JP2001049616A - Precast pc web for use in concrete bridge and prestressed concrete bridge having the pc web - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a precast PC web for use in a concrete bridge, which is reduced in weight, has high shearing buckling strength, and enables to save construction labor and to shorten a construction period, and to provide a prestressed concrete bridge having the PC web. SOLUTION: A number of PC steel products 10 are longitudinally arranged at intervals in a bridge axial direction, and the steel products are embedded and fixed in concrete 8 in a state where the almost entire length of each PC steel product 10 is directly attached to the concrete. Thus, a precast prestressed concrete web 1 obtained by applying prestress to a reinforced concrete web 11 in the vertical direction by virtue of the PC steel products 10 which are directly attached to the concrete over the almost entire length thereof, is produced. Further, the prestressed concrete web members are arranged on both sides of a bridge with respect to a direction orthogonal to a bridge axial direction, and a number of the web members are serially arranged in the bridge axial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a precast PC for a bridge main girder having a straight or curved cross section in the bridge axis direction.
A prestressed concrete bridge having a web and its PC web.

[0002]

2. Description of the Related Art Conventionally, a PC bridge using a post-tension type RC web by a cast-in-place method has been known. In the case of the post-tension type RC web, a vertical duct for inserting a PC steel wire is preliminarily placed in the web, concrete is cast, and then a PC steel wire is inserted into the RC web. The fixing is performed by an edge fixing member in a portion, for example, an upper slab or a lower slab. However, in this case, since the PC steel wire and the end fixing bracket are engaged with each other due to a large stress, the engagement with the fixing bracket is released, and the tensile force is instantaneously released. The fixing bracket may be blown off at high speed by the PC steel material. In some cases, a filler such as mortar is filled later between the PC steel and the duct, but it is difficult to confirm whether the mortar is sufficiently filled and whether the mortar is sufficiently adhered. There's a problem.

There is also known a PC bridge in which steel corrugated webs are connected by welding or the like added in the bridge axis direction instead of the concrete PC webs. Has a problem in that it cannot resist a large shear buckling strength in the vertical direction. Further, the steel web requires frequent rust prevention treatments, so that maintenance costs are increased and maintenance costs are high.

[0004]

SUMMARY OF THE INVENTION In the present invention, it is necessary to confirm whether the filler between the PC steel and the duct is sufficiently filled and whether the adhesion is sufficient as in the prior art. The purpose of the present invention is to provide a lightweight precast PC web for concrete bridges that does not need to be rust-proofed like conventional steel webs. An object of the present invention is to provide a prestressed concrete bridge using the PC web, which can reduce the weight of the girder, maintain the maintenance, durability and construction costs relatively inexpensively and reduce the burden on foundations and substructures. It is. More specifically, by reducing the weight of the web occupying about 10 to 30% of the weight of the main girder made of the box girder, the weight of the main girder can be reduced, and the effects of maintenance, durability, and cost reduction can be obtained. It is possible to reduce the burden not only on the upper structure but also on the foundation and the lower structure, and when using a curved PC web whose cross-section in the bridge axis direction is formed into a curved corrugated shape, Since the rigidity in the axial direction is low and the property of allowing elastic deformation in the bridge axis direction like an accordion occurs, the bridge axle must be within the allowable elastic deformation range of one or more units in the bridge axis direction or within the allowable elastic deformation range of the entire length. The prestress can be introduced in the same direction to improve the prestress introduction efficiency, and in the case of a curved shape such as an arc-shaped waveform, the bending rigidity is increased and the shear seat is higher than that of a flat plate of the same thickness. Because having a yield strength, and lowering for possible equivalent shear buckling strength construction costs in concrete web thickness of, for example, about 30% of conventional concrete web thickness. In addition, since it can be manufactured by on-site yard or factory manufacturing, it is possible to improve quality control, save labor in construction, and shorten the construction period. As described above, the bridge using the bent corrugated PC web such as the PCA-made PC web in the present invention has the following advantages.
(2) Cost reduction results, (3) Less maintenance,
(4) The integrity of the web concrete and the upper and lower floor slabs may be smaller than the case where the steel web and the upper and lower floor slabs are combined. (5) The curved PC (RC) ) By forming a web, the same function as a vertical stiffener can be performed in the corrugated portion, and the buckling strength is improved by increasing the bending rigidity. (6) Shear strength by introducing pretension of the vertical PC steel material And improve durability.
(7) An object of the present invention is to provide a precast PC web and a prestressed concrete bridge having a PC web, which have a good view by making the entire bridge a concrete bridge, and have almost no need for rust prevention treatment, and which is also good for the environment. Is what you do.

[0005]

In order to advantageously solve the above-mentioned problems, a precast PC web for a concrete bridge according to the first aspect of the present invention includes a concrete web for a bridge main girder that extends vertically. A large number of PC steel materials are arranged at intervals in the bridge axis direction, and are directly fixed to concrete while being directly attached to concrete over almost the entire length of the PC steel material, and are directly attached over almost the entire length. A prestress is imparted to the reinforced concrete web in the vertical direction by the PC steel material.

[0006] In the invention of claim 2, claim 1 is
The present invention is characterized in that the outer surface of the precast prestressed concrete web at the middle part in the vertical direction is a cross-sectional surface and is a curved outer surface such as a waveform in the bridge axis direction.

