JP5384310B2 - Fall bridge prevention device - Google Patents

Description

  The present invention relates to a falling bridge prevention device for connecting a concrete girder and a substructure.

  Conventionally, as a bridge-fall prevention device for connecting a concrete girder and a lower structure, there has been known a bridge-fall prevention device having a structure in which a bracket having a connection portion at the lower portion is fixed to a lower surface of a concrete girder by a vertical anchor bolt or the like. (For example, refer to Patent Document 1).

JP 2007-270471 A

In the conventional case, it is sufficient when the horizontal force or lifting force acting in the event of an earthquake is small, but when the girder is enlarged or the horizontal force or lifting force is increased, the bracket on the girder side is attached. There is a problem that the load on the portion becomes large, stress concentration occurs and the girder side may be damaged, and resistance to horizontal force or lifting force becomes insufficient.
For example, when an existing bearing device is removed and replaced with a bearing device whose seismic performance is enhanced by the method of holding strength, in order to prevent a concrete girder from being dropped, the connection structure between the concrete girder and the falling bridge preventing device is used. Since a bridge prevention device designed on the premise that a horizontal force or lifting force exceeding the designed level will be applied, the connection between the concrete girder and the bridge prevention device is connected to the horizontal force or lifting force. However, it is necessary to connect more securely.
An object of the present invention is to provide a falling bridge prevention device capable of making a connection with a concrete girder more reliable.

In order to solve the above-mentioned problem advantageously, in the falling bridge prevention device of the first invention, in the falling bridge prevention device for connecting the concrete girder and the lower structure, a lateral hole is provided in the side surface of the concrete girder, The concrete girder is arranged such that each side engagement member in an engagement metal fitting provided with a pair of side engagement members provided with insertion holes on the upper side of the board faces both side surfaces of the concrete girder, respectively. A rod-shaped member is inserted and disposed across the lateral hole of the side engagement member and the insertion hole of the side engagement member, and the concrete girder and the engagement fitting are filled with adhesive, non-shrink mortar, or fiber The other end side of the connecting device in which one end side is connected to the lower structure is connected to the connecting portion provided on the lower side of the substrate by being fixed and integrated by a curable filler such as mortar or fiber-containing concrete. Characterized in that the binding.
According to a second aspect of the present invention, in the falling bridge prevention device according to the first aspect, a pair of grooves are provided on both side surfaces of the concrete girder so as not to connect the internal reinforcing bars of the concrete girder, and provided with protrusions that fit into the grooves. The engaging metal fitting is disposed on the concrete girder so that the projection in the engaging metal fitting provided with the side engaging member is fitted in the groove. It is characterized by being fixed by a curable filler such as an adhesive, non-shrink mortar, fiber-containing mortar or fiber-filled concrete, which is filled in between and embedded in the protrusions and grooves.
According to a third invention, in the falling bridge prevention device according to the first invention, a pair of grooves are provided on both sides of the concrete girder so as not to connect the internal reinforcing bars of the concrete girder, and provided with protrusions arranged in the grooves. The engaging metal fitting is arranged on the concrete girder so that the protrusions in the engaging metal fitting provided with the side engaging member are arranged in the groove, and the concrete girder and the engaging metal metal are between them. It is fixed by a curable filler such as an adhesive, non-shrink mortar, fiber-containing mortar, or fiber-filled concrete that is filled so as to fill the protrusions and grooves.
According to a fourth invention, in the fallen bridge prevention device according to any one of the first invention to the third invention, the protrusion is provided with a recess or a through hole.
According to a fifth aspect, in the falling bridge prevention device according to any one of the first to fourth aspects, the corner portion of the protrusion is chamfered.
In a sixth aspect of the present invention, the groove is a groove formed by holding a concrete girder with a water jet.
According to a seventh aspect, in the falling bridge prevention device according to any one of the first to sixth aspects, a gap is provided between an upper portion of each side portion engaging member and a girder side face in a direction perpendicular to the bridge axis. The upper portion of the substrate is formed with an inlet for a curable filler.
According to an eighth aspect, in the fallen bridge prevention device according to the seventh aspect, each of the side engaging members is provided on an inner intermediate inclined surface that inclines so as to be separated from the girder side face toward the upper portion and an upper end portion of the inner intermediate inclined surface. It is characterized by having an upper inner vertical surface to be connected.

