JP7502585B2 - Bridge deck joints - Google Patents

Description

The present invention relates to joints for joining multiple bridge decks.

2. Description of the Related Art In conventional bridges, decks are joined together. For example, a method using loop reinforcing bars is known as a method for joining precast decks of a bridge (see, for example, Patent Document 1).
Also known is a method of joining deck slabs by providing a convex or concave portion on the surface where the deck slabs are joined and positioning the convex portion of one deck slab within the concave portion of the other deck slab (see, for example, Patent Document 2).
Also, as a method of joining other components together, a so-called cotter joint is known in which a C-type coupling fitting is protruded from each side surface of a pair of components and the fitting portion of an H-type coupling fitting is positioned within a mating recess of the C-type coupling fitting (see, for example, Patent Document 3).

JP 2008-303538 A Patent No. 5879452 Patent No. 5787965

However, the method described in the above-mentioned Patent Document 1 requires bending the rebar on-site, inserting a wire through the loop of the rebar, and then pouring the concrete, which means that the installation work of the precast deck requires a long time. In addition, since the inner bending radius of the loop shape of the rebar is determined to a certain extent, the thickness of the precast deck cannot be made thin, making it impossible to apply to a specified planned height, and the weight of the precast deck increases, which increases the reaction force and stress, which is structurally disadvantageous to the substructure, etc.

In addition, in the method described in Patent Document 2, the components are attached to each other via a filler, but no steel rods or prestress are used to apply stress to the deck in the bridge axis direction. This means that gaps may appear between the decks due to expansion and contraction of the decks caused by temperature changes, and there is a risk that the decks may shift in position in a direction perpendicular to the bridge axis, making it impossible to maintain the joint.

In addition, in the method described in Patent Document 3, when a pair of members are arranged in a predetermined position, the fitting portion of the H-type joint fitting can be fitted into the fitting recess of each C-type joint fitting, and only then can the C-type joint fitting and the H-type joint fitting be fixed with a bolt. Therefore, if the members are out of the predetermined position, there is a problem that the fitting portion of the H-type joint fitting cannot be fitted into the fitting recess of both C-type joint fittings and fixed with a bolt. In addition, in the cotter joint described in Patent Document 3, since the members cannot be positioned by fitting the H-type joint fitting to the C-type joint fitting, it is necessary to perform positioning work of the members without error when joining the members. In addition, when the members are precast decks used for bridges, it is very difficult to adjust the posture of the members by hanging multiple chain blocks on the precast deck, such as aligning them in the direction along the bridge axis, the direction perpendicular to the bridge axis, and the height direction, and correcting the inclination with respect to the bridge surface, which increases the work time and greatly reduces workability.
In addition, if the positioning of the components is performed using the fastening force of the bolts fastening both fittings of the H-type joint fitting and the C-type joint fitting, that is, when the positions of the components are slightly misaligned and the fittings of the H-type joint fitting are halfway into the fitting recesses of the C-type joint fitting, and the H-type joint fitting is forcibly fastened with the axial force of the bolts so that the fittings fit into the fitting recesses, the bolts cannot be fastened accurately. In other words, it is extremely difficult to simultaneously fasten each bolt at the same speed (or torque), and in practice, each side is gradually fastened one by one. However, this task is not easy and is greatly influenced by the sense and skill of the worker, and there is a problem that the fastening state varies depending on the worker. Specifically, when the bolts are fastened one by one, the H-type joint fitting will sink on the fastened side and appear to be relatively raised on the opposite side, resulting in an inclination. As a result, the H-joint fitting may end up being fixed in a different position and at an angle, rather than in the position in which it should be. This not only causes abnormalities in the fastening force, but also reduces fatigue strength and can cause unintended problems with the joint compression force. As can be seen from this, it is desirable for the H-joint fitting to always be installed and fixed so that its horizontal position is not tilted.

The present invention was developed through intensive research by the inventor in consideration of the above problems, and aims to provide a means of improving workability, including relative positioning, when joining bridge decks using a simple structure.

The bridge deck joint of the present invention is a bridge deck joint comprising a pair of inserted parts provided on a pair of adjacent decks of a bridge, a pair of engaging parts that can be inserted into the inserted parts, and a connecting member having a bridging part connecting the pair of engaging parts, the bridging part having a hole that penetrates along the insertion direction of the engaging parts, a shaft part that is inserted into the hole, and a contact body that can rotate with the shaft part, the contact body rotates with the shaft part to a predetermined angle, and then engages with the inserted part in the circumferential direction to restrict rotation, and a positioning mechanism is formed between the inserted part and the engaging part so that the engaging part is positioned relative to the inserted part when the engaging part is inserted into the inserted part.

The bridge deck joint of the present invention is also characterized in that the positioning mechanism has an abutment surface on the outer peripheral surface of the engagement portion and/or the inner peripheral surface of the inserted portion that can generate a pressing force on the inserted portion in a direction perpendicular to the insertion direction.

The bridge deck joint of the present invention is characterized in that the shaft portion has a male threaded portion, and has a head fixed to one side and a contact body screwed to the other side of the bridging portion of the shaft portion, or has a female threaded body screwed to one side and a contact body fixed to the other side, and the inserted portion and the bridging portion are sandwiched axially between the head or female threaded body and the contact body by rotation of the head or female threaded body.

The bridge deck joint of the present invention is also characterized by having a fixing part that fixes the engaging part and the inserted part.

The bridge deck joint of the present invention is characterized in that the fixing portion is a male threaded body, the engaging portion has a hole through which the male threaded body is inserted, and the inserted portion has a female threaded hole that can be screwed into the male threaded body.

The present invention provides a simple structure that can improve workability, including the relative positioning when joining bridge decks.

FIG. 2 is a plan view showing a precast floor slab to which the joint according to the first embodiment is applied. FIG. 2 is a cross-sectional view of a precast deck to which a joint according to the first embodiment is applied. 1A is a perspective view of a receiving member of a joint according to a first embodiment, FIG. 1B is a cross-sectional view seen from the left side, and FIG. 1C is a cross-sectional view seen from the front. FIG. 2 is a perspective view showing a connecting member of the joint according to the first embodiment. 11A to 11C are diagrams showing a procedure for connecting the receiving members to each other with the connecting member. 1A to 1C are diagrams showing the positioning process of a precast deck to which a joint according to the first embodiment is applied. FIG. 13 shows positioning of precast deck slabs by spacing them apart. FIG. 13 is a diagram showing positioning when the precast deck is misaligned in the Y direction. 13 is a cross-sectional view showing a state in which the engagement portion abuts against one inner circumferential surface in the Y direction. FIG. 13A and 13B are diagrams illustrating an example of an anti-rotation mechanism between a shaft portion and a bridge portion. 13A and 13B are diagrams showing other shapes of the inner circumferential surface of the accommodating portion and the outer circumferential surface of the engaging portion. 11A and 11B are diagrams illustrating examples of inclination of the inner circumferential surface of the storage portion. 10A and 10B show a joint according to a second embodiment, in which FIG. FIG. 11 is a perspective view showing a receiving member of a joint according to a second embodiment. 11A and 11B are diagrams illustrating examples of shapes of a concave-convex engagement portion. 11A and 11B are cross-sectional views showing the configuration of another connecting member. 1A and 1B are diagrams showing a provisionally assembled state and an actually assembled state of a joint; 13A to 13C are diagrams showing a procedure for applying prestress by rearranging connecting members. FIG. 11 is a cross-sectional view showing the configuration of another joint. FIG. 11 is a plan view showing another example of the arrangement of precast floor slabs. FIG. 11 is a plan view showing another receiving member. FIG. 11 is a perspective view showing the configuration of another joint. 1A and 1B show a connecting member, in which FIG. FIG. 13 is a diagram showing the orientation of the connecting member when the receiving member is shifted in the Y direction. FIG. FIG. 13 is a diagram showing another configuration of the joint. 13A and 13B are diagrams showing connection between receiving members having different heights. FIG. 13 is a diagram showing another configuration of the joint. FIG. 13 is a diagram showing another configuration of the joint. FIG. 13 is a diagram showing another configuration of the joint.

Below, an embodiment of the bridge deck joint of the present invention will be described using an example in which it is applied to precast decks used in decks such as bridges, roads, or railway track foundations.

