JP6532792B2 - Precast floor slabs and bridges - Google Patents

Description

  The present invention relates to a precast floor slab provided above a main girder and a bridge to which it is attached.

  Conventionally, for the purpose of constructing a bridge, for example, the disclosure techniques of Patent Documents 1 to 3 have been proposed.

  In the bridge disclosed in Patent Document 1, on the lower surface of a precast floor slab or the like, a groove portion fitted with a stud dowel on a main girder made of H-shaped steel is formed along the bridge axial direction. In the bridge disclosed in Patent Document 1, a pair of communication holes extending from the front and rear ends of the groove to the upper surface of the floor slab is penetrated in the floor plate, and non-shrinkable mortar is filled in the groove from the one communication hole. Air from the other communication hole. In the bridge disclosed in Patent Document 1, both side surfaces along the bridge axis direction of the groove portion are curved in a meander shape (tapered shape) in plan view, and the mortar is filled in the groove portion across the both side surfaces. And the floor plate are integrated.

  The reinforcement structure of the existing floor slab disclosed in Patent Document 2 is a floor slab main body whose upper surface is formed as an uneven surface by cutting the existing floor slab, and a precast that faces the upper surface of the floor slab main body with a gap. It is comprised by the plate-shaped member made from, and the filler filled between the floor slab main body and the plate-shaped member. The uneven surface is formed on the lower surface of the plate-like member, and a plurality of through holes penetrating in the vertical direction are formed. A plurality of through holes are formed in the plate member at predetermined intervals. Further, the through hole is formed so that the inner diameter of the through hole gradually increases in the vicinity of the middle of the plate-like member in the height direction. The through hole is formed in a shape that allows insertion of the anti-slip member disposed on the upper surface of the floor slab main body.

  The joint structure of the girder and floor slab disclosed in Patent Document 3 has a configuration in which a time-hardenable material is provided between the precast girder and the precast floor slab. The precast floor slab is installed at the top of the precast girder, with the precast girder mounted on an abutment or a bridge pier or the like. The lower end face of this precast floor slab is washed out so as to be rough. Moreover, the insertion hole is drilled by the precast floor slab. In this insertion hole, the anti-slip member protruding upward from the upper surface of the upper flange of the main girder is inserted from the lower side. In addition, a time-hardening material such as mortar is filled in the insertion hole into which the anti-slip member is inserted.

Japanese Patent Application Laid-Open No. 11-264115 JP 2007-092456 A JP, 2014-015753, A

  However, in the bridge disclosed in Patent Document 1, the height of the groove portion in which the pair of communication holes are provided at both ends is formed substantially horizontal in the bridge axis direction. Therefore, in the bridge disclosed in Patent Document 1, when air bubbles are generated between the communication holes and the communication holes when mortar is filled in the grooves, the air bubbles accumulated above the grooves are discharged toward the communication holes. It is hard to be done and there is a problem that mortar is not fully filled.

  The reinforcing structure of the existing floor slab disclosed in Patent Document 2 is only for reinforcing the floor board with a plate-like member, and is not for joining the main girder and the floor board. In addition, the reinforcing structure of the existing floor slab disclosed in Patent Document 2 follows the taper when bubbles are generated in the tapered insertion hole when mortar is filled below the plate-like member. Although air bubbles can be moved and discharged upward easily, when air bubbles are generated on the lower surface of the plate-like member apart from the insertion hole, the air bubbles are accumulated on the lower surface of the plate-like member and the mortar is not sufficiently filled. There was a problem of that.

  In the joint structure of the girder and floor slab disclosed in Patent Document 3, since the lower surface of the floor slab is formed flat, air bubbles accumulate on the lower surface of the floor slab when it is filled with a time-hardening material. Since there is a possibility that the time-hardenable material may not be sufficiently filled, there is room for further improvement.

  Therefore, the present invention has been made in view of the above-mentioned problems, and the purpose of the present invention is to enable sufficient filling with time-hardening material such as mortar embedded for joining to the main girder. It is an object of the present invention to provide a precast floor slab capable of removing air bubbles and a bridge using the same.

The precast floor slab according to the first aspect of the present invention is a precast floor slab provided above the main girder, including a lower end face provided opposite to the upper flange of the main girder and a hole penetrating upward from the lower end face. The lower end face has a tapered portion which is inclined so that the height becomes higher toward the insertion axis toward the bridge axis direction of the main girder, and the tapered portion is provided in plurality in the bridge width direction, the width of the bridge width direction of the tapered section is characterized width less der Rukoto bridge width direction of the top flange.

The precast floor slab according to the second aspect of the present invention is a precast floor slab provided above the main girder, including a lower end face provided to face the upper flange of the main girder and a penetration from the lower end face upward. The lower end face has a tapered portion which is inclined so that the height becomes higher toward the insertion axis toward the bridge axis direction of the main girder, and the tapered portion A plurality of the holes are provided in the bridge width direction, and the insertion holes are spaced apart in the bridge axis direction, and one of the tapered portions is formed between the insertion holes and the other insertion holes adjacent in the bridge axis direction. And the other said taper part is characterized in that it is provided continuously with each other at the lower end part of the slope toward the bridge axis direction.

The precast floor slab according to the third aspect of the present invention is a precast floor slab provided above the main girder, including a lower end face provided to face the upper flange of the main girder and a penetration from the lower end face upward. The lower end face has a tapered portion which is inclined so that the height becomes higher toward the insertion axis toward the bridge axis direction of the main girder, and the tapered portion A plurality of flat portions are provided in the bridge width direction, and the lower end face has a flat portion provided between one of the tapered portions and another tapered portion adjacent in the bridge width direction, and the tapered portions are It is characterized in that the height of the lower end portion is equal to or greater than the height of the flat portion.