According to the first invention, in the falling bridge prevention device of the first invention, in the falling bridge prevention device for connecting the concrete girder and the lower structure, the side hole of the concrete girder is provided with a lateral hole, and the insertion hole is provided in the upper part. In the fitting provided with a pair of side engaging members on the upper side of the substrate, the side engaging members are arranged so as to face both side surfaces of the concrete girder, and the side holes and sides of the concrete girder are arranged. A rod-shaped member is inserted through the insertion hole of the part engaging member, and the concrete girder and the engagement metal fitting are filled with adhesive, non-shrink mortar, fiber-containing mortar or fiber-containing Since the other end side of the connecting device, one end side of which is connected to the lower structure, is connected to the connecting portion provided on the lower side of the substrate by being fixed and integrated by a curable filler such as concrete. The connection between cleat girders and engagement brackets can be ensured, and even if the horizontal force or lifting force is increased by design, the concrete girders can be firmly fixed to the falling bridge prevention device, etc. The effect that an effect can be acquired is acquired.
According to the second or third invention, in the falling bridge prevention device according to the first invention, grooves are provided on both sides of the concrete girder so as not to connect the internal reinforcing bars of the concrete girder, and are fitted or arranged in the grooves. The engaging metal fitting is disposed on the concrete girder so that the protrusion in the engaging metal fitting provided with a pair of side engaging members provided with the protrusions is fitted or arranged in the groove. Since the engagement metal fitting is fixed by an adhesive or a non-shrink mortar filled with the projection and the groove filled between them and a curable filler such as fiber mortar or fiber concrete, With the protrusions provided on the side engaging members, the grooves provided in the concrete girders, and the curable filler provided so as to embed these, the engaging metal fittings are securely confirmed. The girder can be fixed and integrated into the girder so that the girder can be prevented from falling even when a large horizontal force or lifting force is applied. It is done.
According to the fourth invention, in the falling bridge prevention device according to any one of the first to third inventions, since the projection is provided with the recess or the through hole, the effect of ensuring the adhesion of the projection can be achieved. Is obtained.
According to the fifth invention, in the falling bridge prevention device according to any one of the first to fourth inventions, since the corner portion of the projection is chamfered, the corner portion of the projection is chamfered and a curable filler is provided. The stress transmission between the two can reduce the stress compared to the case of the sharp corners in the protrusions, and can eliminate the risk of damage to the curable filler or concrete girder due to stress concentration. Etc. are obtained.
According to the sixth aspect of the present invention, since the groove is a groove formed by holding a concrete girder with a water jet, there is no possibility of causing cracks (fine cracks) in the concrete girder. The tool can be securely fixed, and a predetermined fixing strength can be obtained. On the other hand, when a groove is formed so as to be struck by a rock drill, etc., on a concrete girder, there is a risk of cracks (fine cracks) in the concrete girder. There is a risk of falling, which is not desirable.
In the seventh invention, a gap is provided between the upper part of each side engaging member and the beam side face in the direction perpendicular to the bridge axis, and the inlet of the curable filler is formed by the upper part of the gap. The curable filler can be placed or filled by being introduced from the inlet at the upper part of the gap between the side surface (web side surface) of the bridge perpendicular to the bridge axis and the side engaging member. Thus, it is possible to perform the installation easily, and it is possible to reliably perform the installation, and it is possible to surely integrate the side engaging members and the girders.
According to an eighth aspect of the present invention, each of the side engaging members includes an inner intermediate inclined surface that is inclined so as to be separated from the side surface of the spar toward the upper portion, and an upper inner vertical surface that is connected to an upper end portion of the inner intermediate inclined surface. Therefore, a gap in which a curable filler can be placed can be easily formed between the side surface of the spar and the upper portion of each side engaging member, and between each side engaging member and the side surface of the spar. In addition, it is possible to provide a falling bridge prevention device that can be reliably filled with a curable filler.

