JP6541520B2 - Renewed construction method of existing road and rebuilt road - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a method of renewing an existing road and a renewed road.

  Deterioration of expressways constructed in the 1940s and 1950s has become apparent, and it is predicted that construction work to replace the floor slabs of roads that are cracked and cracked will increase in the next few years or so It is done.

  In the replacement work of the floor version, traffic regulation such as traffic closure is forced not a little, and the social impact of traffic regulation occurring in many parts of the country is immeasurable, and the contractor of the construction allowed traffic regulation period such as traffic closure It is easily assumed that the desire to shorten as much as possible is strong.

  As a representative example of the structure of existing roads such as expressways, reinforced concrete floor slabs are installed on two or more steel main girders, and the whole is roughly configured. Here, a slip stopper such as a stud dowel is generally attached to the upper surface of the main girder, and a reinforced concrete floor slab is constructed in a state where the slip stopper is embedded, and integration of the main girder and the floor slab is achieved There is. More specifically, after installing two or more main girders, rebars for floor slabs are arranged so as to incorporate slip stoppers, concrete is cast at the site, and reinforced concrete floor slabs are constructed. It is.

  Conventionally, as a general method of updating existing roads, the concrete on the main girder is rolled up to expose the slip stopper protruding upward from the floor slab, the upper side of the main girder including the slip stopper is cleaned, and a new slip stopper is Install a new floor block (precast block) with a hole on the lower surface, into which the slip stopper is inserted, and install it on the main girder, repeating this in the longitudinal direction of the main girder for an existing road with a predetermined extension There is a way to update. In this conventional general renewal method, it takes a lot of time to work on the floor slab, which has led to the extension of the construction period required for renewal construction. As described above, in the renewal construction method in which the construction period is prolonged, in the renewal construction which will increase in the future as described above, the construction in which the construction period is shortened as much as possible can not be realized.

  On the other hand, there is a method of cutting the upper flange of the main girder and removing the floor plate and the upper flange together as another renewal construction method. In this construction method, the upper flange of the main girder is welded or bolted at the time of renewal construction. It is necessary to connect by etc. and perform restoration of the main girder, and it takes time for this restoration and construction, and even if traffic regulation can be alleviated, it will also lead to prolongation of the construction period required for renewal construction.

  Here, Patent Document 1 discloses a method of taking the reaction force of the floor slab disassembling apparatus with the lower flange of the main girder and disassembling the floor slab while supporting the floor slab with the floor slab disassembling apparatus. It is not a technology that can suppress the above-mentioned problem, that is, prolongation of the construction period required for renewal construction.

Japanese Patent Application Publication No. 2007-100415

  The present invention has been made in view of the above problems, and provides an existing road renewal construction method capable of shortening the construction period required for renewal construction of the existing road, and a road renewed and constructed by this renewal construction method. The purpose is to

  In order to achieve the above object, the method of updating an existing road according to the present invention is a method of updating an existing road in which reinforced concrete floor slabs are installed on two or more steel main girders. Among them, the first step of leaving only the part on the main girder and removing the other part, a new floor slab block provided with two or more recesses on the lower surface, each recess on the two or more main girder And installing the floor slab block in the extending direction of the road.

  According to the method of the present invention, the existing road is rebuilt without leaving the main girder and removing the reinforced concrete floor slab above the main girder without removing only the portion on the main girder of the floor slab, and so on. It is a construction method characterized by removing the floor plate of

  Since the floor plate on the main girder is not removed, the floor plate is removed by exposing the slip stopper embedded in the floor plate from the upper surface of the main girder, and when cleaning the upper surface of the main girder It is possible to eliminate a large amount of rolling time that is required, and it is possible to significantly reduce the construction time as compared with the conventional renewal construction method.

  In the renewal construction method of the present invention, in two or more main girders, after removing the other decks while leaving only the portion on the main girders of the deck, the precast floor slab block is bridged to each of the main girders To install. For example, in the case of two main girders, a floor slab block is bridged over two main girders, and in the case of five main girders, a floor plank block is bridged over five main girders. Under the present circumstances, the recessed part is provided in two places of the lower surface of a floor slab block in the former form, and the concave part is provided in five places of the lower surface of a floor slab block in the latter form.

  Here, the floor slab block is provided with a recess on the lower surface thereof into which the portion on each main girder fits, and while the portion on each main girder is fitted into the corresponding recess respectively, the floor slab block to two or more main girder Installation will take place.

  As described above, since the floor slab block is installed while inserting the portions on the respective main girders into the corresponding recesses for two or more main girders, there is a risk that the floor slab blocks will be displaced to the side of the main girders. Absent.

