JP2018053709A - Method for manufacturing precast segment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a precast segment using a match casting method which can suppress manufacturing costs.SOLUTION: A method is configured by comprising the steps of: previously manufacturing a precast half-finished member (101) formed by a web (11) and a lower floor slab (113) integrated with each other; arranging the precast half-finished member between an end frame (41) and the already produced precast segment so that a clearance (L) is formed between a lower floor slab of the precast half-finished member and the lower floor slab (13) of the already produced precast segment (1); and placing concrete inside a frame (42) for an upper floor slab assembled at a predetermined location surrounding an upper end part (11d) of the web of the precast half-finished member to manufacture the upper floor slab integrally molded with the precast half-finished member, as well as placing high strength mortar (M) in said clearance to be integrated into the lower floor slab of the already produced precast segment.SELECTED DRAWING: Figure 10

Description

  The present invention relates to a method for producing a precast segment, and in particular, a plurality of upper floor slabs and lower floor slabs made of concrete, and provided at a distance from each other in the bridge axis direction, and a plurality of the upper floor slab and the lower floor slab are connected to each other. The present invention relates to a method for manufacturing a precast segment constituting a part of a bridge girder of a bridge girder provided with a web.

  Conventionally, when a concrete box girder bridge is erected, a precast segment method is widely used in which precast segments previously divided and manufactured in a factory or on-site yard are integrated with each other at a bridge point. When precast segments are manufactured using the short line method, the joint surfaces of prefabricated precast segments that have been manufactured in advance are used as the formwork for the joint surfaces of precast segments that are adjacent to each other. Generally, a match cast method that matches the above is adopted.

  Further, as a box girder, there is known a box girder comprising an upper floor slab and a lower floor slab made of concrete and a plurality of webs that are provided at intervals in the bridge axis direction and connect the upper floor slab and the lower floor slab to each other. (See Patent Document 1). As shown in FIG. 22, the box girder 51 described in Patent Document 1 is a continuous girder that is spanned between a plurality of bridge piers 52 or abutments (not shown). As shown in FIG. 23, the box girder 51 includes an upper floor slab 53 that is arranged substantially horizontally to form a roadbed, a lower floor slab 54 that is arranged below the upper floor slab 53 and substantially parallel to the upper floor slab 53, A pair of webs 55 that connect the upper floor slab 53 and the lower floor slab 54 to each other are provided, and the cross-sectional shape in the direction orthogonal to the bridge axis direction has a box shape. The upper floor slab 53 and the lower floor slab 54 are made of concrete, and the web 55 is made of a steel member or concrete.

  As shown in FIG. 24, the web 55 has a butterfly (butterfly) shape in which the length in the bridge axis direction gradually increases from the middle in the height direction toward the upper side 55a and the lower side 55b in a side view. The webs 55 adjacent to each other in the bridge axis direction are provided at a predetermined interval in the bridge axis direction. That is, the webs 55 adjacent to each other in the bridge axis direction are not joined to each other.

Japanese Patent No. 4005774

  When the precast segment of the box girder 51 described in Patent Document 1 is manufactured by the short line method using the match cast method, the form plate for the upper floor slab arranged so as to surround the upper side 55a and the lower side 55b of the web 55 manufactured in advance. By placing concrete in the form for the inner and lower floor slabs, the upper floor slab 53 and the lower floor slab 54 integrated with the web 55 are manufactured.

  Specifically, as shown in FIG. 25, the upper floor slab formwork and the lower floor slab formwork for forming one end surface in the bridge axis direction of the upper floor slab 53 and the lower floor slab 54, respectively. A plate bulkhead 61 and a lower floor plate bulkhead 62 are supported at predetermined positions by an upper floor plate support member 65 and a lower floor plate support member 66 installed on a bulkhead frame 64 fixed to the floor surface 63, respectively. To do. Next, the pre-manufactured precast segment 67 manufactured previously is used for the upper floor slab bulkhead 61 and the lower floor slab so as to be used as the end form forming the other end surface in the bridge axis direction of the upper floor slab 53 and the lower floor slab 54. It is arranged at a position separated from the bulkhead 62 by a predetermined distance. The pre-manufactured precast segment 67 is placed on a first carriage 69 that can move on a rail 68. Next, between the bulkhead 61 for the upper floor slab and the bulkhead 62 for the lower floor slab and the manufactured precast segment 67, the mold 70 for the lower floor slab, the web 55, and the mold 71 for the upper floor slab are arranged in that order. . The lower floor slab formwork 70 and the web 55 are placed on a second carriage 72 that can move on a rail 68. Then, concrete is placed in the lower floor slab form 70 and the upper floor slab form 71 to manufacture the lower floor slab 54 and the upper floor slab 53.