[0007] According to the third aspect of the present invention, the first aspect is provided.
In the invention of the precast prestressed concrete web at the upper end and lower end in the vertical direction,
An upper swelling portion and a lower swelling portion are provided, respectively. A joint member such as an upper joint reinforcing bar projecting from the upper swelling portion in a lateral direction perpendicular to the bridge axis is provided, and the lower swelling portion is provided. And a joint member formed of a lower joint reinforcing bar or the like protruding in the lateral direction perpendicular to the bridge axis.

In the invention of claim 4, the precast prestressed concrete web is provided with a number of trapezoidal angular corrugations at the end in the bridge axis direction so as to extend vertically. I do.

According to a fifth aspect of the present invention, the web extending in the longitudinal direction of the bridge is formed of a precast prestressed concrete web bent in an arcuate waveform or the like.

[0010] In the invention according to claim 6, substantially the entire length of the PC steel material arranged so as to extend in the vertical direction is directly attached to the concrete, and the PC steel material into which the pretension is introduced is vertically attached to the reinforced concrete web. A plurality of precast prestressed concrete webs, which are prestressed in the direction, are arranged on both sides in the direction perpendicular to the bridge axis, and are arranged in series in the bridge axis direction.

In the invention according to claim 7, a cast-in-place upper reinforced concrete floor slab and a lower reinforced concrete floor slab are provided on the upper and lower portions of the precast prestressed concrete web and are integrally connected. And

The invention according to claim 8 is characterized in that the outer surface of the precast prestressed concrete web at the middle part in the vertical direction is a cross-sectional surface and is a curved outer surface such as a waveform in the bridge axis direction. .

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described based on the illustrated embodiment. 1 to 6 show a precast prestressed concrete web (hereinafter, also referred to as PCA PC web) 1 according to a first embodiment of the present invention, and FIG. 2 and FIG.
Fig. 4 and Fig. 5 are longitudinal sectional front views partially cut away, and Fig. 6 is a partially cutaway side view showing an end portion.

The PC web 1 made of PCA of the first embodiment
As shown in FIG. 1, one reinforcing bar is formed by bending a U-shape to extend in the vertical direction, and includes a front vertical reinforcing bar 2 and a rear vertical reinforcing bar 3 arranged in parallel in the front-rear direction. A large number of U-shaped vertical reinforcing bars 9 are arranged in parallel at intervals in the bridge axis direction, and extend in the bridge axis direction between the front vertical reinforcing bar 2 and the rear vertical reinforcing bar 3 and are vertically spaced. A large number of front horizontal reinforcing bars 4 are arranged in parallel with each other so as to be in contact with the front vertical reinforcing bars 2 and are bound together by welding or a wire (not shown). The front vertical reinforcing bars 2 are arranged so as to be in contact with the respective rear vertical reinforcing bars 3 and are bound by welding or a wire (not shown).
On the upper part of the rear vertical reinforcing bar 3, a closed loop-shaped hoop bar 6 closed in a rectangular annular shape is arranged in parallel at intervals in the bridge axis direction, and is welded or connected to the front vertical reinforcing bar 3 and the rear vertical reinforcing bar 4. (Not shown).

A plurality of upper horizontal reinforcing bars 7 (four in the illustrated case) extending in the bridge axis direction extend in the bridge axis direction in parallel so as to abut on the inner corners of the hoop bars 6. And is bound to the hoop 6, the rear vertical reinforcing bar 3, and the front vertical reinforcing bar 2 by welding or a wire (not shown). Between the front horizontal reinforcing bars 4 and the rear horizontal reinforcing bars 5, between the vertical reinforcing bars 3, 4 adjacent in the bridge axis direction, that is, on the center line of the web member in the bridge axis direction, vertically extend, In a state where a pre-tensioned PC steel material 10 made of long PC steel strands is provided in parallel at intervals in the bridge axis direction, almost the entire peripheral surface of the PC steel material 10 is added to the concrete 8 together with the reinforcing steel. After the concrete 8 is hardened, the tension of each PC steel 10 is released and both ends of each PC steel 10 are cut, so that the PC steel 10 is embedded. In this state, a vertical prestress is applied to the concrete web 11 relatively.

At the upper end of the concrete web 11, a rectangular shape which is thicker than the thickness of the concrete web in the direction perpendicular to the bridge axis, protrudes on both sides in the direction perpendicular to the bridge axis, and extends linearly in the direction of the bridge axis. The upper swelling portion 12 is provided, and the upper swelling portion 12 enhances integration with an upper floor slab 13 described later, which is built and integrated on the upper swelling portion 12, particularly in the vertical direction and It is provided to increase the shear resistance in the direction perpendicular to the bridge axis direction.

The front vertical reinforcing bar 2 and the rear vertical reinforcing bar 3 are arranged so as to protrude from the upper surface of the upper bulging portion 12 via a joint sleeve 2a as necessary, and are stretched in the horizontal direction perpendicular to the bridge axis. An upper joint reinforcing bar 15 which is bent so as to project and is united with an upper main reinforcing bar 14 of the upper floor slab 13 in a direction perpendicular to the bridge axis by welding or a wire is provided integrally. That is, when the PCA-made PC web 1 is arranged at the end of the bridge girder, it is arranged so as to protrude toward the center in the bridge girder width direction (direction perpendicular to the bridge axis), and when it is arranged at the center of the bridge girder. One end of the vertical reinforcing bar 2 on the front side is disposed so as to project to one side (front side) in the direction perpendicular to the bridge axis, and the upper end overhang of the vertical reinforcing bar 3 on the rear side is the other end in the direction perpendicular to the bridge axis. Side (rear side). In addition, as shown in FIG. 4, an upper intermediate reinforcing bar 16 is provided at an intermediate portion of the
Is fixedly embedded in the concrete 8, and one end of the upper intermediate reinforcing bar 16 is connected and fixed so that one end of the reinforcing metal connection bracket 17 is embedded in the concrete 8, and is fixed to the other end of the reinforcing steel connection bracket 17. The other ends of the connected reinforcing bar and the upper intermediate reinforcing bar 16 project from the bulging portion 12 to form a dowel bar 16a.