It is a front view which shows an example of the engagement metal fitting used in the falling bridge prevention apparatus of 1st Embodiment of this invention. It is a side view of the engagement metal fitting shown in FIG. It is a top view of the engagement metal fitting shown in FIG. It is a bottom view of the engagement metal fitting shown in FIG. It is the sectional view on the AA line of FIG. It is the BB sectional view taken on the line of FIG. It is a perspective view from the front side of the engagement metal fitting shown in FIG. It is a perspective view from the bottom face side of the engagement metal fitting shown in FIG. It is a side view which shows the state which installed the fallen bridge prevention apparatus of 1st Embodiment of this invention in the concrete girder and the concrete lower structure. FIG. 10 is a partially cut longitudinal front view showing the vicinity of the engagement fitting attached to the concrete girder side shown in FIG. 9. FIG. 11 is a partially cut longitudinal front view showing a part of FIG. 10 in an enlarged manner. FIG. 12 is a partially cutaway longitudinal front view showing one side of FIG. 11 in an enlarged manner. It is a cross-sectional plan view of FIG. It is a partially cut longitudinal front view showing a fixing structure of a rod-shaped member in the case where the horizontal hole provided on the concrete girder side is a horizontal hole formed of a recess that does not penetrate in the width direction of the beam. The relationship between the groove | channel provided in a concrete girder and the protrusion of a side part engagement member is shown, Comprising: (a) is a cross-sectional top view which shows the case where a groove | channel about a cover thickness is provided, (b) is about a main reinforcement. FIG. 5C is a cross-sectional plan view showing the case of a deep groove up to a depth of (2), FIG. 3C is a cross-sectional view showing a state in which protrusions are arranged so as to engage with the main reinforcement, and the engaging metal fitting is fixed to the concrete girder by the curable filler. It is a top view. It is a front view which shows the other example of the engagement metal fitting used in the falling bridge prevention apparatus of 2nd Embodiment of this invention. It is a side view of the engagement metal fitting shown in FIG. It is a top view of the engagement metal fitting shown in FIG. It is a bottom view of the engagement metal fitting shown in FIG. It is CC sectional view taken on the line of FIG. It is a perspective view from the front side of the engagement metal fitting shown in FIG. It is a perspective view from the bottom face side of the engagement metal fitting shown in FIG. It is a side view which shows the state which installed the fallen bridge prevention apparatus of 2nd Embodiment of this invention in the concrete girder and the concrete lower structure. FIG. 24 is a longitudinal front view showing the vicinity of the engagement fitting attached to the concrete girder side shown in FIG. 23. FIG. 25 is a partially cutaway longitudinal front view showing a part of FIG. 24 in an enlarged manner. It is a cross-sectional plan view of FIG.

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

  First, referring to FIG. 1 to FIG. 8, a description will be given of an embodiment of the engagement metal fitting 1 that is used in the falling bridge prevention device of the present invention and is fixed to a concrete girder. The engagement metal fitting 1 is a steel substrate. 2, a side engaging member 3 that is disposed on the upper surface side of the substrate 2 and faces the bridge axis in a direction perpendicular to the bridge axis, and a connecting portion including a bracket 4 a provided on the lower side of the substrate 2. 4 is provided.

  Each side engaging member 3 is placed on the upper surface side of the steel substrate 2 so as to face each other at an interval and extend in the bridge axis direction, and for attaching a lower portion of each side engaging member 3. The flange 5 is detachably attached by a plurality of bolts 6. On the lower surface side of the substrate 2, a steel bracket 4 a having a horizontal shaft insertion hole 4 b and its reinforcing rib 4 c are fixed by welding or the like to constitute a connecting portion 4.

  On both sides of the rectangular substrate 2 in the direction perpendicular to the bridge axis (width direction), a plurality of female screw holes (in the illustrated case, according to the number of mounting bolts 6) are provided at intervals in the bridge axis direction. Each side portion is inserted into a bolt insertion hole of a mounting flange 5 provided at a lower portion of the side engaging member 3 and a plurality of mounting bolts 6 screwed into a female screw hole of the substrate 2. The engaging member 3 is detachably attached to the steel substrate 2.

  When the board 2 and the side engaging member 3 are set on the concrete girder 11, the board 2 and the side engaging member 3 may be attached on the site by the mounting bolt 6 or may be integrally attached in advance at the factory. Moreover, the cross-sectional form of the side engaging member 3 as viewed in the bridge axis direction is appropriately set by design according to the cross-sectional form of the concrete girder 11 as viewed in the bridge axis direction.

  Each of the side engaging members 3 includes a vertical upper vertical plate 3a, an intermediate inclined plate 3b that is refracted integrally with the vertical vertical plate 3a, and inclines toward the outer side in the direction perpendicular to the bridge axis, and refracts integrally with the intermediate inclined plate 3b. A vertically connected lower vertical plate 3c and a mounting flange 5 fixed to the lower vertical plate 3c by welding are provided.

  The upper vertical plate 3a, the intermediate inclined plate 3b, the lower vertical plate 3c, and the flange 5 for mounting constitute a side engaging member main body 3d. The side engaging member main body 3d is perpendicular to the bridge axis. Reinforcing vertical ribs 3e are provided on the outer side to reinforce.

  On the inside of the lower vertical plate 3c, a projection 7 made of a vertical steel plate or the like protruding in a direction perpendicular to the bridge axis is fixed by welding or bolts at intervals in the bridge axis direction.

