JP2005163410A - Thrust construction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique of a thrust construction method for constructing a bridge in a shorter construction period without exerting an influence on a circumferential environment, such as traffic restriction, traffic jam, and noises. <P>SOLUTION: According to the thrust construction method, main girders are formed of precast concrete segments 21. Specifically the precast concrete segments 21 are connected to a tail end of an antecedent bridge girder 20a on a thrust work floor 10, and a predetermined number of precast concrete segments 21 to be thrust together in one body are connected together, followed by temporarily fixing the segments together at every several blocks by means of temporary prestressing steels. When the segments that are thrust together in one body are connected together to form a subsequent bridge girder 20b, prestress is introduced to the segments by continuous steels, and the subsequent bridge girder is advanced together with the antecedent bridge girder 20a in one body. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a bridge girder extrusion construction method.

  In general, there is an extrusion construction method as a technique for constructing a continuous bridge girder having a span length of about 150 m or more with a span of 30 to 60 m. In the conventional technology related to the extrusion construction method, bridge girders are sequentially formed on the ground behind one abutment by cast-in-place construction, and steel hand girders are attached to the end of the bridge girder for extrusion construction. In this case, since the bridge girder is manufactured by cast-in-place construction, each process of formwork, rebar work, and concrete work is required in the bridging process. Therefore, there is a problem that the construction period is long.

  On the other hand, it is necessary to minimize the period of traffic interruption etc. especially in construction such as three-dimensional intersections at intersections in urban areas, and rapid construction of bridge girders is desired. With the conventional extrusion construction method, it is difficult to shorten the construction period, and the influence on the surrounding environment such as traffic regulation, traffic congestion, and noise accompanying construction is inevitable.

  In the construction of bridge girders, there is a technology in which pre-cast concrete segments are joined to produce a main span for one span, and the bridge girder is used to transfer and bridge in the direction of the bridge axis or the direction perpendicular to the bridge axis (for example, Patent Literature) 1).

  This technique is a cross-linking technique using an installation girder and not an extrusion installation technique.

  Also, when constructing a three-dimensional intersection road at the intersection of the road, there is a technology that first forms a side girder, lifts it and places it on the pier, and connects and pushes the blocks of the central girder on this side girder. (For example, refer to Patent Document 2).

  This technique is a technique for connecting only the central spans, and is not a technique for extruding a bridge girder over the entire span.

  In addition, when forming a three-dimensional intersection of a road, a column is erected so that the upper surface is horizontal, and a girder for each span is placed on the movable frame and placed between the columns. There is a technique for forming a ramp by shortening (see, for example, Patent Document 3).

This technology is also a technology that uses precast concrete girders, but it is not a bridge girder extrusion method.
JP 2000-146716 A (page 2-3, FIG. 1) JP 2003-193405 A (page 2-4, FIG. 1) JP2003-27425A (page 2-6, FIG. 5)

  An object of the present invention is to provide an extrusion construction method for a bridge girder that can be constructed in a shorter construction period than a conventional construction method for construction of a bridge girder.

  In the present invention, the main girder is a precast concrete segment, the segment is sequentially connected to the tail end of the bridge girder to be extruded, and the required extruding segments are connected, and temporarily fixed with temporary PC steel every several blocks. 1 is an extrusion construction method of a bridge girder characterized in that pre-stress is introduced by integrating with an already constructed bridge body at a stage where bridges having a length of one extrusion are connected, and then pushed forward to advance.

  Further, it is more preferable that the precast concrete segment is a segment produced by a match cast method at the joint portion.

  The match cast method is a method for manufacturing a segment in which concrete of an adjacent segment is cast using the joining end surface of a pre-formed segment as an end face mold of the adjacent segment. The segments manufactured in this way have the same joint surface and do not require joint adjustment at all. If an adhesive is applied to the joining end face and press-bonded, there is a merit that it can be easily completely adhered and integrated.

  According to the present invention, since the extrusion erection is performed using the precast block, the bridge girder can be manufactured in advance. Therefore, it is possible to omit the work time of formwork, bar arrangement, and concrete work before extrusion at the cross-linking site, the push work can be carried out in the shortest period, and the cross-linking work period can be shortened remarkably. .

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  The present invention makes use of the excellent characteristics of the extrusion erection method and shortens the construction period, and the main girder is made of a precast concrete segment, omitting the formwork, reinforcement work, concrete placement and curing at the extrusion construction position. Extrusion construction method.

  FIG. 1 is an explanatory view of the present invention. A precast concrete segment 21a manufactured in advance is transported by a conveying device 32 such as a crane and is wholesaled on an extrusion work floor 10 as indicated by an arrow 33. As shown in the figure, the trailing bridge girder 20b is connected to the tail end of the preceding bridge girder 20a. The preceding bridge girder 20a and the subsequent bridge girder 20b are connected and integrated, and the connected bridge girder 20 is advanced on the pier 11 as shown by an arrow 12 to be bridged.