  However, in the conventional method for producing a precast segment as described above, two mold forms, ie, the lower floor form mold 70 and the upper floor form form 71, are used at the same time. There was a problem that work was troublesome. In addition, since two bulkheads, that is, the bulkhead 61 for the upper floor slab and the bulkhead 62 for the lower floor slab are used, the cost of the manufacturing equipment is high. Further, in order to firmly support the two bulkheads, the bulkhead frame 64 needs to have a strong structure. Therefore, the conventional method for producing a precast segment as described above has a problem that the production cost is high.

  This invention is made | formed in view of such a background, and it aims at providing the manufacturing method of the precast segment of the match cast system which can suppress manufacturing cost.

  In order to solve the above problems, the present invention provides an upper floor slab (12) and a lower floor slab (13) made of concrete and spaced apart from each other in the direction of the bridge axis, and the upper floor slab and the lower floor slab are connected to each other. A method of manufacturing a precast segment (1) constituting a part of a bridge girder of a bridge girder having a plurality of webs (11) to be connected, wherein the web and the lower floor slab (113) are integrated with each other. Producing a precast semi-finished product member (101), and supporting the end form (41) forming one end surface in the bridge axis direction of the upper floor slab in a predetermined position by supporting means (33, 37), Arranging the pre-manufactured precast segment (1) previously produced at a position spaced a predetermined distance from the end formwork to be used as a end form forming the other end surface in the bridge axis direction of the upper floor slab, A recast semi-finished product member, the wife form and the prefabricated precast segment, so that a gap (L) is formed between the lower floor slab of the recast semi-finished product and the lower floor slab (13) of the prefabricated precast segment. An upper floor slab form (42) for producing the upper floor slab together with the end formwork and the prefabricated precast segment, and an upper end (11d) of the web of the precast semi-finished product member. A step of assembling at a predetermined position, and placing the concrete inside the formwork for the upper floor slab to produce the upper floor slab integrated with the precast semi-finished product, and concrete or mortar (M) in the gap And integrated with either the lower floor plate of the precast semi-finished product member or the lower floor plate of the manufactured precast segment. A structure including the steps of.

  According to this configuration, since the precast semi-finished product in which the web and the lower floor slab are integrated with each other is manufactured in advance, the lower floor slab formwork and concrete placing work, and the upper floor slab formwork assembling work Etc. work becomes easy. Further, when the upper floor slab is manufactured, the lower floor slab wife formwork and the lower floor slab support member are not required, and the structure of the support means can be simplified, so that the cost of the manufacturing equipment can be suppressed. Moreover, the joint surface between the upper floor slabs of the precast segments adjacent to each other can be completely matched by match casting using an already manufactured precast segment. Furthermore, by placing concrete or mortar into the gap formed between the lower floor slab of the precast semi-finished product and the lower floor slab of the pre-fabricated precast segment, the concrete or mortar integrated into one lower floor slab The end surface of the other lower floor slab side completely coincides with the end surface of the other lower floor slab, and the joining surface between the lower floor slabs of the precast segments adjacent to each other can be completely coincided.

  Further, according to the present invention, in the above-described configuration, in the step of manufacturing the precast semi-finished product member, a plurality of locking members (16) are provided on one end surface (113a) in the bridge axis direction of the lower floor slab from the end surface. It embeds so that it may protrude and it can be set as the structure where the protrusion dimension from the said end surface of each locking member is below the width | variety of the said clearance gap in the position.

  According to this configuration, the concrete or mortar placed in the gap formed between the lower floor slab of the precast semi-finished product member and the lower floor slab of the prefabricated precast segment is locked by the locking member, and the precast semi-finished product It is firmly integrated into either the lower floor plate of the member or the lower floor plate of the prefabricated precast segment.

  Further, according to the present invention, in the above-described configuration, in the step of manufacturing the precast semi-finished product member, a plurality of alignment members (17) at different positions in the bridge axis perpendicular direction on one end surface in the bridge axis direction of the lower floor slab. ) Is embedded so as to project from the end surface, and the projecting dimension of each alignment member from the end surface is the same as the width of the gap at that position, and in the step of disposing the precast semi-finished product member, It can be set as the structure which abuts the alignment member to the lower floor slab of the pre-manufactured precast segment or the pre-cast semi-finished product member.

