KR100383314B1 - Upper Structure of PC Beam Bridge and Method of construction it - Google Patents

Abstract

The present invention relates to a PC beam and a bridge superstructure and a method for forming the structure, the structure of which is usually a mold formed with a plurality of PC beams in parallel in the longitudinal direction, an upper plate layer provided on the upper layer of the mold, the length of the mold The non-concrete concrete part, which is installed perpendicular to the longitudinal direction so as to have the same level as the upper plate layer on the upper end of the direction end, is the base for installation of the expansion joint for connection with the alternating part, and can support the entire lower surface of the non-condensed concrete part. And a supporting part installed to traverse the mold in the upper edge space of the end portion of the mold, and the forming method includes forming a PC beam having the upper edge portions of both ends formed into a space, and bridge the plurality of PC beams thus formed. Arranging to form a mold of the plurality of PC beams while crossing the corner portions of the plurality of PC beams And a step of installing a top plate layer such as slab concrete layer and a paving layer on the upper part of the PC beam except the corner part, and installing a non-concrete concrete part having a stretch joint installed on the top part of the support part. Can be.

Description

Upper Structure of PC Beam Bridge and Method of construction it}

The present invention relates to an upper structure of a prestressed concrete (PC) bridge and a repair method thereof, and more particularly, a press to prevent breakage of the non-concrete concrete portion formed for the installation of the expansion joint at the bridge end. The superstructure and the construction method of prestressed concrete (PC) beam bridge.

Bridges can be classified into wood bridges, stone bridges, steel bridges, concrete bridges, and light metal bridges. Among them, in Korea, where the raw materials of steel materials are scarce and expensive, there are abundant raw materials, and there are many applications of concrete, which consumes less energy than steel materials, from the collection of raw materials to the completion of structures. In addition, concrete bridges are widely used in road bridges because they have good structural and linear applicability in consideration of dynamic stability, durability, maintenance cost, and bridge aesthetics.

Such concrete bridges can be broadly classified into reinforced concrete beam bridges and prestressed concrete beam bridges, and more than 90% of domestic bridges are concrete bridges.

Since PC beams were conceived by Fressinet in 1939, the use of PC beams as a bridge material has become commonplace in recent years. Looking at the upper structure of the conventional PC beam bridge schematically, the base structure forming the bridge is made of a plurality of PC beams that can be formed thinner and longer than the general concrete. On top of the PC beam, slab concrete is installed approximately 25 cm thick, and on top of the slab concrete, an 8 cm thick paving ascon is installed (based on PC beam length 30M). Like many other bridges, the PC beam, which is a mold, is installed with alternating alternatives to support the bridges in contact with both alternatives, and the molds are placed on the alternating and alternating alternators. In the case of long bridges, the bridge is placed in the middle and supports the middle of the mold.

However, as shown in the side view of FIG. 1, the PC beam bridge generally has no shrinkage perpendicular to the length of the PC beam 11 in the upper layer of the PC beam 11 at the portion where the PC beam 11 abuts the alternating 21. The concrete part 17 is provided. The non-shrink concrete part 27 is also provided in the upper layer of the shift 21 which opposes the non-shrink concrete part 17 of the upper layer of the PC beam 11. And the expansion-contraction joint which is not shown in figure is provided using the non-contraction concrete parts 17 and 27 provided in the upper layer of the edge part which the PC beam 11 and the alternation 21 oppose. Therefore, the superstructure and the alternating structure of the bridge take the form of being connected by a telescopic joint.

That is, the non-contraction concrete parts 17 and 27 are installed to form the expansion joint. Meanwhile, in the above description, the upper layer of the PC beam 11 or the shift 21 is, for example, the upper plate ascon layer 15 or the paving layer 8 cm and the slab concrete layer formed on the PC beam 11 which is typically molded in the bridge. (13) It becomes the part of 33cm which combined 25cm.

By the way, in the expansion joint part where the superstructure of PC beam bridge and the alternating part 21 are connected, defect generation rate reaches 100% substantially. This is due to the impact when the vehicle passes in the non-concrete concrete portion 17 is installed to install the expansion joint, the crack continues to develop and sag and collapse.

More specifically, the non-concrete concrete portion 17 fixing the metal material of the flexible joint is cold jointed with the slab concrete layer 13 and positioned on the PC beam 11. In the case of the non-contraction concrete portion 17, the concrete strength of the PC beam 11 is only 400 kg / cm 2, while the strength of the concrete has rigidity around 600 kg / cm 2. Therefore, it is difficult to absorb the shock when an impact occurs during the passage of the vehicle due to a part of the step, etc. inherent in the expansion joint portion, and also it is not able to withstand the impact and cracks occur in the non-contraction concrete portion 17. The generated cracks develop as the impact continues, leading to sagging of the non-concrete concrete portion 17 between the PC beam 11 and the PC beam 11 forming the mold, and gradually causing the collapse.