Figure 1 is a plan view showing a precast deck 1 to which a joint 10 according to the first embodiment is applied, and Figure 2 is a cross-sectional view of the precast deck 1 to which a joint 10 according to the first embodiment is applied, taken along line A-A in Figure 1. The precast deck 1 is fixed across a number of main girders (not shown) arranged in the bridge width direction (Y direction). The precast decks 1 are also arranged adjacent to each other along the bridge axis direction (X direction) as the member connection direction, and the opposing precast decks 1, 1 are connected by joints 10. After the precast decks 1, 1 are connected by joints 10, a hardening fluid such as grout material, ready-mixed concrete, water glass, or a thermosetting or thermoplastic synthetic resin in a fluid state may be injected between the precast decks 1, 1 to seal the joints.

The joint 10 has a connecting member 20 and receiving members 30 and 30a, and is configured by connecting the receiving members 30 and 30a to each other with the connecting member 20. FIG. 3 is a perspective view showing the connecting member 20 of the joint 10 according to the first embodiment. The connecting member 20 has a generally H-shaped cross section and has a pair of engaging portions 22, a bridging portion 24 connecting the pair of engaging portions 22, a shaft portion 26 inserted into the bridging portion 24, and a pressing body (contact body) 28 supported so as to rotate integrally with the shaft portion 26.

The engaging portion 22 is a member extending in a direction perpendicular to the XY plane, has a tapered outer circumferential surface, and is generally a quadrangular pyramid shape that gradually narrows from the base end (upper end) side fixed to the bridging portion 24 to the tip end (lower end). That is, the outer circumferential surface of the engaging portion 22 that faces in the X direction is inclined generally symmetrically from the upper end to the lower end so as to narrow the distance in the X direction, and the outer circumferential surface that faces in the Y direction is inclined generally symmetrically from the upper end to the lower end so as to narrow the distance in the Y direction.

The bridging portion 24 is formed in a narrow shape with a shorter length in the Y direction than the engaging portion 22. The center of the bridging portion 24 in the XY plane has an insertion hole that extends in a direction perpendicular to the XY plane, and the shaft portion 26 is inserted into the insertion hole. The shaft portion 26 has a male threaded portion 26a with a right-handed male threaded spiral groove formed at one end. The shaft portion 26 also has a head portion 26b at the other end, which has an outer periphery larger than the insertion hole of the bridging portion 24 and has a hexagonal hole formed in the top surface. The head portion 26b has a seat that can come into contact with the bridging portion 24.

The pressing body 28 has a generally rectangular shape in plan view with a short side portion 28a and a long side portion 28b, and has a female threaded hole that can be screwed into the male threaded portion 26a.

The short side portion 28a is set to a length that does not interfere with the receiving members 30, 30a when the connecting member 20 is disposed between the receiving members 30, 30a. In other words, the short side portion 28a is set to a length that is shorter than the distance between the receiving members 30, 30a.

The long side portion 28b is set to a length that interferes with the receiving members 30, 30a when the connecting member 20 is disposed between the receiving members 30, 30a. In other words, the long side portion 28b is set to a length that exceeds the distance between the receiving members 30, 30a.

4 shows the receiving members 30, 30a of the joint 10 according to the first embodiment, where (a) is a perspective view, (b) is a cross-sectional view seen from the left side when the end face side of the precast floor slab 1 is the front side, and (c) is a cross-sectional view seen from the front side. The receiving members (inserted parts) 30, 30a are C-shaped joint fittings of the same shape, and are respectively disposed at the ends of a pair of opposing precast floor slabs 1, 1. A part of the receiving members 30, 30a is embedded in the end of each precast floor slab 1, 1 extending along the Y direction. Therefore, the precast floor slabs 1, 1 are disposed so that the receiving members 30, 30a face each other along the X direction.
Although the receiving members 30, 30a are each considered to be a C-shaped joint fitting, it is sufficient that they have the strength required for a joint, and the material is not limited to metal.

The receiving members 30, 30a have an anchor portion 32 that extends in the X direction within the precast deck 1, a recessed accommodation portion 34 into which the engagement portion 22 of the connecting member 20 can be fitted, a restricting portion 36 against which the long side portion 28b of the pressing body 28 can abut, and a step portion 38 that faces the restricting portion 36 in the Y direction.

The receiving members 30, 30a are disposed on the precast deck 1 with the opening edge of the storage section 34 facing upward and oriented along the XY plane. Note that the opening edge of the storage section 34 is not necessarily limited to being disposed facing upward, and the orientation can be set as appropriate, such as facing downward.
In addition, the receiving members 30, 30a may be arranged so that the storage portion 34 protrudes from the end of the precast deck 1, or part of the storage portion 34 may be embedded within the precast deck 1, and the arrangement method can be set as appropriate.

The accommodation portion 34 has a notch at the end opposite the anchor portion 32 in the X direction into which the bridge portion 24 can be fitted, and has a lip portion 34a along the edge of the notch. The lip portion 34a engages with the engagement portion 22 in the X direction.

The inner peripheral shape of the storage section 34 corresponds roughly to the outer shape of the engagement section 22, and is roughly a quadrangular pyramid shape that gradually narrows from the opening edge to the bottom. That is, as shown in FIG. 4(b), the inner peripheral surfaces 40a, 40b facing in the X direction of the inner peripheral surfaces of the storage section 34 are inclined roughly symmetrically from the opening edge along the bottom toward the center in the X direction. Also, as shown in FIG. 4(c), the inner peripheral surfaces 40c, 40d facing in the Y direction are inclined roughly symmetrically from the opening edge along the bottom toward the center in the Y direction.

The restricting portion 36 is formed at a position where it can abut against the long side portion 28b of the pressing body 28, approximately directly below the storage portion 34. That is, it extends in a perpendicular direction from the lower end surface 34b of the storage portion 34, and when the lip portion 34a side of the storage portion 34 shown in FIG. 4(a) is the front side, the restricting portion 36 is formed on the lower right side of the storage portion 34. The space defined by the lower end surface 34b and the restricting portion 36 functions as a space where the long side portion 28b of the pressing body 28 can enter and abut against the restricting portion 36.

Next, the procedure for connecting the support members 30, 30a with the connecting member 20 and connecting the precast floor slabs 1 will be described. The precast floor slabs 1 are arranged with the ends on which the support members 30, 30a are arranged facing each other. The support members 30, 30a are also arranged at a predetermined distance so that the lip portions 34a of each other face each other.

The connecting member 20 has each engagement portion 22 fitted into each storage portion 34 in a direction perpendicular to the XY plane, i.e., in the direction indicated by arrow A in FIG. 5(a). As a result, the engagement portion 22 fits into the inner peripheral surface of each storage portion 34, and the connecting member 20 is disposed between the receiving members 30, 30a. Here, the pressing body 28 is positioned such that the short side portion 28a is parallel to the X direction and at the tip side of the shaft portion 26 so as not to interfere with the receiving members 30, 30a.

When the engagement portion 22 is fitted into the storage portion 34, the pressing body 28 is positioned between the receiving members 30, 30a so that it can enter the space defined by the lower end surface 34b of the storage portion 34 and the restricting portion 36. Therefore, when the shaft portion 26 is rotated approximately 90°, the pressing body 28 is positioned between the receiving members 30, 30a so that the long side portion 28b can abut against the restricting portion 36.

Next, as shown in FIG. 5(b), when torque is applied in the fastening direction to the hexagonal hole of the head 26b using a tool such as a wrench, the pressing body 28 screwed onto the shaft 26 rotates together with the shaft 26. When the pressing body 28 rotates approximately 90° (a specified angle) and the long side portion 28b becomes parallel to the X direction, the long side portion 28b abuts against the restricting portion 36 of each receiving member 30, 30a, and further rotation is restricted. In this way, after rotating the specified angle together with the shaft 26, the pressing body 28 engages with the restricting portion 36 in the circumferential direction and rotation is restricted.

Furthermore, when torque is applied in the tightening direction, the shaft portion 26 rotates relative to the pressing body 28. As a result, the pressing body 28 rises (displaces) along the axial direction to a position where it abuts against the lower end surface 34b. That is, the pressing body 28 moves along the axial direction toward the receiving members 30, 30a and the bridging portion 24 as the shaft portion 26 rotates while abutting against the restricting portion 36, and abuts against the lower end surface 34b.