  According to this configuration, the precast semi-finished product member and the pre-manufactured precast segment can be easily arranged at a position where a predetermined plane alignment and longitudinal gradient are realized by bringing a plurality of alignment members into contact with the adjacent lower floor slab. can do.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the precast segment of the match cast system which can suppress manufacturing cost can be provided.

The front view of the precast segment manufactured by the manufacturing method of the precast segment of a 1st embodiment (A) Perspective view showing the web in the precast segment of FIG. 1, (B) Side view of the precast segment It is a schematic front view for demonstrating the manufacturing method of the precast segment of 1st Embodiment, and is a figure which shows the production method of a precast semi-finished product member Side view of precast semi-finished product The schematic side view which shows the manufacturing equipment used for the manufacturing method of the precast segment of 1st Embodiment. The schematic side view for demonstrating the manufacturing method of the precast segment of 1st Embodiment. The schematic side view for demonstrating the manufacturing method of the precast segment of 1st Embodiment. The schematic side view for demonstrating the manufacturing method of the precast segment of 1st Embodiment. Enlarged view inside broken line circle IX in FIG. The schematic side view for demonstrating the manufacturing method of the precast segment of 1st Embodiment. The schematic side view for demonstrating the manufacturing method of the precast segment of 1st Embodiment. The figure which shows the modification of the manufacturing method of the precast segment of 1st Embodiment. The front view of the precast segment manufactured by the manufacturing method of the precast segment of 2nd Embodiment (A) Perspective view showing the web in the precast segment of FIG. 13, (B) Side view of the precast segment It is a schematic front view for demonstrating the manufacturing method of the precast segment of 2nd Embodiment, and is a figure which shows the production method of a precast semi-finished product member Side view of precast semi-finished product The schematic side view for demonstrating the manufacturing method of the precast segment of 2nd Embodiment The schematic side view for demonstrating the manufacturing method of the precast segment of 2nd Embodiment Enlarged view inside broken line circle XIX in FIG. XX arrow view in FIG. The figure which shows the modification of the manufacturing method of the precast segment of 2nd Embodiment. Side view of conventional bridge girder XXIII-XXIII sectional view of FIG. Enlarged view in broken line XXIV in FIG. Schematic side view for explaining a conventional precast segment manufacturing method

  Hereinafter, an embodiment of a method for producing a precast segment 1 according to the present invention will be described with reference to the drawings.

  First, a first embodiment of the present invention will be described with reference to FIGS. The manufacturing method of the precast segment 1 according to the present embodiment includes an upper floor slab and a lower floor slab made of concrete, and a plurality of webs that are provided at intervals in the bridge axis direction and connect the upper floor slab and the lower floor slab to each other. It is a manufacturing method for manufacturing the precast segment 1 which comprises a part of bridge axis direction of the provided bridge girder. A box girder 51 as shown in FIG. 22 can be configured by connecting a plurality of the precast segments 1 in the bridge axis direction at the bridge point.

  As shown in FIG. 1, the precast segment 1 extends horizontally so as to connect a pair of vertically extending webs 11 and the upper ends of the pair of webs 11, and an upper floor slab 53 (FIG. 22). (See FIG. 22). The upper floor slab 12 constituting a part of the bridge axis direction of the frame 11 and the lower floor slab 54 of the box girder 51 (see FIG. 22) extend horizontally to connect the lower ends of the pair of webs 11. It has the lower floor slab 13 constituting a part of the direction. The web 11, the upper floor slab 12, and the lower floor slab 13 are formed from high-strength concrete reinforced with, for example, steel fibers. The web 11, the upper floor slab 12, and the lower floor slab 13 may be made of reinforced concrete. Moreover, you may comprise the web 11 from a steel member.

  As shown in FIG. 2A, the web 11 has a butterfly (butterfly) shape whose length in the bridge axis direction gradually increases from the middle in the height direction to the upper side 11a and the lower side 11b in a side view. Yes. In the present embodiment, the web 11 has a butterfly shape in side view, but the shape of the web 11 is not limited to this, and the webs 11 of the precast segments 1 adjacent to each other are spaced apart from each other in the bridge axis direction. As long as they are spaced apart, the web 11 can have any of a variety of shapes.