  In the second step, by repeatedly performing the installation of the floor slab in the extending direction of the road, a new road composed of a number of floor slabs is constructed, and the renewal construction of the existing road is completed.

  As described above, in addition to the fact that the floor slab block is not displaced to the side of the main girder by the portion on the main girder being fitted into the recess, a number of floor slab blocks are installed in the extending direction of the road As a result, there is no fear that the floor block will shift in the road extension direction.

  Further, in a preferred embodiment of the method for updating an existing road according to the present invention, a slip stopper is attached to the upper surface of the main girder, and a floor slab is embedded in the slip stopper to constitute an existing road. The method in which the portion on the main girder left behind in the step is only the portion of the reinforced concrete on the main girder side on the main girder side below the neutral axis in which the slip stopper is embedded can be mentioned.

  Of the portion on the main girder of the existing floor slab, the portion above the neutral axis is a tensile area (area of negative bending moment) due to bending moment, and a crack is generated in this area.

  In the area below the neutral axis, there is embedded a slip stopper that connects the main girder and the floor slab, and since this area becomes a compression area even in the part on the main girder, there is no occurrence of cracks, and soundness Area. Therefore, in the renewal construction method of the present invention, although the portion on the main girder is left, the portion on the main girder above the neutral axis including the crack is removed, and the sound portion below the neutral axis is removed. Is adopted as "the part on the main girder" in the present specification and is left behind.

  By integrating the area with the floor slab block while leaving only the sound area among the parts on the main girder in this way, one of the components of the connection structure is the part on the main girder made of old reinforced concrete. Even if there is, high connection strength can be expected.

  Further, in a preferred embodiment of the existing road renewal construction method according to the present invention, in the second step, after filling the filler on the portion on the main girder, the recess of the floor slab block is placed on the main girder. It fits on the part.

  By connecting the portion on the main girder to the floor slab block through the filler, the connection interface between the portion on the existing main girder and the new floor slab block has a predetermined shear adhesion strength. Composite beams can be formed with the effective height of the entire deck block. More specifically, since the shear adhesion strength has a strength equal to or higher than the horizontal shear force generated at the connection interface, the portion on the main girder and the floor slab block exhibit the same behavior (the integrated beam described above) Formation of the Therefore, the composite beam described above can be formed, for example, by applying a filler having a shear adhesion strength similar to the horizontal shear strength possessed by the slip stopper on the main girder.

  Here, as the filler to be applied, cement-based fillers such as ordinary mortar, epoxy-based fillers such as epoxy resin and epoxy resin mortar, acrylic-based fillers such as acrylic resin and acrylic resin mortar, polymer-based fillers, etc. Can be mentioned.

  Further, in a preferred embodiment of the method for renovating an existing road according to the present invention, in carrying out the second step, at the upper surface of the newly installed floor slab block, two or more recesses extending in the longitudinal direction of the floor slab block The reinforcement of the length which straddles is attached.

  Since the floor slab block is provided with a plurality of recesses on its lower surface, when the floor slab block is lifted by a crane or the like at the time of installation of the floor slab block, the location having the recess becomes a structural weak portion, and the floor slab block However, there is a possibility that a crack originating from the periphery of the recess of the floor slab block may occur.

  Therefore, in the renewal construction method of the present embodiment, on the upper surface of the new floor slab block, the floor slab block extends in the longitudinal direction (direction orthogonal to the extending direction of the road) and extends over two or more recesses. Reinforcement is attached.

  This reinforcing material can be formed of an H-type steel, an I-type steel, a rod-like concrete block, or the like having a predetermined rigidity.

  In addition, the present invention extends to a rebuilt road, which includes two or more steel main girders, and a reinforced concrete part which is on the main girder and left unrenewed, It consists of a new floor slab block that has two or more recesses on the lower surface, and the recess is installed by fitting it in a part made of reinforced concrete, and a plurality of the above-mentioned floor slab blocks are juxtaposed in the road extension direction is there.

  The renewed construction road of the present invention is constructed by the renewal construction method of the existing road of the present invention described above.

  By installing a reinforced concrete part without being renewed on the main girder, inserting the recess on the lower surface of the floor slab into it and integrating the two into one, construction of a road rebuilt in a short construction period Can.

  In addition, also on this renewed construction road, a slip stopper is attached to the upper surface of the main girder, and the remaining reinforced concrete part is embedded in the shear resist of the reinforced concrete on the main girder before the renewal. It is preferable that it is a portion on the main girder side below the vertical axis.

