JP2008274637A - Construction method for continuous viaduct - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simple technology of hoisting a form with a longitudinal unit length by using a simple temporary girder, of making the form supported on the temporary girder in a communicating manner, and of performing construction by means of a support for bearing a concrete load. <P>SOLUTION: The temporary girder 10 with a suspended movable lifting device 13 is placed on a bracket 20 which is provided with bridge piers 100a, 100b, 100c, ...; a bridge body form 30 with a bridge-axis-direction unit length is conveyed below a span, lifted up by the lifting device 13, supported by the temporary girder 10, and sequentially connected for the assembly of forms 31, 32, ... for one span; an auxiliary support 50 for bearing a concrete load is erected in a bridge-axis-direction intermediate section of them, so that concrete can be placed in the form; prestress is introduced; and a connection to an existing bridge body is established. After that, the auxiliary support 50 is removed; the forms 31, 32, ... are sequentially lowered, and conveyed to the next construction span; and the above operations are repeated. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a construction method for continuous viaduct. More specifically, the present invention relates to a novel technique that can simplify a support work and construct a bridge body when a support work is installed under the viaduct and an on-site prestressed concrete viaduct is constructed.

  Conventionally, in general, the construction of continuous viaducts under the condition that the support works can be assembled on the ground below the viaducts, in many cases, a grounded fixed support work, a framework or a support using a column type support material has been used. When constructing a continuous viaduct spanning multiple diameters, considering the economic efficiency, the support materials for several diameters will be constructed while being diverted. Between each span, the state of the support foundation, such as the shape of the ground and the soil, also changes, and the payment of the support works depends almost entirely on human power.

  For the construction method using fixed support, install the support directly on the ground of the installation site, install the support on the footing of the substructure, or install the support by fixing the bracket directly to the substructure By doing this, it is the most common construction method for placing PC girders in place (see Non-Patent Document 1, for example).

  In the construction method using fixed support area, it is necessary to hold the bridge body without detrimental deformation from concrete placement to prestressing. It is very important to decide.

  This technology has a problem in that it requires a large number of man-hours to assemble and remove the support work, and requires the construction of a foundation for the fixed support work.

  For this, there is an erection method using a moving support (for example, see Non-Patent Document 2). An erection method using a moving support is a fixed support erection method using a general frame support. On the other hand, it is a construction method in which the formwork and supporting work are only partially disassembled and moved to the next diameter, and the bridge body is constructed one by one in order, which is advantageous for multi-span bridges of a certain size or more. It is a construction method.

  This method was developed to save labor for bridges and construction work with high-leg bridges, which are difficult to construct with fixed support from the ground. In addition to rapid construction and labor saving, it has been confirmed that it has been confirmed that it can reduce economic problems and troubles in traffic used in under-sparing spaces and can be constructed safely. Furthermore, since it is an all-weather type, it is easy to level labor, and it leads to an improvement in quality due to the advantage of repeated work. Although there are differences depending on ground conditions, support work height, etc., it is generally said that a construction extension of 600 to 800 m is economically advantageous compared to fixed support work.

    This construction method can secure the space under the bridge body at the time of construction, and can be constructed without being influenced by the situation of the under-girder space. Since the bridge is covered with a roof, it can be constructed without being affected by weather conditions such as wind and rain, and process management is easy. Since the same work is continued, the skill level of the worker is fast, and labor saving and rapid construction are possible by mechanization and the quality is improved. The construction can be done quickly, safely and reliably, and the economy will improve as the construction scale increases.

This construction method is used when the construction extension is long because the scale of the erection facility is larger than the fixed support work and the cost of the equipment is high.
PC Construction Technology Association: "PC Bridge Construction Method" 2002: p57-62 PC Construction Technology Association: "PC Bridge Construction Method" 2002: p71-78

  In the construction of the continuous viaduct in the present invention, a simple temporary girder is used to connect the lifting formwork from below without assembling a large-scale fixed support from the ground and without using a heavy equipment moving support. Thus, the object is to provide a technology for supporting a temporary girder and receiving a formwork by a column (movable support) that receives a concrete load at the time of placing the concrete and simply constructing a continuous viaduct.