Therefore, the present invention is to solve such a conventional problem, the purpose of the PC beam bridge, a new type of PC beam bridge superstructure that can prevent sagging and collapse of the non-concrete concrete portion and its replacement with the new construction To provide a construction method for.

1 is a view for explaining a problem of a conventional Prestressed Concrete beam bridge (PC);

2 to 5 are diagrams for explaining the construction method of the PC beam bridge according to an embodiment of the present invention.

6 is a diagram for explaining a PC beam bridge according to the present invention;

* Explanation of symbols for the main parts of the drawings

11,11 ': PC beam 13: concrete slab

15,25: Ascon layer 17,27: Non-contraction concrete part

19: support beam 21: shift

23: connection slab layer

PC beam bridge superstructure of the present invention for achieving the above object is a mold which is usually provided with a plurality of PC beams in parallel in the longitudinal direction, an upper plate layer provided on the upper layer of the mold, the upper layer in the longitudinal end of the mold An end portion of the mold to support the entire lower surface of the non-concrete concrete portion, which is installed perpendicular to the longitudinal direction to form the same level as the upper plate layer and is the base of the installation of the expansion joint for alternating connection. It is provided with a support portion which is installed to cross the mold in the tucked portion formed in the upper corner.

The top plate layer is composed of a slab concrete layer and a pavement layer, preferably an ascon layer, coated on the slab concrete layer.

The support portion maintains a level similar to the reinforcement ratio of the slab concrete layer (90% or more level), it is preferable to reinforce the reinforcement more than the reinforcement ratio of the slab concrete layer, the concrete mixing ratio is preferably the mixing ratio of the slab concrete.

PC beam of the present invention for achieving the above object, in the rod-shaped PC beam, characterized in that the upper edge portion of at least one end of both ends is formed to be a jaw.

A typical PC beam is an approximately I-shaped beam and has a constant cross section, but the PC beam according to the present invention has a different cross-sectional shape at at least one end. The jaws are shaped like boxed corners.

PC beam bridge superstructure forming method of the present invention for achieving the above object comprises the steps of forming a PC beam treated with the upper edge of the upper edge, the plurality of PC beams formed so as to form a bridge of the bridge, Installing a supporting part intersecting while filling the corners of the plurality of PC beams, installing a top plate layer such as a slab concrete layer and a paving layer on the upper part of the PC beam except the corner part, and the upper part of the supporting part It can be made by having a step for installing the non-concrete concrete portion is installed in the expansion joint.

When applying the method of forming the PC beam bridge superstructure of the present invention to repair the existing bridge, the non-concrete concrete portion is installed, the existing expansion joint is installed, the upper part of the lower PC beam is formed to be jaw In addition, a support portion may be installed in the jaw portion, and the support portion may be cured, and then a method of installing a non-concrete concrete portion newly installed with a expansion joint may be used.

The support portion may be formed using a method of individually forming one or more support beams and assembling the support beams in a tucked portion formed at the upper edge of the PC beam end for the support portion.

The PC beam used to form the bridge's mold can be formed like a conventional PC beam, and then the upper part of the end can be removed to form a tapped portion (space) for the supporting part, but the strength of the PC beam and the fixing plate are affected. It is desirable to manufacture a PC beam having an upper end portion formed into an empty space in consideration of the strength of the PC beam and the influence on the fixing plate in advance. When forming the support, mechanical strength calculations are to be carried out so that the maximum bending moment can be received above the concrete layer of the bridge slab.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

2 to 5 are cross-sectional views illustrating a method of forming a bridge superstructure of the present invention.

Referring to Figure 2, two PC beams 11 'of the present invention are arranged in parallel to form a mold of a bridge as a simple example. The corners B on both upper ends of the PC beam 11 'have a chin-shaped portion P into an empty space of a box shape. The jaw portion (space) P of the corner B may have a size of about 300 mm in the longitudinal direction of the PC beam 11 'at a height of 330 mm when viewed from the side as shown in FIG. 1 (based on a PC beam length of 30M). ). In the case of a wide mold width of the bridge, an appropriate number of PC beams may be installed in parallel so as to calculate and withstand the moment due to the load of the upper plate and the vehicle.

Referring to FIG. 3, a supporting portion is installed perpendicular to the PC beam 11 'at the tucked portion P of both edges of the PC beam 11' arranged in parallel. The supporting beams 19 are formed separately, and the supporting beams 19 are arranged to cross the mold while filling the tapped portion P of the corners as beams, and then the supporting beams 19 and the PC beams 11. ') May be combined using a binder. As the binding material, an attachment material such as an attachment auxiliary made of mortar or metal may be used. However, the method of joining the supporting part with reinforcing bars or the like while forming the slab concrete layer 13 and simultaneously pouring the concrete into one body is practically preferable. Do.