  The side engaging member main body 3d is fixed to the steel substrate 2 of the engaging metal fitting 1 by the attaching bolt 6 when the engaging metal fitting 1 is attached to the grooved concrete girder 11. Configure. As a means for fixing the side engaging member 3 to the substrate 2, in place of the above-described mounting bolt 6, pre-welding at the factory or positioning of the side engaging member 3 at the site is performed, and field welding is performed. You may make it fix by.

  In the illustrated form, the protrusion 7 provided on the inner side of the lower vertical plate 3c in the direction perpendicular to the bridge axis includes an upper protrusion 7a protruding toward the inner side in the direction perpendicular to the bridge axis, and a bridge axis higher than the upper protrusion 7a. A lower protrusion 7b that protrudes inward in the direction perpendicular to the bridge axis with a small amount of protrusion in the right angle direction.

When the engagement fitting 1 as described above is attached to a concrete girder 11 such as an existing concrete girder 11, for example, a lower side surface of the existing concrete girder 11 (projected on the upper surface of the substrate 2 as described later). In order to prevent cutting of reinforcing bars such as main bars or stirrup bars embedded and fixed in the existing concrete girder 11, the reinforcing bars are appropriately searched for, Cover the concrete between the reinforcing bars by exceeding the thickness range of the covering concrete or the thickness of the covering concrete (stirrup or main reinforcing bar), that is, the side of the lower part of the girder indicated by the dotted line S in FIGS. Accordingly, the groove 8 of the concrete girder 11 is provided.
In the present invention, as described above, the grooves 8 are provided so as not to cut the reinforcing bars in the existing concrete girder 11, so that the processing of the existing concrete girder 11 side can be performed by the concrete suspending operation and the horizontal holes 9. Because there is, it is made easy to perform on-site processing. As a suspension device, the groove 8 may be provided by an electric cutter or the like, or a girder is provided by a known suspension device such as a suspension device for jetting a water jet (high pressure water). May be. If the groove 8 is a groove formed by holding a concrete girder with a water jet of a predetermined pressure, there is no possibility of causing cracks (fine cracks) in the concrete girder and there is no possibility of damaging the internal rebar. . If a groove is formed so as to oscillate a concrete girder with a rock drill or the like, cracks (fine cracks) may occur in the concrete girder, so a high level of skill is required when using a cutting machine. .

  Next, the form of the groove | channel provided in the side surface (or lower surface of illustration omitted) of the existing concrete girder 11 is demonstrated. The groove 8 provided in the existing concrete girder 11 may be a groove spaced in the bridge axis direction, or a predetermined length (for example, about the length dimension of the engagement fitting 1 in the bridge axis direction). It is good also as the groove | channel 8 which consists of a continuous recessed part.

In the form shown in FIGS. 10-12, the groove | channel which consists of the vertical groove | channel of the vertical direction opened to the lower surface of a girder in the lower part of the side surface of the intermediate part of the bridge axis direction in the concrete-made girder 11 of T-section 8 is a form in which a plurality are provided in parallel at intervals.
In addition to such a form, it is appropriately set according to the form of the protrusion 7 as described later.

  Next, with reference to FIGS. 9 to 13, the falling bridge prevention device 10 according to the first embodiment of the present invention will be described.

  A horizontal hole 9 (in the case of illustration) penetrating in the vertical direction intermediate portion (web 11a) of a concrete girder 11 such as an existing concrete girder in the direction perpendicular to the bridge axis (in the case shown in FIG. 14) ) Are provided at intervals in the bridge axis direction (two in the illustrated case).

  When longitudinal grooves 8 are provided on both side surfaces of the existing concrete girder 11 in the bridge axis direction in the direction perpendicular to the bridge axis to form a grooved concrete girder 11, the bridge shaft is positioned at a position corresponding to the longitudinal groove 8. A side engagement member body 3d having an L-shaped cross section in which protrusions 7 made of vertical steel plates or the like projecting in a perpendicular direction are fixed by welding or bolts (not shown) at intervals in the bridge axis direction, and the engagement metal fitting 1 is grooved. At the time of installation to the attached concrete girder 11, the engagement metal fitting 1 is configured by being fixed to the steel substrate 2 in the engagement metal fitting 1 by means of bolts 6 for attachment (or welding not shown).

  Further, the side engaging member 3 is set so that the center axis line of each of the upper insertion holes 12 in the side engaging member 3 and the lateral hole 9 provided in the concrete girder 11 substantially coincide with each other.

