JPH0439875Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a footrest that is attached to a concrete wall such as a manhole side wall.

(Prior art) For concrete walls, for example, the side walls of manholes,
A plurality of footrests are provided that protrude vertically so that people can easily go up and down. As shown in FIG. 3, there is a type in which the legs 2 of the footrest 1 are embedded and fixed in the concrete wall 3. part tip 2a
The structure allows the legs to be bent upward or downward to improve the embedment strength of the legs.

In order to bury this type of foothold 1 in the concrete wall 3, in the case of what is called cast-in-place, the foothold 1 is buried in the concrete wall 3 using formwork (not shown). After fixing it in place and pouring concrete, the formwork is removed to create the shape shown in Figure 3. On the other hand, a concrete wall 3 is made separately, and a recess is made in advance in the concrete wall 3. The legs 2 of the footrest 1 are inserted and temporarily fixed there, and mortar is injected into the space of the recess into which the legs 2 are inserted to finish, thereby attaching the footrest 1 to the concrete wall 3. There is also a way to install it.

(Problem to be solved by the invention) In the method described above, in which the footrest 1 is fixed by pouring concrete into the formwork, water contained in the concrete is removed during the hardening process. oozes out to the surface. However,
Generally, the concrete wall 3 of a manhole is a nearly vertical surface, but the footrest 1 is installed almost horizontally, and most of the seeping moisture tends to accumulate in the lower part 4 of the concrete around the embedded leg 2. ,
Accumulated moisture is discharged from the wall surface portion 4a of the lower portion 4 of the leg portion 2. For this reason, it takes a long time for the lower portion 4 to harden, resulting in poor adhesion to the leg portion 2.
Then, the mounting strength of the footrest 1 tends to deteriorate easily. Furthermore, when the worker places his or her feet on the footrest 1 after installation, the weight of the worker is applied to the leg 2 as a load, and in particular, the lower part 4 of the leg 2 receives a large pressing force. 4 may deteriorate and break the concrete, and there is also a risk that the attachment of the footrest 1 may become loose.

The purpose of the present invention is to prevent such deterioration of the embedded portion of the footrest and provide a safer footrest.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a footrest to be attached to a concrete wall, in which a rod-shaped leg is axially divided into an embedded part and an exposed part. It is characterized in that an annular flange having a tapered surface whose diameter gradually decreases toward the embedded portion is provided at the boundary between the two.

(Function) When the rod-shaped legs are embedded in order to attach the footrest to a concrete wall, the moisture contained in the concrete oozes out around the embedded part of the legs during the concrete hardening process. Even if moisture comes out, it easily flows to the outside due to the tapered surface of the annular flange, spreads to the outer peripheral edge of the flange, and is discharged.

Furthermore, when a worker places his or her feet on the attached footrest, force is applied to the flange connected to the concrete wall through the exposed portion.

(Example) Hereinafter, an example of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view of a footrest 10 of the present invention embedded in a concrete wall 11 of a manhole by casting on site. The rod-shaped leg portion 12 of the footrest 10 is divided into an embedded portion 12a and an exposed portion 12b, and an annular flange 13 having a truncated conical shape tapered on the embedded portion 12a side is provided at the boundary between the embedded portion 12a and the exposed portion 12b.
is formed. The footrest 10 is of a U-shaped type or a one-legged type, the tip of the embedded portion 12a is bent, and the material is iron or ceramic.

The leg portion 12 of the flange 13 is embedded in the concrete wall 11 so that its diameter-enlarged peripheral edge portion 13a is exposed on the surface of the concrete wall 11. The flange 13 may be integrally cast with the leg portion 12 or may be fixed to the leg portion 12 by welding or the like.
Ensure that it has an integrated structure.

By attaching the above-mentioned footrest 10 to the concrete wall 11, water that seeps out during the hardening process of the concrete is absorbed into the embedded leg 12.
Even if moisture accumulates in the lower portion 14 of the flange 13, the tapered surface of the flange 13 allows the moisture to flow downward, and spreads along the tapered surface.
Since it oozes out into a, it is dispersed over a wide area and discharged to the outside. Therefore, the concrete no longer deteriorates due to moisture accumulating in only one place as in the past. In addition, the load applied to the footrest 10 is
Since the force is received by the entire area of the flange 13, the force received by the concrete wall 11 is significantly reduced compared to a case where the flange 13 is not provided.

FIG. 2 shows another embodiment of the present invention, in which a recess 17a is formed in the manhole wall 17 when the leg part 16 of the footrest 15 is embedded in the manhole wall 17.
Insert the leg part 16 into the recess 17a and temporarily fix the leg part 16 into the recess 17a.
The leg portion 16 is embedded by injecting mortar into the space, and it is desirable that the truncated conical flange 18 in this case has a shape that follows the shape of the wall surface 19 in which it is embedded as much as possible. In this state, when the recess 17a is filled with mortar, the area exposed to air is small, so it is easy to fix and maintain the horizontal position, and the same effects as in the embodiment shown in FIG. 1 can be obtained.

(Effects of the invention) Since the invention is constructed as described above, when the footrest is attached to a concrete wall, the moisture generated around the legs when the concrete hardens can easily flow to the outside through the flanges. Since it is dispersed and discharged, the concrete hardens better and the adhesion between the legs and the concrete part improves. The tendency of the concrete under the legs to deteriorate is therefore reduced. Moreover, since the load applied to the footrest is also dispersed to the periphery of the flange, it is possible to obtain a footrest with high buried strength and high safety. Moreover,
Because the structure is simple, all you need to do is attach a flange.
One of the major features of this invention is that it can be manufactured at low cost.
It is one.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view of the footrest of the present invention embedded in a concrete wall, Figure 2 is a plan view of another embodiment, and Figure 3 is the case of a conventional footrest embedded in a concrete wall. FIG. 11... Concrete wall, 12a... Embedded part,
12b...Exposed part, 13...Flange.

Claims (1)

[Scope of utility model registration request] In footrests attached to concrete walls,
A foot characterized in that a rod-shaped leg is divided into an embedded part and an exposed part in the axial direction, and an annular flange having a tapered surface whose diameter gradually decreases toward the embedded part is provided at the boundary between the parts. Hanging equipment.