This invention is made | formed in order to solve the said problem, and consists of the process of following (a)-(g), It is the construction method of the continuous high bridge | crosslinking characterized by the above-mentioned.
(A) A suspension girder along the bridge axis direction is provided on the side, and a temporary girder in which a lifting device is suspended on the suspension rail is placed.
(B) A bridge body frame having a unit length in the bridge axis direction is conveyed downwardly across the span by another conveying device.
(C) The bridge frame is lifted by the lifting device, suspended from the temporary girder, and sequentially connected to assemble one span.
(D) Auxiliary struts for receiving a concrete load are erected at the intermediate portion in the bridge axis direction of the formwork between one diameter.
(E) A concrete bridge is placed in the formwork between one diameter or a plurality of diameters, and after curing, prestress is introduced and connected to an existing bridge body.
(F) The auxiliary strut is removed, the formwork of the axial unit length is sequentially lowered by the lifting device, and is transported between the next construction diameters.
(G) The temporary girder is advanced, and the above steps (b) to (f) are repeated.

  In the construction method of the continuous viaduct, according to the width of the bridge body, one or more auxiliary girders that are long in the bridge axis direction are provided in the middle part of the bridge body width direction between the lower surface of the formwork and the upper surface of the auxiliary column. For example, a wide bridge with a width of 15 m or more can be easily constructed, which is preferable.

According to the present invention, there are the following effects as compared with the conventional fixed support.
I. Less affected by the condition of the ground.
B. Stable process control and shortening of work period can be done.
C. Work is simple and safe and easy.
D. It can save labor.

  As a result, there is an excellent effect that the construction period of continuous viaduct can be shortened and the cost can be reduced.

  First, the prior art will be described.

  15 is a side view showing a construction process of continuous viaduct using a fixed support, FIG. 16 is a plan view taken along arrow XX of FIG. 15, and FIG. 17 is a plan view taken along arrow YY of FIG.

  The fixed support 110 is assembled between the piers 100a, 100b, 100c. As shown in FIG. 16, a foundation work 114 for erecting the fixed support work 110 is prepared in advance. The fixed support 110 fixes the lower end 113 of the pillar 112 on the foundation work 114, connects these many pillars 112 with a connecting material to form a frame, and, as shown in FIG. A plurality of form receiving beams 120 are placed on the top beam 111 along the bridge axis direction so as to be orthogonal to the bridge axis.

  A formwork 130 is assembled on the formwork receiving beam 120, and bridge body concrete is placed thereon. After the concrete is cast, the formwork 130 is removed, the fixed support 110 is disassembled, and moved to the next construction site. If there is a crossing road 140 or the like under the bridge, the beam 141 is handed over it, and a lid 142 is placed thereon to protect it, and the fixed support 110 is erected above it. In this case, the foundation work is designed differently from the normal foundation work 114.

  In the construction using the above-mentioned fixed support work, it takes time to create the foundation of the support work and to assemble and disassemble the support work. Cost.

  In contrast to the construction of continuous viaducts using such fixed supports, bridges using moving supports do not require the assembly and disassembly of the ground foundation and fixed supports required for fixed supports. There is no need to remove the receiving beam, assemble, disassemble, or transfer the formwork, and there are no restrictions on the conditions under the bridge.

  FIG. 18 illustrates a cross section of a bridge body showing a moving process by removing the formwork 220 of the construction of the bridge body 210 using such a moving support 200. From the moving support construction device 200 provided on the bridge body 210 in the direction of the bridge axis, the mold 220 is opened and lifted and moved, and the mold 220 is pulled up and closed at the next bridge body construction position. 210 concrete placement is performed.

  Although this mobile support device 200 is suitable for construction of a large-scale long bridge, a small-scale and relatively short-length bridge is excessively equipped and uneconomical.

  Next, embodiments of the present invention will be described with reference to the drawings.

  1 and 2 are diagrams showing a construction method of a continuous viaduct according to an embodiment of the present invention. FIG. 1 is a side view and FIG. 2 is a plan view thereof.

  As shown in FIGS. 1 and 2, a bracket 20 is attached to the sides of the piers 100 a, 100 b, 100 c,..., And a temporary girder 10 including a pair of left and right plate girders 11 is placed on the bracket 20. . The temporary girder 10 has a main body length extending between two diameters, and a hand girder is attached on the extension of the temporary girder 10 so as to be movable in the bridge axis direction. The temporary girder 10 has a portal crane 12 mounted thereon. Further, a suspension rail along the bridge axis direction is provided on the side, and the lifting device 13 is suspended on this suspension rail.

  A total of four lifting devices 13 are suspended by two suspension rails provided on the left and right sides of the temporary girder 10, and are movable along the suspension rail in the direction of the bridge axis. Also, a lifting chain or rope having a length reaching the ground below the bridge is provided, and the formwork 30 is lifted from the ground below the bridge by four lifting devices 13 in the front, rear, left, and right.