A rod-like member 13 made of a connecting bolt is inserted through the insertion hole 12 of each side engaging member 3 and the lateral hole 9 of the concrete girder 11, and the nut 14 is placed at the end of the rod-like member 13. Screw in the part.
The gap between the bar-shaped member 13 and the lateral hole 9 of the concrete girder 11 and the gap between the side engaging member 3 are filled with a curable filler 15 to be described later, so that the concrete girder 11 and the bar-shaped member are filled. 13 and the side engaging member 3 are integrated. By connecting the rod-shaped member 13 concrete girder 11 and the side engaging member 3, the engaging bracket 1 is connected to the lower structure 16 mainly when an uplift force in the vertical direction during an earthquake is applied. In the state of being connected by the device 18, it becomes possible to resist.

In the state in which the engagement metal fitting 1 is disposed so that the substrate 2 abuts (or is spaced from) the lower surface of the grooved concrete girder 11, the projection 7 on the side engagement member main body 3d is The position of the side engagement member main body 3d in the direction perpendicular to the bridge axis is finely adjusted to the position where the groove 8 is sufficiently inserted and engaged, and is fixed to the substrate 25 by bolts (in the case of illustration) 6 or welding.
When the position adjustment is large, the bolt hole provided in the mounting flange 5 is preferably a horizontally long or large circular hole.

  Between the protrusion 7 of the side engaging member 3 and the groove 8 of the grooved concrete girder 11, if necessary, a ground treatment is applied to fill the adhesive, or the side portion including the protrusion 7 The side surface of the girder main body 3d and the entire surface of the grooved concrete girder 11 where the side engaging member main body 3d abuts are appropriately grounded so that they can be engaged with each other by applying an adhesive. May be. Alternatively, instead of these, a curable filler such as non-shrink mortar, fiber-containing mortar, or fiber-containing concrete may be filled and integrally engaged.

  As described above, in a state where the engagement fitting 1 is attached to the concrete girder 11, as shown in FIG. 9, the attachment portion 17 formed of a bracket fixed to the lower structure 16, and the engagement fitting 1 The connecting portion 4 is a connecting rod 19 (in the case of illustration) provided with a length adjusting bracket such as a turnbuckle 19a, a connecting chain, a connecting PC steel material, a carbon fiber wire (or a carbon fiber strand), or a composite. It is connected by a connecting device 18 such as a resin fiber wire (or a synthetic resin fiber strand) (both not shown), and the concrete girder moves mainly in the direction of the bridge axis at the time of an earthquake and falls down. Is prevented. In the above-described embodiment, one end and the other end of the connecting device 18 are connected to the mounting portion 17 on the lower structure 16 side by the horizontal shaft 22 and a nut attached thereto, etc. The other end portion of the connecting device 18 is connected to the connecting portion 4 formed of the bracket 4a by the horizontal shaft 23 and a nut attached to the horizontal shaft 23.

  A fixing portion to the concrete girder 11 by adhesion of the inner surface of the side engaging member 3, the protrusion 7 and the curable filler 15, a rod-shaped member 13, the concrete girder 11, the engagement fitting 1, and the curability. One of the connecting portions by filling with the filler 15 does not act on either the horizontal force in the bridge axis direction or the lifting force in the event of an earthquake, but both act together. However, in the present invention, a reliable connection and integration when a horizontal force in the direction of the bridge axis in the event of an earthquake is applied mainly to the lifting force due to the connection by the rod-like member 13 by the fixing portion on the protrusion 7 side is expected. ing.

  The falling bridge prevention device 10 is configured by the engagement metal fitting 1 attached to the concrete girder 11 and the connecting device 18 that connects the other end of the connecting device 18 that is connected at one end to the lower structure 16. .

  As described above, in the present invention, in the falling bridge prevention device for connecting the concrete girder 11 and the lower structure 16, the pair of lateral holes 9 are provided in the side surface of the concrete girder 11 and the insertion hole 12 is provided in the upper part. The side engaging members 3 in the fitting 1 having the side engaging members 3 on the upper side of the substrate 2 are arranged so as to face both side surfaces of the concrete girder 11, respectively. The bar-like member 13 is inserted through the horizontal hole 9 and the insertion hole 12 of the side engagement member 3, and the concrete girder and the engagement metal fitting are filled with an adhesive or no adhesive. A connecting device fixed and integrated with a curable filler such as shrink mortar, fiber-containing mortar, or fiber-containing concrete, and one end side connected to a lower structure on a connecting portion provided on the lower side of the substrate Since the other end is connected, even with a concrete girder, the connection between the concrete girder and the fitting can be ensured, and the stress burden on the concrete girder side is reduced, so stress concentration Thus, it is possible to obtain an effect such as no risk of damage.