As shown in FIG. 4, the lower end of the concrete web 11 extends in the bridge axis direction,
A lower projecting portion (lower projecting portion) 18 protruding in one direction perpendicular to the bridge axis is provided. In the projecting portion 18, an upper vertical portion 19 and an inclined portion 20 vertically arranged below the rear vertical reinforcing bar 3. In addition, a base side of a reinforcing bar 24 for reinforcing a haunch portion having a lower horizontal portion 22 bound to a lower reinforcing bar 21 in a direction perpendicular to the bridge axis in the lower floor slab 23 is embedded and fixed. Also, a horizontal joint reinforcing bar 25 that is bound to the vertical portion extending vertically below the rear vertical reinforcing bar 3 and the lower edge side lower reinforcing bar 21 of the lower floor slab 23 by welding or a wire.
The base side of the L-shaped reinforcing bar 26 having
The horizontal joint reinforcing bar 25 in the L-shaped reinforcing bar 26
The base end portions of the parallel short joint reinforcing bars 27 parallel to each other at a higher level are fixed to the vertical reinforcing bars 2 and 3 by a wire or the like and embedded and fixed in the concrete 8. In the case of the PCA-made PC web 1 located in the middle in the direction perpendicular to the bridge axis, as shown in FIGS. 5 and 12, on the side opposite to the direction in which the short joint reinforcing bar 27 in the lower extension 18 extends, A sleeve-shaped screw-type connection fitting for reinforcing bar connection is provided, and a vertical portion of the L-shaped rebar 26 is omitted, and a screw-type connection fitting for sleeve-shaped rebar connection is provided at an end of the horizontal joint reinforcing bar 25. 41 are provided.

As shown in FIG. 6, at one end or both ends of the web 11 in the bridge axis direction, trapezoidal square wave type irregularities 49 which are continuous in the vertical direction are continuously provided. The end face of the unevenness 49 is a plane parallel to the direction perpendicular to the bridge axis. The trapezoidal square wave-shaped projections and depressions 49 are fitted in a male-female relationship with the trapezoidal square wave-shaped projections and depressions 49 of the PCA-made PC web 1 connected in the bridge axis direction. Has become.

When the PCA-made PC web 1 is constructed in a field yard or a factory, if the PCA-made PC web is constructed such that one side of the PCA is substantially flat, the rebar arrangement work is performed. And the concrete placing work can be performed efficiently. In addition, capital box girder 2
The PCA-made PC web 1 on the 8 side is built with the web thickness increased.

Next, referring mainly to FIGS. 7 to 14, the PC web 1 made of PCA according to the first embodiment of the present invention will be used to remove the concrete box girder from the column head box girder 28 of the pier or abutment. The procedure for building the (main girder) 29 in the bridge axis direction and the joining structure between the upper slab (slab) 13 and the lower slab (slab) 23 in that case will be described.

When a concrete bridge is constructed using the PCA-made PC web 1, it can be constructed by various conventionally known methods. For example, a scaffold and a gantry can be erected on the ground. In such a case, a scaffold and a gantry are appropriately erected, and a lower floor slab 23 constituting a concrete box girder 29 is constructed on the gantry so as to project from both sides of the capital box girder 28 in the bridge axis direction. A pair of side PCA PC webs 1 (1A) and a required number (one in the illustrated case) of PCA PCs 1 (1B) for intermediate portions are placed on the lower mold 32 on the mold 32. In a state where the level is adjusted via a spacer (not shown) or the like, they are arranged substantially parallel and vertically at intervals in the direction perpendicular to the bridge axis, and each of the PCA P
An upper formwork 33 for constructing the upper floor slab 13 is installed above the C webs 1A and 1B.

Next, a lower reinforcing bar 35 for the upper floor slab 13 in a direction perpendicular to the bridge axis is placed over the upper surface of the upper bulging portion 12 of each of the PCA-made PC webs 1. The upper reinforcing bar 36 in the direction perpendicular to the bridge axis of the upper floor slab 13 is in contact with the upper joint reinforcing bar 15 provided at the upper end of the vertical reinforcing bars 2 and 3 and is bound by welding or a wire. An upper reinforcing bar 37 and a lower reinforcing bar 38 in the direction of the bridge axis are arranged on the upper reinforcing bar 36 and the lower reinforcing bar 35 in the direction perpendicular to the bridge axis, are bound by welding or a wire, etc., and are disposed in the width direction of the width stopping bar 38a and the bridge axis. Been PC
An inclined reinforcing bar 39 arranged to extend to the lower end of the PC web bulging portion made of A is bound and a reinforcing bar 40 for the upper floor slab is arranged. The joint reinforcing bars (not shown) projecting from the capital box girder 28 and the reinforcing bars extending in the respective bridge axis directions are appropriately connected by joint fittings or the like. Further, a cable insertion duct (not shown) is provided in the upper floor slab so as to extend in the bridge axis direction as appropriate. The concrete 8 for the upper floor slab is cast in the state where the reinforcements are arranged as described above, and the upper side of the concrete box girder 29 of one unit is built.