In addition, the supporting portion does not separately form the supporting beam 19, the beam structure formwork is installed in the tucked portion (P) of the corner (B), which is the supporting space, and the reinforcement ratio higher than the slab concrete layer to reinforcement It can also be formed by pouring a compounding concrete having a strength of about 270 kg / cm 2 with a slab concrete mixing ratio. In this case, the curing period of the poured concrete is preferably at least 7 days.

Once formed, it is desirable that the bearing portion is formed to be strong in impact and hardly be damaged, so that only the non-concrete concrete portion needs to be replaced even when repairing the new joint portion of the bridge.

Referring to FIG. 4, an ASCON layer 15 is provided as a slab concrete layer 13 and a pavement layer on an upper layer of the supporting part, that is, an upper layer of the PC beam 11 ′ excluding the non-contraction concrete part space.

Referring to FIG. 5, the slab concrete layer 13 and the ascon layer 15 are not formed, and thus the non-concrete concrete portion 17 is disposed on both upper layers of the PC beam 11 ′, that is, the upper portion of the support portion. Is installed. Although the expansion joint is not shown in the drawings, the non-contraction concrete portion is installed while installing the expansion joint together with the alternate non-contraction concrete portion. Therefore, in most cases, the step of forming the non-concrete concrete portion 17 will be performed while connecting the shift and the superstructure at the final stage in the construction of the bridge.

In the above process, the installation of the support portion of FIG. 3 and the installation of the slab concrete layer and the asphalt concrete layer of FIG. 4 may be performed in reverse order, and the concrete placement of the support portion and the slab concrete layer may be simultaneously performed.

FIG. 6 is a cross-sectional view illustrating a structure in which the PC beam bridge upper layer structure of the present invention formed through the above process is connected to the shift 21. The expansion joints are not shown. It can be seen that the support portion made of the support beam 19 is formed below the non-contraction concrete portion 17.

According to the present invention, since the new bearing portion reduces the shock and load received by the non-concrete concrete portion forming the expansion joint part of the existing PC beam concrete bridge, cracks easily occur in the non-condensed concrete, and the expansion of the non-condensed concrete portion The collapse phenomenon can be suppressed. This significantly reduces the cost of maintenance on existing PC beam concrete bridges.

Claims (8)

delete A mold comprising a plurality of prestressed concret (PC) beams having tucked portions at both upper edges; A support beam installed in the tucked portion to cross the plurality of PC beams; A non-concrete concrete part installed to be mounted on the support beam and serving as an installation base of the expansion joint for connection with the shift; The upper structure of the PC beam bridge, characterized in that it comprises an upper plate layer installed on the upper layer of the mold to achieve the same level as the non-contraction concrete portion. The method of claim 2, The upper plate layer, the PC beam bridge superstructure, characterized in that consisting of a slab concrete layer and an asphalt concrete layer coated on the slab concrete layer. The method of claim 3, wherein The supporting beam is reinforced by the reinforcing bar is 90% or more of the reinforcement ratio of the slab concrete layer, the concrete mixing ratio is the same as the mixing ratio of the slab concrete PC beam bridge superstructure. Arranging a plurality of PC beams formed by processing the upper edges of both ends in a mold; Installing a support to traverse the PC beams while filling the tucked portions of the corners of the plurality of PC beams; Installing an upper plate layer on the upper layer of the PC beam except for the corner at which the support unit is installed; And Comprising the step of forming a non-concrete concrete portion is installed on the upper portion of the expansion joint is constructed. The method of claim 5, Installing the support portion is combined with installing the top plate layer, Individually forming a receiving beam, Arranging the support beam to cross the PC beams while filling the tucked portion of the corner, such as a beam, and Comprising the step of combining the supporting beam and the PC beam using the concrete pouring at the time of slab concrete layer installation of the upper plate layer PC beam bridge superstructure construction method. Removing the non-concrete concrete portion in which the expansion joint of the existing bridge is installed; Removing a portion of the upper edge of the PC beam below the non-concrete concrete portion to form a tucked portion; Installing a support on the jaw portion; And PC beam bridge superstructure construction method comprising the step of installing a non-condensed concrete unit newly installed expansion joint on the upper portion. The method of claim 7, wherein Installing the support portion, Installing a beam structural formwork on the jaw portion; Reinforcing the reinforcement ratio to increase the reinforcement ratio than the slab concrete layer; Pouring compounding concrete with slab concrete mixing ratio; And PC beam bridge superstructure construction method comprising the step of curing the compounded concrete poured for 7 days or more.