  As shown in FIG. 1, the upper floor slab 12 and the lower floor slab 13 are formed in a substantially plate shape. The upper floor slab 12 is constructed so as to project laterally from each web 11. A thickened portion 12 a that protrudes downward is formed at a portion where the upper floor slab 12 is connected to the web 11. Similarly, a thickened portion 13 a that protrudes upward is formed at a portion where the lower floor slab 13 is connected to the web 11. Due to the thickened portion 12 a of the upper floor slab 12 and the thickened portion 13 a of the lower floor slab 13, the bonding strength between the upper floor slab 12 and the lower floor slab 13 and the web 11 is enhanced.

  On the lower surface of the upper floor slab 12, a cross beam 14 is formed at an appropriate position in the bridge axis direction (in the example of FIG. 1, at the center of each segment in the bridge axis direction). Further, as shown in FIG. 2, the one end surface 12b and the other end surface 12c in the bridge axis direction of the upper floor slab 12 are provided with a convex portion 15A and a concave portion 15B that constitute a shear key for increasing the shear force resistance of the bridge girder. Is formed. The convex portion 15A and the concave portion 15B are formed in complementary shapes. If desired, a shear key (not shown) may be formed at an appropriate position on the end surface 12 b of the lower floor slab 13. Although not shown, through holes for passing a PC cable for erection are formed in appropriate positions on the upper floor slab 12 and the lower floor slab 13 so as to penetrate in the bridge axis direction.

  A plurality of locking members 16 to be described later are embedded in one end surface 13b of the lower floor slab 13 in the bridge axis direction. The locking member 16 is covered with a high-strength mortar M having a predetermined thickness. In the present embodiment, four locking members 16 are embedded in each of the left and right thickened portions 13a of the lower floor slab 13 in two stages in the vertical direction.

The manufacturing method of the precast segment 1 according to the present embodiment includes the following steps.
(A) Step of manufacturing precast semi-finished product member 101 in which a pair of webs 11 and lower floor slab 113 are integrated with each other (B) Bulk for upper floor slab that forms said other end surface 12c in the bridge axis direction of upper floor slab 12 Step (C) of supporting the head 41 at a predetermined position by the supporting means (C) A precast segment manufactured previously (hereinafter referred to as “already manufactured”) to be used as the end form 12 for forming the one end face 12b in the bridge axis direction of the upper floor slab 12 (D) A precast semi-finished product member 101 is placed at a position spaced apart from the bulkhead 41 for upper floor slab by a predetermined distance. Between the bulkhead 41 for the upper floor slab and the prefabricated precast segment 1 so that a gap L is formed between them. Step (E) A step of assembling the upper floor slab formwork 42 for producing the upper floor slab 12 together with the upper floor slab bulkhead 41 and the prefabricated precast segment 1 at a predetermined position surrounding the upper end portion 11d of the web 11 of the precast semi-finished product member 101. (F) The concrete is placed in the form plate 42 for the upper floor slab to produce the upper floor slab 12 integrated with the precast semi-finished product member 101, and the high-strength mortar M is placed in the gap L to produce the pre-cast semi-finished product. Step of integrating with the lower floor plate 113 of the member 101

  First, (A) the step of manufacturing the precast semi-finished product member 101 in which the pair of webs 11 and the lower floor slab 113 are integrated with each other will be described with reference to FIGS. 3 and 4.

  The web 11 uses a precast concrete member manufactured in advance. A pretension is introduced into the portion of the web 11 to which a tensile load is applied using a PC steel material. As described above, the web 11 may be made of a steel member.

  As shown in FIG. 3A, the lower floor slab form 21 for manufacturing the lower floor slab 113 is assembled, and a pair of webs 11 are erected at predetermined positions on the lower floor slab form 21. Then, the lower floor slab 113 is manufactured by placing concrete so that the lower end portions 11c of the pair of webs 11 are buried in the form 21 for the lower floor slab. Thereby, as shown in FIG. 3 (B), the precast semi-finished product member 101 in which the pair of webs 11 and the lower floor slab 113 are integrated with each other can be manufactured.

  Then, as shown in FIG. 4, a locking member 16 having a locking projection at the tip is provided on one end surface 113 a in the bridge axis direction of the manufactured lower floor plate 113 of the precast semi-finished product member 101. It is embed | buried so that it may protrude from the said one end surface 113a with the protrusion dimension below the width W of the clearance gap L (refer FIG. 9). The protruding dimension is preferably about 10 mm. As the locking member 16, for example, a hexagonal bolt, an L-shaped bolt, a J-shaped bolt, or the like can be used. Note that the number and the embedded position of the locking members 16 can be changed as appropriate. For example, the locking member 16 may be embedded in the other end surface 113b of the lower floor slab 13 in the bridge axis direction. The locking member 16 may be assembled to the lower floor slab form 21 before placing concrete, and may be integrated with the lower floor slab 13 by placing concrete.