Next, each of the PCAs adjacent to each other in the direction perpendicular to the bridge axis.
A lower edge upper reinforcing bar 42 in a direction perpendicular to the bridge axis, which is superimposed on the short joint reinforcing bar 27 of the lower overhang portion 18 of the PC web 1 and is bound by welding or a wire, and is screwed to the reinforcing bar connecting bracket 40. L-shaped rebar 2
6 or the joint reinforcing bar 25 whose longitudinal portion is omitted, is bonded by welding or a wire, and the lower edge side lower reinforcing bar 21 in the direction perpendicular to the bridge axis screwed to the connecting fitting 41 is arranged. I have. A lower edge side upper main bar 43 and a lower edge lower main bar 44 in the bridge axis direction are disposed on the lower edge side lower reinforcing bar 21 and the lower edge side upper reinforcing bar 42 in the direction perpendicular to the bridge axis, and are tied together by welding or a number line, and width stop. The reinforcing bars 45 are arranged and bound, and the reinforcing bars 45 for the lower slab are arranged. In addition,
A joint reinforcing bar (not shown) projecting from the column box girder 28 and each reinforcing bar extending in each of the bridge axis directions are appropriately connected to each other by a joint fitting or the like. Also, a PC steel rod or a cable insertion duct (not shown) is provided in the lower floor slab so as to extend in the bridge axis direction as appropriate. The concrete 8 for the lower floor slab is poured in the state where the reinforcement
The lower edge of the concrete box girder 29 of the unit is built, and the concrete box girder 29 of one unit is built.
Similarly, a new PCA PC web 1 is arranged in the bridge axis direction, and the trapezoidal angular corrugations 49 of the new PCA PC web 1 and the existing PCA PC web 1 are engaged with each other, and a joint material is appropriately formed. The construction of a new concrete box girder 29 is to be carried out.

After the concrete box girder has hardened and developed a predetermined strength, as shown in FIG. 14, the inner cable (or tensioning PC steel) 46 in the box girder cross section is appropriately formed as shown in FIG.
In addition, the concrete box girder 29 of one or two units is tensioned in the bridge axis direction by the outer cable 47 inside the box girder, and is fixed in a state where a prestress is applied. In this way, each concrete box girder is built so as to extend in the bridge axis direction, and after constructing and building a concrete box girder spanning all spans, a continuous outer cable 47a is arranged,
This is fixed under tension. In the perspective view showing a part of the completed concrete bridge shown in FIG. 14, an outer cable deflection partition 48 is appropriately provided inside the concrete box girder 12 in the bridge axis direction and embedded and arranged in the partition. The outer cable 47 is inserted through the deflecting hole, and is attached to the deflecting hole with mortar, an adhesive, or the like. Reference numeral 52 denotes a median strip, and reference numeral 53 denotes a surface pavement material such as asphalt.

Next, a PCA-made PC web 1 according to a second embodiment of the present invention will be described with reference to FIGS. FIGS. 15 to 20 show a precast prestressed concrete web (hereinafter referred to as PA manufactured by PCA) of a second embodiment of the present invention.
15 is a partially cut-out vertical front view, and FIGS. 16 (a) and (b) and FIG. 17 are cross-sectional plan views of the lower part. FIGS. 16 (a) and 16 (b) show P adjacent to each other in the bridge axis direction.
FIG. 18 shows a cross-sectional form of an arc-shaped waveform of the CA-made PC web 1, and FIG.
FIG. 20 is a partially cutaway side view showing an end portion.

In the case of the second embodiment, the PCA PC
The difference from the first embodiment is that the cross section of the web 1 in the bridge axis direction is a substantially arc-shaped corrugated shape, but the other configuration is the same as that of the first embodiment. Are described, and the same parts are denoted by the same reference numerals and the description thereof will be simplified.

PCA PC web 1 of the second embodiment
As shown in FIG. 15 to FIG. 18, a front reinforcing bar is formed by bending a single reinforcing bar in a U-shape, extending in the vertical direction, and disposed in parallel in the front-rear direction. A plurality of U-shaped vertical reinforcing bars 9 provided with the rear vertical reinforcing bar 2 and the rear vertical reinforcing bar 3 are arranged at intervals in the bridge axis direction, and are arranged in parallel on a substantially arc-shaped locus bent in a wave form. Between the reinforcing bars 3, a large number of front transverse reinforcing bars (hereinafter simply referred to as front bent transverse reinforcing bars) 4, which extend in the bridge axis direction and are bent in a wavy manner at intervals in the vertical direction, and bent in a wavy manner. A large number of rear horizontal reinforcing bars (hereinafter simply referred to as rear bent horizontal reinforcing bars) 5 are arranged and bound by welding or a number line, etc., and are provided above the front vertical reinforcing bars 2 and the rear vertical reinforcing bars 3 in the first embodiment. The width in the direction perpendicular to the bridge axis is wide (almost two Closed loop-shaped hoops 6 which are closed in a rectangular annular shape (wider than the width between the arc-shaped trajectories constituting the wall surface) are arranged in parallel at intervals in the bridge axis direction, and the front vertical reinforcing bars 3 and It is bound to the rear vertical reinforcing bar 3 by welding or a wire. Accordingly, the U-shaped vertical reinforcing bar 9 having the front vertical reinforcing bar 2 and the rear vertical reinforcing bar 3 is changed so that the position of the U-shaped vertical reinforcing bar 6 conforms to the locus of the closed loop-shaped hoop bar 6 in the direction perpendicular to the bridge axis. are doing.