  In the precast floor slab according to the fourth invention, in the first invention to the third invention, the insertion hole has an upper end side opening formed on the upper end side and a lower end side opening formed on the lower end side. The upper end side opening portion is formed to have a diameter larger than that of the lower end side opening portion.

  The bridge according to the fifth invention is a bridge provided with a main girder, and the precast deck slab according to the first invention to the fourth invention is attached above the main girder.

  According to the first to fourth inventions, when air bubbles naturally mixed in the surface etc. are generated at the time of filling of the time-hardenable material, the tapered portion is inclined so as to increase in height as it approaches the insertion hole. Since it is formed, it becomes possible to move air bubbles from the low side to the high side of the height of the tapered portion as the time-hardening material is filled.

  According to the first to fourth inventions, the tapered portion inclined in the direction of the bridge axis is provided at the lower end side opening of the insertion hole formed at an interval in the bridge axis direction, so that the air bubble is inserted It is possible to reach the holes and remove air bubbles, and it is possible to sufficiently fill the time-curable material.

  According to the second invention, in particular, a plurality of insertion holes are provided at intervals in the bridge axis direction, and each of the tapered portions formed between the insertion holes adjacent in the bridge axis direction is in the bridge axis direction By continuously providing each other at the lower end of the facing slope, even if air bubbles are generated anywhere such as the surface of the time-hardening material, the air bubbles are brought into contact with the tapered portion as the time-hardening material is filled. It can be done.

  Further, according to the second aspect of the invention, in particular, the air bubble can be moved along the tapered portion, and can be discharged toward the insertion hole.

  According to the third aspect of the invention, in particular, by providing the lower end of the tapered portion with a height equal to or greater than the height of the flat portion, bulking in the height direction is prevented when being transported and stored in stacks. Space saving can be realized.

  Further, according to the third aspect of the present invention, especially when transported or stored, the flat portion formed in the flat shape is formed at the lowermost position, so that the stable state can be maintained and stacked, which is safe. It is possible to improve the quality.

  According to the fourth invention, in particular, it is possible to easily remove the form for providing the insertion hole from the lower side to the upper side after the completion of the placement. Further, according to the fourth aspect of the invention, it is possible to improve the resistance to pulling out.

  According to the fifth aspect of the invention, in particular, when the insertion hole of the precast floor slab is filled with the time-hardening material, the filling can be performed so that the lower end surface is penetrated by forming the tapered portion. It is possible to improve the displacement rigidity between the precast floor slab and the time-hardening material.

1 is a perspective view showing a first embodiment of a bridge to which the present invention is applied. BRIEF DESCRIPTION OF THE DRAWINGS It is a front view which shows the state which looked at 1st Embodiment of the bridge to which this invention is applied from the bridge shaft direction orthogonal to the bridge width direction. It is a perspective view which shows the main girder among 1st Embodiment of the bridge to which this invention is applied. It is a front view which shows the state which looked at the main girder from the bridge shaft direction among 1st Embodiment of the bridge to which this invention is applied. BRIEF DESCRIPTION OF THE DRAWINGS It is a side view which shows the state which looked at 1st Embodiment of the bridge to which this invention is applied from the bridge width direction. It is a perspective view which shows the state which looked at the precast floor slab to which this invention is applied from the downward direction. It is a perspective view which shows the state which looked at the modification of the precast floor slab to which this invention is applied from the downward direction. It is a perspective view which shows the state which looked at the precast floor slab and the main girder to which this invention is applied from the downward direction. It is a bottom view which shows the state which looked at the precast floor slab to which this invention is applied from the downward direction. It is a side view which shows the state which looked at the precast floor slab to which this invention is applied from the bridge width direction. It is a side view which shows the state which looked at the precast floor slab to which this invention is applied from the bridge width direction. It is a side view which shows the state which looked at the precast floor slab to which this invention is applied from the bridge width direction. It is a side view which shows the state which looked at the precast floor slab to which this invention is applied from the bridge width direction. (A) is a top view which shows the state which looked at the insertion hole of the precast floor slab which applied this invention from upper direction, (b) is a side view which shows the state which looked at it from the bridge width direction, (C) is a front view which shows the state which saw it from the bridge shaft direction, (d) is a top view which shows the state which looked at the modification from the upper direction. It is a side view which shows the state which is filling the time-hardenable material from the insertion hole of the precast floor slab to which this invention is applied toward the upper end surface of the upper flange of the main girder from the bridge width direction. It is a perspective view which shows 2nd Embodiment of the bridge to which this invention is applied. It is a perspective view which shows the main girder among 2nd Embodiment of the bridge to which this invention is applied. It is a front view which shows the state which looked at 2nd Embodiment of the bridge to which this invention is applied from the bridge shaft direction. It is a side view which shows the state which looked at 2nd Embodiment of the bridge to which this invention is applied from the bridge width direction. (A) is a sectional side view which shows the state which looked at the example of this invention from the bridge width direction, (b) is a front sectional view which shows the state which looked at the example of this invention from the bridge shaft direction. (A) is a side cross-sectional view which shows the state which looked at the comparative example from the bridge width direction, (b) is a front sectional view which shows the state which looked at the comparative example from the bridge shaft direction. The results of loading tests conducted using the inventive example are shown, and (a) shows the relationship between the loading load until failure of the test body and the deflection at the center of the main girder span, (b) These are figures which showed the relationship between the load of a load before the shear failure which is a failure | damage of a joint surface arises, and the bending of the center between the support of a main girder. The results of the loading test using the comparative example are shown, and (a) shows the relationship between the loading load until failure of the test body and the central deflection of the main girder, (b) FIG. 6 is a view showing a relationship between a load applied before occurrence of displacement failure, which is a failure of a joint surface, and a deflection at the center of a span of a main girder.