  Since the part on the main girder side below the neutral axis is a sound part free of cracks, high connection strength can be expected with respect to the connection between old and new reinforced concrete.

  Furthermore, it is preferable that a filler be interposed between the reinforced concrete part and the recess of the floor block.

  By connecting the reinforced concrete section on the main girder with the floor slab block through the filler, the connection interface between the existing reinforced concrete section and the new floor slab block has a predetermined shear adhesion strength, It is possible to form a composite beam with the effective height of the girder and the whole floor block, and to reduce the vertical displacement due to the live load acting as much as possible.

  As can be understood from the above description, according to the method of reworking an existing road of the present invention and the rebuilt road, when removing a reinforced concrete floor slab on the main girder, the main girder in the floor slab is used. Leave only the upper part without removing it, remove the other floor slabs, and construct a rebuilt road in an attempt to unify both while fitting the recess on the lower face of the floor slab block to the part on the main girder As a result, it is possible to dramatically shorten the construction period required for renewal construction.

It is a schematic diagram explaining the 1st step of the update construction method of the existing road of this invention. It is a schematic diagram explaining the 1st step following FIG. It is a figure explaining the ground which sets the portion on the main girder left behind. It is a schematic diagram explaining the 2nd step of the renewal construction method of the existing road. It is a schematic diagram showing a renewed road. It is the figure which showed the three-dimensional model used in the analysis which models the interface state between the part on the left main girder and the floor slab block with a plurality of patterns, and calculates the vertical displacement at the time of live load loading in each model. . It is a figure explaining a plurality of interface pattern models about the interface state between the part on the main girder left behind, and a floor slab block. It is a figure showing the analysis result about the maximum displacement of the floor slab between the main girder at the time of live load loading in each interface pattern model. It is the figure which compared the largest displacement in each interface pattern model.

  Hereinafter, with reference to the drawings, embodiments of the method for updating an existing road of the present invention and a road on which the method for updating is constructed will be described. In addition, although the example of illustration has shown the existing road which consists of two main girders, and the rebuilt road, it is needless to say that the existing road provided with three or more main girders may be the object of renewal construction. It is.

(Renewal construction method of existing road and embodiment of road which was renewed construction)
1 and 2 are schematic diagrams illustrating the first step of the method of updating an existing road according to the present invention, and FIG. 3 is a diagram illustrating the basis for setting the remaining portion on the main girder. These are schematic diagrams explaining the second step. Moreover, FIG. 5 is a schematic diagram which showed the road by which renewal construction was carried out.

  The existing road 10 shown in FIG. 1 is roughly composed of two main girder 1 extending in the extending direction L of the road and an existing reinforced concrete floor slab 2 integrally constructed to each main girder 1 . In addition, the existing road 10 shown in FIG. 1 takes out and is showing the part of the whole road extended in the extension direction.

  The floor plate between the main girder 1 is damaged particularly by a large number of cracks, depressions and the like due to bending moment or the like caused by the active load repeatedly received during the service period.

  When the damaged existing floor slab 2 is to be rebuilt, the reinforced concrete part of the existing floor slab 2 is left on the main girder, and the other part is removed, as shown in FIG. In this state, only the part 4 on the main girder is left (first step).

  Specifically, the worker cuts the existing floor slab 2 obliquely in the vertical or horizontal direction so as to leave only the part 4 on the main girder with a cutting machine such as a chain saw, and removes the cut existing floor slab 2 As a result, the state of FIG. 2 is formed.

  Here, a large number of slip stoppers 3 are attached to the upper surface of the main girder 1, and in the existing road 10, reinforcing bars are arranged so as to surround the slip stoppers 3, and concrete is cast on the spot The existing floor slab 2 made of concrete is constructed so as to embed the slip stopper 3.

  As shown in FIG. 2, in the portion 4 on the main girder formed in the first step, the slip stopper 3 is embedded.

  That is, in the conventional renewal construction method, a general method is to install the precast floor block block on the main girder after sweeping the portion on the main girder until the slip stopper is exposed and cleaning the upper side of the main girder. However, this method required a great deal of time for this anti-slip effect.

  In the renewal construction method to illustrate, in the first step, the existing floor plate in a state in which the slip stopper 3 is embedded inside the portion 4 on the main girder made of reinforced concrete, without protruding until the slip stopper 3 is exposed. Finish the removal of 2. As a result, it is possible to eliminate the great amount of time required for the slippage prevention in the conventional renewable construction method.

