JPH0726432B2 - Joining method of half PC beam and beam - Google Patents

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a method for joining a half PC (precast concrete) beam and a post-cast concrete beam.

[Prior art]

The conventional method for joining half-PC beam and girder is as a half-PC beam, with multiple lower end reinforcements in the concrete beam body and surrounding the lower end reinforcements at regular intervals, with the upper part protruding to the upper surface of the beam body. With a square stirrup, the end of the lower end streak is used as an anchor with the large beam so that it projects from the end face of the beam body, and after setting this half PC small beam to the large beam, half PC The concrete was placed and joined to the joint end of the beam, the large beam of post-cast concrete, and the projection of the stirrup.

[Problems to be Solved by the Invention]

In the above-mentioned conventional half-PC beam having the conventional structure, if the protruding length of the lower end bar is short, it cannot be firmly fixed in the large beam, so that the lower end bar needs to be lengthened. However, when the protruding length of the lower end streak is long, when setting the half PC beam to the beam,
There is a problem that it becomes an obstacle and the work efficiency decreases. Also, for the SRC structure, the end of the protruding lower end bar is bent back in a U shape at the end face of the beam to secure the fixing length,
Although some have a shorter protrusion length, in this case as well, the difficulty of the setting work due to the protrusion from the joint end portion has not been solved, and a change in the structure or an improvement in the joining method has been desired. The present invention has been conceived from the above circumstances, the object is to solve the problem due to the end of the projecting lower end bar, whether the girder is reinforced concrete (RC) structure, steel frame reinforced concrete (SRC) , Half PC New half PC that can easily set and join beam
It is to provide a method of joining a small beam and a large beam.

[Means for Solving the Problems]

The present invention has been made to solve the above-mentioned problems of the prior art, and at the joint end of the concrete beam body, a cotter in which a female screw is embedded so that a male screw can be screwed is formed, and a plurality of cotters are formed. The lower PC stirrup in which the lower end streak of is buried and a plurality of stirrup with the upper part protruding from the upper surface of the beam is arranged
It is set on a post-cast concrete girder, and the male screw of the female screw is screwed into the girder side to project from the girder side of the concrete beam, and then the joint end and girder part of the half PC girder and the stirrup. The present invention provides a method for joining a half-PC beam and a girder, which is characterized in that concrete is placed on the projecting portion and the upper end streak portion.

[Action]

In the method of joining the half-PC beam and the girder according to the present invention having the above-mentioned configuration, since the lower end streak does not project to the wood mouth surface which is the joining end of the half-PC beam, it may be performed by an appropriate means such as a crane. After hoisting, you can easily drop it between girders. A female embedded in the cotter at the joint end is placed between the girders by placing the joint end of the half-PC beam on the frame of the girder, or by supporting the center with an appropriate support. When a male screw is screwed onto the screw and the male screw is projected to the girder side, concrete is placed on the joint end portion and the girder portion, and on the protruding portion and the upper end streak portion of the stirrup, The half PC beam is joined to the beam by the consolidation of this concrete.

【Example】

Next, the present invention will be described in detail based on an embodiment shown in the drawings. In the figure, 1 is a half-PC beam, and a plurality of lower end reinforcements 3 (two in this case) are arranged in parallel in a concrete beam body 2 in parallel, and these plurality of lower end reinforcements 3 are arranged at regular intervals. It has a quadrilateral stirrup 4 which surrounds and surrounds the upper surface of the frame body, and a plurality of cotters (two in this case) 5 are formed on the wood end surface which is the joint end, and each cotter 5 is formed. The female screw 6 is embedded at a desired position in such a manner that the male screw 6a can be screwed therein. The end portion 31 of the lower end streak 3 is bent upward, and the bottom portion of the female screw 6 and the head portion of the male screw 6a are both formed to bulge in an annular shape so as not to easily come off from the concrete. The girder 7 has a reinforced concrete structure and is provided with an upper end bar 8a, a lower end bar 3a and a stirrup 4a as usual. The half PC beam 1 and the girder 7 having the above-mentioned configuration are dropped between the two beam members 7 (only one of which is shown) by suspending the half PC beam 1 by an appropriate means such as a crane, and a joining end portion. Is placed on the form frame (not shown) of the girder 7 and
The central portion is supported by an appropriate support or the like (not shown), and the joint end portion is set to face the joint portion of the girder 7.
After that, the upper end streak 8 inserted in the stirrup 4 is laterally moved to pass the upper end streak 8a of the girder 7 to complete the bar arrangement. After setting the half PC girder 1 as described above, the male screw 6a is screwed into the embedded female screw 6 to project the male screw 6a from the concrete beam 2 to the girder 7 side. , Half PC
Concrete 9 for burying the joint end of the beam 1 and the beam 7, and the stirrup 4 and the upper end streak 8 is poured. The concrete 9 is also embedded in the cotter 5 and the male screw 6a protruding toward the girder 7 side is buried therein. Since 7 is integrated, even if a tensile force acts on the lower end side, this force can be resisted. In addition, as a method of embedding the female screw 6 in the cotter 5 formed on the mouth end surface of the half PC beam 1 so that the male screw 6a can be screwed, for example, as shown in FIG. , Fixing a cotter mold 5a made of wood or the like at a desired position of the mold 10 on the wood mouth surface, and temporarily fixing the female screw 6 to the top of the cotter mold 5a by an appropriate means, for example, a screw 5b, etc. There is a way to do it.
When the concrete beam body 2 is formed in this way, when the formwork 10 and the cotter mold 5a are removed after the concrete is solidified,
A female screw 6 is embedded in the bottom of the cotter 5 so that the male screw 6a can be screwed therein. By the way, although the above-mentioned embodiment is intended for RC girders, the present invention is particularly limited to RC girders because the same can be applied to SRC girders. is not.

【The invention's effect】

As described above, in the joining method of the half-PC beam and the girder according to the present invention, since the lower end streak does not project at the joining end portion of the half-PC beam, there is no obstacle when setting it on the girder. . For this reason, the work of setting the half-PC beam is facilitated and the work efficiency is improved. On the other hand, a female screw is embedded in the cotter provided at the joining end of the half PC beam, and a male screw is screwed into the female screw to project to the girder side.
When concrete is poured and solidified, the half-PC beam and girder are joined via female and male screws. In particular, the use of a screw in which the bottom of the female screw and the head of the male screw bulge in an annular shape further improves the anchoring effect, so compared to the conventional joining method in which the lower end streak was projected long. Also, it is comparable in terms of tensile strength.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an embodiment of the present invention in a vertical cross section, FIG. 2 is an explanatory view of the mouth end surface of a half PC beam, and FIG. 3 is an explanatory view showing a method for forming a cotter. 1 ... Half PC beam, 2 ... Concrete beam, 3, 3a
...... Lower end streak, 4, 4a ...... Stirrup, 5 …… Cotter, 5a …… Cotter type, 6 …… Female screw, 6a …… Male screw,
7 ... Large beam, 8,8a ... Upper end streak, 9 ... Concrete,
10 ... Formwork.

Claims (1)

[Claims] 1. A cotter in which a male screw is embedded in a female screw so that a male screw can be screwed is formed at a joint end of a concrete beam, and a plurality of lower end streaks are embedded, and an upper part projects from an upper face of the beam. A half-PC beam with multiple stir wraps lined up,
It is set on a post-cast concrete girder, and a male screw is screwed into the female screw to project it toward the girder side from the concrete beam body, and then the joining end and girder part of the half PC girder and the stirrup. A method for joining half-PC beam and girder, which is characterized by placing concrete on the projecting part and the upper end streak part.