  Further, according to the present invention, the grooves 8 are provided on both side surfaces of the concrete girder 11 so as not to connect the internal reinforcing bars of the concrete girder, and the protrusions 7 of the fitting 1 are fitted into the grooves 8. The engaging metal fitting 1 is disposed on the concrete girder 11 so as to cause the concrete girder 11 and the engaging metal fitting 1 to be filled between them so that the protrusion 7 and the groove 8 are filled. Or, since they are fixed by a curable filler 15 such as non-shrink mortar, fiber-containing mortar, or fiber-containing concrete, the projection 7 provided on the side engaging member 3 and the groove 8 provided on the concrete girder 11 are connected to these. With the curable filler 15 provided so as to be embedded, the engagement fitting 1 can be reliably fixed and integrated with the concrete girder 11, and therefore, in the conventional case Remote, also act a large horizontal force or upper lift, it is possible to prevent the digits to girder.

If the protrusion 7 is provided with a recess or a through hole 7c, the curable material 15 and the protrusion 7 can be reliably attached.
Further, in the embodiment, since the chamfering 7d is applied to the corner portion on the inner side of the web side of the protrusion 7, the corner portion becomes a flat surface. Therefore, the corner portion of the protrusion 7 is chamfered and cured. In the stress transmission with the curable filler, the stress can be reduced as compared with the case of the acute corner portion of the protrusion, and the curable filler 15 or the concrete girder 11 may be damaged by the stress concentration. Can be eliminated

  When practicing the present invention, the concrete girder 11 may be an existing or new concrete girder.

  When practicing the present invention, as the protrusions 7 provided on the side engaging member 3, only plate-like protrusions such as steel plates are vertically or inclined (inclined or bridged in one direction) at intervals in the bridge axis direction or the vertical direction. A plurality of bar-shaped protrusions such as reinforcing bars or deformed steel bars may be provided in the bridge axis direction or the vertical direction, and these may be combined alternately. A plurality may be provided at intervals. In such a case, depending on the arrangement of the projections, a plurality of concrete girder-side grooves are provided vertically or inclined at intervals in the bridge axis direction or the vertical direction, or a long groove or inclined (one direction) Or a groove having a columnar recess, or a plurality of them may be provided at intervals so as to be alternately combined.

  In the case of the above embodiment, the projection 7 is provided on the inner lower portion of the side engaging member 3. However, when the present invention is implemented, a plurality of projections are provided on the upper surface of the steel substrate 2, and concrete is provided. The bottom face of the girder is hung as necessary and provided with a groove, and the protrusion is arranged in the groove, and the bottom face side of the concrete girder and the top face side of the substrate 2 of the engagement metal fitting 1 are formed by the curable filler. These may be fixed and integrated.

  When a groove is provided on the concrete girder 11 side, a groove 8 corresponding to the concrete cover thickness is provided as shown in FIG. 15 (a), or the internal main reinforcement 20 or stirrup as shown in FIG. 15 (b). A groove 8 is provided at a depth at which these reinforcing bars are positioned so as not to cut the bars 21, and the top side of the upper protrusion 7 a in the protrusion 7 is a concrete girder in a projection view in the bridge axis direction. If the lower end of the upper projection 7a of the projection 7 is engaged with the main bar on the spar side, the distal end of the projection 7 is made of concrete. Compared with the integration with the concrete girder 11 in the case of the engagement metal fitting 1 provided so as to be within the cover concrete thickness of the girder 11, the integration with the concrete girder 11 becomes stronger.

  Next, with reference to FIGS. 16-26, the fallen bridge prevention apparatus 10 of 2nd Embodiment of this invention is demonstrated.

  First, with reference to FIG. 16 to FIG. 22, another example of the engagement metal fitting 1 used in the falling bridge prevention device of the present invention and fixed to a concrete girder will be described. The tool 1 and the main part are the same and different in that the shape of the side engaging member 3 attached to the steel substrate 2 is different, but the other parts are the same. The same parts are denoted by the same reference numerals, and the above description is used for simple explanation.