When the pressing body 28 abuts against the lower end surface 34b as shown in FIG. 5(c) and cannot rise, the rotation of the shaft portion 26 in the fastening direction is restricted and fastening is completed. As a result, the receiving members 30, 30a are connected by the connecting member 20, and the precast deck 1 is connected.

Next, we will explain the positioning function of the precast floor slab 1 based on the shapes of the storage portion 34 and the engagement portion 22. The joint 10 has a positioning function that moves the precast floor slab 1 by fitting the engagement portion 22 into the storage portion 34. Specifically, the engagement portion 22 and the storage portion 34 abut on their inclined surfaces, and the outer peripheral surface of the engagement portion 22 presses against the inner peripheral surface of the storage portion 34, thereby moving the precast floor slab 1.

When connecting precast floor slabs 1, 1, one precast floor slab 1 is fixed at a predetermined position, and the other precast floor slab 1 is moved to position them so that their relative positions are within a predetermined range (predetermined position). Here, the precast floor slab 1 with the receiving member 30a is fixed, and the precast floor slab 1 with the receiving member 30 is moved.

When the relative positions of the precast decks 1, 1 are spaced apart in the X direction by more than a predetermined distance, when the connecting member 20 is placed between the receiving members 30, 30a, the engaging portion 22 is locked at a mid-way position within the storage portion 34 as shown in FIG. 6(a). In other words, one of the inner peripheral surfaces 40a of the storage portion 34 and the outer peripheral surface of the engaging portion 22 are both inclined, and the tip of the outer peripheral surface of the engaging portion 22 abuts against the inner peripheral surface 40a at a mid-way position, restricting insertion into the bottom side of the storage portion 34.

When the head 26b is rotated in the fastening direction, the pressing body 28 gradually moves as described above and is displaced to a position where it abuts against the lower end surface 34b. Then, as shown in FIG. 6(b), the receiving member 30 and the connecting member 20 are sandwiched and pressed between the head 26b and the pressing body 28. Therefore, when the shaft 26 is further rotated in the fastening direction, the position of the pressing body 28 is restricted by the lower end surface 34b, so the head 26b presses the connecting member 20 toward the pressing body 28.

In addition, since the outer peripheral surface and inner peripheral surface 40a of the engagement portion 22 are in contact with each other at inclined surfaces, the pressing force of the head 26b pressing the connecting member 20 is transmitted to the inner peripheral surface 40a via the outer peripheral surface of the engagement portion 22 and converted into a force pressing the receiving member 30 in the X direction. Therefore, the receiving member 30 moves toward the receiving member 30a along the X direction together with the precast deck 1, and as a result of this movement, the engagement portion 22 enters the storage portion 34.

As described above, the receiving member 30 and the precast deck 1 on which the receiving member 30 is arranged gradually move toward the receiving member 30a (the other precast deck 1) along the X direction, and when the engaging portion 22 is inserted into the innermost portion of the storage portion 34, the relative position of the receiving member 30 to the receiving member 30a becomes a predetermined position, thereby positioning the precast decks 1, 1.

In this way, by rotating the shaft portion 26 in the fastening direction and fitting each engagement portion 22 of the connecting member 20 into each storage portion 34 of the receiving members 30, 30a, the engagement portion 22 presses against the inner surface of the storage portion 34, and the relative positions of the precast deck slabs 1, 1 can be positioned in a predetermined arrangement.

In the above description, the precast floor slabs 1, 1 whose relative positions are separated or shifted in the X direction by more than a predetermined distance are positioned and fixed in a predetermined arrangement, but the precast floor slab 1 whose relative positions are closer to each other in the X direction than the predetermined position can be moved to a predetermined position in the same way. That is, when the tip of the engagement portion 22 abuts on the other inner surface 40b of the storage portion 34 at a midpoint as shown in FIG. 7(a), if the head portion 26b is rotated in the fastening direction, the pressing body 28 abuts on the lower end surface 34b as shown in FIG. 7(b), and the receiving member 30 and the connecting member 20 are sandwiched between the head portion 26b and the pressing body 28.

As a result, the receiving member 30 is pressed in the X direction via the inner peripheral surface 40b that abuts the outer peripheral surface of the connecting member 20 in the direction away from the other precast deck 1, and the precast deck 1 and receiving member 30 move in the X direction away from the receiving member 30a. In addition, as the receiving member 30 moves, the engaging portion 22 enters the storage portion 34, and when the receiving member 30 moves to a predetermined position relative to the receiving member 30a, the engaging portion 22 fits into the storage portion 34, and the relative positions of the precast decks 1, 1 are positioned in a predetermined arrangement.

For example, when the precast decks 1, 1 are offset from each other in the Y direction as shown in FIG. 8(a), when the connecting member 20 is placed between the receiving members 30, 30a, the tip of the engaging portion 22 abuts against the inner circumferential surface 40c of the storage portion 34 and is locked in the middle position. In other words, the tip of the engaging portion 22 abuts against the inner circumferential surface 40c in the middle position, restricting it from fitting into the bottom side of the storage portion 34.

Here, FIG. 9 is a cross-sectional view taken in a direction perpendicular to the XY plane, showing the state in which the engaging portion 22 abuts against the inner peripheral surface 40c. When the engaging portion 22 abuts against the inner peripheral surface 40c at a midpoint and the head portion 26b rotates in the fastening direction, the pressing body 28 moves to a position where it abuts against the lower end surface 34b, as described above. The receiving member 30 and the connecting member 20 are then sandwiched and pressed between the head portion 26b and the pressing body 28.

In addition, since the outer peripheral surface and the inner peripheral surface 40c of the engagement portion 22 are inclined relative to each other, part of the pressing force applied to the receiving member 30 acts as a force in the Y direction via the inner peripheral surface 40c. Therefore, the receiving member 30 is pressed in the Y direction.

Therefore, each time the shaft portion 26 is rotated in the fastening direction, the precast deck 1 and the receiving member 30 gradually move in the Y direction, and as a result, the receiving member 30 is displaced to a predetermined position facing the receiving member 30a in the X direction.

In this way, even if the precast decks 1, 1 are misaligned in the X and/or Y directions, by connecting the receiving members 30, 30a with the connecting member 20, the precast deck 1 can be moved in the X and/or Y directions together with the receiving member 30 and positioned at a predetermined position. That is, the inner surface of the receiving portion 34 of the receiving member 30 is pressed by the engaging portion 22, and the precast deck 1 can be moved together with the receiving member 30 in the X and/or Y directions toward a predetermined position.

In addition, when the precast floor slabs 1, 1 are misaligned in the height direction perpendicular to the XY direction, the height positions of the precast floor slabs 1, 1 can be aligned by fitting the engagement portion 22 into the accommodation portion 34 of the receiving members 30, 30a and rotating the shaft portion 26 in the fastening direction. That is, the axial force acting on the shaft portion 26 when the shaft portion 26 is rotated in the fastening direction is transmitted to the connecting member 20 via the head portion 26b, or to the pressing body 28. Then, the connecting member 20 presses the receiving member 30, or the pressing body 28 presses the lower end surface 34b of the receiving member 30, and the precast floor slab 1 moves toward a predetermined height position together with the receiving member 30. This allows the precast floor slabs 1, 1 to be connected by aligning the height positions of the receiving member 30 and the receiving member 30a.
Of course, when the relative positions of the precast deck slabs 1, 1 are within a specified range, the engagement portion 22 can be inserted almost to the deepest part of the storage portion 34 without performing positioning work by rotating the above-mentioned shaft portion 26, so no positioning work is required.

As described above, with the joint 10 of this embodiment, even if the relative positions of the precast deck slabs 1, 1 are shifted from the predetermined position in the X direction, Y direction, or direction perpendicular to the XY plane (height direction) by significantly exceeding the intersection level (for example, by about several tens of mm), the relative positions of the precast deck slabs 1, 1 can be positioned so that they fall within a predetermined range by simply applying a pressing force to the connecting member 20 to enter between the receiving portions 30, 30a so as to fit the engaging portion 22 into the storage portion 34 of the receiving portions 30, 30a. This makes it easier to perform work including relative positioning when joining the precast decks 1, 1, and also shortens the work time, improving workability.
Furthermore, by simply fastening the receiving portions 30, 30a and the connecting member 20 between the head 26b and the pressing body 28, the head 26b presses the connecting member 20 (or the pressing body 28 presses the receiving portion 30), and the receiving portion 30 can be pressed in the X direction, Y direction and/or height direction.
In other words, by simply rotating the shaft portion 26 in the fastening direction so as to fasten the receiving portions 30, 30a and the connecting member 20 between the head 26b and the pressing body 28, the relative positions of the precast deck slabs 1, 1 can be positioned within a specified range, and by this series of operations, the connection work of the precast decks can finally be completed at an appropriate position, thereby further improving workability.

