JPH0322352Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to the tip structure of a tremie pipe for concrete pouring.

Traditionally, when constructing continuous underground walls, channel slabs, bridge legs, etc., concrete has traditionally been placed in water or muddy water.
There is a tremie method that uses a hollow cylindrical tremie pipe as a pouring device.

In this construction method, the concrete is washed with water and preventing the separation of constituent materials such as cement and aggregate is an important point in constructing high-quality concrete structures.

In this method, unhardened concrete is poured, so it is important to prevent the concrete from being washed away by water and the constituent materials such as cement and aggregate from separating, which is an important point in constructing high-quality concrete structures. Concrete was always placed in such a way that the tip of the tremie pipe did not separate from the surface of the concrete being poured.

By the way, in recent years, new concrete that suppresses separation in water, unlike conventional underwater concrete, has been developed and put into practical use. This concrete is made by adding a special admixture to increase the viscosity of the concrete to reduce separation in water, but when conventional tremie tubes are used, the following problems occur.

That is, concrete to which an admixture has been added has a high viscosity, so if the tip of the tremie tube penetrates the surface of the poured concrete, the concrete will not flow down and will not be discharged smoothly.

Therefore, it is necessary to place the tip of the tremie tube slightly away from the concrete surface where it is placed.

However, if pouring is carried out under these conditions, the poured concrete will fall almost vertically and will be ejected with a direct impact on the surface of the concrete that has already been poured, causing damage to the poured concrete. When disturbed and washed away by surrounding water, separation was promoted, causing a decline in the strength of constructed structures and contaminating the water, which could lead to pollution problems.

This invention was made in view of this background, and its purpose is to provide a tremie pipe tip structure that can alleviate separation during concrete placement and that causes less water pollution.

In order to achieve this purpose, this invention was developed to sequentially pour high viscosity concrete to which an admixture has been added at predetermined intervals from above the concrete that has already been poured in a hollow cylindrical tremie pipe for concrete pouring. In a hollow cylindrical tremie pipe for concrete pouring, a collision plate is provided at the tip of the tremie tube so as to be approximately perpendicular to its axial direction, and a side wall of the tip of the tremie tube is attached at multiple locations. It is characterized by having a semicircularly cut out outlet for the concrete.

Hereinafter, preferred embodiments of this invention will be described based on the accompanying drawings.

FIG. 1 shows an embodiment of the tip structure of a tremie pipe for pouring concrete according to this invention.

The tremie tube 10 shown in the figure is made of a hollow cylindrical steel tube, and a flat collision plate 12 is fixed to the distal end of the tremie tube 12 so as to be perpendicular to the axial direction. The collision plate 12 is cut out obliquely upward from the longitudinal side in a substantially semicircular shape,
A pair of concrete discharge ports 14 are formed with the collision plate 12 in between.

With the tremie tube tip structure configured in this way, when the tremie tube 10 is installed in water and concrete is poured, the concrete poured into the tremie tube 10 once collides with the collision plate 12. Afterwards, it is discharged outward from the discharge port 14 in a substantially horizontal direction.

Therefore, no direct impact is applied to the poured concrete surface, preventing disturbance of the concrete surface, preventing a decrease in the strength of the concrete structure, and preventing contamination of the surrounding water. In addition, the poured concrete is discharged from the discharge port 1.
4, it is discharged in a substantially horizontal direction, which allows for smooth discharge and is suitable for pouring over a wide range.

Figure 2 shows a second embodiment of this invention.
Its features are that four concrete discharge ports 14 are provided and the collision plate 12 is a cross-shaped flat plate.

Even with the tip structure constructed in this way, the same effects as in the above embodiment can be obtained, and since the poured concrete is discharged in all directions, the levelness of the poured concrete surface is improved. .

Figure 3 shows the third embodiment of this invention.
Its distinctive feature is that the collision plate 12 is bent into a substantially V-shape and provided with a slope that slopes toward the concrete discharge port 14.

With this configuration, the poured concrete is discharged along the slope, and the discharge can be made even smoother.

As explained above in the examples, according to the tip structure of the tremie pipe for concrete pouring of this invention, when pouring concrete with increased viscosity, the occurrence of strength defects with the concrete can be prevented, and water pollution can also be prevented. It never comes.

[Brief explanation of the drawing]

FIG. 1 shows an embodiment of this invention, in which FIG. 1A is a perspective view and FIG. 1B is a front view. FIG. 2 is a perspective view of a second embodiment of this invention, and FIG. 3 is a front view of a third embodiment of this invention. 10...Tremy tube, 12...Collision plate, 14...
…Vent.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) Hollow cylindrical tremie pipe for pouring concrete into which high-viscosity concrete to which an admixture has been added is successively poured at a predetermined interval from above already poured concrete. A collision plate is provided at the tip of the tremie tube so as to be approximately perpendicular to its axial direction, and a discharge port for the concrete is formed by cutting the side wall of the tip of the tremie tube into semicircular shapes at multiple locations. A tremie pipe tip structure for concrete pouring, characterized by having: (2) The tip structure of a tremie pipe for concrete pouring according to claim 1, wherein the collision plate is bent to form a slope that slopes in the direction of the concrete discharge port. .