bars on the far side from the insertion side opening are used as second main reinforcing bars, and the first force distributing bars are divided and arranged so that the portions extending from the opposing inner surfaces of the cutouts are projecting ends and are spaced apart from each other. 3. The precast concrete member according to claim 1, wherein the second force distributing reinforcement is continuously arranged so as to extend from one side to the other side of the opposing inner surfaces of the notch. 4. The precast concrete member according to any one of claims 1 to 3, which is made of prestressed concrete. 5. The first precast concrete member and the second precast concrete member juxtaposed so that the joint side end face and the joint side end face of the first precast concrete member are opposed to each other according to any one of claims 1 to 4 A predetermined range including the precast concrete member described above, a tensile force transmission portion provided in the notch with post-cast concrete so as to be continuously integrated with the second precast concrete member, and one end portion, or the one is embedded in the first precast concrete member, and the remaining range including the other end or the anchoring means attached to the other end is attached to the tensile force transmission part A tensile force of the prestressed concrete steel material that is embedded and the compressive force acting on the joint side end face of the first precast concrete member and the second precast concrete member is a reaction force. A connecting structure of precast concrete members drawn together by a. The precast concrete member according to any one of claims 1 to 4 as a third precast concrete member, and a third precast concrete member juxtaposed so that the joint side end surface and the joint side end surface of the third precast concrete member face each other. 4. The precast concrete member according to any one of claims 1 to 4 as the precast concrete member of 4, and the third precast concrete member and the fourth precast concrete member so as to be continuous and integral with each. Two tensile force transmission portions respectively provided with post-cast concrete in the notches belonging to the respective precast concrete members, and among the tensile force transmission portions, the tensile force transmission portions belonging to the third precast concrete member. A predetermined range including one end, or the rest of the range including the other end in the tensile force transmission part belonging to the fourth precast concrete member, or the anchoring means attached to the one end is embedded, or PC steel material in which the fixing means attached to the other end is embedded, and the third precast concrete member and the fourth precast concrete member are compressed by mutually acting on their joining side end faces. A connecting structure of precast concrete members, characterized in that the precast concrete members are pulled together by the tensile force of the PC steel materials with the force acting as the reaction force.

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