In the example of the engagement metal fitting 1 shown in FIG. 16, each side engagement member 3 has an intermediate inclined surface provided with an inner inclined surface that is inclined so as to be separated from the girder side surface toward the upper portion of the lower vertical plate 3c. A plate 3b and an upper vertical plate 3a having an upper inner vertical surface connected to the upper end of the inner inclined surface are provided. As shown in FIG. 24 or FIG. 25, by fixing the side engaging member 3 to the substrate 2, between the side surface of the spar such as a vertical vertical side surface and the upper portion of each side engaging member 3. The large gap 24 can be formed, and from above between the side surface of the bridge perpendicular to the bridge axis and each side portion engaging member 3, the side surface of the beam (the side surface of the web 11a perpendicular to the bridge axis) and each side member This is a form that can be placed so as to be filled with the curable filler 15 between the joint member 3.
In the embodiment, a gap 24 having an open top is provided between the upper portion of each side engagement member 3 and the side surface of the beam perpendicular to the bridge axis, and the curable filler 15 is formed by the upper portion of the gap 24. Therefore, the curable filler 15 is placed or filled so as to be introduced from above the gap 24 between the side surface (web side surface) of the bridge axis and the side engaging member 3 in the direction perpendicular to the bridge axis. Therefore, the placement work of the curable filler 15 can be facilitated, and the placement can be performed while checking the filling state. 3 and the girder 11 can be fixedly integrated.

  The falling bridge prevention device 10 of the second embodiment of the present invention using the side engaging members 3 as described above is shown in FIGS. 23 to 26 so as to correspond to FIGS. 9 to 11 and FIG. 13, respectively. Yes. Accordingly, the difference from the first embodiment is that the structure of the middle part and the upper part of the side engaging member 3 is different, but the other configuration is the same as that of the first embodiment. The different parts are mainly described, and the same parts are denoted by the same reference numerals.

In the second embodiment, each of the side engaging members 3 is connected to an intermediate inclined plate 3b having an inner inclined surface inclined so as to be separated from the girder side face toward the upper portion and an upper end portion of the inner inclined surface. Since the upper vertical plate 3a having the upper inner vertical surface is provided, as shown in FIG. 24 or FIG. 25, a curable filling is provided between the side surface of the web consisting of the web side surface and the upper portion of each side engaging member 3. A gap 24 in which the material 15 can be placed can be easily formed, and a curable filling is provided between each side engaging member 3 and the side surface of the beam (in the illustrated form, the side surface of the web 11a perpendicular to the bridge axis). It can be set as the fallen bridge prevention apparatus 10 with which the material 15 was filled reliably. Note that an end mold (not shown) is provided on the end side in the bridge axis direction to close the girder side face and the end of each side engaging member 3.
In such a form, the setting of the curable filler 15 is easy and reliable, and the workability can be improved.
In addition, the long rod-shaped member 13 is used for the rod-shaped member 13 because the upper part of each side engaging member 3 spreads so as to expand. Moreover, the rod-shaped member 13 with a suitably large outer diameter is used. As described above, when the upper portion of the side engaging member 3 is separated from the girder side surface in the direction perpendicular to the bridge axis, the width portion of the gap 24 in the direction perpendicular to the bridge axis and the thickness in the direction perpendicular to the bridge axis on the girder 11 side increase. Therefore, the girder 11 can be reinforced and the joint portion between the girder 11 and the falling bridge prevention device 10 can be reinforced. It should be noted that reinforcement or a metal mesh may be appropriately embedded in the gap 24 between the beam 11 and the side engaging member 3 for reinforcement.

  In each of the above embodiments, the through hole 7c is provided in the protrusion 7 so as to enhance the adhesion with the curable filler. However, when the present invention is carried out, a recess or a groove is provided instead of the through hole 7c. You may make it aim at adhesion reliably.

  When the corner portion of the projection 7 is chamfered 7d as in the form shown in the drawing, the acute angle at the projection is obtained in the stress transmission between the chamfer of the corner portion of the projection 7 and the curable filler. Compared to the case of a corner portion, the stress can be reduced, and the effects such as the possibility that the curable filler or the concrete girder can be damaged due to the stress concentration can be obtained. In the illustrated form, the chamfer 7d is provided on the upper side of the upper projection 7a in the projection 7, but the chamfer may be provided on the lower corner portion of the upper projection 7a or may be provided on both.

  When implementing this invention, as the rod-shaped member 13, it is good also as a solid steel rod, a hollow steel pipe, and other rod-shaped steel materials. As a means for preventing the rod-shaped member 13 from coming off in the direction perpendicular to the bridge axis, in addition to the nut 14, a ring-shaped stopper may be attached to the end of the rod-shaped member 13.