  Here, with reference to FIG. 3, the range of the portion 4 on the main digit will be described, that is, a method of setting the range of the portion 4 on the main digit will be described.

  When live load is received, a negative bending moment (−M) is generated above the main girder 1 and a positive bending moment (+ M) is generated between the main girder 1 on the existing road 10. Among them, in the portion 4 on the main girder, the upper side of the neutral axis in the cross section is a tensile area and the lower side is a compression area.

  In the tensioned area, the concrete literally has a crack due to the effect of the tension acting on the concrete, and therefore this tensioned area is an unhealthy area.

  On the other hand, the compressed area is said to be a sound area because no cracks occur in the concrete. Therefore, the area below the neutral axis, which is the sound area, and the area surrounding the shift stopper 3 is defined as the portion 4 on the main girder connected to the floor slab block 6, and is used as the remaining area .

  As shown in FIG. 4, an adhesive filler 5 is applied to the entire surface of the portion 4 on the main girder. Here, as the filler 5, cement-based filler such as ordinary mortar, non-shrink mortar, fiber-containing mortar, epoxy resin, epoxy resin mortar, epoxy-based filler such as epoxy resin grout, acrylic resin, acrylic resin mortar, Acrylic based fillers such as acrylic resin grout, polymer based fillers such as rubber latex mortar, etc. can be applied.

  After the adhesive filler 5 is applied to the entire surface of the portion 4 on the main girder, the floor block 6 made of precast and provided with a recess 6a on the lower surface is suspended by a wire 8 suspended by a crane (not shown) The floor block 6 is placed over the two main girders 1 so that each recess 6a is fitted into the corresponding part 4 on the main girder.

  Here, since the floor slab block 6 has the two recessed portions 6a on the lower surface, the strength in the vicinity of the recessed portion 6a is weak, and the recessed portion 6a which is a structural weak portion when directly suspended by the wire 8. It is feared that cracks may occur around the area.

  Therefore, a reinforcing material 7 having a length extending in the longitudinal direction and straddling the two concave portions 6a is attached in advance to the upper surface of the floor block 6, and the wire 8 is attached to the fastener 7a attached to the reinforcing material 7. , And lift the floor block 6 up.

  In addition, as the reinforcing material 7, steel materials, such as H type steel, I type steel, C type steel, a square steel pipe, a long concrete block, etc. are applicable.

  By repeating the installation of the floor slab block 6 shown in FIG. 4 in the extending direction of the road, as shown in FIG. 5, a large number of floor slab blocks 6 in the extending direction of the road are placed on the two main girder 1. The renewal construction road 20 which is installed is constructed, renewal construction of the existing road is completed (the 2nd step).

  In addition, by connecting the portion 4 on the main girder with the floor slab block 6 via the filler 5, the connection interface between the portion 4 on the existing main girder and the new floor slab block 6 has a predetermined shear adhesion strength. As a result, it is possible to form a composite beam having the effective height of the main girder 1 and the entire floor slab block 6 at this connection point.

  More specifically, since the shear adhesion strength is equal to or higher than the horizontal shear force generated at the connection interface, the portion 4 on the main girder and the floor block 6 exhibit the same behavior (the above-mentioned integration (described above) Formation of composite beams).

  Therefore, it becomes possible to form the above-mentioned synthetic beam by applying filler 5 provided with the same shear adhesion strength as horizontal shear strength which slip stopper 3 on main girder 1 has, for example.

  Also, as shown in the illustrated example, the cross-sectional shape of the portion 4 on the main girder should be trapezoidal with the upper base short with respect to the lower base, and the recess 6a of the floor block 6 should be a shape complementary thereto. Thus, the recess 6a can be easily fitted into the portion 4 on the main girder.

(Modeling the interface state between the left main girder part and the floor slab block with multiple patterns, and determining the vertical displacement during live load loading in each model and its results)
The inventors of the present invention modeled the interface state between the remaining portion on the main girder and the floor slab block with a plurality of patterns, and performed an analysis to obtain the vertical displacement at the time of live load loading in each model. Here, FIG. 6 is a view showing a three-dimensional model used in analysis, and FIG. 7 is a view explaining a plurality of interface pattern models.