  Hereinafter, an embodiment for implementing a bridge to which the present invention is applied will be described in detail with reference to the drawings.

  FIG. 1 is a perspective view showing a first embodiment of a bridge 1 to which the present invention is applied. The bridge 1 to which the present invention is applied is mainly used in the case of construction as a new construction or in the case of construction as an existing replacement.

  As shown in FIG. 1, in the first embodiment, the bridge 1 is, in particular, a main girder 30 juxtaposed with a gap in the bridge width direction Z and a flat precast provided above the main girder 30. A floor slab 40 and a time-hardening material 50 provided between the main girder 30 and the precast floor slab 40 are provided.

  The main girder 30 is provided above a bridge pier or an abutment. The main girder 30 is made of precast concrete having a web 33 between the upper flange 31 and the lower flange 32. The main girder 30 is not limited to this, and precast prestressed concrete may be used. The main girder 30 is formed, for example, to have a substantially I-shaped cross section. The main girder 30 is not limited to a substantially I-shaped cross section, but may have a substantially T-shaped cross section or the like, and is not limited to that shape.

  FIG. 2 is a front view showing a state in which the bridge 1 to which the present invention is applied is viewed in the bridge axial direction X orthogonal to the bridge width direction Z. As shown in FIG.

  As the main girder 30 is shown in FIG. 2, the dimension of the upper flange 31 in the bridge width direction Z is formed by the width dimension Wf. The main girder 30 is provided with a stirrup 37 composed of reinforcing bars and the like in the bridge width direction Z, and a main reinforcement 36 composed of reinforcing bars and the like is arranged so as to intersect the stirrups 37. The main girder 30 may be provided with other reinforcing bars, but is not shown.

  The main girder 30 is a sealing material 61 for preventing leakage of the time-hardening material 50 filled between the upper end surface 31 a of the upper flange 31 and the lower end surface 41 of the precast floor plate 40 before curing. May be provided. As the sealing material 61, an elastic body having water proofness such as rubber is used. The sealing material 61 may be provided at the edge of the upper end surface 31 a of the upper flange 31.

  FIG. 3 is a perspective view showing the main girder 30. As shown in FIG. FIG. 4 is a front view showing the main girder 30 as viewed from the bridge axis direction X. As shown in FIG.

  As shown in FIG. 3, the main girder 30 is provided with a displacement prevention member 34 formed of a reinforcing bar or the like from the upper end surface 31 a of the upper flange 31 at intervals in the bridge axis direction X which is the longitudinal direction. The main girder 30 is provided horizontally in the bridge axis direction X.

  In the main girder 30, the upper end surface 31a of the upper flange 31 is formed as a rough surface by the washing process. The washing process is a so-called surface roughening process, and for example, the surface roughness is previously adjusted to a predetermined level by bringing a chemical solution or the like into contact. In fact, in this washing-out process, it is possible to apply a surface roughening treatment by, for example, spraying a hardening retarding agent and washing it out with high-pressure washing water. Besides, as a method of surface roughening, a resin sheet with rigid irregularities is attached to the surface of the formwork before casting, and after hardening the concrete, the surface is removed by removing the sheet at the same time as forming a rough surface. It may be done. The sheet is embossed to form asperities, and is made of, for example, polypropylene resin. Roughening by this method is referred to as roughening with an embossed resin sheet.

  The anti-slip member 34 is embedded in and fixed to the main girder 30 as shown in FIG. 4 (a). The anti-slip member 34 includes a longitudinal member 34a formed by projecting upward from the upper end surface 31a of the upper flange 31 and a cross member 34b formed by extending from the upper end of the longitudinal member 34a in the bridge width direction Z It is formed.

  As shown in FIG. 4B, the anti-slip member 34 may be formed of only the longitudinal members 34a, and the configuration of the cross members 34b may be omitted. As shown in FIG. 4C, the longitudinal members 34a may be formed at both ends of the cross member 34b in the bridge width direction Z, respectively.

  The anti-slip member 34 is not limited to this, and may be formed in any shape. The anti-slip member 34 may be provided so as to project from the upper end surface 31 a of the upper flange 31 in any quantity.

  As shown in FIG. 1, a plurality of precast floor slabs 40 are provided side by side at intervals in the bridge axis direction X. The precast floor slab 40 is provided with a cast-in-place joint 63 made of cast-in-place concrete that is filled to fill the space between the precast floor slab 40 adjacent in the bridge axis direction X of the main girder 30. In the precast floor slab 40, main bars 49 are disposed in the bridge axial direction X.

  The precast floor slab 40 is disposed to make all of the floor slabs precast, not so-called on-site casting where concrete is cast on site.

  FIG. 5 is a side view showing the bridge 1 to which the present invention is applied as viewed from the bridge width direction Z. As shown in FIG. The precast floor slab 40 has a lower end surface 41 provided to face the upper end surface 31 a of the upper flange 31 of the main girder 30 and an insertion hole 42 formed to penetrate upward from the lower end surface 41 in the height direction Y. And side portions 43 formed on both ends of the lower end surface 41 in the bridge axis direction X.

  FIG. 6 is a perspective view showing a precast floor slab 40 to which the present invention is applied, viewed from below.

  As shown in FIG. 6, the lower end surface 41 is formed to be flat and tapered such that the height thereof becomes higher toward the insertion hole 42 toward the bridge axis direction X and is formed into a planar shape, and one tapered portion A flat portion 44 is provided between 45 and another tapered portion 45 adjacent in the bridge width direction Z.

  The lower end surface 41 is provided apart from the upper end surface 31 a of the upper flange 31 as shown in FIG. 2.

