JP2008063804A - Full precast concrete beam member and joint structure using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a full precast concrete beam member and a joint structure using the same, preventing joint reinforcement or the like from projecting from the upper face of the full precast concrete beam member. <P>SOLUTION: The full precast concrete beam member has flat steel embedded in the material axis direction of the upper face of the beam member. Shearing force transmission elements with a length reaching the inside of stirrup of the beam member are projected from the lower face of the flat steel. Full precast concrete slabs with joint reinforcements projected from the joint ends are placed in facing positions on the upper face of the full precast concrete beam member, and the joint reinforcements of the facing full precast concrete slabs are joined to each other. Shearing force transmission elements such as studs are projected from the upper face of the flat steel of the full precast concrete beam member, and cast-in-place concrete is placed between the full precast concrete slabs on the upper face of the full precast concrete beam member. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention belongs to the technical field of a joint structure between a full precast concrete beam member (hereinafter simply referred to as a full PCa beam member) and a full precast concrete slab (hereinafter simply referred to as a full PCa slab) using the same. More specifically, the present invention relates to a full PCa beam member that does not project any reinforcing bars or the like from the upper surface of the full PCa beam member, and a joint structure using the full PCa beam member.

  Conventionally, a beam member and a joint structure used for joining a full PCa beam member and a full PCa slab use a beam member having a structure in which a reinforcing bar which is a shear key for integrating the beam and the slab is protruded from the upper surface of the beam. In addition, a structure in which cast-in-place concrete is cast and joined between the beam upper part and the slab is disclosed and widely used.

  For example, Patent Document 1 uses a full PCa beam member formed by exposing an upper portion of an inverted U-shaped reinforcing bar perpendicular to the longitudinal direction of the upper surface of the beam member (see FIG. 20 of Patent Document 1). A structure is disclosed in which the full PCa beam member and the slab are joined after joining the joining bars protruding from the left and right slab ends.

  Further, in Patent Document 2, a full PCa beam member in which a headed stud is protruded from the upper surface of the beam member is used, the stud is disposed between full PCa slabs, and a joining bar protruding from between the slabs and the stud. The structure which united by the cast-in-place concrete is indicated.

  The beam member having a configuration in which a headed stud is protruded from the upper surface of the beam disclosed in Patent Document 2 is not only a full PCa beam member but also a half precast beam (Patent Document 3) or a steel concrete beam (Patent Document 4). Are also disclosed.

JP 2002-161603 A JP 20062541 A JP-A-4-319154 JP-A-4-254646

  The techniques according to Patent Documents 1 to 4 have several problems. First, when performing the joining work (joint work) of the joining bars protruding from the left and right slab ends, the inverted U-shaped reinforcing bars and headed studs projecting upward from the beam upper surface, and the horizontal direction from the end of the slab The joining bars protruding in the direction interfere with each other, which is very troublesome and time consuming. In particular, in the full precast floor construction method that joins the full PCa beam member and the full PCa slab disclosed in Patent Documents 1 and 2, the advantages of shortening the construction period and the number of workers originally possessed by the same floor construction method are offset. There is a problem that it cannot be applied positively.

  Furthermore, since the reinforcing bars, studs, and the like protrude from the beam member surface, it takes time and effort to manufacture the mounting work and positioning work. Further, when transporting to the site or the like by a vehicle or the like, the efficiency is very poor because the method of loading and handling takes into account the protruding portion.

  The object of the present invention is to solve all of the above-mentioned problems, and a full precast concrete member that does not protrude a connecting reinforcing bar or the like from the upper surface of the beam member, can greatly improve the efficiency of the joining work, An object of the present invention is to provide a full precast concrete beam member and a joint structure using the same that realize a shortening of the work period, promote the standardization of the precast member, and are excellent in efficiency and economy during transportation.

  A further object of the present invention is to provide a full precast concrete beam member capable of improving the strength of the beam member by causing the flat steel embedded in the upper surface of the full precast concrete member to play the role of the upper end reinforcement. It is to provide a joint structure.