  In the present invention, the segment 21 is assembled by temporary fixing with temporary PC steel every several blocks, and is pre-stressed with continuous steel (main cable) at the stage where the trailing bridge girder 20b with a length of one extrusion is connected. Stress is introduced and integrated with the preceding bridge girder 20a.

  In the present invention, it is preferable to produce a segment by a match cast method at a joint portion between adjacent segments of the precast concrete segment 21. In this way, by applying adhesive to the joints of the segments and crimping the joints with PC steel, the joint surfaces can be matched exactly and the joints that are firmly bonded can be quickly constructed without any special joint treatment. be able to. Accordingly, the joint processing of the joints of the segments becomes extremely simple, the construction process is remarkably shortened, and the quality improvement can be easily achieved.

  2 is a plan view showing one embodiment of the present invention, FIG. 3 is a side view thereof, FIG. 4 is a front view of a precast concrete segment 21 installed, and FIG. 5 is a side view on both sides of the segment 21 in FIG. FIG. 6 is a side view of the trailer 50 for transporting the precast concrete segment 21, and FIG. 7 is a plan view thereof. The trailer 50 shown in FIGS. 6 and 7 transports the precast concrete segment 21 from the production site to the construction site.

  As shown in FIGS. 2 and 3, the precast concrete segment 21 carried by the trailer 50 into the work circle 42 of the truck crane 41 is placed on the extrusion construction base 10 by the truck crane 41 at the bridge site. As shown in FIG. 4, the precast concrete segment 21 has a drawer bracket 22 attached to the lower surface, and is placed on the skid 16 of the extrusion work floor 10 via the bracket 22. The precast concrete segment 21 is designed to have dimensions and weight that can be transported by the trailer 50. For example, the width is about 5 m, the longitudinal length of the bridge is 2.5 to 2.8 m, and the girder height is 2.5 to 2.8 m. The total width including the upper floor slab 23 is 12 to 15 m. The lateral upper floor slabs 23 on both sides, side walls 24 such as railings, and diagonal members 25 are attached to both sides of the precast concrete segment 21, and are tensioned and united with the PC steel material for lateral tension after applying the horizontal joints. This segment 21 is then connected to the tail end of the bridge girder 20a as shown in FIG. Sequentially, for example, three segments 21 connected to the tail end are tensioned and integrated with a PC steel rod. A joint material (such as non-shrink mortar) is applied to the joint. If the joint surface is a segment manufactured by the match cast method, it can be easily integrated by applying an adhesive such as an epoxy resin to the joint surface formed by match casting and tensioning it with a PC steel material.

  2 and 3 show a state in which the trailing bridge girder 20b composed of six precast concrete segments 21 is placed on the extrusion work floor 10. FIG. When the precast concrete segment 21 is connected and the succeeding bridge girder 20b reaches a predetermined length, for example, a length in the bridge axis direction of 30 m, the preceding bridge girder 20a shown in FIG. 1 and the main PC steel material are integrated. The extrusion hydraulic jack 14 supported by the reaction force support member 13 pulls the drawer PC steel material 15 and advances the connected precast block group (bridge girder 20).

It is explanatory drawing of the extrusion construction method of an Example. It is a top view of one example of the present invention. FIG. 3 is a side view of FIG. 2. It is a front view of the precast concrete segment currently constructed. It is the front view which attached the side upper floor slab to the both sides of FIG. It is a side view of the trailer which conveys the segment made from a precast concrete. FIG. 7 is a plan view of FIG. 6.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Extrusion work floor 11 Bridge pier 12 Arrow 13 Reaction force support member 14 Drawer jack 15 Drawer PC steel 16 Skid 20 Bridge girder 20a Leading bridge girder 20b Rear bridge girder 21, 21a, 21b Segment 22 Drawer bracket 23 Upper floor slab 24 Side wall 25 Slope Material 32 Conveying device 33, 34 Arrow 41 Truck crane 42 Working circle 50 Trailer

Claims (2)

  The main girder is a precast concrete segment, the segment is sequentially connected to the tail end of the bridge girder to be extruded and connected, the required extruding segments are connected, and temporarily fixed with temporary PC steel every several blocks. The bridge girder erection method is characterized in that pre-stress is introduced by integrating with a bridge girder of a length of length and then prestressed, and then pushed forward to advance.   The method for extruding a bridge girder according to claim 1, wherein the precast concrete segment is a segment in which a joint portion is manufactured by a match cast method.

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