  The tapered portion 45 is roughened by a washout process or an embossed resin sheet. The tapered portion 45 is not limited to this, and may be formed in a smooth shape in which a configuration to be a rough surface is omitted.

  As shown in FIG. 6, the tapered portion 45 has an upper end 45 a which is the upper end of the inclined taper 45 in the bridge axial direction X and a lower end 45 b which is the lower end of the inclined tapered 45. . The tapered portion 45 is formed such that the height of the upper end portion 45 a thereof is substantially the same as the height of the flat portion 44. The tapered portion 45 is continuously provided with another tapered portion 45 adjacent in the bridge axis direction X at the lower end portion 45 b thereof.

  FIG. 7 is a perspective view showing a modified example of the precast floor slab 40 to which the present invention is applied, viewed from below. The tapered portion 45 is not limited to this, and as shown in FIG. 7, the upper end 45a is positioned above the height of the flat portion 44, and the height of the lower end 45b is substantially the same as the height of the flat portion 44. It may be configured to

  In addition, although not shown, for example, the tapered portion 45 may be formed such that the height of each of the upper end portion 45 a and the lower end portion 45 b is located above the height of the flat portion 44. . The tapered portion 45 may be formed such that the heights of the upper end portion 45 a and the lower end portion 45 b are respectively located below the height of the flat portion 44. Further, the tapered portion 45 may be formed such that the height of the upper end portion 45 a is located above the flat portion 44 and the height of the lower end portion 45 b is located below the flat portion 44.

  FIG. 8 is a perspective view showing the precast floor slab 40 to which the present invention is applied and the main girder 30 as viewed from below.

  As shown in FIG. 8, the tapered portion 45 is formed such that the width dimension Wt which is the dimension in the bridge width direction Z is substantially the same as the width dimension Wf of the upper flange 31 of the main girder 30. The width dimension Wt is not limited to this, and is not limited to being substantially the same as the width dimension Wf.

  FIG. 9 is a bottom view showing the precast floor slab 40 to which the present invention is applied, viewed from below.

  The tapered portion 45 is formed in a rectangular shape as viewed from below as shown in FIG. The tapered portions 45 are provided in a plurality in a row in the bridge width direction Z.

  Fig.10 (a) is a side view which shows the state which looked at the precast floor slab 40 to which this invention is applied from the bridge width direction Z, and FIG.10 (b), FIG.11, FIG.12 and FIG. It is a figure which shows an example.

  As shown in FIG. 10A, the tapered portion 45 is formed such that its height decreases with distance from the insertion hole 42 in the bridge axial direction X, and the gradient thereof changes upward at the lower end 45b. The lower end 45b is formed to be sharpened, and is formed to be higher in height as it approaches another adjacent insertion hole 42.

  The tapered portion 45 is formed to be inclined at an inclination angle θ which is an angle formed by the horizontal direction and the inclination with respect to the bridge axis direction X extending in the horizontal direction. Although it is desirable that the inclination angle θ be formed at 5 ° or more, it is not limited thereto, and may be formed at any angle. The length of the tapered portion 45 is formed by an oblique distance S which is a distance in the extension direction of the inclined portion in the bridge axial direction X.

  The tapered portion 45 is not limited to this, and as shown in FIG. 10 (b), the height is reduced in the bridge axial direction X as it goes away from the insertion hole 42, and the slope thereof is substantially reduced at the lower end 45b. It may be formed to change in the horizontal direction and to increase in height as it approaches other adjacent insertion holes 42. At this time, the tapered portion 45 is provided with a horizontal portion 46 formed extending in a substantially horizontal direction at the lower end portion 45 b.

  The tapered portion 45 is not limited to this, and may be formed by stepwise changing the gradient formed in a plane. That is, as shown in FIG. 11A, the tapered portion 45 is an angle formed with respect to the bridge axial direction X with respect to the tapered portion 45-1 formed by the inclined angle θ1 which is an angle formed with respect to the bridge axial direction X. A tapered portion 45-2 formed at an angle θ2 and a slope changing portion P1 in which the slope of the tapered portion 45-1 and the tapered portion 45-2 changes. At this time, the inclination angle θ1 is formed at an angle larger than the inclination angle θ2.

  As shown in FIG. 11B, the tapered portion 45 may be formed at an inclination angle θ1 smaller than the inclination angle θ2.

  The length of the tapered portion 45 is, in FIGS. 11A and 11B, an oblique distance S1 which is the distance in the extension direction of the inclined portion in the bridge axis direction X of the tapered portion 45-1, and the tapered portion 45-2. And an oblique distance S2 which is a distance in the extension direction of the inclined portion in the bridge axis direction X of At this time, although it is desirable that the oblique distance S1 be substantially the same as the oblique distance S2, the present invention is not limited to this, and the oblique distance S1 is not limited by the magnitude relation with the oblique distance S2.

  As shown in FIG. 12A, the tapered portion 45 may have a plurality of gradient change portions P. That is, the taper part 45 may have n gradient change parts P1, P2... Pn (n is a natural number). At this time, the tapered portion 45 is formed of tapered portions 45-1, 45-2, ..., 45-i, ... 45-n + 1. A certain tapered portion 45-i is formed to be inclined at an inclination angle θi which is an angle formed with respect to the bridge axis direction X (i is a natural number of 1 or more and n + 1 or less). At this time, the inclination angle θi is formed to be always larger than the inclination angle θi + 1. The height of the gradient change portion Pi is formed to be always higher than the height of the gradient change portion Pi + 1.

  In the case described above, the length of the tapered portion 45-i is formed by the oblique distance Si which is the distance in the extension direction of the inclined portion in the bridge axis direction X. At this time, although it is desirable that the oblique distance Si be substantially the same as the oblique distance Sk different from the oblique distance Si, the present invention is not limited thereto, and the oblique distance Si is not limited by the magnitude relationship with the oblique distance Sk. (K is a natural number different from i and not less than 1 and not n + 1).