A plurality of upper horizontal reinforcing bars 7 (four in the illustrated example) extending in the bridge axis direction extend in parallel with the bridge axis direction so as to abut on the inner corners of the hoop bars 6. And are bound to the hoop 6 and the rear vertical reinforcing bar 3 or the front vertical reinforcing bar 2 by welding or a wire. Between the front bent horizontal reinforcing bar 4 and the rear bent horizontal reinforcing bar 5, between each of the vertical reinforcing bars 2, 3 adjacent in the bridge axis direction, extending in the vertical direction, and being parallel at intervals in the bridge axis direction. To P
A PC steel material 10 made of a C steel strand is arranged in a state where a pretension is given in advance on a center line which is bent into an arcuate corrugated shape, and the PC steel material 10 is provided together with the rebars.
After the concrete 8 hardens after the concrete 8 hardens, the tension of the PC steel is released, and the concrete 8 is relatively hardened. Web 11
Is given a vertical prestress. The PC
The steel material 10 is arranged in an arc-shaped corrugated crown portion, and is given a prestress in order to increase a shear resistance and a bending resistance.

Since the concrete web 11 is bent in the bridge axis direction with a width in the direction perpendicular to the bridge axis, the upper bulging portion 12 provided at the upper end of the concrete web 11 becomes wide. However, other points are the same as those in the first embodiment. The upper bulging part 1
The operation and effect of the second embodiment are also the same as those of the first embodiment, and thus the description thereof is omitted.

Since the upper bulging portion 12 provided at the upper end of the concrete web 11 is wide, it is ensured that the web 1 having an arc-shaped cross section of the entire length in the bridge axis direction is ensured.
1 can transmit a shear force.

The inside of a haunch portion reinforcing reinforcing bar 24 provided in a lower overhang portion (lower swelling portion) 18 extending at a lower end portion of the concrete web 11 in a bridge axis direction and projecting in a direction perpendicular to the bridge axis. (U-shaped vertical reinforcing bar 9 side), the lower edge side upper reinforcing bar 50 abuts on the lower part of each short joint reinforcing bar 27, is bound by welding or a wire, etc., and a bridge is formed above the L-shaped reinforcing bar 26. The lower edge side reinforcing reinforcing bar 51 extending in the axial direction abuts and is embedded in the lower slab concrete 8 in a state of being bound by welding or a wire.
The upper and lower reinforcing bars 50 and 51 on the lower edge side are arranged parallel to the locus of the web 11 bent in a wave form at intervals and are fixed in the overhanging concrete 8.

The end surface of the web 11 in the bridge axis direction is an end surface parallel to the direction perpendicular to the bridge axis. On one end or both ends of the web 11, trapezoidal square wave type irregularities 49 continuous in the vertical direction are provided. The surface of the trapezoidal square wave type unevenness 49 is provided continuously, and is a surface parallel to the direction perpendicular to the bridge axis. The end of the web 11 in the bridge axis direction is an end face parallel to the bridge axis perpendicular direction even when using a PCA PC web having a different waveform shape or pitch in the bridge axis direction due to an external cable or the like. If the compressive force in the bridge axis direction can be transmitted reliably, and if the phase of the wave pitch at both ends in the bridge axis direction is the same on the transverse plane of the corrugated web, the PCA PC web is connected to the PCA PC web in the bridge axis direction by an external cable. It is preferable that an eccentric moment does not act even when a compressive force is applied. The trapezoidal square wave type irregularities 49 are connected so that they are adjacent to each other in the bridge axis direction.
It is the same as the case of the first embodiment in that the trapezoidal square wave-shaped unevenness 49 of the PC web 1 is fitted in a male and female relationship, and serves as a fitting and locking portion for transmitting shear force in the vertical direction. .

When the PC web 1 made of PCA is to be built at a site yard or a factory, the PC web 1 is used.
Manufactured using a substantially curved mold for forming one curved side of the A-made PC web and a substantially curved mold for molding the other curved side of the PCA-made PC web. And adjust the spacing of these molds,
The web thickness of the PCA PC web can be adjusted to the thickness appropriate for the concrete bridge. By simply adjusting the spacing between the molds, the formwork can be diverted even when the PCA PC webs have different web thicknesses. Since it is possible, the mold can be used efficiently. Further, the PC web 1 made of PCA on the side of the capital box girder 28 can be manufactured by adjusting the interval between the curved molds even when the web thickness is increased and built.

Next, referring mainly to FIGS.
PC made by PCA in the second embodiment of the present invention
Procedure for constructing a concrete box girder (main girder) 29 from the capital box girder 28 in the bridge axis direction using the web 1 and the upper floor slab (slab) 13 and the lower floor slab (slab) in that case The joining structure with the H.23 will be described. Also in this case, since it is the same as the first embodiment, the differences will be mainly described, and the same parts will be denoted by the same reference numerals and the description thereof will be simplified.