  The formwork 30 is a formwork (unit formwork) divided into unit lengths in the direction of the bridge axis so that the formwork 30 can be transported by the truck 40 or the like, and is transported under the bridge by the track 40 or the like. The four lifting devices 13 lift the four corners of the unit mold 30 and raise and lower the mold 30 by synchronizing the four lifting powers. Further, the traveling devices of the four lifting devices 13 travel in the bridge axis direction in synchronization. In this way, the mold unit 30 of the axial unit length can be moved up and down in a horizontal state, and can be moved in parallel to integrally connect the adjacent unit mold frames 30 to each other. At the same time, the unit formwork 30 is sequentially connected to form a bridge concrete formwork. The temporary girder 10 suspends and supports these molds 30 at the concrete placement position. The mold 30 is provided with this hanging steel rod.

  The unit molds 30 a and 30 b shown in FIG. 1 show a state suspended from the temporary girder 10. In this way, when the bridge frame form for one span is assembled, the auxiliary strut 50 that receives the load of the cast concrete supports the bridge axial direction intermediate part of the form frame between the piers.

  3 and 4 are a front view and a side view of the bracket 20 (stand) for supporting the temporary girder 10. The bracket 20 is attached to the side portion of the pier 100. The bracket 20 is formed by attaching a vertical member 21 to a pier by a steel rod 24 or the like that sews the pier 100, attaching a horizontal overhanging member 22 to the vertical member 21, and attaching an oblique member 23 that supports the overhanging member 22. Yes.

  The plate girder 11 of the temporary girder 10 is placed on the overhang member 22. On the upper part of the temporary girder 10, a formwork 17 of an end portion (wing portion) of the bridge body is attached.

  Further, a horizontal arm 14 is extended laterally outward from the temporary girder 10, and a suspension rail 16 is attached to the horizontal arm 14. The suspension rail 16 is provided along the bridge axis direction, and the lifting device 13 is suspended.

  FIG. 5 is a cross-sectional view showing a state in which concrete of the bridge body 80 is placed in the formwork 30 of the bridge body, and FIG. 6 is a cross-sectional view showing a state in which the formwork 30 after concrete curing is being lowered downward. . The state of the mold 30 shown in FIG. 6 is the same as that when the mold 30 is lifted from below.

  As shown in FIG. 5, the mold 30 fixes the transverse beam 31 on the lower surface of the mold to the plate girder 11 of the temporary girder 10 with a steel bar 32. A form panel 32 and a framework for supporting it are provided on the transverse beam 31.

  After the concrete curing of the bridge body 80, this is connected to the existing bridge body, and after introducing prestress, the mold 30 is disassembled into unit molds and lowered as shown in FIG.

  FIGS. 7 to 10 are side views showing another embodiment. The difference from the embodiment of FIG. 1 is that the temporary girder 10 is placed on a pedestal 60 raised from the ground instead of the bracket 20 and has two spans. That is, the bridge body concrete was constructed at the same time.

  FIG. 7 shows an example in which the temporary girder 10 is disposed on the strong support frame 60 so as to drive the bridge body concrete over two passes, and the formwork between the piers 100a and 100b. 30 attachment processes are shown. The process of attaching the mold 30 is the same as the process shown in FIGS.

  FIG. 8 shows a situation in which the temporary girder 10 to which the formwork is attached in FIG. 7 is advanced and the formwork is attached to the subsequent part. In this way, the bridge concrete is laid for two spans across the piers 100a, 100b, 100c.

  FIG. 9 shows a process of removing the portions 30a, 30b, 30c and the like of the bridge body concrete cured in FIG.

  Next, as shown in FIG. 10, the temporary girder 10 is advanced over the length of the piers 100c, 100d, and 100e, and the mold is attached again. Then, the bridge concrete for 2 passes is placed and the above is repeated.

  7 to 10 require a two-frame formwork, but the construction period of the bridge body can be remarkably shortened as compared with the embodiments of FIGS.

  Next, the process of lifting and lowering the mold according to the present invention will be described with reference to FIGS.

  11 is a front view showing the process of lowering the mold 30 after the concrete casting curing of the bridge body 80, FIG. 12 is a side view of FIG. 11, and FIG. 13 is the right half of FIG. The figure and the left half are BB arrow line views of FIG. 11 to 13 show the lowering process of the mold 30, but the lifting and lifting process is the same.

  As shown in FIG. 11, the mold 30 includes a frame and a vertical beam 34 that support a mold panel 33 on a horizontal beam 31. A vertical beam 35 is provided on the lower surface of the horizontal beam 31, and a suspended steel rod 32 extending upward from the vertical beam 35 is attached. This steel bar 32 is a steel bar for hanging and attaching the mold 30 to the plate girder 11 of the temporary girder 10.