In addition, the pair of receiving members 30, 30a and the connecting member 20 are fastened together by a single shaft 26 that is inserted into the bridging portion 24 and a pressing body 28 that is disposed at the tip side of this shaft 26, so that the pair of receiving members 30, 30a and the connecting member 20 can be firmly fixed together. In addition, the connection between the pair of receiving members 30, 30a can be strengthened. Therefore, according to the present invention, the workability when connecting the receiving members 30, 30a can be improved.

In addition, by simply rotating the single shaft 26 inserted through the center of the bridge in the fastening direction, the pair of receiving members 30, 30a and the connecting member 20 are fastened and fixed, so that the engaging portion 22 enters and is fixed into the receiving portion 34 while the connecting member 20 remains horizontal, allowing the connecting member 20 and the receiving members 30, 30a to be fixed in an extremely stable manner.

In addition, even if the relative positions of the opposing precast decks 1, 1 are misaligned in the bridge axis direction or perpendicular to the bridge axis, the precast deck 1 and receiving member 30 can be moved to a specified position by fitting the engagement portion 22 into the storage portion 34, making positioning easy and further improving workability.

In addition to the above-mentioned configuration, the shaft portion 26 may be provided with a rotation prevention mechanism to prevent the shaft portion 26 from rotating in the loosening direction due to vibration or the like after fastening. Specifically, as shown in FIG. 10, a head side unevenness 50 is provided on the seat surface of the head portion 26b, and a bridge portion side unevenness 52 that can engage with the head side unevenness 50 is provided on the surface of the bridge portion 24. In addition, both unevennesses are formed in a sawtooth shape so that they can engage in the circumferential direction. That is, when the shaft portion 26 tries to rotate in the fastening direction, the head side unevenness 50 abuts on both inclined surfaces 50a, 52a, allowing relative sliding while increasing the distance between the two in the axial direction. On the other hand, when the shaft portion 26 tries to rotate in the loosening direction, the vertical surfaces (surfaces with a stronger inclination) 50b, 52b of each other abut against each other to prevent the shaft portion 26 from rotating.
Of course, the bridge portion unevenness 52 on the bridge portion 24 side corresponding to the head side unevenness 50 provided on the seat surface of the head portion 26 b may be configured as a washer-like member separate from the bridge portion 24 .

By forming such a rotation prevention mechanism, it is possible to prevent the shaft portion 26 from rotating in the loosening direction due to repeated vibration, and it is also possible to prevent the pressing body 28 from coming off and falling off due to the shaft portion 26 rotating in the loosening direction.

In addition, the internal space of the accommodation portion 34 and the shape of the engagement portion 22 have been described as being substantially quadrangular pyramid-shaped, but are not limited thereto. For example, the general shape of the engagement portion 22 may be substantially polygonal pyramid-shaped, such as substantially triangular pyramid-shaped, substantially pentagonal pyramid-shaped, substantially hexagonal pyramid-shaped, or substantially conical-shaped as shown in FIG. 11.
Similarly, the internal space of the accommodating portion 34 may be substantially polygonal, such as substantially triangular, pentagonal or hexagonal, or may be substantially conical in shape corresponding to the conical engagement portion 22 as shown in FIG.

In addition, the inner circumferential surface of the storage portion 34 and the outer circumferential surface of the engagement portion 22 have been described as being inclined symmetrically with respect to the surfaces facing each other in the X direction or Y direction, but of course this is not limited to this and they may be inclined asymmetrically, or one of the facing surfaces may be inclined and the other may not be inclined.

For example, of the inner circumferential surfaces 40a, 40b of the storage section 34, one of the inner circumferential surfaces 40a may not be inclined, and only the other inner circumferential surface 40b may be inclined, as shown in FIG. 12(a). Also, only one of the inner circumferential surfaces 40a may be inclined, as shown in FIG. 12(b), or the inner circumferential surfaces 40a, 40b may be inclined in the same direction with different inclination angles, as shown in FIG. 12(c) or FIG. 12(d). Of course, the inclination of the outer circumferential surface of the engagement section 22 may be set in the same manner as above.

In addition, the head 26b has a shape with a hexagonal hole on the top surface, but is not limited to this and may be a cross hole, a slot, a rectangular hole, a star-shaped hole, etc. Also, instead of providing a hole on the top surface, the outer shape may be an irregular shape such as an approximately square shape or an approximately hexagonal shape.

The precast floor slabs 1, 1 connected by the joints 10 are not limited to being arranged facing each other at a distance, but may be arranged in contact with each other so that there are almost no joints between the precast floor slabs 1, 1. In that case, the length in the X direction may be set so that the receiving member 20 (and/or receiving member 20a) can come into contact with the opposing receiving member 20a (and/or receiving member 20) as shown in FIG. 20.

Next, a joint according to a second embodiment will be described. Figure 13 shows a joint 60 according to a second embodiment, where (a) is a perspective view and (b) is a side view. In the following description, the same components as those of the joint 10 in the first embodiment are designated by the same reference numerals, and their description will be omitted. Also, the anchor portion 32 is not necessarily required in each figure, and will be omitted here.

The joint 60 differs from the joint 10 of the first embodiment in that it has a concave-convex engagement portion 62 that directly engages the receiving members 30, 30a in the fitting direction. The concave-convex engagement portion 62 protrudes outward from the lip portion 34a in the X direction, and its end face has multiple concaves and convexes arranged in the vertical direction.

The uneven engagement portion 62 has unevenness that meshes with and engages with each other when the relative positions of the receiving members 30, 30a are in a predetermined position. That is, as shown in FIG. 14, the uneven engagement portion 62 has unevenness 62a formed on one side of the lip portion 34a in the Y direction, and unevenness 62b formed on the lip portion 34a on the other side of the Y direction. The unevennesses 62a, 62b are formed so that the positions of the convex portions and concave portions arranged along the fitting direction are staggered so that the convex portions fit into the concave portions of the other side when they are arranged opposite each other.

The joint 60 is constructed by connecting the receiving members 30, 30a via the connecting member 20, as in the first embodiment described above. That is, as in the first embodiment described above, the connecting member 20 is first disposed between the receiving members 30, 30a, and a torque in the fastening direction is applied to the shaft portion 26.

When the pressing body 28 screwed onto the shaft portion 26 rotates together with the shaft portion 26 and the long side portion 28b of the pressing body 28 is oriented parallel to the X direction, it abuts against the restricting portion 36 of each receiving member 30 and the rotation is restricted. Then, as the shaft portion 26 rotates in the fastening direction, the pressing body 28 gradually moves toward the head portion 26b and abuts against the lower end surface 34b of the receiving members 30, 30a.

As a result, the receiving members 30, 30a and the connecting member 20 are fastened together. Furthermore, if the relative positions of the precast decks 1, 1 are farther apart than a predetermined position, the engaging portion 22 fits into the accommodation portion 34, allowing the precast deck 1 and receiving member 30 to be moved to the predetermined position and positioned. Then, when the precast deck 1 and receiving member 30 move to the predetermined position, the concaves and convexes of the concave-convex engaging portion 62 mesh with each other, and the receiving members 30, 30a engage in the fitting direction.

In this way, by forming the concave-convex engagement portion 62, the joint strength against external forces in the insertion direction of the precast deck slabs 1, 1, i.e., in the direction perpendicular to the XY plane, is improved, and the strength of the joint 60 itself can be improved.

The uneven shape of the uneven engagement portion 62 is not particularly limited, and may be set appropriately, for example, a roughly triangular shape as shown in FIG. 15(a), a roughly wavy shape as shown in FIG. 15(b), an uneven shape in which the meshing sides of the unevenness (contact surfaces between the unevennesses) are parallel to the X direction as shown in FIG. 15(c), or an uneven shape in which the sharp-pointed shape and the contact surfaces between the unevennesses are parallel to the X direction from the base end to the middle as shown in FIG. 15(d). However, if the vertical positions of the receiving members 30 are not aligned, it is preferable to set the opening of the recess to a wide shape and the tip of the protrusion to a narrow shape in order to make it easier for the protrusion to enter the recess.