As a means for solving the problems of the background art described above, the full precast concrete beam member according to the invention described in claim 1 is:
A full precast concrete beam member,
A flat steel is embedded in the axial direction of the upper surface of the beam member, and a shear force transmitting element with a length reaching the inside of the stirrup of the beam member is projected on the lower surface of the flat steel. To do.

The joint structure using the full precast concrete beam member according to the invention described in claim 2 is:
It is a joint structure between a full precast concrete beam member and a full precast concrete slab,
A flat steel is embedded in the axial direction of the upper surface of the full precast concrete beam member, and a shear force transmission element having a length reaching the inside of the stirrup of the beam member is projected on the lower surface of the flat steel, The full precast concrete slab is placed on the top surface of the full precast concrete beam member at the position where the full precast concrete slab protrudes from the joint end and the full precast concrete slab faces
The joint bars of the full precast concrete slabs that face each other are joined together, and a shear force transmission element such as a stud protrudes on the upper surface of the flat steel of the full precast concrete beam member,
In-situ concrete is cast between the full-precast concrete slabs on the upper surface of the full-precast concrete beam member, and the full-precast concrete beam member and the full-precast concrete slab are joined in an integral structure. To do.

The joint structure using the full precast concrete beam member according to the invention described in claim 3 is:
It is a joint structure between a full precast concrete beam member and a full precast concrete slab,
A flat steel is embedded in the axial direction of the upper surface of the beam member, and a shear force transmitting element with a length reaching the inside of the stirrup of the beam member is projected on the lower surface of the flat steel, and the shear force is also applied to the upper surface. The full precast concrete slab having a structure in which a transmission element is protruded and having a through hole in the thickness direction at the joint end on the upper surface of the full precast concrete beam member is formed in the through hole of the full precast concrete slab. It is placed so that the shearing force transmitting element protruding on the upper surface of the precast concrete beam member is included, and is placed with a certain gap between the concrete slabs,
The full precast concrete slab is filled with mortar in the through holes and gaps, and the full precast concrete beam member and the full precast concrete slab are joined in an integral structure.

The invention according to claim 4 is the full precast concrete beam member according to claims 1 to 3 and the joint structure using the same.
The flat steel embedded in the upper surface of a full precast concrete beam member should be arranged as a single plate over the entire width and length of the beam upper surface, or one piece at the center position, or a plurality of them at intervals in the width direction. It is characterized by.

The invention according to claim 5 is a joining structure using the full precast concrete beam member according to claim 3,
The through-hole provided in the joint end part of the full precast concrete slab is formed in the truncated cone shape which swells downward.

Invention of Claim 6 is in the joining structure using the full precast concrete beam member as described in any one of Claims 2-5,
A wave-shaped cotter is formed at the joint end of the full precast concrete slab.

  According to the fully precast concrete beam member according to the first aspect of the invention, a flat steel is embedded in the axial direction of the upper surface of the beam member, and the length reaches the inside of the stirrup of the beam member on the lower surface of the flat steel. Since the shear force transmission element is projected, it has a simple shape such as a rectangular parallelepiped with no connecting reinforcing bars at the top of the beam, making it easy to manufacture precast members and dramatically improving transport efficiency. . Not only can standardization of precast members be promoted.

  According to the joint structure using the full precast concrete beam member according to the inventions according to claims 2, 4, and 6, the slab end portion is formed in a state where no shear key such as a reinforcing bar or a stud is projected on the upper surface of the full precast beam member. Since the joint work with the joint bar can be performed, the problem of the interference between the shear key and the joint bar is eliminated, the efficiency of the joint work can be dramatically improved, and the construction period can be shortened. In other words, the advantages of the full precast floor method can be fully exhibited.