  Further, when the taper portion 45 has n gradient change portions P1, P2,... Pn, the inclination angle θi of a certain taper portion 45-i is inclined as shown in FIG. 12 (b). It may be formed to be always smaller than the angle θi + 1.

  The taper portion 45 is not limited to a flat shape, and may be formed into a curved surface shape in which the gradient changes continuously as shown in FIG. 13 (a). At this time, the tangent of the curved surface in the insertion hole 42 is formed at the inclination angle θ, and the slope thereof becomes smaller as it gets away from the insertion hole 42, and the taper portion 45 is formed substantially horizontally at the lower end 45b. .

  Alternatively, when the tapered portion 45 is formed in a curved shape as shown in FIG. 13B, a tangent of the curved surface is formed at the inclination angle θ at the lower end 45b, and the inclination thereof approaches the insertion hole 42 Is smaller and formed substantially horizontally in the insertion hole 42. At this time, the lower end 45 b may be provided with a horizontal portion 46 which is formed to extend substantially in the horizontal direction.

  The flat portion 44 may be formed at an end of the lower end surface 41 in the bridge width direction Z, as shown in FIG. The flat portion 44 is formed in a smooth shape in which the configuration to be a rough surface is omitted.

  The insertion holes 42 are provided above the upper flanges 31 of the plurality of main girder 30 provided at intervals in the bridge width direction Z, as shown in FIG. 1. The insertion holes 42 may be provided in any quantity in the bridge width direction Z in accordance with the arrangement quantity of the main girder 30.

  The insertion holes 42 are provided in plurality at intervals in the bridge axial direction X, as shown in FIG. 5. The insertion holes 42 may be provided in any quantity in the bridge axial direction X. The insertion hole 42 is provided with a tapered portion 45 between another insertion hole 42 adjacent in the bridge axial direction X.

  The anti-slip member 34 is inserted into the inside of the insertion hole 42. The insertion hole 42 has an upper end side opening 42a formed on the upper end side, a lower end side opening 42b formed on the lower end side, and an inner surface formed between the upper end side opening 42a and the lower end side opening 42b. It has the part 42c.

  The insertion hole 42 is formed such that the upper end side opening 42 a is larger in diameter than the lower end side opening 42 b and vertically penetrates. The insertion hole 42 is filled with a time-hardening material 48 whose main component is cement or the like.

  FIG. 14 (a) is a plan view showing the insertion hole 42 viewed from above, and FIG. 14 (b) is a side view showing the insertion hole 42 viewed from the bridge width direction Z. 14 (c) is a front view showing the insertion hole 42 as viewed in the bridge axial direction X. FIG. FIG. 14D is a plan view showing a modification of the insertion hole 42 as viewed from above.

  As shown in FIG. 14A, the upper end side opening 42a is formed by a major axis La which is a dimension in the bridge width direction Z and a minor axis Ma which is a dimension in the bridge axis direction X. The lower end side opening 42b is formed with a major axis Lb which is a dimension of the bridge width direction Z and a minor axis Mb which is a dimension of the bridge axis direction X.

  The upper end side opening 42a is formed such that its minor diameter Ma is equal to or more than the minor diameter Mb of the lower end side opening 42b as shown in FIG. 14 (b), and as shown in FIG. 14 (c) It is preferable that the major diameter La is formed to be equal to or larger than the major diameter Lb of the lower end side opening 42b, but the present invention is not limited to this.

  For example, the upper end side opening 42a may have a minor diameter Ma equal to or greater than the minor diameter Mb of the lower end side opening 42b, and a major diameter La may be substantially the same as the major diameter Lb of the lower end side opening 42b. Besides, the upper end side opening portion 42a is formed such that the minor diameter Ma thereof is substantially the same as the minor diameter Mb of the lower end side opening portion 42b, and the major diameter La thereof is equal to or greater than the major diameter Lb of the lower end side opening portion 42b. May be

  The upper end side opening 42a and the lower end side opening 42b are formed in a long hole shape when viewed from the upper side, as shown in FIG. 14 (a). The upper end side opening 42a and the lower end side opening 42b are not limited to this, and may be formed in a circular shape. The upper end side opening 42a and the lower end side opening 42b are not limited to the long hole shape, and may be formed in a square shape as shown in FIG. 14 (d), and the shape is not limited to that.

  The lower end side opening 42b is provided such that the major diameter Lb is smaller than the width dimension Wf of the upper end surface 31a of the upper flange 31 in the bridge width direction Z, as shown in FIG. The lower end side opening 42 b is provided at the upper end 45 a of the tapered portion 45 as shown in FIG. 6.

  As shown in FIGS. 14 (b) and 14 (c), the inner surface portion 42c is formed to be reduced in diameter and inclined at the same inclination from the upper end side opening 42a to the lower end side opening 42b. The inner surface portion 42c is not limited to this, and may be formed so as to change the inclination of the inclination. The inner surface portion 42c is not limited to this, and may be formed in a curved shape.

  As shown in FIG. 6, the side surface portion 43 is provided such that a main reinforcement 49 made of a reinforcing bar or the like protrudes in the bridge axial direction X. The main bar 49 may be coated with an epoxy resin. The reinforcement bars 49 a may be attached to the ends of the main bars 49 for improving adhesion with the cast-in-place joints 63. The reinforcing member 49a is made of metal such as steel. Although not shown, the main reinforcement 49 may be protruded from the side surface 43 in the bridge axial direction X, formed in a semicircular shape in the middle thereof, and extended to the side surface 43.