  In this analysis, the three span continuous non-synthetic girder bridge designed by the road bridge specification in February 1959 is analyzed, and the loading load is the vehicle load (L load) specified by the road bridge specification. did. Further, as shown in FIG. 6, in the computer, RC floor slabs were modeled by solid elements, the main girder and vertical stiffeners were modeled by plate elements, and the anti-tilting structure was modeled by rod elements. Furthermore, as shown in FIG. 7, the interface state between the portion on the main girder connected via the filler and the floor slab block was of three types: a completely rigid model, a tensile neglect model, and an interfacial peeling model. Then, as condition settings for forming each interface model, each spring constant in the x direction, y direction and z direction is appropriately set, and if necessary, the spring constant in a certain direction is infinite (∞), or Settings such as setting the spring constant in the tension direction to zero were performed.

Physical properties of filler: Case of the conventional example at the time of E _G = 2.0 × 10 ³ N / mm ² , the case of the interface state being a completely rigid model, the case of the interface state being a tension neglect model, and the interface state being an interface The analysis was performed in four cases of the exfoliation model case. The case of the conventional example is a model of an existing road on which a floor slab is constructed with cast-in-place concrete in such a manner as to incorporate slip stoppers on the main girder. Here, FIG. 8 is a diagram showing an analysis result on the maximum displacement of the floor slab between the main girder during live load loading in each interface pattern model, and FIG. 9 is a diagram comparing the maximum displacement in each interface pattern model. is there.

  According to FIG. 8, while the maximum vertical displacement between the main girder of the conventional example, the completely rigid model and the tension neglect model is almost the same, the maximum vertical displacement of the interface peeling model is increased by about 30 to 30%. It has become.

FIG. 9 shows three types of analysis results normalized with this reference value based on the maximum vertical displacement of the conventional example. Furthermore, physical properties of filler: E _G is 2.0 × besides ^{10 3 N / mm 2, 2.0} × 10 1 N / mm 2 ^{cases, 2.0 × 10 2 N / mm} 2 of the case, and 2.0 × 10 ⁴ Analysis is also performed in the case of N / mm ^{2, and in the same way as in} the case of E _G of 2.0 × 10 ³ N / mm ² , the other three types of analysis results are normalized with the maximum vertical displacement of the conventional example as a reference value. ing.

  From FIG. 9, regardless of the physical property value of the filler, it can be seen that the maximum displacement is increased by about 80% in the case of the interfacial separation model in the interfacial state.

  From this analysis result, in the interface state between the portion on the main girder and the floor slab block, interface separation occurs and integration of the main girder and floor slab block can not be achieved in this region, which is attributed to this. It can be seen that the vertical displacement is increased by forming a composite beam and forming a so-called overlapping beam.

  Therefore, it is understood that it is desirable for the applied filler to have a shear adhesion strength such that interfacial peeling does not occur at the connection interface between the portion on the main girder and the new floor slab block.

  As mentioned above, although the embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and there are design changes and the like within the scope of the present invention. Also, they are included in the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Main girder, 2 ... Existing floor version, 3 ... Slack stop, 4 ... Part (The reinforced concrete part) on the main girder, 5 ... Filler, 6 ... floor block, 6a .. 8 ... wire, 10 ... existing road, 20 ... updated construction road

Claims (5)

A method of updating an existing road where reinforced concrete floor slabs are installed on two or more steel main girders,
The first step of leaving only the part on the main girder and removing the other parts of the floor slab,
A new floor slab block having two or more recesses on the lower surface is installed in such a way that each recess fits in the portion on the two or more main girders, and this floor slab block is repeated in the road extension direction Ri Do from the second step,
A slip stopper is attached to the upper surface of the main girder, and a floor plate is embedded in the slip stopper to constitute an existing road,
Renewal construction of the existing road where the part on the main girder left behind in the first step is only the part on the main girder side below the neutral axis which embeds the slip stopper among the reinforced concrete on the main girder Method. In a second step, fitting the recess of the slab blocks after filling the filling material on the portion on the main beam to the portion of the main digits, existing update method of constructing roads according to claim 1. In implementing the second step, the upper surface of the slab blocks in the new, permanently installing longitudinally extending stiffener length spanning two or more recesses of the floor plate blocks, to claim 1 or 2 Renewal construction method of the existing road of statement. With two or more steel main girders,
A reinforced concrete part that was left on the main girder without being updated,
A new floor slab block that has two or more recesses on the lower surface, and the recesses fit into a reinforced concrete part,
A plurality of said slab blocks are parallel in the extending direction of the road, the update construction road.
A slip stopper is attached to the upper surface of the main girder,
A rebuilt road on which the left reinforced concrete part is the part of the reinforced concrete on the main girder before updating, which is the part on the main girder side below the neutral axis on which the slip stopper is embedded. The renewed construction road according to claim 4 , wherein a filler is interposed between the reinforced concrete part and the recess of the floor block.

Images