  Next, the manufacturing equipment 31 used in the process of manufacturing the precast segment 1 using the precast semi-finished product member 101 will be described with reference to FIG. As shown in FIG. 5, the manufacturing facility 31 includes a bulkhead frame 33 fixed to the floor surface 32, and a first carriage 35 and a second carriage 36 that are movable on rails 34 laid on the floor surface 32. It has. The bulkhead frame 33 is provided with a support member 37 for the upper floor slab for supporting the bulkhead 41 for the upper floor slab (see FIG. 6) that forms a wife mold for producing one end surface of the upper floor slab 12. . On the first carriage 35 and the second carriage 36, a plurality of hydraulic jacks 38 and a placing table 39 for placing the pre-manufactured precast segment 1 or the precast semi-finished product member 101 are installed. The mounting table 39 is supported by a plurality of hydraulic jacks 38, and the height and inclination angle of the mounting table 39 can be adjusted by each hydraulic jack 38.

  Next, steps (B) to (F) for manufacturing the precast segment 1 using the manufacturing equipment 31 shown in FIG. 5 will be described with reference to FIGS.

  First, as shown in FIG. 6, the upper floor slab bulkhead 41 for forming one end surface of the upper floor slab 12 in the bridge axis direction is supported at a predetermined position by the upper floor slab support member 37.

  Next, as shown in FIG. 7, the pre-manufactured precast segment 1 previously manufactured on the first carriage 35 is arranged at a position separated from the bulkhead 41 for upper floor slab by a predetermined distance (distance of about one segment). To do. The pre-manufactured precast segment 1 is disposed such that the locking member 16 embedded in the lower floor slab (hereinafter referred to as “manufactured lower floor slab”) 13 is located on the opposite side of the bulk head 41 for the upper floor slab. To do. Thus, the end surface 12c on the precast semi-finished product member 101 side of the upper floor slab (hereinafter referred to as “already manufactured upper floor slab”) 12 of the manufactured precast segment 1 is formed as the other end surface of the upper floor slab 12 in the bridge axis direction. It can be used as a match cast wife formwork. Note that the height and inclination angle of the pre-manufactured precast segment 1 are appropriately adjusted by the hydraulic jack 38.

  Subsequently, as shown in FIG. 8, the precast semi-finished product member 101 placed on the second carriage 36 has a gap between the lower floor slab 113 and the manufactured lower floor slab 13 of the manufactured precast segment 1. It arrange | positions between the bulkhead 41 for upper floor slabs, and the manufactured precast segment 1 so that L (refer FIG. 9) may be formed. Here, description will be made assuming that the gap L has a constant width W at any position in the left-right direction. In this case, the width W of the gap L is preferably about 20 mm. As shown in FIG. 9, in the gap L, the locking member 16 protrudes from the one end surface 113a of the lower floor slab 113 of the precast semi-finished product member 101 with a predetermined protruding dimension of a width W or less.

  Next, as shown in FIG. 10, the upper floor slab formwork 42 for producing the upper floor slab 12 together with the bulkhead 41 for the upper floor slab and the end surface 12c of the already manufactured upper floor slab 12 of the prefabricated precast segment 1 is precast semi-finished product member. 101 is assembled at a predetermined position surrounding the upper end portion 11d of the web 11.

  Then, concrete is cast inside the upper floor slab form 42 to manufacture the upper floor slab 12. Since the end surface of the prefabricated precast segment 1 side of the upper floor slab 12 is formed by using the end surface 12c of the prefabricated upper floor slab 12 of the prefabricated precast segment 1 as a matchcast frame, the prefabricated precast segment 1 is manufactured. It completely coincides with the end face 12c of the upper floor slab 12.