In addition, in each of the above-mentioned embodiments, the head 26b of the shaft portion 26 is described as contacting the bridge portion 24, but of course, this is not limited to this, and the shaft portion 26 may be arranged in an orientation in which the head 26b can contact the lower end surface 34b of the storage portion 34. That is, the shaft portion 26 may be inserted upside down relative to the bridge portion 24. In this case, the head 26b is formed to have a substantially rectangular shape having a short side portion 28a and a long side portion 28b so as to have a shape corresponding to the pressing body 28. In this way, the head 26b contacts the restricting portion 36, and rotation in the fastening direction is restricted. Furthermore, the pressing body 28 can be screwed onto the shaft portion 26 on the bridge portion 24 side and rotated in the fastening direction to fasten the receiving members 30, 30a and the connecting member 20. In this case, it goes without saying that a female thread body such as a hexagonal nut may be used instead of the pressing body 28.

When the shaft portion 26 is inserted upside down, the head portion 26b does not necessarily have to be in contact with the restricting portion 36 as long as it has a shape that allows it to abut against the lower end surface 34b. In that case, for example, a groove or the like that engages with a tool such as a cross recess or a slot is formed at the tip of the shaft portion 26. Then, the female threaded body screwed onto the shaft portion 26 is fixed in a state of abutment against the bridge portion 24, and the shaft portion 26 is rotated in the fastening direction using a tool or the like to fasten the receiving members 30, 30a and the connecting member 20.

In addition, while the above description is based on an example in which the pressing body 28 is screwed onto the male threaded portion 26a of the shaft portion 26, this is of course not limited to this, and the shaft portion 26 and the pressing body 28 may be integrated. In this case, it is preferable that the pressing body 28 is rotatable together with the shaft portion 26 by a predetermined angle, and that the pressing body 28 is displaceable in the axial direction.

For example, as shown in FIG. 16(a), the shaft portion 26 is slidably inserted into the insertion hole of the bridge portion 24, and a biasing member 70 is provided to bias the end face of the head 26b away from the bridge portion 24 in the axial direction. This allows the pressing body 28 to rotate together with the shaft portion 26 in a position where it does not interfere with the step portion 38, and to abut against the connecting member 20. That is, the shaft portion 26 is pressed and slid in a direction against the biasing member 70, while rotating the shaft portion 26 so that the long side portion 28b is parallel to the X direction. Then, when the pressure on the shaft portion 26 is released and the shaft portion 26 is biased by the biasing member 70, the pressing body 28 abuts against the lower end surface 34b as shown in FIG. 16(b).

In addition, in the above embodiment, the engaging portion 22 is described as being in close contact with the inner circumference of the storage portion 34, but the inner space of the storage portion 34 may be set to be larger than the engaging portion 22, at least as long as the engaging portion 22 can engage within the storage portion 34. In this way, a gap is created between the inner surfaces 40a to 40d of the storage portion 34 and the engaging portion 22, so that the relative positions of the precast deck slabs of the receiving members can be positioned within a specified range.

In addition, in the process of positioning, the distance between the receiving members 30, 30a is determined by the position of the engaging portion 22 entering the storage portion 34, so that a pressure force that can be called a post-stress rather than a pre-stress can be applied to the hardening fluid injected between the precast floor slabs 1, 1. Specifically, the precast floor slabs 1, 1 are separated from each other from a predetermined position and the engaging portion 22 of the connecting member 20 is not inserted to the innermost part of the storage portion 34 in advance, which is the provisional assembly state. The state in which the engaging portion 22 of the connecting member 20 is inserted to the innermost part is the actual assembly state, and the hardening fluid is injected between the precast floor slabs 1, 1 in the provisional assembly state. Then, after hardening to a certain degree or more, if the assembly is shifted to the actual assembly state, the engaging portion 22 of the connecting member 20 presses the inner peripheral surface 40a as shown in FIG. 17, and a compressive pressure force can be applied to the hardening fluid between the precast floor slabs 1, 1.
Of course, it goes without saying that the precast deck slabs 1, 1 may be brought closer to each other than the specified position as a temporary assembly state.

In addition, in the present invention, the distance between the receiving members 30, 30a is determined according to the length of the bridging section in the X direction, so by replacing multiple connecting members with different bridging section lengths, it is possible to apply prestress to the hardening fluid injected into the gap (joint allowance) between the connected precast deck slabs 1, 1.

Specifically, a short connecting member (referred to as short connecting member 82) and a long connecting member for the main assembly (referred to as long connecting member 82) are used. Here, the long connecting member 82 has a long bridging portion 82a that is longer in the X direction than the short bridging portion 80a of the short connecting member 80. Furthermore, the length of the long bridging portion 82a in the X direction is set so that it is longer than the short bridging portion 80a by the amount of elongation in the X direction that the short bridging portion 80a can extend in the elastic deformation range.

The precast decks 1, 1 are connected to each other by multiple joints 10. Here, FIG. 18 is a diagram showing the procedure for applying prestress by rearranging the connecting members, and the precast decks 1, 1 shown in FIG. 18(a) are connected by three joints 10. That is, each precast deck 1 has three support members 30 (or support members 30a) arranged in parallel at approximately equal intervals along the Y direction. The precast decks 1, 1 are positioned by connecting the support members 30, 30a using short connecting members 82.

Next, of the multiple joints 10, the short connecting members 82 are removed from the joints 10 located at both ends in the Y direction, and replaced with long connecting members 80. Therefore, the short connecting member 82 of the joint 10 located at the middle position in the Y direction shown in Figure 18 (b) is stretched in the elastic deformation range due to the tensile force in the X direction, and this is the provisionally assembled state.

In this temporary assembly state, a hardening fluid is injected into the gap between the precast decks 1, 1. Note that in order to prevent the hardening fluid from adhering to the long connecting member 80, an anti-adhesion member such as a covering or plate material may be placed around the long connecting member 80 in advance.

After the hardening fluid hardens to a certain degree of hardness and becomes a hardened body, the long connecting members 80 are removed from the joints 10 at both ends shown in Figure 18 (c) and replaced with short connecting members 82 for final assembly. As a result, inside the hardened body, a force acts on the short connecting members 82, which were stretched in advance when they were replaced, as they try to return to their original length, applying a compressive force to the hardened body and providing prestress. This makes it possible to reinforce the hardened body.

After applying prestress, the short connecting members 82 may be left exposed, or a hardening fluid may be injected to seal the joints between the precast decks 1, 1 so that they are flush with the precast decks 1, 1. The number of joints 10 for connecting the precast decks 1, 1 to each other is not particularly limited, and they may be connected with two joints 10, or with four or more joints. The short connecting members 82 may be used for temporary assembly, and the long connecting members 80 may be used for actual assembly.

The precast deck slabs 1, 1 may also be connected with multiple joints 10 and cotter joints of other structures. As long as the precast deck slabs 1, 1 can be positioned relative to each other at least by the joints 10, the number and arrangement of the joints 10 and cotter joints may be set appropriately. For example, the joints 10 and cotter joints may be arranged alternately, the joints 10 may be positioned at both ends of the precast deck slab 1 in the Y direction and cotter joints may be arranged between the joints 10, or the joints 10 may be positioned in the center and cotter joints may be arranged on both sides of the center.

In addition, in each of the above-described embodiments, the connecting member 20 is pressed so that the engagement portion 22 fits into the accommodation portion 34 by the axial force generated by rotating the shaft portion 26 in the fastening direction, but it is of course possible to omit the shaft portion 26 from the connecting member 20 and directly press the connecting member 20 with a tool such as a hammer.

In addition, in each of the above-mentioned embodiments, the insertion hole formed in the bridge portion 24 is not limited to a through hole, as long as it is a hole into which the shaft portion 26 can be inserted. For example, as shown in FIG. 19(a), a non-through insertion hole 86 may be drilled in the lower end surface of the bridge portion 24. In that case, a male screw pin 88 as a shaft portion is inserted into the insertion hole 86 from the lower side of the bridge portion 24 and fixed. Specifically, a female screw helical thread is provided on the inner peripheral surface of the insertion hole 86, and further, a male screw portion 88a having a male screw helical groove that screws into the female screw helical thread and a head portion 88b provided at the base end of the male screw portion 88a are provided. Then, as shown in FIG. 19(b), the male screw pin 88 is screwed into the insertion hole 86, and the head portion 88b is abutted against the lower end surface 34b to fasten the connecting member 20 and the receiving members 30, 30a to form a joint.

