JPS6242988Y2 - - Google Patents

Description

[Detailed description of the invention] The bottom plate for prestressed concrete piles is usually called a pile cap.
To prevent foundation concrete from falling into the hollow part of prestressed concrete piles (PC piles),
When the pile head is closed or when the pile head is treated (in most cases, the pile head is trimmed according to the soil surface after driving the pile), a certain depth is left in the hollow part of the pile. In some cases, the concrete that is poured into the concrete acts as a catch plate to prevent it from falling. Conventional products are made of steel plates or FRP, and most of them are for the former, and are hung from the head of the pile and used to prevent loss of foundation concrete. The present invention belongs to the latter category. A PC pile with a pile head is 350mm from the cut surface of the head.
As the prestress of the pile is released, the hollow part of the pile must be reinforced with reinforced concrete of the same strength as the foundation concrete to a depth of 1.5 times the pile diameter. . (Ministry of Construction Common Specification Guidelines) In this case, the reinforced reinforced concrete in the hollow part of the pile becomes an extension of the foundation concrete, and is an important part of the reinforced concrete structure. In other words, when the outer diameter of the PC stake is 350 mm, the hollow part has a diameter of 220 mm.
With 6 13mm steel bars as the main reinforcement in the 220mm hollow part,
In addition, 9mm round steel reinforcement will be placed every 100mm, and concrete will be poured to a depth of approximately 520mm from the pile head. Therefore, the saucer installed inside the hollow cavity must not only be used to prevent loss of concrete, but also to prevent leakage of cement milk and fogging of reinforcing bars, with sufficient consideration given to reinforced concrete construction standards. . Conventional products, which are simply suspended from the pile head to prevent loss of concrete, do not take measures to prevent leakage of cement milk or prevent fogging of reinforcing bars, so there is no way to install such an important foundation. The standards cannot be met.

This invention is based on reinforced concrete construction standards.
In order to ensure a perfect wall, we developed a mortar base plate for buried concrete that is effective in preventing leakage of cement milk and retaining reinforcing steel fog in buried concrete poured after PC pile head treatment. It is related to.

The following explanation is given with reference to the drawings.

Conventional products are mainly made of iron plates or FRP, but the present invention is made of mortar, which is particularly compatible with reinforced concrete structures. Figure 1 is a construction drawing used to block the head of a conventional pile.
Figure 2 is a construction drawing when a conventional product is used as a tray for buried concrete. As shown in Figure 3, conventional products are made of iron or FRP plates that are bent in order to contact the inner wall of the pile, but due to the material, they cannot fit tightly to the inner wall of the pile, so they do not serve the purpose of preventing concrete loss. However, it cannot be expected to prevent leakage of cement milk. In addition, when pouring concrete, the main reinforcing bars used are unstable in maintaining their fog.

As shown in the plan perspective view of Fig. 4 and the cross-sectional view of Fig. 5, the bottom plate for buried concrete of the present invention has the inner diameter of the pile placed at the center of the thickness of the circular mortar flat plate 1, which is about 20 mm smaller than the inner diameter of the pile. Waterproof sheet 2 such as asphalt roofing which is about 80mm larger than
It is set in between. Since a large number of diagonal cut lines 4 are made on the outer circumferential portion 3 of the waterproof sheet 2 that protrudes from the circular mortar flat plate 1, when the mortar flat plate 1 is inserted into the hollow part 5 of the pile, the waterproof Due to its flexibility, the sheet 2
Since it is curved diagonally upward and in close contact with the
Leakage of cement milk from the buried concrete 7 can be completely prevented. Further, since several holes 9 are bored in the portion 8 of the waterproof sheet 2 which is sandwiched between the mortar, the mortar flat plate 1 and the waterproof sheet 2 are completely joined. In order to prevent cracks, wires 10 are arranged inside the mortar flat plate 1, and the ends of these wires protrude into the upper part 16 of the mortar flat plate, as shown in the construction cross-sectional view of the present invention in FIG. , this protruding reinforcement 11 is fixed and tightened at the lower end 13 of the main reinforcement 12 arranged in the buried concrete 7 at a position where a predetermined reinforcing bar cover 14 is maintained.
Rebar fog in reinforced reinforced concrete can be stabilized. As for the construction procedure for the product of this invention, instead of hanging it from the beginning on the head of the pile like in conventional products, we first attach the reinforcing bar cover 1 to the lower end 13 of the main bar.
4 is held, the tied mortar flat plate 1 is inserted into the hollow part 5 of the pile, and the upper part 15 of the main reinforcement is tied and fixed to the reinforcing bars of the foundation concrete, and then the embedded concrete 7 is poured. This eliminates shoddy work and construction errors, streamlines construction management, and satisfies reinforced concrete construction standards.

[Brief explanation of the drawing]

Figures 1 and 2 are construction sectional views of the conventional product, Figure 3 is a perspective view of the conventional product, Figure 4 is a plan sectional view of the invented product, and Figure 5 is a side sectional view of the invented product. It is. 6th
The figure is a cross-sectional view of the product according to the present invention. 1...Mortar flat plate, 2...Waterproof sheet,
3...Outer periphery of waterproof sheet, 4...Bevel cut line,
5...Medium part of stake, 6...Inner wall of stake, 7...
Embedded concrete, 8... Part of the waterproof sheet interposed in the mortar flat plate, 9... Perforation of the waterproof sheet, 10... Wire, 11... Protruding lines of the wire, 1
2...Main bar, 13...Lower end of main bar, 14...Reinforcing bar cover, 15...Top of main bar, 16...Top of mortar flat plate.

Claims (1)

[Scope of utility model registration request] A waterproof sheet such as asphalt roofing, which is larger than the inner diameter of the prestressed concrete pile, with many diagonal cut lines on the outer periphery, is placed flat in the center of a circular mortar plate smaller than the inner diameter of the pile. Bottom plate for embedded concrete of prestressed concrete piles.