  The time-hardening material 48 is a material such as mortar, grout, concrete which is hardened by hydration, or the like, which is hardened when a certain time passes. The time-hardening material 48 may be an expansible cement-based material.

  The time-hardening material 50 is filled between the upper end surface 31 a of the upper flange 31 of the main girder 30 and the lower end surface 41 of the precast floor plate 40 as shown in FIG. 4. The time-hardenable material 50 can be filled as a substitute for the time-hardenable material 48.

  The time-hardening material 50 is a material such as a non-shrink mortar, a non-shrink grout, or the like that hardens due to hydration reaction or the like, and which hardens after a predetermined time passes. As the time-hardenable material 50, desirably, a cement-based material having high flowability is selected.

  FIG. 15 is a side view showing a state in which the time-hardenable material 50 is filled from the insertion holes 42 of the precast floor slab 40 to which the present invention is applied toward the upper end surface 31 a of the upper flange 31 from the bridge width direction Z. .

  In the precast floor slab 40 to which the present invention is applied, as shown in FIG. 15, when air bubbles 80 are naturally mixed in the surface etc. at the time of filling of the time-hardening material 50, the tapered portion 45 is inserted into the insertion hole 42. As it is formed to be inclined so as to increase in height as it approaches, as the time-hardening material 50 is filled, the air bubbles 80 are directed in the direction of the arrows in FIG. It becomes possible to move to the higher side.

  At this time, in the precast floor slab 40 to which the present invention is applied, the lower end side opening 42b of the insertion hole 42 in which the tapered portion 45 inclined toward the bridge axial direction X is formed with a space in the bridge axial direction X. Thus, the air bubble 80 can reach the insertion hole 42.

  For this reason, the precast floor slab 40 to which the present invention is applied can cause the air bubbles 80 generated on the surface, etc. to reach the insertion holes 42 by filling the time-hardenable material 50, and the air bubbles 80 can be removed. It will be possible. Therefore, the precast floor slab 40 to which the present invention is applied can be sufficiently filled with the time-hardenable material 50.

  In the precast floor slab 40 to which the present invention is applied, each of the tapered portions 45 formed between the insertion holes 42 adjacent to each other in the bridge axial direction X has the insertion holes 42 spaced apart from each other in the bridge axial direction X By continuously providing the lower end 45b of the slope toward the bridge axial direction X, even if the air bubbles 80 are generated anywhere on the surface of the time-hardenable material 50, the filling of the time-hardenable material 50 Accordingly, the air bubble 80 can be brought into contact with the tapered portion 45.

  For this reason, the precast floor slab 40 to which the present invention is applied can move the air bubbles 80 along the tapered portion 45 when the time-hardening material 50 is filled therebelow, It becomes possible to discharge.

  In the precast floor slab 40 to which the present invention is applied, as shown in FIGS. 12A and 12B, when the tapered portion 45 is formed with a plurality of gradient change portions P, the height of the gradient change portions Pi is It is formed to be always higher than the height of the gradient change portion Pi + 1.

  As a result, when the precast floor slab 40 to which the present invention is applied is filled with the time-hardening material 50 below, the air bubbles 80 can be moved along the tapered portions 45 and directed to the insertion holes 42. It becomes possible to discharge.

  In the precast floor slab 40 to which the present invention is applied, when the time-hardening material 50 is filled therebelow, the tapered portion 45 is formed as a rough surface, so that the air bubbles 80 are formed between the irregularities of the rough surface. Can be moved along the tapered portion 45 and can be discharged toward the insertion hole 42.

  In the bridge 1 to which the present invention is applied, when the main girder 30 made of concrete and the precast floor slab 40 are joined, the upper end face 31a of the upper flange 31 and the tapered portion 45 are formed as rough surfaces. .

  At this time, in the bridge 1 to which the present invention is applied, the lower end surface 41 of the precast floor slab 40 is separated from the upper flange 31 of the main girder 30 to form a void, and the void is filled with the temporal curing material 50.

  Thereby, the bridge 1 to which the present invention is applied can engage the time-hardening material 50 with the unevenness of the rough surface, and the taper surface 45 of the precast floor slab 40 and the upper end surface 31a of the upper flange 31 harden over time. It can be firmly fixed to the material 50, and the shear shear resistance can be improved.

  Since the precast floor slab 40 to which the present invention is applied is made of precast, it is necessary to transport it from a factory to a construction site and store it near a construction site which is spatially limited until construction.

  For this reason, it is necessary to stack the precast floor slabs 40 to which the present invention is applied when the transportation to the construction site or storage near the construction site is performed. When the precast floor slab 40 to which the present invention is applied is stacked and transported or stored by providing the lower end 45b of the tapered portion 45 with a height equal to or greater than the height of the flat portion 44, in the height direction Y Can be prevented, and space saving can be realized.

  In addition, the precast floor slab 40 to which the present invention is applied can be stacked and maintained in a stable state by forming the flat surface portion 44 formed in the lowermost position when being transported or stored. It is possible to improve safety.

  When the precast floor slab 40 to which the present invention is applied is manufactured in a factory or the like, concrete is cast after the formwork for providing the insertion holes 42 is installed in advance. Therefore, in the precast floor slab 40 to which the present invention is applied, the upper end side opening 42a of the insertion hole 42 is formed to be larger in diameter than the lower end side opening 42b and penetrated in the vertical direction. It is possible to easily remove the formwork for providing the insertion holes 42 from the lower side to the upper side after the installation is completed.

  Further, as shown in FIG. 5, in the precast floor slab 40 to which the present invention is applied, the upper end side opening 42a of the insertion hole 42 is formed to have a diameter larger than that of the lower end side opening 42b and penetrated vertically. Since the inner surface portion 42c is locked to the hardened material 48 which hardens over time when the force of being pulled upward acts, the resistance to pulling can be improved.