The shape of the receiving members 30, 30a is not particularly limited. For example, as shown in FIG. 21, the outer shape in plan view may be substantially wedge-shaped. That is, the width a1 of one end side in the X direction where the lip portion 34a and the inner peripheral surface 40a in the X direction are provided may be narrower than the width a2 of the other end side in the X direction (the inner peripheral surface 40b side). If such a wedge-shaped receiving member 30, 30a is used, the tensile resistance against tension in the X direction between the precast floor slab and the precast floor slab is improved. Therefore, the receiving member 30, 30a and the precast floor slab are fixed more firmly.

The anchor portion 32 provided on the receiving member 30, 30a may be provided integrally with the receiving member 30, 30a or may be a separate member. The shape of the separate anchor portion 32 is not particularly limited, and the material and shape may be appropriately set, such as a deformed steel bar, a threaded reinforcing bar, a round bar, a U-shaped reinforcing bar, a plate, etc.
Of course, even if the anchor portion 32 is an integral part, its shape is not particularly limited.

When the separate anchor portion 32 is disposed on the receiving member 30, 30a, it is preferable to provide an anchor disposing groove in the receiving member 30, 30a and fit and fix the anchor portion 32. Of course, other fixing means such as welding, adhesion, and bonding may be used between the anchor portion 32 and the receiving member 30, 30a. Also, the anchor portion 32 may be fixed by forming the insertion end of the anchor portion 32 into a male thread shape and forming the inner peripheral surface of the anchor disposing groove of the receiving member 30, 30a into a female thread shape to screw the anchor portion 32 into the receiving member 30, 30a.
Furthermore, in each of the above-described embodiments, the accommodation portion 34 has been described as having a recessed shape, but it goes without saying that the accommodation portion 34 may have a hole shape penetrating the receiving members 30, 30a.

Figure 22 is a perspective view showing the configuration of another joint, in which the joint 200 comprises a receiving member 210, 210a having a substantially conical receiving portion 212 and a connecting member 220 having a substantially conical engaging portion 222. The receiving members 210, 210a have concave-convex engaging portions 214, 214a that protrude outward along the X direction, and the concave-convex engaging portions 214, 214a have concaves and convexes that can engage with each other in the Z direction by meshing with each other. Therefore, when the concave-convex engaging portions 214, 214a of the receiving members 210, 210a mesh with each other and engage with each other, their relative positions become predetermined positions. The receiving portion 212 has an opening at the top, and a female screw helical thread for installing the lid member 230 is arranged on the inner peripheral surface near the opening. In other words, the shape of the inner peripheral surface of the receiving portion 212 is set so that the lid member 230 having a male screw helical groove on the outer peripheral surface can be screwed and fixed.

In addition, in the receiving members 210 and 210a, the notches 216 into which the bridge portions 220 can be fitted are shaped to expand in a V-shape along the X-direction. In other words, they are formed so as to gradually expand from the storage portion 212 side toward the outside in the X-direction.

Figure 23 shows a connecting member 220, (a) being a perspective view and (b) being a side view. The connecting member 220 is formed by a pair of engaging portions 222 connected by a bridging portion 224. Here, the bridging portion 224 has a base portion that connects to the engaging portion 222 and has a widened V-shape so as to correspond to the shape of the notch 216. In other words, the bridging portion 224 has a shape in which the width along the Y direction gradually increases from the base side (the engaging portion 222 side) toward the center.

In addition, at least a pair of connecting part side locking parts 224a that protrude in the Z direction are formed on the lower end surface of the connecting member 220. The connecting part side locking parts 224a are disposed in positions facing the shaft part 26 on the X direction side, and here, are disposed on both sides of the shaft part 26 in the X direction. The connecting part side locking parts 224a function as part of the rotation prevention mechanism of the pressing body 226 described later.

The shaft 26 is inserted through a central through hole of the bridge portion 224, and the pressing body 226 is disposed on the male screw portion 26a formed on the shaft 26. The pressing body 226 has a main body portion having a substantially rectangular shape in plan view with short and long sides, and a pressing body side locking portion 226a which is a cylindrical protrusion having an elliptical or rectangular shape in plan view and disposed on the surface of the main body portion facing the bridge portion 224. Similarly to the pressing body 28 described above, the pressing body 226 also has a female screw hole which screws into the male screw portion 26a and through which the shaft 26 can be inserted. The pressing body side locking portion 226a has a long side portion in plan view parallel to the long side portion of the pressing body 226 and is set longer than the interval between the pair of connecting portion side locking portions 224a, and has a width set so that the short side portion can be positioned between the pair of connecting portion side locking portions 224a.
Therefore, the short side portion of the pressing body side locking portion 226a is positioned between the connecting portion side locking portions 224a, thereby forming a rotation prevention mechanism for the pressing body 226. In other words, when the pressing body 226 rotates from a state in which the pressing body side locking portion 226a is positioned between the connecting portion side locking portions 224a, the pressing body side locking portion 226a comes into contact with the connecting portion side locking portions 224a and is locked in the circumferential direction because the long side portion of the pressing body side locking portion 226a is longer than the interval between the connecting portion side locking portions 224a. As a result, this functions to prevent the pressing body 226 from rotating.

According to the joint 200 having the above-mentioned configuration, when the connecting member 220 is installed on the receiving members 210, 210a with the head 26b pinched, the pressing body 226 can be prevented from rotating from a predetermined state. Specifically, when the pressing body 226 shown in FIG. 24 is oriented so that the short side portion is parallel to the X direction and the connecting member 220 is lifted by pinching the head 26b, the shaft portion 26 is raised relative to the bridge portion 224 and the pressing body side locking portion 226a abuts against the lower end surface of the bridge portion 224 between the pair of connecting side locking portions 224a. At this time, even if an external force that can rotate the pressing body 226 relative to the shaft portion 26 acts on the pressing body 226, the pressing body side locking portion 226a abuts against the connecting body side locking portion 224a to restrict the rotation. Therefore, the pressing body 226 can be prevented from contacting the receiving members 210, 210a while the engaging portion 222 is being fitted into the accommodation portion 212 while the head 26b is pinched.
Of course, here, the connecting member 220 is configured to prevent relative rotation with the pressing body 226 by the connecting side locking portion 224a provided on the connecting member 220 side, but the present invention is not limited to this and may be configured to provide a locking portion on the pressing body 226 side, for example on the upper surface of the pressing body 226, that can be locked with the connecting member 220.

In addition, by using the joint 200, the range of misalignment between the receiving members along the Y direction that can be aligned can be expanded compared to the case where the pyramidal engagement portion 22 described above is fitted into the accommodation portion 34. Specifically, as shown in FIG. 25, even if the connecting member 220 is tilted with respect to the X and Y axes on the XY plane, the engagement portion 222 can be accommodated in the accommodation portion 212. Therefore, it is possible to accommodate a wider range of misalignment along the Y direction.

Furthermore, by forming the shape of the notch 216 and the base of the bridge portion 224 in a V-shape, the engagement strength between the conical receiving portion 212 and the engagement portion 222 in the X direction can be improved.
In addition, since the uneven engagement portions 214, 214a are located on both sides of the notch 216 in the Y direction, the gap between the uneven engagement portions 214, 214a along the Y direction for the pressing body 226 to pass through will be narrowed due to the positional deviation between the receiving members 210, 210a in the Y direction. Therefore, the installation positions and width along the Y direction of the uneven engagement portions 214, 214a are set so that a gap for the pressing body 226 to pass through can be reliably secured even if at least the receiving members 210, 210a are misaligned in the Y direction.

The screw structure between the lid member and the storage section is not limited to the above, and may be configured, for example, by forming a male screw helical groove on the storage section side and a female screw helical rib on the lid member side. That is, a substantially cylindrical tube section that surrounds the opening of the storage section is disposed on the upper surface of the engagement section, and a male screw helical groove is formed on the outer circumferential surface of the tube section, while the lid member has a concave cross section and a female screw helical rib is formed on the inner circumferential surface, and the female screw helical rib of the lid member is screwed into the male screw helical groove of the tube section, thereby blocking the opening at the top of the storage section with the lid member.