  Further, along with the placement of concrete into the upper floor slab form 42, a high-strength mortar M is placed in the gap L as shown in FIG. In place of the high-strength mortar M, concrete may be cast. The high-strength mortar M placed in the gap L is locked by the locking member 16 embedded in the one end surface 113a of the lower floor slab 113 of the precast semi-finished product member 101, and is firmly attached to the precast semi-finished product member 101. Integrated. The end surface Ma on the pre-manufactured precast segment 1 side of the high-strength mortar M integrated with the lower floor plate 113 of the pre-cast semi-finished product member 101 is completely the same as the end surface 13c on the pre-cast semi-finished product member 101 side of the pre-manufactured lower floor plate 13. Thus, the joint surfaces between the lower floor slabs 13 of the precast segments 1 adjacent to each other can be completely matched.

  In this embodiment, the high-strength mortar M placed in the gap L is integrated with the lower floor plate 113 of the precast semi-finished product member 101. However, the locking member 16 is the lower floor plate of the precast semi-finished product member 101. When the other end face 113b (see FIG. 4) of 113 is embedded, that is, as shown in FIG. 12, the locking member 16 is the precast semi-finished product member 101 of the prefabricated lower floor slab 13 of the prefabricated precast segment 1. When provided on the side end face 13 c, the high-strength mortar M cast in the gap L is integrated with the manufactured lower floor slab 13 of the manufactured precast segment 1. Also in this case, the end surface Mb on the precast semi-finished product member 101 side of the high-strength mortar M integrated with the manufactured lower floor slab 13 is the end surface on the prefabricated precast segment 1 side of the lower floor slab 113 of the precast semi-finished product member 101. 113a is completely coincident with each other, so that the joining surface between the lower floor slabs 13 of the precast segments 1 adjacent to each other can be completely coincident with each other.

  After the high-strength concrete cast in the upper floor slab form 42 and the high-strength mortar M cast in the gap L are cured, the pre-fabricated segment 1 is separated from the newly-prepared pre-cast segment 1 to a temporary storage place. Carry. And the next precast segment 1 is manufactured using the precast segment 1 newly manufactured as the pre-manufactured precast segment 1. By repeating the above steps, the precast segments 1 are sequentially manufactured.

  As described above, in the method for manufacturing the precast segment 1 according to the present embodiment, the precast semi-finished product member 101 in which the web 11 and the lower floor slab 13 are integrated with each other is manufactured in advance. In addition, operations such as concrete placing work and assembly work of the form of the upper floor slab 12 are facilitated. Further, when the upper floor slab 12 is manufactured, the lower floor slab bulkhead 62 (FIG. 25) and the lower floor slab support member 66 (FIG. 25) are not required, and the structure of the support means can be simplified. The cost of 31 can be suppressed. Further, the joint surface between the upper floor slabs 12 of the precast segments 1 adjacent to each other can be completely matched by match casting using the pre-manufactured precast segment 1. Further, by placing high-strength mortar M or concrete in the gap L formed between the lower floor slab 113 of the precast semi-finished product member 101 and the already manufactured lower floor slab 13 of the prefabricated precast segment 1, The end surface of the other lower floor slab 13 (113) side of the high-strength mortar M or concrete integrated with the floor slab 13 (113) completely coincides with the end surface of the other lower floor slab 13 (113) and is adjacent to each other. The joint surface between the lower floor slabs 13 (113) of the precast segment 1 can be completely matched.

  Further, the high-strength mortar M or concrete placed in the gap L formed between the lower floor slab 113 of the precast semi-finished product member 101 and the already manufactured lower floor slab 13 of the prefabricated precast segment 1 is retained by the locking member 16. The precast semi-finished product member 101 is firmly integrated with either the lower floor plate 113 of the precast semi-finished product 101 or the already manufactured lower floor plate 13 of the prefabricated precast segment 1.

  Next, a second embodiment of the present invention will be described with reference to FIGS. Elements common to the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  As shown in FIGS. 13 and 14, a plurality of locking members 16 and a plurality of alignment members 17 are embedded in one end surface 13 b of the lower floor slab 13 in the bridge axis direction. The alignment member 17 may be a concrete block, a mortar block, a steel material, or the like. While the locking member 16 is covered with the high-strength mortar M having a predetermined thickness, the alignment member 17 is exposed on one end face 13b of the high-strength mortar M in the bridge axis direction. In this embodiment, the two alignment members 17 are embedded in the left and right thickened portions 13a of the lower floor slab 13, that is, at different positions in the direction perpendicular to the bridge axis. The locking members 16 are provided in one row at seven locations perpendicular to the bridge axis, and are further provided in four locations so as to surround the alignment member 17 in the left and right thickened portions 13a.

