JPH031538Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a reinforcing bar spacer used when pouring concrete.

A conventional reinforcing bar spacer is, for example, a steel wire 1 whose surface is coated with a resin, as shown in FIG. Alternatively, as shown in Fig. 2, a circular hole 5 for inserting reinforcing bars is provided in the center of a ring 4 made of synthetic resin with an uneven surface formed on the outer circumferential surface, and is supported via a stay 6 protruding from the inner circumference of the ring. It is known that the insertion portion 7 of the reinforcing bar 2 is provided from the outer periphery of the ring 4 to the circular hole 5 in the center.

In each of these reinforcing bar spacers, the lower end of the spacer supported on the formwork 8 is exposed to the surface of the concrete after the formwork 8 is demolded when buried in concrete. Since all of these exposed parts are made of synthetic resin, even if rainwater adheres to these parts, water will not enter the concrete from these parts and will not have any effect on the reinforcing bars 2. It was considered.

However, the presence of exposed areas of synthetic resin on the surface of concrete, even if only slightly, means that synthetic resin is more susceptible to changes due to heat than concrete. causes deformation due to expansion and contraction,
As a result, as this phenomenon is repeated, a gap is created between the synthetic resin part and the concrete, which causes the problem of rainwater adhering to the concrete and causing water to enter the concrete and corrode the reinforcing steel. It turned out that it has. This problem arises especially in the case of concrete structures located in areas near the coast where the air contains salt, where the salt adhering to the structure is dissolved by rainwater and enters the concrete with water from the exposed synthetic resin parts. This is attracting attention as a very serious problem because it accelerates the corrosion of reinforcing bars.

The purpose of this proposal is to solve the above-mentioned problems with conventional reinforcing bar spacers.The reinforcing bars are supported by a synthetic resin locking plate, and the lower end of this reinforcing bar locking plate is It is characterized by being embedded in the upper surface of a mortar block whose bottom surface is formed in the shape of a ship's bottom in cross-section along its length, and whose bottom end is supported by line contact on the formwork.

To explain the embodiment of the reinforcing bar spacer according to the present invention shown in FIG. It consists of a mortar block 12 for fixing. The reinforcing bar locking plate 11 is made of a vertically long resin plate, and has a reinforcing bar insertion part 13 cut into a V-shape in the center of the upper edge, and a reinforcing bar insertion part 13 opened so as to communicate with the lower end of this insertion part 13. It has a general-purpose circular hole 14, and mortar blocks 1 are provided below both edges.
A locking groove 15 for the inside of 2 is provided.

On the other hand, the mortar block 12 has a bottom surface 16 shaped like a ship's bottom with a semicircular cross section along its length, and a bottom end 17 that can be in line contact with the formwork 18. The reinforcing bar locking plate 11 is inserted into the mortar block 12 by inserting the lower end of the locking plate into the mortar at a stage where the mortar has not yet hardened during the process of molding the mortar block 12 using a formwork not shown. By doing so, it is fixed integrally with the block 12.

The reinforcing bar spacer according to this invention has the above-mentioned shape, and when attached to the reinforcing bar 10, the reinforcing bar 10 is pushed into the reinforcing bar insertion part 13 as shown in FIG. Sides 13a, 13b
are expanded in opposite directions so that the reinforcing bar 10 can be inserted into the lower circular hole 14, and after the reinforcing bar 10 is inserted into the circular hole 14, both sides 1 of the insertion portion are expanded.
3a and 13b are closed again as shown in FIG. 3, so that the reinforcing bars 10 are securely inserted into the circular holes 14 in the reinforcing bar locking plate 11.

The mortar block 12 has a bottom end 17 of the bottom surface 16.
is supported by line contact on the formwork 18, so it has an unstable shape in itself, but after the reinforcing bar locking plate 11 is inserted into the reinforcing bar 10 as described above, Since the reinforcing bars 10 are disposed on the formwork 18 such that the bottom line contact surface is perpendicular to the axial direction of the reinforcing bars 10, the reinforcing bars 10 can be stably supported.
Furthermore, since this mortar block 12 is made of the same material as the concrete to be placed, it has good adhesion to the concrete and is closely adhered to the concrete without any gaps.

As described above, in this reinforcing bar spacer, the reinforcing bars 10 can be stably supported by the reinforcing bar locking plate 11, and the reinforcing bar locking plate 11 is supported by the mortar block 12, which is the same as concrete, and furthermore, after demolding, Since only a small area of the linear bottom end 17 is exposed on the concrete surface, the exposed linear bottom end 17 is not affected by deformation or the like due to changes in temperature. Therefore, when this reinforcing bar spacer is used, unlike conventional reinforcing bar spacers, there is no gap between the concrete and the reinforcing bar supporting member due to foreign matter exposed on the surface of the concrete. This has the effect of reliably preventing rainwater and salt from entering the concrete from the area and preventing corrosion of reinforcing bars over a long period of time.

[Brief explanation of the drawing]

Figures 1 and 2 are both perspective views showing the shape of a conventional reinforcing bar spacer, Figure 3 is a perspective view showing the shape of a reinforcing bar spacer according to the present invention, and Figure 4 is a sectional view taken along the - line in Figure 3. , FIG. 5 is a plan view showing the state of use. In the figure, 10: reinforcing bar, 11: reinforcing bar locking plate, 12: mortar block, 13: reinforcing bar insertion part, 14: circular hole, 1
5: Locking groove, 16: Bottom surface, 17: Bottom end, 18: Formwork.

Claims (1)

[Scope of utility model registration request] A reinforcing bar insertion part is formed by a V-shaped cut in the center of the upper edge on the upper surface of a mortar block whose bottom surface has a ship's bottom shape in cross-section along its length so that the bottom end can be in line contact with the formwork. A reinforcing bar spacer comprising a reinforcing bar locking plate made of soft synthetic resin having a circular hole for passing through the reinforcing bars that communicates with the lower end of the spacer, the lower end of which is embedded in the block and fixed and protruded.