  In addition, flat steel was embedded in a strip shape in the direction of the material axis on the upper surface of the full PCa beam member, and a shear force transmission element with a length reaching the inside of the stirrup of the beam member was projected on the lower surface of the flat steel. The steel functions as a substitute for the so-called top bar that bears the axial force, and the amount of the top bar of the precast concrete beam member can be greatly reduced. Not only is it a flat steel, but it can weld studs, etc. on its upper surface, and can use the full precast slab (floor) method and deck plate method for steel beams, increasing the degree of freedom in selecting the floor slab method, Many advantages can be expected in terms of construction period.

  In the joint structure using the full precast concrete beam member according to the invention described in claims 3 and 5, the full precast concrete slab in which a through hole is formed at the joint end of the full precast concrete beam member is formed in the through hole of the slab. Since the configuration is such that the shearing force transmitting element is included, in addition to the effects of the above-described claims 2, 4, and 6, the slab is used as a scaffold for the operator except for the through holes, and shear force transmission is performed. There is an advantage that the element placement and the mortar filling operation can be easily performed.

  The beam member of the present invention is a full precast concrete beam member 1. A flat steel 2 is embedded in the direction of the material axis on the upper surface of the beam member 1, and a shear force transmitting element 3 having a length reaching the inside of the stirrup 41 of the beam member 1 is projected on the lower surface of the flat steel 2. It has been configured.

The present invention is preferably implemented in a joint structure between a precast concrete beam member 1 and a full precast concrete slab 6.
A structure in which a flat steel 2 is embedded in the axial direction of the upper surface of the full precast concrete beam member 1, and a shearing force transmission element 3 having a length reaching the stirrup 41 of the beam member is projected on the lower surface of the flat steel 2. Has been.
On the upper surface of the full precast concrete beam member 1, the full precast concrete slabs 6 and 6 with the joining bars 60 projecting from the end portions are placed at positions where they face each other.
The joint bars 60 of the full precast concrete slabs 6 and 6 that are opposed to each other are joined together, and a shearing force transmission element 9 such as a stud projects from the upper surface of the flat steel 2 of the full precast concrete beam member 1.
In-situ concrete is cast between the full precast concrete slabs 6 on the upper surface of the full precast concrete beam member 1, and the full precast concrete beam member 1 and the full precast concrete slab 6 are joined into an integral structure. It is a structure.

An embodiment of a full PCa beam member according to the present invention will be described with reference to FIG.
The full PCa beam member 1 is characterized by a structure in which the main reinforcement 40 and the stirrup reinforcement 41 are formed with a certain concrete cover, and the reinforcing bars, studs, and the like for joining are not projected from the surface of the beam member 1.

  As a specific configuration, first, a flat steel 2 is embedded in a strip shape in the direction of the material axis on the upper surface of the PCa beam member 1. In the illustrated example, the two flat steel bars 2 are arranged on the upper surface of the beam. However, the present invention is not limited to this. It is also preferable to embed flat steel 2 formed as a single plate extending over the entire width and length of the upper part of the beam (the invention according to claim 4).

Next, on the lower surface of the flat steel 2, the shearing force transmitting element 3 having a length reaching the inside of the stirrup 41 of the beam member 1 protrudes downward to complete the full PCa beam member 1. The shear force transmitting element 3 is specifically a headed stud, and is joined to the flat bar 2 by welding or the like. Of course, in addition to the stud, a shear key such as U-shaped steel or square rebar can be welded.
The flat steel 2 serves not only as a space for welding the headed stud 3 etc., but also serves as the upper end of the beam 1. Therefore, the amount of the upper end reinforcing bar of the full PCa beam member 1 can be greatly reduced.

As an example of the preparation procedure, when one or a plurality of flat bars 2 are arranged, a plurality of headed studs 3 are welded to the upper surface of the flat bar 2 in advance at a certain interval in the material axis direction. In addition, the rebar 5 and the flat steel 2 with the headed stud 3 facing downward are placed on the upper surface of the formwork. In this case, the concrete can be placed in the flat steel 2 using a gap between them.
At this time, it is preferable to bury the flat steel 2 at a depth such that the upper surface of the flat steel 2 is the same as the surrounding concrete surface.