  In the method for manufacturing the precast segment 1 according to the present embodiment, in the step (D) of disposing the precast semi-finished product member 101 of the above embodiment, the plurality of alignment members 17 are brought into contact with the lower floor slab 13 of the manufactured precast segment 1. Let Here, the width W of the gap L is not limited to a constant width in the direction perpendicular to the bridge axis. In a plan view, when the box girder 51 has a linear shape that curves, it is necessary to make the left length (the length in the bridge axis direction) and the right length of the precast segment 1 arranged in the curved portion different from each other. In such a case, since the lower floor slab 113 of the precast semi-finished product member 101 is manufactured with a certain size, the left and right lengths of the precast segment 1 are different from each other by making the width W of the gap L different from left to right. Make it.

  (A) In the step of manufacturing the precast semi-finished product member 101 in which the pair of webs 11 and the lower floor slab 113 are integrated with each other, as shown in FIG. 15 (A), the lower floor for manufacturing the lower floor slab 113 The plate mold 21 is assembled, and the alignment member 17 is arranged at a predetermined position so as to penetrate the lower floor mold 21 forming one end face 113a. The alignment member 17 is disposed so as to protrude from one end surface 113a with the same protrusion dimension as the width W of the gap L at that position, and is fixed so as not to be displaced. As shown in FIG. 15 (B), the precast semi-finished product member 101 in which the pair of webs 11 and the lower floor slab 113 are integrated with each other is manufactured by placing concrete and manufacturing the lower floor slab 113.

  Then, as shown in FIG. 16, a locking member 16 having a locking projection at the tip is provided on one end surface 113 a in the bridge axis direction of the lower floor plate 113 of the manufactured precast semi-finished product member 101. It embeds so that it may protrude from the said one end surface 113a with the protrusion dimension below the width W of the clearance gap L in the position.

  Next, steps (C) to (D) among steps for manufacturing the precast segment 1 will be described with reference to FIGS. 17 to 20. Steps (B) and (E) to (F) are the same as those in the first embodiment.

  In the step (C) of arranging the pre-manufactured precast segment 1, as shown in FIG. 17, the pre-manufactured precast segment 1 previously produced on the first carriage 35 is separated from the bulkhead 41 for upper floor slab by a predetermined distance (about It is arranged at a position separated by a distance of one segment. The pre-manufactured precast segment 1 is arranged so that the locking member 16 and the alignment member 17 embedded in the pre-manufactured lower floor slab 13 are located on the opposite side of the upper floor slab bulkhead 41.

  Subsequently, in the step (D) of arranging the precast semi-finished product member 101, as shown in FIG. 18, the two alignment members 17 have already produced the precast semi-finished product member 101 placed on the second carriage 36. It arrange | positions between the bulkhead 41 for upper floor slabs, and the manufactured precast segment 1 so that it may contact | abut to the other end surface 13c of the manufactured lower floor slab 13 of the precast segment 1. FIG. At this time, since the precast semi-finished product member 101 needs to be arranged at a fixed position with respect to the bulkhead 41 for the upper floor slab, the position of the manufactured precast segment 1 is adjusted. Further, the height and the inclination angle of the pre-manufactured precast segment 1 are appropriately adjusted by the hydraulic jack 38.

  Thus, a gap L is formed between the lower floor slab 113 of the precast semi-finished product member 101 and the manufactured lower floor slab 13 of the manufactured precast segment 1. As shown in FIGS. 19 and 20, in the gap L, the alignment member 17 protrudes from the one end surface 113a of the lower floor slab 113 of the precast semi-finished product member 101 in the same position as the width W of the gap L at that position. It protrudes with a dimension, and is in contact with the other end face 13c of the prefabricated lower floor slab 13 of the premanufactured precast segment 1. On the other hand, the locking member 16 protrudes from the one end surface 113a of the lower floor slab 113 of the precast semi-finished product member 101 with a predetermined protruding dimension equal to or less than the width W of the gap L at that position.

  In this embodiment, the high-strength mortar M placed in the gap L is integrated with the lower floor slab 113 of the precast semi-finished product member 101. On the other hand, the locking member 16 and the alignment member 17 may be embedded in the other end surface 113b (see FIG. 16) of the lower floor plate 113 of the precast semi-finished product member 101. That is, as shown in FIG. 21, the locking member 16 and the alignment member 17 may be provided on the end surface 13 c on the precast semi-finished product member 101 side of the prefabricated lower floor slab 13 of the premanufactured precast segment 1. Also in this case, the position of the manufactured precast segment 1 is adjusted so that the two alignment members 17 abut on the one end surface 113a of the lower floor slab 113 of the precast semi-finished product member 101.