  Next, as shown in FIG. 16, in the second embodiment, the bridge 1 to which the present invention is applied is, in particular, a main girder 70 made of metal such as steel and a precast floor provided above the main girder 70 The case of providing the version 40 will be described. In addition, about the component same as the component mentioned above, the following description is abbreviate | omitted by attaching the same code | symbol.

  The main girder 70 has a web 73 between the upper flange 71 and the lower flange 72, and a steel material such as H-shaped steel is used. The main girder 70 is formed to have, for example, a substantially I-shaped cross section. Not only this but the main girder 70 may be formed in any shape.

  FIG. 17 is a perspective view showing the main girder 70. As shown in FIG. In the main girder 70, the upper end surface 71a of the upper flange 71 is formed in a smooth shape in which the configuration as a rough surface is omitted. In the main girder 70, a shift prevention member 74 configured of a stud dowel or the like from the upper end surface 71a of the upper flange 71 is provided at an interval in the bridge axial direction X.

  The anti-slip member 74 is formed to project from the upper end surface 71 a of the upper flange 71. The anti-slip member 74 is provided with a head 74 a at its upper end. The configuration of the head 74a may be omitted.

  FIG. 18 is a front view showing a state in which the second embodiment of the bridge 1 to which the present invention is applied is viewed from the bridge axial direction X. FIG. FIG. 19 is a side view showing a second embodiment of the bridge 1 to which the present invention is applied, as viewed from the bridge width direction Z. As shown in FIG.

  In the precast floor slab 40, as shown in FIG. 18, the anti-slip member 74 constituted of a stud dowel or the like attached by protruding from the upper end surface 71a of the upper flange 71 of the main girder 70 is inserted into the insertion hole 42 from below. Be inserted.

  As shown in FIG. 19, the precast floor slab 40 is provided with the lower end portion 45 b of the tapered portion 45 above the upper end surface 71 a of the upper flange 71 of the main girder 70. The time-hardenable material 48 is filled between the lower end 45 b of the tapered portion 45 of the precast floor slab 40 and the upper end surface 71 a of the upper flange 71 of the main girder 70 and the inside of the insertion hole 42. The precast floor slab 40 is formed in a smooth shape in which the lower end surface 41 is roughened and the structure is omitted.

  In the second embodiment of the bridge 1 to which the present invention is applied, the tapered portion 45 is formed when the insertion hole 42 of the precast floor slab 40 is filled with the time-hardenable material 48, whereby the lower end surface 41 is formed. It can be filled in such a way as to get in.

  Therefore, in the second embodiment of the bridge 1 to which the present invention is applied, the shift rigidity between the precast floor slab 40 and the time-hardenable material 48 can be improved by providing the taper portion 45 on the precast floor slab 40. It becomes possible.

  As mentioned above, although the example of the embodiment of the present invention was explained in detail, any of the above-mentioned embodiments only shows the example of the embodiment in the case of carrying out the present invention. The scope should not be interpreted in a limited manner.

  Hereinafter, the example which confirmed that the bridge 1 to which this invention is applied has sufficient shear shear resistance between a girder and a floor slab is described.

  The loading test was performed on the bridge 1 to which the present invention is applied, and the shear strength of the floor slab and the girder was confirmed from the relationship between the load and the deflection at the center of the span of the girder.

  As shown in Table 1 below, the test pieces were manufactured to have different tapers on the lower surface of the floor slab.

  Fig.20 (a) is a side sectional view which shows the state which looked at the example of this invention from the bridge width direction Z, FIG.20 (b) is a positive cross section which shows the state which looked at the example of this invention from the bridge axis direction X FIG. Fig.21 (a) is a side sectional view which shows the state which looked at the comparative example from the bridge width direction Z, FIG.21 (b) is a front sectional view which shows the state which looked at the comparative example from the bridge axial direction X. is there.

  In the example of the present invention, the main girder 30 using precast prestressed concrete, the precast floor slab 40 provided above the main girder 30, and the time-hardenable material 50 between the main girder 30 and the precast floor slab 40 Equipped with

  The main girder 30 is disposed such that the main reinforcement 36 extends in the bridge axial direction X, and the stirrup 37 is disposed to intersect the main reinforcement 36. The upper end surface 30a of the main girder 30 is washed out with a surface treatment agent and formed rough. In the main girder 30, two steel rods 39 for prestressing are arranged in the bridge axial direction X. The diameter of the steel rod 39 is 32 mm, and the diameter of the sheath tube is 38 mm. On the upper end surface 30 a of the main girder 30, anti-slip members 34 are arranged at intervals in the bridge axial direction X.

  As the anti-slip member 34, a steel rod for reinforced concrete D10 of SD295A defined by Japanese Industrial Standard (JIS G 3112) is used. The anti-slip member 34 is disposed so that the ratio of the cross-sectional area of the anti-slip member 34 to the area of the upper end surface 30a of the main girder 30, that is, the so-called anti-slip bar ratio (reinforcement bar ratio) becomes 0.2%. .

  The lower surface 41 of the precast floor slab 40 is formed to be rough. The precast floor slab 40 is provided so that the anti-slip member 34 is inserted into the insertion hole 42 from below and is opposed to the upper end surface 30 a of the main girder 30.

  In the example of the present invention and the comparative example, in the space formed between the upper end surface 30a of the main girder 30 and the lower end surface 41 of the precast floor plate 40, the time-hardening material 50 made of non-shrink mortar from the insertion hole 42 Be filled. In the present invention example and the comparative example, the lower joint surface in contact with the upper end surface 30a of the main girder 30 and the lowermost layer of the temporal curing material 50, and the uppermost layer of the temporal curing material 50 at the lower end surface 41 of the precast floor plate 40 It joins by having the upper joint surface which contacts.

