JPS61270462A - Construction of reinforced concrete structure - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to an improvement in the method of constructing a high-rise reinforced concrete structure, particularly the method of constructing a beam portion thereof.

Problems to be Solved by the Invention Various prefabrication methods have been developed to save labor and improve quality when constructing reinforced concrete IJ structures. The PC beam construction method, in which the beams are highly prefabricated, is suitable for achieving the above objective, but the biggest problem is the connection between the PC beams.

For example, when connecting PC beams at the center, leave about 500 meters of concrete for the PC beams, weld the reinforcing bars together, construct stirrup bars for the beams, assemble formwork around them, and pour concrete. However, there are problems with welding workability, precision of reinforcing bars, and shrinkage due to welding.

Also, if PC beams are used in two directions, it will be difficult to fit the pillars together. In other words, the beams in one direction are set and then the beams in the other direction are set, but this method cannot be used if the lower end reinforcing bars are arranged in two stages. Therefore, the prefabrication rate is lower than that of the two-way PCC beam, so a one-way PC beam plan can be considered. In that case, the beams in one direction would be made of PC, and the reinforcing bars in the other direction would be erected on-site, but erecting reinforcing bars on-site would not shorten the construction period.

As mentioned above, it is difficult to connect reinforcing bars embedded in PC beams with each other. However, it is also difficult to assemble reinforcing bars on site when the PC beams are not connected to each other. Therefore, in this invention, the reinforcing bars of the beams perpendicular to the PC beams are lifted and assembled as prefabricated bars that are pre-assembled to the PC beam bars at a ground assembly yard.

Means to Solve the Problem The configuration that is the gist of the present invention is to use a precast reinforced concrete member, that is, a PC beam, as one beam, and assemble the reinforcing bars of the other beam in advance so as to be orthogonal to the one beam. As a unit member, this unit member is erected between the pillars, one of the PC beams is supported by shoring, and the reinforcing bars of the other previously assembled beam are placed within the beam form. Concrete will be poured and the columns and beams will be integrated.

Example A unit member A constituting a beam manufactured in advance at a construction yard is a continuous combination of beams in two directions, one of which is a precast reinforced concrete member (20 members), with reinforcing steel at the end. In addition, the reinforcing bars of the other beam 2 are preassembled so as to be perpendicular to the beam 1. This unit member A is formed in a T-shape, an I-shape, a square shape, etc. as shown in FIG. That is, the 20 member section has one span or two
The reinforcing bars of beam 2 will be connected at the middle of the span.

Note that the PC beam 1 has a structure in which the upper end reinforcing bars and the upper portions of the hoop bars are exposed.

During construction, the existing building frame B will be used and scaffolding C for replacement will be installed on the outside. Next, the prefabricated reinforcing bars 3 are hung onto the existing frame B, and the column forms 4 are erected. (Third,
(See Figure 4) Next, the beam formwork 5 for replacement is lifted up and replaced using the internal vertical space and installed on the existing frame (see Figure 5). First, the beam formwork 5 perpendicular to the PC beam 1 is is lowered and set, and the floor formwork 6 or thin PC board is installed using supports 7 if necessary. Next, column concrete is placed using the floor formwork 6 as a working floor. (See FIG. 6) Next, the unit member A, which will become a component of the beam, is suspended, and the PC member 1 is supported at a regular height by the support 8. (See Fig. 7) The reinforcing bars of the other beam 2 are connected, and then the beam form 5 is raised to its normal position (see Fig. 8). Next, concrete for the beam and floor is poured. (See Figure 9) The above steps are repeated in order to build the building to the required height.

Effects of the Invention This invention has the above-mentioned configuration, and when carrying out the replacement method of beam formwork when constructing a reinforced concrete structure, one side is made of PC beams and the other is made of pre-assembled reinforcing bars, thereby shortening the construction period and improving the construction time. This work succeeded in improving the workability of reinforcing bar connections in a well-balanced manner.

[Brief explanation of drawings]

Figures 1 a, b, G, and d are plan views of the unit members constituting the beam, and Figure 2 is a plan view of the arrangement of the unit members. Figures 3, 4, 5, 6, and Figures 7, 8, and 9 are elevational views showing an overview of the construction process. A... Unit member, B... Existing frame C... Scaffolding 1... PC beam, 2... Beam reinforcing bar 3... Prefabricated reinforcing bar for residential use, 4... Column formwork 5... Beam formwork,
6. Floor formwork, 7. Support 8. Shoring. Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] One of the beams is a precast reinforced concrete member, and the reinforcing bars of the other beam are pre-assembled and unit members assembled perpendicular to the one beam are erected between the columns and the one beam is supported by shoring; A construction method for a reinforced concrete structure characterized by placing the reinforcing bars of the other previously assembled beam within the beam formwork, and pouring concrete within the beam formwork.