  As described above, in the method for manufacturing the precast segment 1 according to this embodiment, in addition to the effects of the first embodiment, a plurality of alignment members 17 are brought into contact with the adjacent lower floor slab 113 or lower floor slab 13. Thus, the precast semi-finished product member 101 and the pre-manufactured precast segment 1 can be easily arranged at a position where a predetermined plane alignment and longitudinal gradient are realized.

  The description of the specific embodiments is finished as described above, but the present invention is not limited to these embodiments, and can be changed as appropriate without departing from the spirit of the present invention. For example, in the above embodiment, the bridge girder is configured as a single box girder bridge, but it is configured as a multi-main girder box girder bridge having two or more box-shaped cross sections, a multi-box girder bridge having continuous box-shaped cross sections, or the like. May be.

  Moreover, in the said embodiment, the cross-sectional shape of a bridge girder is set so that a pair of web 11 may extend substantially perpendicularly from the upper surface of the lower floor slab 13, and the upper floor slab 12 may protrude sideways from a pair of web 11. FIG. However, the pair of webs 11 have a cross-sectional shape reaching the upper floor slab 12 with a slight inclination angle so that the upper floor slab 12 extends upward from the upper surface or side edge of the lower floor slab 13. It is also possible to have a cross-sectional shape that does not protrude sideways. Further, the upper floor slab 12 may be positioned only above the pair of webs 11.

  In addition, the specific configuration, arrangement, quantity, shape, material, and the like of each member and part can be appropriately changed as long as they do not depart from the spirit of the present invention. On the other hand, all the components of the structure and procedure shown in the above embodiment are not necessarily essential, and may be appropriately selected.

1 Precast segment (Pre-manufactured precast segment)
11 Web 11d Upper end 12 Upper floor slab (Pre-manufactured upper floor slab)
13 Lower floor slab (Previously manufactured lower slab)
16 Locking member 17 Positioning member 33 Bulkhead frame 37 Upper floor support member 41 Upper floor bulkhead (wife frame)
42 Form for upper floor slab 101 Precast semi-finished product member 113 Floor slab 113a One end face L Crevice M High strength mortar W Width

Claims (3)

A part of the bridge girder of a bridge girder comprising a concrete upper floor slab and a lower floor slab, and a plurality of webs that are spaced apart from each other in the bridge axis direction and connect the upper floor slab and the lower floor slab to each other A precast segment manufacturing method comprising:
Producing a precast semi-finished product in which the web and the lower floor slab are integrated with each other;
Supporting the end form forming the one end face in the bridge axis direction of the upper floor slab at a predetermined position by support means;
In order to use as a wife formwork to form the other end surface of the upper floor slab in the direction of the bridge axis, a step of arranging the pre-manufactured precast segment previously produced at a position spaced apart from the wife formwork by a predetermined distance;
The precast semi-finished product member is disposed between the end form and the prefabricated precast segment so that a gap is formed between the lower floor slab and the prefabricated precast segment. Steps,
Assembling the upper floor slab form for producing the upper floor slab together with the wife mold form and the prefabricated precast segment at a predetermined position surrounding the upper end of the web of the precast semi-finished product member;
The upper floor slab is casted with concrete to produce the upper floor slab integrated with the precast semi-finished product member, and concrete or mortar is cast into the gap to form the precast semi-finished product member. And a step of integrating the lower floor slab with the lower floor slab of the prefabricated precast segment.   In the step of producing the precast semi-finished product member, a plurality of locking members are embedded on one end surface in the bridge axis direction of the lower floor slab so as to protrude from the end surface, and the protrusion of each locking member from the end surface 2. The method for producing a precast segment according to claim 1, wherein the dimension is equal to or smaller than the width of the gap at the position. In the step of manufacturing the precast semi-finished product member, a plurality of alignment members are embedded so as to protrude from the end surface at different positions in a direction perpendicular to the bridge axis on one end surface in the bridge axis direction of the lower floor slab. The protruding dimension of the mating member from the end face is the same as the width of the gap at that position,
2. The step of placing the precast semi-finished product member comprises bringing a plurality of the alignment members into contact with the adjacent prefabricated precast segment or the lower floor slab of the precast semi-finished product member. Item 3. A method for producing a precast segment according to Item 2.

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