In addition, the precast floor slab 1 is moved by the engagement portion 22 and the storage portion 34 abutting their inclined surfaces and the outer peripheral surface of the engagement portion 22 pressing the inner peripheral surface of the storage portion 34. However, if at least one of the outer peripheral surface of the engagement portion 22 and the inner peripheral surface of the storage portion 34 is an inclined surface, the precast floor slab 1 can be moved. For example, as shown in FIG. 29(a), the outer peripheral surface of the engagement portion 22 has a vertical surface 400 (non-inclined surface) parallel to the insertion direction, and the precast floor slab 1 may be moved when the inclined inner peripheral surface 40a (or inner peripheral surface 40b) and the vertical surface 400 abut or press against each other. Also, as shown in FIG. 29(b), the engagement portion 22 has an inclined outer peripheral surface, the storage portion 34 has a vertical surface 410 (non-inclined surface) on the inner peripheral surface on the opening side, and the precast floor slab 1 may be moved when the inclined outer peripheral surface of the engagement portion 22 and the vertical surface 410 of the storage portion 34 abut or press against each other. In addition, since the vertical surfaces 400 and 410 come into contact with the inclined surfaces at their corners, they may be chamfered to provide corners or rounded surfaces so as not to damage the inclined surfaces.

The shaft portion 26 may be configured so that it breaks when a torque and/or axial force of a predetermined value or more is applied, and a part of it can be separated and dropped together with the pressing body screwed to the male screw portion 26a. For example, a weak portion 310 (see FIG. 26) having a V-groove engraved in the circumferential direction is provided on the peripheral surface of the male screw portion 26a of the shaft portion 26. If the shaft portion 26 breaks at the weak portion 310 when a torque of a predetermined value or more is applied to the shaft portion 26, it becomes possible to remove the male screw portion 26a extending below the bridge portion 24. The engraving for providing the weak portion 310 is performed by an appropriate method such as cutting or plastic processing, and the method is not limited. In addition, a hole may be formed in the male screw portion 26a that is separated by breaking, or a sling may be provided, and a string, chain, wire, etc. may be connected to the hole or sling. By connecting a string, chain, wire, etc. to the male screw portion 26a in this way, the male screw portion 26a that has been separated and dropped and the pressing body 28 that is screwed to it can be easily collected by pulling it up. Also, instead of the male threaded portion 26a, a hole or a hanging device may be provided on the pressing body 28 to which a string, chain, wire, etc. can be attached, which also makes it possible to easily retrieve the male threaded portion 26a and pressing body 28 after they have fallen by pulling them up.

The connecting member 20 and the receiving members 30, 30a are fixed by fastening the shaft portion 26 and the pressing body 28, but the engaging portion 22 and the receiving member 30 (30a) may also be fixed using a bolt. For example, the engaging portion 22 may be drilled to provide a through hole 240 (see FIG. 26) parallel to the axial direction, and a female threaded hole (see FIG. 26) may be provided at the bottom of the accommodating portion 34. Then, the bolt 250 (see FIG. 26) may be inserted through the through hole 240 of the engaging portion 22 and screwed into the female threaded hole 260 to fix the engaging portion 22 to the receiving member 30 (30a).

26 shows the configuration of another joint, where (a) is a plan view, (b) is a cross-sectional view taken along line A-A, and (c) is a cross-sectional view taken along line B-B. A through hole 240 is provided in the engaging portion 22, and the through hole 240 is formed by drilling substantially the center of the engaging portion 22. The through hole 240 is provided along the direction in which the engaging portion 22 is fitted into the housing portion 34. The receiving members 30, 30a have a female screw hole 260 in the bottom portion.
Furthermore, a bolt 250 is provided to fix the engagement portion 22 and the receiving members 30, 30a. The bolt 250 can be inserted into the through hole 240 and can be screwed into the female threaded hole 260, and has a shaft portion 252 with a male thread portion 250a formed at one end, and a head portion 254 with a hexagonal outer periphery. The head portion 254 has an outer shape that is longer in length (width) in the axial orthogonal direction perpendicular to the axis than the shaft portion 252.

The bolt 250 is tightened after the engagement portion 22 is fitted into the accommodation portion 34. Specifically, the engagement portion 22 is first fitted into the accommodation portion 34. Then, the bolt 250 is inserted into the through hole 240 of the engagement portion 22, and the male threaded portion 250a is screwed into the female threaded hole 260 to tighten the bolt.

The inner peripheral surface of the storage section 34 may include a vertical surface 300 extending approximately vertically between the opening edge and the bottom as shown in FIG. 26(b) as long as the cross-sectional shape is, for example, approximately bowl-shaped, approximately conical, approximately truncated conical, etc., and includes at least a tapered surface that gradually narrows from the opening edge toward the innermost part. That is, the opening edge may have a slope for inducing the insertion of the engagement section 22, and the inner peripheral surface may have a vertical surface (first surface) 300 that is approximately parallel to the insertion direction of the engagement section 22 from the slope, and a tapered surface (second surface) 302 that gradually narrows from the vertical surface 300 toward the bottom side. In that case, the outer peripheral shape of the engagement section 22 may be a shape that follows the inner peripheral shape of the storage section 34. That is, when the engaging portion 22 is accommodated in the accommodating portion 34, the engaging portion 22 may have an outer peripheral surface including a vertical surface 22a that can be in sliding contact with the vertical surface 300 parallel to the vertical surface 300, and an inclined surface 22b that is inclined parallel to the inclined surface 302 and can abut against the inclined surface 302.

In the above embodiment, the precast decks 1, 1 can be aligned in height even if they are misaligned in the height direction. However, it is also possible to fix the precast decks 1, 1 to each other using the joints 10 when they are misaligned in the height direction by a specified amount. In that case, the engagement part 22 is inserted into the rear part of the receiving part 34, which has the lower set height, of the receiving parts 30, 30a, with a spacer (intervening part) 270 interposed therebetween.

Here, FIG. 27 shows the connection between receiving members 30, 30a of different heights, where (a) is a cross-sectional view showing receiving members 30, 30a at different height positions, and (b) is a cross-sectional view showing receiving members 30, 30a fixed by a joint. The spacer 270 is a washer-like member having a substantially annular shape, and has a hole in the center through which the bolt 250 can be inserted. The spacer 270 also restricts the depth to which the engaging portion 22 can be inserted, and positions the engaging portion 22 in the accommodating portion 34 at a position shallower by a depth h from the innermost portion. That is, the spacer 270 abuts against the engaging portion 22 in the accommodating portion 34, restricting the movement of the engaging portion 22 in the insertion direction.

Specifically, when the height positions of the opposing precast floor slabs (not shown) are made different and the receiving member 30 is set at a position higher than the receiving member 30a by the length h shown in FIG. 27(a), a spacer 270 having a thickness that matches the height difference (length h) between the receiving members 30 and 30a is placed before the connecting member 20 is installed, and then the connecting member 20 is placed. When placing the connecting member 20, a torque in the fastening direction is applied to the shaft portion 26 inserted into the bridging portion 24. As a result, as shown in FIG. 27(b), the pressing body 28 abuts against the lower end surface of the receiving member 30a, and the shaft portion 26 cannot rotate in the fastening direction. Then, as shown in FIG. 27(c), the bolt 250 is inserted into the through hole 240 of the engaging portion 22, and the male screw portion 250a is screwed into the female screw hole 260 to rotate the bolt 250 in the fastening direction.
In this state, by further applying torque in the fastening direction to the shaft portion 26 and inputting an overload to the fragile portion 310, the shaft portion 26 is broken at the fragile portion 310, and the male thread portion 26a is separated and dropped together with the pressing body 28, as shown in Fig. 27(d). Of course, it is desirable to pick up and remove the dropped portion. Also, the part of the shaft portion 26 remaining after the breakage may be removed by pulling it out from the bridge portion 24.

In this way, by disposing the spacer 270, the position of the engaging portion 22 that is inserted into the receiving member 30a is shallower than the innermost portion by the length h, and while the receiving members 30, 30a are set to a predetermined height difference, the connecting member 20 can be disposed so that the bridging portion 24 is in a substantially horizontal position between the receiving members 30, 30a and both engaging portions 22 are held substantially horizontally.