The upper and lower slabs of the concrete box girder are constructed using the PC web 1 made of PCA having the arc-shaped waveform of the second embodiment, and the concrete box girder 29 and the total length in the bridge axis direction are constructed. In the case of constructing a concrete bridge, the bridge can be constructed in the same manner as in the above embodiment, and the difference is that the arc-shaped corrugated cross-sectional plane of the PCA PC web 1 shown in FIG. The form and the PCA-made PC web 1 shown in FIG. 16 (b) are arranged alternately in the bridge axis direction in the form of a cross section of an arc-shaped waveform.
Other points are the same as those in the first embodiment. Also, in the arc-shaped waveform plane form, if the starting end side and the end side in the bridge axis direction of the arc-shaped waveform in one PCA PC web are aligned with the peaks or valleys, the cross-sectional plane form of one arc-shaped waveform is obtained. Can be arranged in series while engaging and contacting the ends in the bridge axis direction.

After the concrete box girder has hardened to a predetermined strength, as shown in FIG. 30, the inner cable (or tensioning PC steel material) 46 and the outer girder inside the box girder are appropriately formed in the box girder cross section. With the cable 47, the one or two unit concrete box girder 29 is tensioned in the bridge axis direction and fixed in a state where a prestress is applied, and each concrete box girder is constructed so as to extend in the bridge axis direction. After constructing and constructing a concrete box girder spanning all spans, a continuous outer cable 47 is arranged and fixed in a tensioned state in the same manner as in the first embodiment. In a perspective view showing a part of the completed concrete bridge shown in FIG. 30, a partition 48 for deflecting the outer cable is appropriately provided inside the concrete box girder 12 in the bridge axis direction and embedded and arranged in the partition. The outer cable 47a is inserted into the through hole for the deflecting portion, and is also attached with a mortar, an adhesive, or the like in the same manner as in the first embodiment.

In practicing the present invention, the upper swelling portion and the lower overhanging portion of the PCA PC web may be omitted, and the web may be directly fixed to the lower slab or the upper slab.
Alternatively, the entire box girder of one unit may be manufactured in a factory and arranged in series in the bridge axis direction, or all may be precast PCA PC webs, PCA lower slabs, and PCA upper slabs. What is manufactured separately from the floor slab may be assembled on site. In this case, connecting lateral holes are provided at the upper and lower ends of the PCA PC web at intervals in the bridge axis direction, and a conventionally known connecting means such as a reinforcing bar or a connecting bolt is inserted as appropriate. You may.

The PC of the PC web of the embodiment described above.
Since the steel material is a pretension steel material and a pre-grouted steel material is used, the reliability of construction can be improved.

In practicing the present invention, PCA PC
It is also possible to omit the upper swelling portion and the lower swelling portion of the web, make the whole a bent waveform shape, and project the connection joint and the dowel bar from the respective upper and lower ends. The number of arc-shaped waveforms of the PCA PC web may be one in the bridge axis direction. In the above embodiment, two PCA PC webs on the end side and one PCA PC web are provided in the middle in the direction perpendicular to the bridge axis. However, the PCA PC web in the middle is omitted. It may be.

[0041]

According to the precast prestressed concrete web for a prestressed concrete bridge according to the first aspect of the present invention, almost all of the PC steel material is adhered to concrete, so that integration with concrete is ensured. Since it is not necessary to perform a rust-proofing process as compared with a conventional steel web, maintenance is easy. In addition, since the prestress can be reliably applied, not only the shear strength can be increased, but also the weight of the member can be reduced, so that not only the weight of the upper structure can be reduced, but also the upper structure is supported. The load on the foundation or the lower structure can be reduced, and the live box at a position away from the PCA PC web in the direction perpendicular to the bridge axis, such as the overhanging flange portion of the concrete box girder using the same, can reduce the web load. At the end in the thickness direction, even if a load biased in the vertical direction acts on the PCA-made PC web and a tensile load acts on the PCA-made PC web, a compressive force (prestress) acts on the PCA-made PC web in advance.
It is possible to prevent the tensile force from acting on the concrete, and to reduce the labor required when constructing a concrete bridge. There is an effect that can be improved.

In the case of claim 2 of the present invention, claim 1
In the precast prestressed concrete web according to the outer surface of the middle part in the vertical direction of the precast prestressed concrete web is a cross section,
Since it is a curved outer surface such as a waveform in the bridge axis direction, expansion and contraction deformation performance can be given in the bridge axis direction, so when introducing prestress in the bridge axis direction, improvement of prestress introduction efficiency In addition, since it is bent in the direction perpendicular to the bridge axis, it is possible to obtain effects such as a high shear buckling strength.

In the case of the third aspect of the present invention, an upper swelling portion and a lower swelling portion are provided at upper and lower ends of the precast prestressed concrete web in the vertical direction, respectively. A joint member made of an upper joint reinforcing bar or the like protruding in the lateral direction in the direction perpendicular to the bridge axis is provided, and a joint member made of a lower joint reinforcing bar or the like protruding in the lateral direction in the direction perpendicular to the bridge axis from the lower bulging portion is provided. Because it is provided, the upper swelling part can have high shear resistance in the vertical direction and the direction perpendicular to the bridge axis, and the upper swelling part can easily cast in place upper slab (floor slab) or precast concrete. Integrated with the upper floor slab, or slab cast down in place (floor slab)
Alternatively, effects such as easy integration with the precast concrete upper slab can be obtained.

