JPS628297Y2 - - Google Patents

Description

[Detailed description of the invention] Since a flat concrete joint surface cannot transmit shear force, a so-called shear cotter is sometimes provided at the joint in order to integrate old and new concrete. When installing such a concrete turret, as shown in Figs. 1 and 2, a recess 2 or a protrusion 2' is provided on the splicing surface of the concrete 1 that is first poured, so that the concrete 3 to be spliced is It is often integrated into the concrete 1 via a convex portion 4 or a concave portion 4'.

In this case, the formwork is specialized to mold the recessed part 2 or the convex part 4, which increases the cost, makes it difficult to maintain construction accuracy, and makes it difficult to expect reliable transmission of shearing force. There are cases.

This project was proposed to solve these problems, and is characterized by a rectangular parallelepiped made of precast concrete buried in the uncured concrete surface so that a part of it protrudes. This relates to a concrete starter for pouring concrete.

In this project, as mentioned above, a rectangular parallelepiped made of precast concrete is manufactured in advance, and this is placed on the splicing surface of the first poured concrete while the poured concrete is in an uncured state. A part of the rectangular parallelepiped is made to protrude, so that shearing force can be reliably transmitted between the poured concrete and the concrete to be poured through the rectangular parallelepiped. In this way, according to this proposal, a caster is formed by simply partially embedding a pre-fabricated precast concrete rectangular parallelepiped into the pouring surface of the first poured concrete before the concrete hardens. However, not only is it easy to work with, but it can also be standardized and mass-produced, making it possible to provide high-quality charcoal starters at low cost.

In addition, by adjusting the concrete strength of the rectangular parallelepiped, it is possible to adjust the product strength, etc.
This proposal has many advantages.

The present invention will be described below with reference to illustrated embodiments.

5 and 6, reference numeral 11 is a rectangular parallelepiped made of precast concrete, and 11 is a rectangular parallelepiped made of precast concrete.
2, and after the concrete 12 hardens, concrete 13 is placed on the joint surface, and the old and new concrete 12 and 13 are integrated through the rectangular parallelepiped 11. It is something.

Figure 7 shows the case where this proposal is applied to the column joint part in the cast-in-place concrete method, and 14 is a beam,
Reference numeral 15 indicates a lower floor column, and reference numeral 16 indicates a floor slab.The precast concrete rectangular parallelepiped 11 is buried in the floor slab 16 at a position directly above the beam 14 in such a way that a part thereof protrudes upward when it is not yet cured. This is a continuation of the pillar 17 on the upper floor.

Figures 8 and 9 show the case where the present invention is applied to the joint between a beam and a deck slab in the PC construction method, and when forming the beam, a part of the rectangular parallelepiped 11 protrudes from the upper surface of the beam before the concrete hardens. A pair of precast concrete floor slabs 19 facing each other are placed on the precast concrete beams 18 buried in such a manner as to
The above-mentioned rectangular parallelepiped is sandwiched between the above-mentioned rectangular parallelepipeds, and concrete 20 is cast between each of the floor slabs 19 and the upper surface of the beam 18 to integrate the floor slab 19 and the beam 18.

In the figure, 21 is a recessed portion cut out in the floor slab 19.

Note that when the rectangular parallelepiped 11 is used in the PC construction method, a lifting hook 22, a scaffold, a handrail attachment part 23, etc. may be provided in advance, as shown in FIGS. 10 and 11, respectively.

[Brief explanation of the drawing]

Figures 1 and 3 are vertical cross-sectional views showing conventional shearcoasters for concrete pouring, Figures 2 and 4 are plan views thereof, and Figure 5 shows an embodiment of the shearcotor for concrete pouring according to the present invention. Fig. 6 is a plan view, Fig. 7 is a longitudinal sectional view showing an example in which the present invention is applied to a column joint of the cast-in-place concrete method, and Fig. 8 is a longitudinal sectional view showing an example in which the present invention is applied to a column joint of the cast-in-place concrete method. FIG. 9 is a longitudinal sectional view showing an embodiment applied to a pouring joint, FIG. 9 is a plan view thereof, and FIGS. 10 and 11 are slope views showing respective embodiments of a rectangular parallelepiped made of precast concrete. 11... Precast concrete rectangular parallelepiped,
12...The first concrete poured.

Claims (1)

[Scope of utility model registration request] A shear caster for concrete pouring is characterized in that a rectangular parallelepiped made of precast concrete is buried in an uncured concrete surface so that a part thereof protrudes.