JPS6250517A - Method and apparatus for construction of ready-made hollow pile - Google Patents

Abstract

PURPOSE:To raise the efficiency of operations by a method in which a hollow pile having upper and lower openings is inserted into a prebored pit filled with a hardening liquid, the liquid in the pile head is removed out by jet water, and anchoring reinforcing bars are inserted into and fixed to the pile head. CONSTITUTION:A prebored hole A is excavated in the ground, and a hardening liquid is packed into the hole A. A ready-made hollow pile B whose upper and lower ends are opened is tipped with a cap 1 and inserted into the hole A. A kelly bar 2 is turned to rotate the pile B, thus penetrating to a level of 1m from the bottom the hole A. While the liquid is unhardened, the liquid in the hollow pile head is removed out to a given depth by jet water. Anchoring reinforcing bars 3 are inserted into the pile head, and concrete, etc., is filled into the pile head to fix the lower parts of the bars 3 to the pile B.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for constructing ready-made hollow piles and an apparatus used for the construction, and in particular to insertion into a pre-bored hole;
The present invention relates to a method and device for facilitating the arrangement of anchor reinforcing bars.

Conventional technology In the ready-made pile embedding method, an open-ended ready-made pile is inserted into a pre-bored hole filled with a hardening injection liquid, and an anchor reinforcing bar or reinforcing bar cage is inserted into the opening at the upper end to install it, and the anchor reinforcing bar is attached to the footing concrete. Methods have been implemented to establish this within the country.

Problems to be Solved by the Invention In the method described above, the hollow part of the ready-made pile is filled with the hardening injection liquid and hardened. Therefore, in order to insert the anchor reinforcing bars into the pile head, it is necessary to remove the hardened injection fluid by grinding, which requires a great deal of labor.

Means for Solving the Problems The configuration of the present invention is to insert an open-end pile into a pre-bored hole filled with a hardening injection liquid such as cement milk, and to insert the open end pile into a pre-bored hole filled with a hardening injection liquid such as cement milk. In this method, the hardening liquid in the head of the ready-made hollow pile is removed to the required depth by jetting water, and then anchor reinforcing bars are inserted into the head and fixed using concrete, etc. In order to carry out pile suspension, a metal fitting called a rotary cap consisting of a cylindrical part that fits into the pile head and a shaft protruding above the cylindrical part is installed from the lower end of the shaft into the cylindrical part. A device equipped with a spray nozzle is used to spray pressurized water from the spray nozzle to wash away the uncured hardening liquid in the pile head to the required depth and remove it.

EXAMPLE First, a pre-boring hole A is excavated using an excavator having an enlarged pit in the ground. At this time, cement milk is injected into the pre-boring hole A through the shaft of the excavator, or the excavator is rotated up and down while injecting cement milk to mix and stir the earth and sand to form fill cement. is filled with curable injection liquid.

Next, a ready-made hollow pile B with a diameter slightly smaller than that of the pre-bored hole A and open at the upper and lower ends is inserted into the pre-bored hole A. At this time, a removable cap 1 is attached to the pile cap, and by suspending this cap 1, the pile B is erected and initially sinks due to its own weight, but with a hardening injection liquid having a large specific gravity, the hole A Pile B is rotated by rotating Kelly bar 2, which is connected to cap 1, and the pile B is raised to a height of 1 m from the bottom of hole A by cutting the friction with the hardening injection liquid. Insert. As a result, the gap between the hole A and the pile B and the hollow hole of the pile B are filled up to the head with the curable injection liquid. Next, while the curable injection liquid is still uncured, the curable injection liquid inside the pile head is removed by washing it away with jet water to a required depth, and then an anchor is formed into a desired shape such as a brush shape within the pile head. Insert the reinforcing bar 3, fill the head with concrete, etc., and fix the lower part of the anchor reinforcing bar 3 to the pile B. Note that the upper part of the anchor reinforcing bar 3 is buried in the footing C of the foundation.

Cap 1 used as a device for carrying out the above method
The shaft 5 and the cylindrical portion 4 are connected to a cylindrical portion 4 that fits into the head of the pile B, and a kelly bar 2 that protrudes above the cylindrical portion 4.
and the shaft 5 and the arm rod 6 arranged in a radial manner to connect the shaft 5 with the shaft 5.
It consists of an injection nozzle 7 which is detachable from the cylindrical part 4 and has a required number of injection holes protruding into the cylindrical part 4.

High pressure water is sent to this injection nozzle 7 from a pump 8 via a hose 9. In addition, when rotating the injection nozzle 7'' straddle cap 1, a swivel mechanism is provided at the connecting part between the shaft 5 and the hose 9.
As the attaching/detaching mechanism, a conventionally known structure can be adopted in which an inverted cut is formed in the lower end of the cylindrical body part and a protrusion provided on the pile head is engaged with this cut. For example, there is a structure shown in Japanese Patent Publication No. 56-6451.

Effects of the Invention This invention has the above-mentioned configuration, and by washing away the hardening injection liquid that has filled the vicinity of the pile head in the hollow part of the pile with jet water, folding work inside the hollow part can be omitted, and anchor reinforcing bars can be inserted into the head of the pile. This makes it easy and reliable to insert and fill with high quality mortar.

In addition, by attaching the water removal spray nozzle for the above work to the cap used for pile erection and rotational insertion, water can be sprayed immediately after pile insertion, improving work efficiency and equipment. It can be provided at low cost.

[Brief explanation of the drawing]

1, 2, 3 and 4 are longitudinal sectional views showing the construction process, and FIGS. 5 and 6 are longitudinal sectional views and bottom views of the equipment used in the construction. A... Pre-boring hole, B... Pile C... Footing, 1... Cap 2... Kelly bar 13... Anchor reinforcing bar 4... Cylindrical part, 5... Shaft, 6... Arm bar 7... Injection nozzle, 8...Pump, 9...Hose No. 3, No. 4, No. 5L! ! 'J6 figure

Claims (2)

[Claims] (1) Insert a ready-made hollow pile with open top and bottom ends into a pre-bored hole filled with a curable injection liquid, and while the curable injection liquid has not yet hardened, apply the curable injection liquid inside the head of the ready-made hollow pile. 1. A method for constructing a ready-made hollow pile, which comprises removing the head with water spray, and then inserting and fixing an anchor reinforcing bar into the head. (2) A cylindrical part that fits into the pile head of a ready-made hollow pile, a shaft that projects above the cylindrical part, an arm rod that connects the cylindrical part and the shaft, and a shaft that protrudes into the cylindrical part from the lower end of the shaft. A construction device for ready-made hollow piles, characterized by comprising an injection nozzle.