In the case of the fourth aspect of the present invention, the precast prestressed concrete web is provided with a large number of trapezoidal angular corrugations at the end in the bridge axis direction so as to extend in the vertical direction. Precast prestressed concrete webs adjacent to each other in the axial direction can be reliably engaged with each other to increase the shear resistance in the vertical direction.

According to the fifth aspect of the present invention, since the web extending in the longitudinal direction of the bridge is formed of a precast prestressed concrete web bent in an arc-like waveform, the rigidity in the axial direction is lower than that of the conventional straight web. The pre-stress in the bridge axis direction should be introduced within the permissible range of one or more units of telescopic deformation in the bridge axis direction or within the permissible range of telescopic deformation of the entire length, because of the property of allowing less elastic deformation in the bridge axis direction. In the case of curved shapes such as arc-shaped waveforms, the bending stiffness is higher and the shear buckling resistance is higher than that of flat plates of the same thickness. For example, even if the concrete web thickness is about 30% of the concrete web thickness, the same shear buckling strength can be achieved, so that the construction cost can be reduced. . In addition, maintenance costs are low, and maintenance costs can be reduced.

In the case of the sixth aspect of the present invention, substantially the entire length of the PC steel material arranged so as to extend in the vertical direction is directly attached to the concrete, and the PC steel material into which the pretension is introduced is applied to the reinforced concrete web. Precast prestressed concrete webs with prestressing applied vertically are arranged on both sides in the direction perpendicular to the bridge axis, and a large number of them are arranged in series in the bridge axis direction to ensure integration with concrete. Since a precast prestressed concrete web which does not need to be subjected to a rust-proof treatment as compared with a conventional steel web is used, a concrete bridge which can be easily maintained and managed can be provided. In addition, the use of a relatively lightweight precast prestressed concrete web with high rigidity to which prestress is reliably applied can reduce the weight of the upper structure and reduce the burden on the foundation or lower structure supporting the upper structure. There are effects such as that a concrete bridge with reduced workability can be obtained.

In the case of the seventh aspect of the present invention, a cast-in-place upper reinforced concrete floor slab and a lower reinforced concrete floor slab are provided on the upper and lower portions of the precast prestressed concrete web and are integrally connected. Compared to a bridge using a conventional steel web, concrete is connected to each other, so integration can be easily performed, and the entire main girder can be made of concrete and a beautiful concrete bridge can be made. Has the effect.

In the case of the eighth aspect of the present invention, the outer side surface of the precast prestressed concrete web at the middle in the vertical direction is a cross-sectional surface and is a curved outer surface such as a waveform in the bridge axis direction. In the direction of bridge axis, pre-stress can be introduced to improve the efficiency of pre-stress introduction, and because of bending in the direction perpendicular to the bridge axis, high shear buckling can be achieved. It can be a prestressed concrete bridge equipped with a precast prestressed concrete web that has strength, and the landscape is good. The elastic deformation performance is higher than that of the web, so that it can be expanded and contracted in the bridge axis direction and buffered.

[Brief description of the drawings]

FIG. 1 is a partially longitudinal front view showing a precast prestressed concrete web according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional plan view showing a state cut in the vicinity of an upper bulging portion in FIG.

FIG. 3 is a cross-sectional plan view showing a state cut in the vicinity of a lower end portion of FIG. 1;

FIG. 4 is a partially cut-away longitudinal side view of FIG. 1;

FIG. 5 is a partially cutaway side view showing an end of a PCA-made PC web at an intermediate portion in a direction perpendicular to the bridge axis.

FIG. 6 is a partially cutaway side view showing an end of the precast prestressed concrete web shown in FIG. 1;

FIG. 7 is a side view of the bridge showing a state where a concrete bridge is erected using the PCA PC web of the form shown in FIG. 1;

FIG. 8 is a partial cross-sectional plan view of the bridge showing a state where a concrete bridge is erected using the PCA-made PC web of the form shown in FIG. 1;

FIG. 9 is a front view of the vicinity of the end in FIG. 7;

FIG. 10 is a partially longitudinal front view of the vicinity of the center of the span.

FIG. 11 shows a state in which an upper PCL slab for connection and a lower slab PCL for connection are constructed on the upper and lower parts of the PCA PC web disposed at the end, and at the upper and lower portions of the PCA PC web disposed at the center. It is a vertical front view.

FIG. 12 is a partially cut-away longitudinal front view showing the end side of FIG. 11;

FIG. 13 is a partially cutaway vertical sectional front view showing a central portion side of FIG. 11;

FIG. 14 is a partially longitudinal front view showing a state in which an outer cable is arranged in a box girder cross section.

FIG. 15 is a partially longitudinal front view showing a precast prestressed concrete web according to a second embodiment of the present invention.

16 (a) and (b) are cross-sectional plan views showing the cross-sectional plan form of the arc-shaped corrugated web when cut in the vicinity of the upper bulging portion in FIG.

FIG. 17 is a cross-sectional plan view showing a state cut in the vicinity of a lower end portion of FIG. 15;

FIG. 18 is a partially cutaway longitudinal side view of FIG.

FIG. 19 is a partially cutaway side view showing an end of a PCA-made PC web at an intermediate portion in a direction perpendicular to the bridge axis in the second embodiment.

FIG. 20 is a partially cutaway side view showing an end of the precast prestressed concrete web shown in FIG. 14;

21 is a side view of the bridge showing a state where a concrete bridge is erected using the PCA-made PC web of the form shown in FIG.