  The full PCa beam member 1 has a rectangular cross section in the illustrated example, but is not limited to this, and can be implemented as an I-shaped cross section or a hollow cross section. In particular, the work efficiency can be further improved because the hollow cross section is lightweight. Moreover, the said structure is not limited to a reinforced concrete beam, It can apply similarly to a prestressed concrete beam member.

Next, a joint structure using the full precast concrete beam member according to the invention described in claim 2 will be described with reference to FIGS.
The present invention is suitably implemented for a joint structure between a full PCa beam member 1 and a full precast concrete slab 6 (hereinafter simply referred to as a full PCa slab).

  As described in the first embodiment, the full PCa beam member 1 has a length in which the flat bar 2 is embedded in the material axis direction on the upper surface thereof and reaches the inside of the stirrup 41 of the beam member 1 on the lower surface of the flat bar 2. The shearing force transmission element 3 is projected downward. Details are the same as described in the first embodiment, and a description thereof will be omitted.

On the upper surface of the full PCa beam member 1 having the above-described configuration, the two full PCa slabs 6 with the joining bars 60 projecting from the joining end portions are placed at positions where they face each other.
A wave-shaped cotter 7 is formed on the side surface of the end portion to be joined of the full PCa slab 6 and on the upper side of the full PCa beam member 1 (the invention according to claim 6).
The joint bars 60, 60 of the two full PCa slabs 6 that are opposed to each other are joined together by a joint 8, such as a hoop clip joint. It is preferable that the joint work of the joining bars 60 is performed by the method disclosed by the present applicant in Japanese Patent Laid-Open No. 2002-161603.
For example joint 8 is steel sleeve SV, fitted one steel sleeve SV every joint muscles 60 and 60, the bonding muscle 60 of the respective pair by press-fitting the wedge Wg in the hole SV ₁ of the sleeve SV Connecting.
A shear force transmitting element 9 such as a headed stud is joined by welding or the like on the upper surface of the flat steel 2 of the full PCa beam member 1 and between the joining bars 60 and 60. The shear force transmitting element 9 is not limited to this, and the above-described shear key or the like can be implemented.
Thereafter, on-site concrete is placed between the full PCa beam members 6 on the upper surface of the full PCa slab 6, and the full PCa beam member 1 and the full PCa slab 6 are joined.

Next, the joining structure using the full precast concrete beam member concerning the invention described in Claim 3 is demonstrated using FIG. 3A and B. FIG. The third embodiment has substantially the same technical idea as the second embodiment, and the difference will be mainly described below.
As described above, in the full PCa beam member 1, the flat steel 2 is embedded in the material axis direction on the upper surface thereof, and the shear force transmitting element 3 having a length reaching the inside of the stirrup 41 of the beam member 1 in the flat steel 2 is provided. Is protruded downward and the shearing force transmitting element 9 is protruded upward also on the upper surface.

On the upper surface of the full PCa beam member 1 having the above-described configuration, two full PCa slabs 6 'having through holes 61 formed in the thickness direction of the joint end portions thereof are opposed to each other, and the slab 6' The through hole 61 is placed on the upper surface of the flat steel 2 of the full PCa beam member 1 so as to include a shearing force transmission element 9 such as a headed stud protruding upward by welding or the like at regular intervals. The The through hole 61 of the full PCa slab 6 'is a so-called tapered hole, is a truncated cone-shaped empty wall, and is formed in an inverted truncated cone shape that narrows downward (narrow). The significance of this shape is to maintain the joined state between the full PCa slab 6 'and the full PCa beam member 1.
The full PCa slabs 6 'and 6' are placed with a certain gap 10 (joint) therebetween. The purpose of providing the gap 10 is to close the full PCa slabs 6 'and 6' facing each other by filling the gap 10 with mortar, and a cotter may be formed in the gap 10 for implementation. it can.