  In the example of the present invention and the comparative example, a time-hardening material 48 made of expansive concrete is placed inside the insertion hole 42.

  In particular, as shown in FIG. 20 (a), the height of the lower end surface 41 of the precast floor slab 40 becomes higher toward the bridge axial direction X of the main girder 30 as it approaches the insertion hole 42, as shown in FIG. In particular, it is formed to have a slope of 5% and is joined to the main girder 30.

  In the comparative example, particularly, as shown in FIG. 21 (a), the configuration of the tapered portion 45 is omitted at the lower end surface 41 of the precast floor slab 40, and the main girder has only the flat portion 44 roughened. It is joined with 30.

  FIG. 22 shows the results of the loading test conducted using the inventive example, where (a) shows the loading load until the breakage of the test body and the deflection of the center of the main girder 30 (D3 in the legend in the figure). (B) shows the relationship between the load applied to the joint surface and the deflection (D3) at the center of the support of the main girder 30 before the occurrence of the shear failure. is there. Misalignment failure is a failure in the upper joint surface or the lower joint surface.

Moreover, FIG. 23 is the result of having carried out the loading test using a citation example. Of the legend shown in FIGS. 22 and 23, the safety Ritsuna (50 N / mm ^2), in case design strength of the concrete is 50 N / mm ^2, Land, Specifications for Highway Bridges defined by DOT (2012 It shows the value obtained by dividing the allowable value shown in fiscal year) by the safety factor of 1.7.

In the example of the present invention, as shown in FIG. 22, after the loading load exceeds no safety factor (50 N / mm ² ), the shear failure occurs. After that, in the example of the present invention, the yield strength decreased due to the compression failure of the main girder 30.

  On the other hand, in the comparative example, as shown in FIG. 23, the shift failure occurred near the point where the load applied exceeded 200 kN. In the comparative example, since the main girder 30 and the precast floor slab 40 themselves were not broken, the load increased when the loading was continued, and finally the shear failure of the main girder 30 occurred, and the yield strength decreased.

  From the above, it was confirmed that the example of the present invention has a shear shear resistance superior to that of the cited example because the shear failure occurs at a load load larger than that of the cited example. This is because the example of the present invention has the tapered portion 45 on the lower end surface 41 of the precast floor slab 40, so that when the time-hardenable material 50 is filled, air stagnation etc. can be removed and the internal air is pushed out. It was surmised that the main girder 30 and the precast floor slab 40 would be more firmly joined because they would be filled.

  Further, in the example of the present invention, since the load failure is greater than the value obtained by dividing the allowable value shown in the road bridge specification (2012) by the safety factor 1.7, the shear failure occurs, so that the excellent shear shear resistance is obtained. It was suggested to have

1: Bridge 30, 70: Main girder 30a, 31a, 71a: Upper end face 31, 71: Upper flange 32, 72: Lower flange 33, 73: Web 34, 74: Slip prevention member 34a: Vertical member 34b: Horizontal member 36 , 49: main reinforcement 37: stirrup 39: steel rod 40: precast floor plate 41: lower end surface 42: insertion hole 42a: upper end side opening 42b: lower end side opening 42c: inner surface 43: side surface 44: flat surface 45 A: Tapered portion 45a: Upper end portion 45b: Lower end portion 46: Horizontal portion 48, 50: Curing material over time 49a: Reinforcement member 61: Sealing member 63: Cast-in-place joint portion 74a: Head 80: Bubble La, Lb: Long diameter Ma , Mb: minor axis P: slope changing portion S: oblique distance Wf, Wt: width dimension X: bridge axis direction Y: height direction Z: bridge width direction θ: inclination angle

Claims (5)

A precast floor slab provided above the main girder,
It has a lower end face provided to face the upper flange of the main girder, and an insertion hole formed to penetrate upward from the lower end face,
The lower end face has a tapered portion which is inclined so as to increase in height toward the insertion hole toward the bridge axis direction of the main girder,
The tapered portion is provided in a plurality in the bridge width direction ,
The width of the bridge width direction of the tapered portion, precast slab, characterized in width or less der Rukoto bridge width direction of the top flange. A precast floor slab provided above the main girder,
It has a lower end face provided to face the upper flange of the main girder, and an insertion hole formed to penetrate upward from the lower end face,
The lower end face has a tapered portion which is inclined so as to increase in height toward the insertion hole toward the bridge axis direction of the main girder,
The tapered portion is provided in a plurality in the bridge width direction,
The insertion holes are provided in a plurality at intervals in the bridge axial direction.
The tapered portions formed between the insertion holes adjacent to each other in the bridge axial direction are continuously provided to each other at the lower end portion of the slope toward the bridge axial direction.
Precast floor version featuring. A precast floor slab provided above the main girder,
It has a lower end face provided to face the upper flange of the main girder, and an insertion hole formed to penetrate upward from the lower end face,
The lower end face has a tapered portion which is inclined so as to increase in height toward the insertion hole toward the bridge axis direction of the main girder,
The tapered portion is provided in a plurality in the bridge width direction,
The lower end face is between one of the tapered portions and another of the tapered portions adjacent in the bridge width direction.
Having a flat part provided,
The tapered portion is formed such that the height of the lower end portion is greater than the height of the flat portion.
Precast floor version featuring. The insertion hole has an upper end side opening formed on the upper end side and a lower end side opening formed on the lower end side.
The precast floor slab according to any one of claims 1 to 3, wherein the upper end side opening is formed to have a diameter larger than that of the lower end side opening. A bridge with a main girder,
A bridge characterized in that the precast floor slab according to any one of claims 1 to 4 is mounted above the main girder.

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