JPH0444543A - Column-beam connecting work for precast reinforced concrete structure - Google Patents

Abstract

PURPOSE:To arrange lower end beams in upper and lower two stages by a method in which after Y-directed beams are placed, the bent tips of L-shaped reinforcing bars are upwardly joined to the tips of X-directed lower end two- stage beams. CONSTITUTION:The ends of X-directed beams l are placed on the tops of precast or in-situ cast concrete columns 4 having projected colum reinforcing bars 5 on their upper parts. The ends of Y-directed beams 1' are placed on the tops of the columns 4 and lower end one-stage beams 2 and 2' are mutually lapped crossingly. Under the condition, The bent tips of L-shaped reinforcing bars 6 are upwardly joined to the tips of the lower end two-stage beams 3 of X-directed beams l. The strength of the column-beam joints can thus be raised.

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" The present invention relates to a column-beam joining method for precast reinforced concrete structures, particularly to improvements in beam bottom reinforcement.

"Prior Art 1 Problems to be Solved by the Invention" Conventionally, as a column-beam connection method for precast reinforced concrete structures in which the connection point of the beam reinforcement is provided at the center of the beam between the columns, the column head After placing the ends of a pair of precast beams in the X direction that are connected to each other by a single beam bottom reinforcement on top, the ends of a pair of similar precast beams in the Y direction are placed on top and the bottom reinforcements of the beams intersect. Next, a method of joining is carried out by arranging reinforcement at the top of the beam in both the X and Y directions and placing joint concrete at the column-beam joint.

However, in the conventional construction method, the XY force direction beams are orthogonal and the lower end reinforcements of each other are overlapped in a crosswise manner. When placing the beam, the beam got caught on the upper lower end reinforcement of the beam in the X direction, and the beam in the X direction could not be lowered to the specified position, so the lower end reinforcement of the beam in the I didn't get it.

Therefore, there were limitations such as the inability to apply it to high-rise buildings that require many beam reinforcements.

"Means for Solving the Problems" In order to solve the above-mentioned conventional problems, the present invention provides a method in which the lower ends of opposing joint end surfaces are connected by a continuous integral lower end-step part, and the lower end-step part The joint ends of a pair of precast reinforced concrete beams facing each other in the horizontal The joint ends of a pair of precast reinforced concrete beams facing each other in the horizontal , proposes a column-beam joining method for a precast reinforced concrete structure in which an L-shaped reinforcing bar is joined to the tip of the lower two-stage bar in the X direction with its tip facing upward.

"Function" When placing a beam in the X direction, the bottom two-step reinforcement in the X direction is provided with a short protrusion, so the bottom step in the X direction does not get caught on the bottom two-step reinforcement of the beam in the X direction. It passes through the gap between the tips, and as a result, the beam in the X direction can be placed on the column without any problem.

After placing the beam in the X direction, the lower end two-stage reinforcement in the X direction is connected to the tip of the L-shaped reinforcing bar with the bent end facing upward, so it is securely connected to the concrete poured at the column-beam joint afterwards. It will be established.

Therefore, by joining the L-shaped reinforcing bars to the tips of the two-stage lower end reinforcement of the beam in the X direction, it becomes possible to arrange the lower end reinforcement in two stages, upper and lower.

"Embodiments" Below, embodiments of the present invention shown in the drawings will be described.
A pair of precast reinforced concrete beams 1, 1 placed opposite each other at a required interval in the horizontal On the joint end surface above the step reinforcement 2, lower end two-step reinforcements 3, 3, each having at least the minimum protrusion length required for the connection, are installed when the beams 1' and 1' in the X direction, which will be described later, are arranged orthogonally. A short protrusion is provided so as not to overlap the lower end reinforcement.

A pair of precast reinforced concrete beams 1''1' placed opposite each other in the horizontal
connected by.

When joining the columns and beams, first, as shown in Fig. 1, the ends of the beams 1, 1 in the Then, place the ends of the beams 1' and 1' in the
Overlap them orthogonally.

When placing the beam 1'1' in the X direction, the lower end two-step reinforcing bars 3, 3' in the X direction are protruded in short lengths, so the lower end-step part 2' in the X direction is placed on the lower end two-step reinforcing bars 3'. Since the beams 1' and 1' in the X direction can be placed on the pillars 4 without any problem, the beams 1' and 1' in the X direction can be placed on the pillars 4 without any problem.

Next, in this state, the L-shaped reinforcing bars 6 are joined to the tips of the two-stage reinforcing bars 3, 3 at the lower ends of the beams 1, 1 in the X direction, respectively, by welding or jointing, with their bent ends facing upward.

After arranging the lower end reinforcements of beams 1 and 1' in both the X and Y directions in two stages, upper and lower, as shown in Figure 3,
Arrange upper end reinforcement 7 on 1' and connect the column and beam joints and beams 1 and 1.
'In addition to pouring joint concrete on top of ',
Joining concrete is poured integrally at the joint between the beams 1, 1 and 1' and 1'.

In addition, since the protruding tip of the columnar reinforcement 5 is kept at the top surface of the beam, the work of joining the lower end two-stage reinforcements 3, 3 and the L-shaped part 6 can be easily performed without the columnar reinforcement 5 becoming an obstacle. .

"Effects of the Invention" As described above, according to the present invention, when a beam in the Y direction is mounted, a short two-step lower reinforcement is provided between the joint end faces of the beam in the X direction, so that the beam in the Y direction is By overlapping the lower end single-stage reinforcement and the lower end double-stage reinforcement in the upper and lower two stages orthogonally to the lower end single-stage reinforcement of the beam in the X direction, the beam in the Y direction can be placed on the column head without any problem.

In addition, the lower end double-tiered reinforcement in the X direction has an L-shaped reinforcing bar connected to its tip, and its bent tip faces upward, so it is firmly fixed in the concrete poured at the joint of the column and beam, and can be used as a beam reinforcement. A reinforcing effect can be achieved.

Therefore, the strength of the beam-column joint can be strengthened without any restrictions by arranging the beam bottom reinforcements in two stages at the beam-column joint.

[Brief explanation of the drawing]

FIGS. 1, 2, and 3 are side views sequentially showing the beam-column joining process according to the present invention, and FIG. 4 is a side view showing the reinforcement state of a conventional beam-column joint. 1. Beam in the X direction, 1' ・Beam in the Y direction, 2.2'
・Single-stage reinforcement at the bottom end, 3,3' ・Two-stage reinforcement at the bottom end, 4
・ ・Column, 5. ・Column reinforcement, 6. ・L-shaped reinforcement. 7. Beam top end reinforcement. Patent applicant representative Figure 1 Figure 3

Claims (1)

[Claims] 1) The lower portions of the opposing joint end surfaces are connected to each other by a continuous and integral lower end single-stage reinforcement, and a short two-stage lower end reinforcement is provided protruding from the joint end surface above the lower end single-stage reinforcement in the horizontal X direction. The joint ends of a pair of precast reinforced concrete beams facing each other are placed on the head of the column, and then the lower end single-stage reinforcement and the lower end double-stage reinforcement are arranged in two consecutive upper and lower stages between the lower parts of the opposing joint end faces. The joint ends of a pair of precast reinforced concrete beams facing each other in the horizontal Y direction are placed on the head of the column, and the
A column-beam joining method for a precast reinforced concrete structure, characterized by joining an L-shaped reinforcing bar to the tip of a two-stage bar at the lower end of the direction with the bent part of the tip facing upward.