FIG. 22 is a partial cross-sectional plan view of a bridge showing a state where a concrete bridge is erected using the PC web made of PCA in the form shown in FIG. 14;

FIG. 23 is a schematic arrow view taken along the line AA of FIG. 21;

24 is a schematic cross-sectional view taken along the line BB of FIG. 21 near the center of the span.

25 is a schematic sectional view taken along the line CC of FIG. 21.

26 is a schematic sectional view taken along line DD of FIG. 21.

FIG. 27 shows a state in which an upper PCL slab for connection and a lower slab for connection are laid on the upper and lower parts of the PCA PC web disposed at the end, and the PCA PC web disposed at the center. It is a vertical front view.

FIG. 28 is a partially cut-away longitudinal front view showing the end portion side of FIG. 27;

FIG. 29 is a front view, partially cut away, showing a central portion side of FIG. 27;

FIG. 30 is a partially longitudinal front view showing a state where an outer cable is arranged in a box girder cross section.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 Precast prestressed concrete web 2 Front vertical reinforcing bar 3 Rear vertical reinforcing bar 4 Front horizontal reinforcing bar 5 Rear horizontal reinforcing bar 6 Hoop reinforcing bar 7 Upper horizontal reinforcing bar 8 Web or floor slab concrete 9 U-shaped vertical reinforcing bar 10 PC steel 11 Concrete Web 12 Upper bulging part 13 Upper floor slab 14 Upper main reinforcing bar 15 Upper joint reinforcing bar 16 Upper intermediate reinforcing bar 17 Reinforcing bar fitting 18 Lower overhanging portion (lower bulging portion) 19 Upper vertical portion 20 Inclined portion 21 Lower reinforcing bar 22 Lower horizontal portion 23 Lower Floor Slab (or Lower Floor Slab) 24 Haunch Reinforcing Bar 25 Joint Reinforcing Bar 26 L-shaped Reinforcing Bar 27 Short Joint Reinforcing Bar 28 Column Head Box Girder 29 Concrete Box Girder 32 Lower Form 33 Upper Form 35 Bridge Axle Right Angle Lower reinforcing bar in the direction 36 Upper reinforcing bar in the direction perpendicular to the bridge axis 37 Upper reinforcing bar in the direction of the bridge axis 38 Bridge axis direction Lower reinforcing bar 39 inclined reinforcing bar 40 connecting fitting 41 connecting fitting 42 lower edge side upper reinforcing bar 43 lower edge side upper main reinforcing bar 44 lower edge side lower main reinforcing bar 45 lower slab reinforcing bar 46 inner cable (or PC steel material for tension) 47 outer cable 48 outer cable deflection Partition walls 49 Trapezoidal square corrugations 50 Lower edge side upper reinforcing bar 51 Lower edge lower reinforcing bar 52 Median strip 53 Surface pavement material

Claims (8)

[Claims] In a concrete web for a bridge main girder, a large number of PC steel materials are arranged so as to extend in a vertical direction and are spaced at intervals in a bridge axis direction. A precast prestressed concrete for a concrete bridge, wherein a prestressed vertical direction is given to a reinforced concrete web by the PC steel material which is embedded and fixed in concrete in a state of being directly adhered, and which is directly adhered over almost the entire length. Web. 2. An outer surface of a middle part in a vertical direction of the precast prestressed concrete web has a cross section,
The precast prestressed concrete web according to claim 1, wherein the web is a curved outer surface having a waveform or the like in a bridge axis direction. 3. An upper swelling portion and a lower swelling portion are provided at upper and lower ends of the precast prestressed concrete web in a vertical direction, respectively, and are provided in a lateral direction perpendicular to a bridge axis from the upper swelling portion. A joint member consisting of a protruding upper joint reinforcing bar etc. is provided,
The precast prestressed concrete web according to claim 1, wherein a joint member made of a lower joint reinforcing bar or the like protruding from the lower bulging portion in a lateral direction perpendicular to the bridge axis is provided. 4. The precast prestressed concrete web is provided with a large number of trapezoidal angular corrugations at the end in the bridge axis direction so as to extend vertically. 3. The precast prestressed concrete web according to any one of 3. 5. A prestressed concrete bridge having a precast prestressed concrete web, wherein the web extending in the longitudinal direction of the bridge is formed of a precast prestressed concrete web bent in an arc-shaped waveform or the like. 6. A P disposed so as to extend in a vertical direction.
Almost the entire length of the C steel material is directly attached to the concrete, and a precast prestressed concrete web in which the reinforced concrete web is prestressed in the vertical direction by the pre-tensioned PC steel material is provided on both sides in the direction perpendicular to the bridge axis. A prestressed concrete bridge having a precast prestressed concrete web, wherein the prestressed concrete webs are arranged in series in the bridge axis direction. 7. The cast-in-place prestressed concrete web is provided with a cast-in-place upper reinforced concrete floor slab and a lower reinforced concrete floor slab on the upper and lower sides thereof, and are integrally connected. A prestressed concrete bridge comprising the precast prestressed concrete web according to the above. 8. An outer side surface of the precast prestressed concrete web at an intermediate portion in a vertical direction has a cross section,
The prestressed concrete bridge having a precast prestressed concrete web according to any one of claims 5, 6 and 7, wherein the outer surface is a curved outer surface having a waveform or the like in the bridge axis direction.