JPS59224721A - Embedding work of concrete pile - Google Patents

Abstract

PURPOSE:To facilitate the embedding of concrete piles by a method in which an excavation shoe provided at the tip of the concrete pile is held by a chucking rod and turned integrally with the pile. CONSTITUTION:A chucking rod 8 is inserted into a concrete pile 1 having an excavation shoe 3 on its tip, and the chuck of the rod 8 is held with the coupler 4 of the shoe 3. A spiral auger is connected to the rear end of the rod 8. The rod 8 is turned by rotation of the auger, the shoe 3 and the pile 1 are concurrently turned to excavate the ground, and the pile 1 is penetrated into the hole. Concurrently, cement milk is injected from the jet nozzle 13 on the tip of the rod 8 onto the peripheral wall 15 of the pile 1 through the small holes 7 and 7' of the shoe 3, and the pile 1 is penetrated. Afterwards, the rod 8 and the shoe 3 are separated from each other, and the rod 8 is pulled out.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a concrete pile embedding method that provides strong ground support.

Conventional methods for burying concrete piles can be roughly divided into driving methods, in-situ pile methods in which concrete is cast on site, and embedding methods, each of which has advantages and disadvantages. For example, the driving method causes noise and vibration, resulting in pollution problems. In addition, the in-situ pile method requires the disposal of a large amount of soil by excavating a hole, and in soft soil or sand layers, some kind of post-treatment is required to prevent the wall of the hole from collapsing, making the construction complex. For this reason, the embedded construction method has been attracting attention recently, and for example,
Documents such as No. 6451 and Japanese Patent Publication No. 57-27255 can be found here and there. These inventions were originally a construction method in which a guide hole with approximately the same diameter as the concrete pile, etc. was excavated, and the concrete pile, etc. was rotary press-fitted or deposited under its own weight into this guide hole of approximately the same diameter, and the ground bearing capacity of the concrete pile was improved. Although it is possible to obtain a certain degree of Since it is chucked and rotated, it causes twisting in the concrete pile.
This is thought to be a factor in weakening the pile.

In view of the above, an object of the present invention is to provide an extremely simple embedding method that imparts sufficient ground support to concrete piles in the embedding method, is particularly suitable for small-diameter concrete piles, and is extremely simple. An embodiment of this will be described with reference to the drawings.

First, the apparatus used in the present invention will be explained with reference to FIGS. 1 to 3. 1 is a concrete pile having a hollow part 2, and a cylindrical excavation seam 3 is welded to the tip washer 1' of the concrete pile 1. Equally provided. This excavation 2,
-3 is a plate-shaped locking member 4 extending across the inner peripheral surface, claws 5, 5' arranged symmetrically at the lower end of the locking member 4, and a pair of spiral wings wrapped around the outer peripheral surface. 6, 6', and a plurality of small holes 7, 7' are provided on the surfaces thereof to allow passage of cement milk, water, etc. A chucking rod 8 is provided with a hollow hole 9 to be inserted into the hollow part 2 of the concrete pile 1, and is equipped with a chuck part 11 having a locking protrusion 10 at the tip. 013, which is clamped by the locking member 4 of -3, is a spout that can be opened and closed provided on the chucking rod 8. The chucking rod 8 is inserted into the concrete pile 1 which has the excavation seam 3 at the tip supported vertically by a screw (not shown), and the chuck part 11 of the chucking rod 8 is held between the locking member 4 of the excavation shoe 3. At the same time, a spiral auger (not shown) is connected to the rear end (upper end in the drawing) of the chucking rod 8.

The chucking rod 8 is then rotated by the rotation of the spiral auger. Along with this, the excavation shoe 3 and the concrete pile 1 are simultaneously rotated integrally, so that the excavation shoe 3 at the tip, that is, the pawls 5, 5' and the spiral blades 6, 6
' The state shown in Figure 4 is reached, where the ground is excavated in sequence. Then, by sequentially digging into the ground with excavation shoe 3,
The state shown in FIG. 5 is reached when the concrete piles 1 are successively press-fitted into the ground in a so-called drilled shape.