Thereafter, the through hole 61 of the full PCa slab 6 ′ and the gap 10 described above are filled with mortar, and the full PCa beam member 1 and the full PCa slab 6 ′ are joined.
In this joining structure, the slab 6 ′ is a scaffold for the operator except for the through hole 61. Therefore, there is an advantage that the placement of the shearing force transmitting element 9 and the filling operation of the mortar can be easily performed.

  Although the illustration of the joint structure of the present invention is omitted, the slab method using a deck plate can be carried out in the same manner as in the case of a steel beam. In this case, when fixing the deck plate to the beam, a fixing structure for the steel beam, such as stud welding from the deck plate or hot-plugging plug welding, can be used.

  Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments and can be implemented in various forms without departing from the gist of the present invention.

The cross-sectional view of the full precast concrete beam member according to the present invention is shown. A is an elevation view showing a second embodiment of a joint structure using a full precast concrete beam member according to the present invention. B is a plan view of A. FIG. A is an elevation view showing a third embodiment of a joint structure using a full precast concrete beam member according to the present invention. B is a plan view of A. FIG.

Explanation of symbols

1 Full precast concrete beam 2 Flat steel 3, 9 Shear force transmission element (headed stud)
5 Reinforcing bar 6 Full precast concrete slab 60 Joint bar 61 Through hole 7 Recess for cotter 8 Joint member 10 Clearance

Claims (6)

A full precast concrete beam member,
A flat steel is embedded in the axial direction of the upper surface of the beam member, and a shear force transmitting element with a length reaching the inside of the stirrup of the beam member is projected on the lower surface of the flat steel. A full precast concrete beam member. It is a joint structure between a full precast concrete beam member and a full precast concrete slab,
A flat steel is embedded in the axial direction of the upper surface of the full precast concrete beam member, and a shear force transmission element having a length reaching the inside of the stirrup of the beam member is projected on the lower surface of the flat steel, The full precast concrete slab is placed on the top surface of the full precast concrete beam member at the position where the full precast concrete slab protrudes from the joint end and the full precast concrete slab faces
The joint bars of the full precast concrete slabs that face each other are joined together, and a shear force transmission element such as a stud protrudes on the upper surface of the flat steel of the full precast concrete beam member,
In-situ concrete is cast between the full-precast concrete slabs on the upper surface of the full-precast concrete beam member, and the full-precast concrete beam member and the full-precast concrete slab are joined in an integral structure. A joint structure using fully precast concrete beam members. It is a joint structure between a full precast concrete beam member and a full precast concrete slab,
A flat steel is embedded in the axial direction of the upper surface of the beam member, and a shear force transmitting element with a length reaching the inside of the stirrup of the beam member is projected on the lower surface of the flat steel, and the shear force is also applied to the upper surface. The full precast concrete slab having a structure in which a transmission element is protruded and having a through hole in the thickness direction at the joint end on the upper surface of the full precast concrete beam member is formed in the through hole of the full precast concrete slab. It is placed so that the shearing force transmitting element protruding on the upper surface of the precast concrete beam member is included, and is placed with a certain gap between the concrete slabs,
The full precast concrete beam member is characterized in that mortar is filled in the through holes and gaps of the full precast concrete slab, and the full precast concrete beam member and the full precast concrete slab are joined in an integral structure. Had a joined structure.   The flat steel embedded in the upper surface of a full precast concrete beam member should be arranged as a single plate over the entire width and length of the beam upper surface, or one piece at the center position, or a plurality of them at intervals in the width direction. The full precast concrete beam member as described in any one of Claims 1-3 characterized by these, and a junction structure using the same.   The joint using the full precast concrete beam member according to claim 3, wherein the through hole provided in the joint end portion of the full precast concrete slab is formed in a truncated cone shape that swells downward. Construction.   The joining structure using a full precast concrete beam member according to any one of claims 2 to 5, wherein a wave-shaped cotter is formed at a joining end portion of the full precast concrete slab.

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