JPH0751819B2 - Reinforcing bar joint construction method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for jointing reticulated reinforcing bars.

(Prior Art) A conventional reticulated reinforcing bar welded with a vertical reinforcing bar and a horizontal reinforcing bar is arranged at equal intervals over the entire length thereof, and one of the reticulated reinforcing bars (A) of the adjacent reticulated reinforcing bars in the joint portion has the same phase. The overlapping length L ≧ l + 5 cm and 15 cm so that the vertical rebar (a ′) of the other reticulated rebar (A ′) is positioned between the adjacent vertical rebars (a) and (a) and as shown in FIG. As described above, the two reticulated reinforcing bars (A) and (A ') were polymerized and connected. However, when the diameter of the reticulated reinforcing bar is increased, the bond length becomes remarkably short with respect to the cross section of the reinforcing bar, and therefore the possibility of bond split fracture increases. Therefore, as shown in Fig. 6, the overlapping length L ≧ 2l
Must be connected as +5 cm.

In the figure, (b) and (b ') are horizontal rebars of the above-mentioned braided rebars.

(Problems to be Solved by the Invention) In the above-described conventional method for joining reticulated ironware rebars, the vertical rebars (a) and (a ') approach each other at the joint portion, and the concrete cross section with respect to the cross section of the rebar decreases, resulting in concrete construction. Since the vertical rebars of the joint portion are arranged at a pitch greater than that of the reticulated rebars (A) and (A '), the amount of rebar in the joint portion increases.

The above tendency becomes more remarkable when the reticulated reinforcing bar has a large diameter.

Furthermore, as compared with the case of small-diameter rebars with the same bar arrangement pitch, the concrete cross section surrounded by adjacent vertical rebars becomes smaller, and the possibility that concrete will bear bearing fracture fracture increases. It is necessary to increase the bearing area.

(Means for Solving Problems) The present invention has been proposed in order to solve such problems, in which longitudinal and lateral reinforcing bars are welded together, and the bar arrangement interval of the joint portion is set to the remaining common part. One pair of braided rebars with double the inter-bar spacing should be superposed and connected so that the joints of one braided bar are located in the middle of adjacent joints of another braided bar. The present invention relates to a characteristic method for constructing a reticulated reinforcing bar.

(Operation) In the present invention, as described above, only the joint portion of the braided rebar has a rebar spacing twice as long as the rebar spacing of the remaining general portion, and the rebar joint of one braided rebar has the other braid In order to be located in the middle of the adjacent joint rebar of the reinforcing bar, since the one pair of reticulated reinforcing bars are superposed and connected, the rebar pitch of the reticulated joint part constituted by the present invention is the same. It is the same as the bar arrangement pitch of the general part other than the joint part of the braided bar.

(Effect of the Invention) As described above, according to the method of the present invention, the bar arrangement pitch in the joint portion of the braided bar becomes equal to the bar arrangement pitch of the remaining general portion, and in the case of the conventional joint construction method shown in FIG. Since it is twice as large as the conventional one, the concrete cross section does not decrease as in the past, the workability and filling of concrete are improved, and the vertical rebars in the joint are arranged at the same pitch as the rest of the general part. Since it is reinforced, the amount of rebar in the joint is 6th
This is a significant saving compared to the conventional case shown in the figure.

Further, according to the present invention, as described above, the rebar spacing of the joint portion of the reticulated bar is twice as large as that in the conventional case shown in FIG. 6, so that the concrete cross-sectional area between adjacent vertical bars is Doubled, which is advantageous for bearing pressure splitting.

(Examples) The present invention will be described below with reference to illustrated examples.

(P) and (P ') are vertical rebars (1) (1') and horizontal rebars (2)
(2 ') is welded vertically and horizontally, and the vertical rebar (1a) at the joint
(1a ') spacing, the vertical bars of the remaining general part (1),
It is a reticulated reinforcing bar having a distance (1 ') twice that of l.

Then, of the two reticulated rebars, the vertical rebar (1a) at the joint of one reticulate rebar (P) is adjacent to the vertical rebar (1'a) at the joint of the other reticulated rebar (P '). The two reticulated reinforcing bars (P) and (P ') are superposed and connected so as to be positioned in the middle of (1'a).

Since the illustrated embodiment is constructed as described above, the vertical reinforcing bars (1a) (1 ') of the joint portion of the reticulated reinforcing bars (P) (P') are formed.
The pitch of a) is the same as the bar arrangement pitch 1 of the general portion other than the joint portion of the reticulated reinforcing bars (P) and (P '). (See Fig. 2) Therefore, the pitch l of the vertical bars (1a) (1'a) at the joint of the reticulated reinforcement (P) (P ') becomes the pitch l / 2 in the case of the joint of the reticulated reinforcement by the conventional method. Since it doubles, the workability and filling of concrete are improved.

In addition, the vertical bars (1a) at the joints of reticulated bars (P) (P ')
Since (1'a) is laid out at the same pitch 1 as the rest of the general portion, the amount of reinforcing bar in the joint portion is greatly reduced as compared with the conventional case.

Furthermore, since the pitch of the vertical rebars (1a) (1'a) of the joint portion is twice as large as that of the conventional joint portion, adjacent vertical rebars (1
a) The cross-sectional area of the concrete part (C) between (1'a) is 2
Even when the reticulated reinforcing bars (P) and (P ') are formed of large diameter reinforcing bars, it is advantageous for the bearing pressure splitting due to the compressive force received from the vertical reinforcing bars (1a) and (1'a). (See FIGS. 3 and 4)

[Brief description of drawings]

FIG. 1 is a perspective view showing an implementation state of an embodiment of a method for jointing reticulated reinforcing bars according to the present invention, and FIG. 2 is a cross-sectional plan view of a joint portion of reticulated reinforcing bars constituted by the jointing method according to the present invention. FIG. 4 and FIG. 4 are explanatory views showing the state in which the bearing pressure splitting of the concrete portion in the joint portion occurs, respectively, and are horizontal cross-sectional plan views and longitudinal sectional views, and FIGS. 5 and 6 are joint portions of conventional braided reinforcing bars, respectively. FIG. (P) (P ') ... reticulated rebar, (1) (1') ... vertical rebar, (1a) (1'a) ... vertical rebar at joint, (2)
(2 ') ... Horizontal rebar.

Front Page Continuation (72) Inventor Akira Ito 1-11-6 Nakamagome, Ota-ku, Tokyo Taisei Construction Dormitory (56) References Showa 59-78421 (JP, U)

Claims (1)

[Claims] 1. A pair of reticulated rebars, in which longitudinal and horizontal rebars are welded together and the rebar spacing of the joint portion is twice the rebar spacing of the remaining general portion, A method for jointing reticulated reinforcing bars, characterized in that the reticulated reinforcing bars are superposed and connected so as to be positioned in the middle of adjacent joint rebars.