During this excavation process, cement milk is injected from the tip spout 13 of the chucking rod 8, and is sprayed onto the peripheral wall 15 of the concrete pile 1 through the small holes 7 and 7' of the excavation seam 3, and the cement milk is mixed with the excavated earth and sand on the peripheral wall. While reinforcing the peripheral wall 15 by stirring and mixing cement milk, pressurized water may be injected through the spout 13 of the chucking rod 8 to form the small hole 7. -7' to the ground at the tip of the excavation sea-3 and the surrounding wall ground, and excavation progresses while softening the ground. Even if the concrete piles 1 are press-fitted into the ground one after another in a drilled pattern and reach the predetermined position as shown in Fig. 6,
In the same manner as described above, cement milk is injected from the spout 13 of the chucking rod 8, and the excavated earth and sand around the excavation shoe 3 are stirred and mixed through the small holes 7 and 7', and the excavation shoe 3 is thereby Build root hardening bulbs surrounding them. That is, the excavation shoe 3 is left underground.Next, if the chucking rod 8 and the excavation shoe 3 are released and the chucking rod 8 is pulled out from the concrete pile 1, the concrete pile 1 will be removed.
As described in detail above, the present invention provides an excavation shoe at the tip of a concrete pile, clamps this excavation shoe with a chucking rod, and integrates it with the concrete pile. Because it is a rotating embedding method, the concrete pile penetrates well and does not require pre-excavation, which can simplify the construction method and shorten the construction period. Because it is a press-in construction method, it provides strong ground support. In addition, since this is a construction method in which a cylindrical excavation seam is widened, a hardening liquid such as cement milk surrounds this excavation seam to create a hardening bulb, which has a strong load-bearing capacity and is similar to the so-called bottom expansion method. It can be expected to be effective.

Furthermore, since the excavation method involves squirting cement milk or the like onto the surrounding wall of the concrete pile, collapse of the hole wall can be prevented. In addition, in the present invention, the cutting shoe at the tip of the concrete pile is rotated while being clamped by a chucking rod, so there is no twisting of the concrete pile, and there is no risk of damage due to torsional shearing, and no noise or vibration is generated. It has no practical effect.

[Brief explanation of the drawing]

The drawings show an example of the present invention, in which Fig. 1 is a front view showing the connection of a concrete pile and an excavation shoe, Fig. 2 is a bottom view of the same, Fig. 3 is a front view of the chucking rod, and Figs. FIG. 7 is a longitudinal sectional view showing the construction order of an example of a concrete pile according to the present invention. ■...Concrete pile, 2...Hollow part, 3...
・Drilling shoe, 4...locking member, 5, 5'...claw,
6゜6'...Spiral wing, 7,7'...Small hole, 8...
Chucking rod, 9...Hollow hole, 11...Chuck part, 13...Spout port Patent applicant Hiroshi Watanabe

Claims (1)

[Claims] A concrete pile with a cylindrical excavation shoe attached to the tip is erected, a chucking rod is inserted through the hollow part of the concrete pile, and the chucking rod is clamped by the excavation shoe at the tip of the concrete pile. At the same time,
The rotation of the auger shaft is transmitted to the excavation shoe via the chucking rod, and the rotation of this excavation shoe presses the concrete pile into the soil in a kneading shape, and at the same time, cement milk, etc. is injected from the spout at the end of the chucking rod. The circumferential wall of the concrete pile is excavated. The soil and cement milk are stirred and mixed to reinforce the circumferential wall, and concrete pipes are sequentially pressed in. When the concrete pile reaches a predetermined position, the spout at the tip of the chucking rod is inserted. It is characterized by injecting cement milk for creating hardened bulbs, then releasing the clamp between the chucking rod and the excavating shoe, and pulling out the chucking rod so that the excavating shoe remains for creating hardened bulbs. Concrete pile embedding method.