  In the lifting device 13, the lower end of the chain or rope 15 is coupled to the end of the transverse beam 31 by a coupling portion 16. On the ground, a truck 40 that conveys the mold 30 is shown.

  FIG. 12 is a side view of FIG. 11 and shows a state in which a vertical beam 35 is provided below the end of the suspension beam 31 of the mold 30 and two lifting devices 13 are suspended near both ends. . Then, the two lifting devices 13 are synchronously moved to the left in the direction of FIG. 12 to move the mold 30 and place it on the loading platform 41 of the truck 40.

  13, the right half is an AA arrow view of FIG. 11, and the left half is an BB arrow view of FIG. 11.

  Three rows of transverse beams 31 for lifting are provided on the lower surface of the mold 30, and two rows of transverse beams 31 on both sides thereof are provided with coupling portions 36 that are engaged with the suspension chain or rope 15 of the lifting device 13 at both ends. ing.

  FIG. 14 shows an example in which the auxiliary longitudinal beam 70 of the formwork receiver is used when a wide bridge body is constructed by the method of the present invention. The auxiliary vertical beam 70 is interposed between the lower surface of the formwork receiving horizontal beam 31 and the upper surface of the auxiliary column 50, and supports the intermediate part in the bridge width direction of the formwork. A plurality of auxiliary vertical beams 70 may be provided in accordance with the width. The auxiliary vertical beam 70a shown in FIG. 14 has shown the state which moved to the next concrete placement position.

It is a side view which shows construction of an Example. It is a top view which shows construction of an Example. It is a front view of a bracket. It is a side view of a bracket. It is a bridge body cross section at the time of concrete placement of an Example. It is a bridge body cross section after concrete placement of an example. It is a side view which shows construction of another Example. It is a side view which shows construction of another Example. It is a side view which shows construction of another Example. It is a side view which shows construction of another Example. It is a cross-sectional view at the time of mold lowering. It is a side view of FIG. It is an AA arrow view (right half) and BB arrow view (left half) of FIG. It is a side view of the Example in case a width is wide. It is a side view of a prior art. It is a XX arrow top view of FIG. It is a YY arrow top view of FIG. It is a cross-sectional view of another prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Temporary girder 11 Plate girder 12 Portal crane 13 Lifting device 14 Horizontal arm 15 Chain or rope 16 Suspension rail 17 Formwork of a wing part 20 Bracket (frame)
DESCRIPTION OF SYMBOLS 21 Vertical member 22 Horizontal overhanging member 23 Diagonal material 24 Steel rod 30a, 30b, 30c Formwork 31 Horizontal beam 32 Steel bar 33 Formwork panel 34 Vertical beam 35 Vertical beam 36 Joint part 40 Track 41 Loading platform 50 Auxiliary support 60 Stand 70 , 70a Auxiliary vertical beam 80 Bridge body 100a, 100b, 100c, 100d, 100e Bridge pier 110 Fixed support 111 Top beam 112 Column 113 Lower end 114 Foundation work 120 Form receiving beam 130 Formwork 140 Crossing road 141 Beam 142 Lid 200 Move Supporting work 210 Bridge body 220 Formwork

Claims (2)

1. A construction method of continuous viaduct comprising the following steps.
   (A) A suspension girder along the bridge axis direction is provided on the side, and a temporary girder in which a lifting device is suspended on the suspension rail is placed.
   (B) A bridge body frame having a unit length in the bridge axis direction is conveyed downwardly across the span by another conveying device.
   (C) The bridge frame is lifted by the lifting device, suspended from the temporary girder, and sequentially connected to assemble one span.
   (D) Auxiliary struts for receiving a concrete load are erected at the intermediate portion in the bridge axis direction of the formwork between one diameter.
   (E) A concrete bridge is placed in the formwork between one diameter or a plurality of diameters, and after curing, prestress is introduced and connected to an existing bridge body.
   (F) The auxiliary strut is removed, and the formwork of the unit length in the bridge axis direction is sequentially lowered by the lifting device, and conveyed between the next construction diameters.
   (G) The temporary girder is advanced, and the above steps (b) to (f) are repeated.
2.   According to the width of the bridge body, one or a plurality of auxiliary girders that are long in the bridge axis direction are interposed between the lower surface of the formwork and the upper surface of the auxiliary column at the intermediate portion in the width direction of the bridge body. The construction method of the continuous viaduct of Claim 1 to do.

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