The depth to which the engaging portion 22 can be inserted may be restricted by a method other than providing a spacer 270. For example, the depth to which the engaging portion 22 can be inserted may be restricted by providing an intervening member 280 that can be displaced in the depth direction, as shown in FIG. 28(a). The intervening member 280 is a substantially cylindrical member that is interposed between the female threaded hole 260 and the bolt 250. The intervening member 280 has an outer peripheral male thread 280a formed on its outer circumferential surface that can be screwed into the female threaded hole 260, and an inner peripheral female thread 280b formed on its inner circumferential surface that can be screwed into the male thread 250a.

The intervening member 280 can protrude into the storage section 34 by rotating relative to the receiving member 30a. That is, the intervening member 280 can advance into the storage section 34 along the axial direction because the outer peripheral male screw portion 280a can screw into the female screw hole 260. Therefore, the depth at which the engagement portion 22 can be inserted can be regulated by positioning the intervening member 280 so that the tip of the intervening member 280 along the advancing direction is present in the storage section 34. For example, as shown in FIG. 28(b), when the height positions of the opposing precast floor slabs (not shown) are different and the receiving member 30a is located higher than the receiving member 30 by a length h', before the connecting member 20 is installed, the intervening member 280 is positioned so that it protrudes into the storage section 34 at a length that matches the height difference (length h') between the receiving members 30 and 30a. Then, the connecting member 20 is arranged.

Therefore, the depth to which the engaging portion 22 can be inserted is restricted by abutting against the intervening member 280. Therefore, as in the case of arranging the spacer 270, a desired height difference can be set between the receiving members 30, 30a, and the connecting member 20 can be arranged so that the bridging portion 24 is in a substantially horizontal position between the receiving members 30, 30a and both engaging portions 22 are disposed substantially horizontally.
In addition, since the length of the intervening member 280 protruding into the accommodating portion 34 can be changed by threading it into the female screw hole 260, it is possible to more flexibly accommodate the height difference between the receiving members 30, 30a than by providing the spacer 270. That is, in the case of the spacer 270, it is necessary to prepare a plurality of spacers of various thicknesses to accommodate various height differences, whereas in the case of the intervening member 280, it is easier to accommodate height differences than in the case of the spacer, since it is only necessary to manage the number of rotations. Of course, when the spacer 270 is used, if the unit thickness is set, it is easy to accommodate height differences in stages by changing the number of stacked sheets.

In addition, in each of the above-mentioned embodiments, the shaft portion 26 has been described as having a head portion 26b, but the shaft portion 26 may have a generally rod-like shape with the head portion 26b omitted. However, the outer peripheral shape is set so that it can engage with the bridging portion 24 in the axial direction. Specifically, as shown in FIG. 30(a), the shaft portion 430 may have a male threaded portion 432 at one end, and the bridging portion 24 may have a female threaded hole 440 in the center that screws into the male threaded portion 432.

The shaft portion 430 also has a male threaded portion 434 at the other end, into which a separate female threaded member 450 can be screwed, and the pressing body 28 is supported by the female threaded member 450, so that it can be freely fitted to the shaft portion 430. The female threaded member 450 is a substantially disk-shaped member with an open center, and a female threaded portion that screws into the male threaded portion 434 is formed on the open inner peripheral surface. Therefore, it is also possible to configure the pressing body 28 to be loosely fitted into the shaft portion 430 and the female threaded member 450 to be screwed into the male threaded portion 434, thereby attaching the pressing body 28 to the shaft portion 430.

The male threaded portion 432 and the male threaded portion 434 may be set to have threads in opposite directions. For example, if the male threaded portion 432 and the female threaded hole 440 are right-handed threads, and the male threaded portion 434 and the female threaded member 450 are left-handed threads, the shaft portion 430 can be rotated leftward to move the female threaded member 450 (and the pressing body 28) and the bridging portion 24 in a direction in which they approach each other relatively.
That is, when the shaft portion 430 rotates leftward, the female screw member 450 advances in the tightening direction (toward one end where the bridging portion 24, etc. shown in FIG. 30(b) are located) relative to the shaft portion 430, and the pressing body 28 is pressed by the female screw member 450 and moves in the axial direction. Meanwhile, the bridging portion 24 advances in the loosening direction (toward the other end where the female screw portion 450, etc. shown in FIG. 30(b) are located) relative to the shaft portion 430. Therefore, the pressing body 28 and the bridging portion 24 move to positions where they press against each other, and it is possible to position the precast decks 1, 1 in the same way as in the first embodiment.

When arranging the shaft portion 430 as described above, instead of providing a female threaded hole 440, a separate female threaded member 460 may be provided, and as shown in FIG. 30(c), the female threaded member 460 may be screwed into the male threaded portion 432 to regulate the relative position of the bridge portion 24 with respect to the shaft portion 430.

Although the shaft portion 430 has been described as having male thread portions 432, 434 with different orientations at one end and the other end, this is not limited thereto, and it may have two types of spiral grooves, a right-handed spiral groove and a left-handed spiral groove, overlapping in the same area. For details of a male thread having such two types of spiral grooves, please refer to Patent Publication No. 4663813, which is owned by the inventor of the present application. When using a shaft portion having such two types of pairs of spiral grooves, it is also possible to form spiral grooves over the entire axial area of the shaft portion.

Materials that can be used for precast decks include, for example, concrete and various composite materials.

1 ... Precast deck, 10, 60 ... Joint, 20 ... Connecting member, 22 ... Engagement portion, 24 ... Bridge portion, 26 ... Shaft portion, 26a ... Male thread portion, 26b ... Head portion, 28 ... Pressing body, 28a ... Short side portion, 28b ... Long side portion, 30, 30a ... Receiving member, 32 ... Anchor portion, 34 ... Storage portion, 34a ... Lip portion, 34b ... Lower end surface, 36 ... Regulating portion, 38 ... Step portion, 40a, 40b, 40c, 40d...inner surface, 50...head side unevenness, 52...bridging portion side unevenness, 50a, 52a...inclined surface, 50b, 52b...vertical surface, 62...uneven engagement portion, 62a, 62b...unevenness, 70...urging member, 80...long connecting member, 80a...long bridging portion, 82...short connecting member, 82a...short bridging portion, 86...insertion hole, 88...male threaded pin, 88a...male threaded portion, 88b...head.

Claims (5)

A pair of insertion portions provided on a pair of adjacent decks of the bridge,
A bridge deck joint comprising a pair of engaging portions that can be fitted into the fitted portions and a connecting member having a bridging portion that connects the pair of engaging portions,
the bridge portion has a hole passing through in a fitting direction of the engagement portion,
A shaft portion that is inserted into the hole;
a contact body rotatable together with the shaft portion,
The insertion portion has a restricting portion that restricts rotation of the contact body and a space that includes the restricting portion,
The abutment body rotates together with the shaft portion between the pair of insertion portions to enter the space , and is further rotated within the space by a predetermined angle to engage with the regulating portion in the circumferential direction, thereby regulating the rotation,
A bridge deck joint, characterized in that a positioning mechanism is formed between the insertion portion and the engaging portion so that when the engaging portion is inserted into the insertion portion, the engaging portion is positioned relative to the insertion portion. The bridge deck joint according to claim 1, characterized in that the positioning mechanism has an abutment surface on the outer peripheral surface of the engagement portion and/or the inner peripheral surface of the inserted portion that can generate a pressing force on the inserted portion in a direction perpendicular to the insertion direction. The shaft portion has a male thread portion,
The bridge portion of the shaft portion is sandwiched between a head portion fixed to one side and a contact body screwed to the other side, or a female threaded body is screwed to one side and a contact body is fixed to the other side,
The bridge deck joint according to claim 1, characterized in that, upon rotation of the head or female threaded body, the inserted portion and the bridging portion are sandwiched axially between the head or female threaded body and the abutment body. The bridge deck joint according to claim 1, characterized in that it has a fixing part that fixes the engaging part and the inserted part. The fixing portion is a male threaded body,
The engagement portion has a hole through which the male threaded body is inserted,
5. The bridge deck joint according to claim 4, wherein the inserted portion has a female threaded hole into which the male threaded body can be screwed.