The groove 8 provided in the concrete girder 11 (side surface) is a groove 8 formed of a concave portion continuous in the bridge axis direction, and when all the protrusions 7 in the engagement metal fitting 1 are disposed in the groove 8, fibers are included. When mortar or fiber-containing concrete is filled, the strength can be increased as compared with the case where fibers are not mixed.
As said fiber, steel fiber, carbon fiber, glass fiber, synthetic resin fiber, etc. may be used, and it sets suitably by design conditions, such as a short fiber or a long fiber.

Note that the mounting position of the concrete engagement fitting 1 on the concrete girder 11 in the direction of the bridge axis is at most ½ of the span length from the vicinity of the mounting portion 17 of the lower structure 16. Therefore, the length of the connecting device 18 is also about 50 cm to about 1/2 of the span length at the maximum.
The connecting portion 4 may be a form provided with a vertical axis insertion hole in addition to a form provided with a horizontal axis insertion hole 4b, or any other known appropriate form. An appropriate coupling device such as a type coupling device may be substituted.

DESCRIPTION OF SYMBOLS 1 Engagement metal fitting 2 Board | substrate 3 Side part engagement member 3a Upper vertical board 3b Middle inclination board 3c Lower vertical board 3d Side part engagement member main body 3e Reinforcement vertical rib 4 Connection part 4a Bracket 4b Horizontal axis insertion hole 4c Reinforcement rib 5 Mounting flange 6 Bolt 7 Protrusion 7a Upper protrusion 7b Lower protrusion 7c Through hole 7d Chamfer 8 Groove 9 Horizontal hole 10 Fall bridge prevention device 11 Concrete girder 11a Web 12 Insertion hole 13 Bar-shaped member 14 Nut 15 Curable filler 16 Substructure 17 attachment portion 18 connecting device 19 connecting rod 20 main bar 21 stirrup bar 22 horizontal axis 23 horizontal axis 24 gap

Claims (8)

  In a falling bridge prevention device for connecting a concrete girder and a lower structure, a side hole is provided on the side surface of the concrete girder, and a pair of side engaging members having an insertion hole on the upper side is provided on the upper side of the board. The side engaging members of the metal fitting are arranged so as to face both side surfaces of the concrete girder, and a bar-shaped member is inserted across the side hole of the concrete girder and the insertion hole of the side engaging member. And the concrete girder and the engagement fitting are fixed and integrated with an adhesive filled between them or a non-shrink mortar or a curable filler such as fiber mortar or fiber concrete, A falling bridge prevention device characterized in that one end side of the connecting device connected to the lower structure is connected to the connecting portion provided on the lower side of the substrate.   In the engagement fitting provided with a pair of side engagement members each provided with a groove that does not connect the internal rebar of the concrete girder on both side surfaces of the concrete girder, and provided with a projection that fits into the groove The engaging metal fitting is arranged on the concrete girder so that the protrusion fits into the groove, and the concrete girder and the engaging metal metal are filled between them and filled so as to embed the protrusion and the groove. The fallen bridge prevention device according to claim 1, which is fixed by a curable filler such as an adhesive, non-shrink mortar, fiber mortar or fiber concrete.   The above-mentioned engagement metal fitting provided with a pair of side engagement members each provided with a groove that does not connect the internal rebar of the concrete girder on both side surfaces of the concrete girder, and provided with a protrusion disposed in the groove The engaging metal fitting is arranged on the concrete girder so that the protrusion is arranged in the groove, and the concrete girder and the engaging metal are filled between them and are filled so as to embed the protrusion and the groove. 2. The falling bridge prevention device according to claim 1, which is fixed by a curable filler such as an agent, non-shrink mortar, fiber-containing mortar, or fiber-containing concrete.   The falling bridge prevention device according to any one of claims 1 to 3, wherein the protrusion is provided with a recess or a through hole.   5. The falling bridge prevention device according to claim 1, wherein a corner portion of the protrusion is chamfered.   6. The falling bridge prevention device according to claim 2, wherein the groove is a groove formed by holding a concrete girder by a water jet.   A gap is provided between an upper portion of each side portion engaging member and a girder side face in a direction perpendicular to the bridge axis, and an inlet for a curable filler is formed by the upper portion of the gap. Item 7. The falling bridge prevention device according to any one of items 1 to 6.   Each of the side engaging members includes an inner intermediate inclined surface that is inclined so as to be separated from the side surface of the spar toward the upper portion, and an upper inner vertical surface that is connected to an upper end portion of the inner intermediate inclined surface. The fallen bridge prevention device according to claim 7.

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