JPS62160316A - Burying work of pile - Google Patents

Abstract

PURPOSE:To obtain high bearing capacity of the conventional cement milk construction work by a method in which slime in a pit is removed out, concrete for foot protection is placed, and a pile is penetrated. CONSTITUTION:A pit A is excavated in the ground with an excavator 1 by a mud water construction method, and a slime treating agent composed of water glass or cement milk is injected into slime S with stirring to softly harden it. Cement milk is then injected below into the soft slime solid S' and the excavator 1 is pulled up under a condition that the soft slime solid S' is placed on the excavating head 2. Concrete 3 is then placed into the pit B and a custom- made pile is penetrated by fixing its tip in the concrete. The slime can thus be exactly removed out, and a sufficient bearing capacity can be provided to the in-situ concrete pile. The bearing capacity obtained is higher than that by the conventional cement-milk construction work.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a pile embedding method in which foot protection concrete is poured into an excavated hole and piles are inserted into the concrete.

[Prior art and problems to be solved by the invention] Currently, various pre-poling methods have been developed and implemented as low-pollution construction methods, in which cement milk is injected into the borehole and ready-made piles are erected, but none of them are percussive methods. As such, the bearing capacity cannot match the bearing capacity of the pile, and only a relatively small bearing capacity is recognized.

The applicant has proposed a pre-poling method in which ready-mixed concrete is used for the enlarged portion at the tip (see Japanese Patent Application Laid-Open No. 1983-1983).

By the way, when an auger is used as an excavator and a hole is drilled by the muddy water method, slime often forms at the bottom of the hole.

This invention was developed in order to treat the slime, cast foot protection concrete at the bottom, and insert ready-made piles into the concrete, thereby achieving a tip bearing capacity coefficient comparable to that of the impact method.

[Means for solving problems]

This invention uses the muddy water method to drill a hole in the ground with an excavator, then injects and stirs a slime treatment agent made of water glass or cement milk into the slime that collects at the bottom of the hole, and then softens the slime. Cement milk is pressed into the bottom of the hole, and the excavator is pulled up with the softened slime placed on the excavation head. Next, concrete is poured into the hole, and a ready-made mold is placed so that the tip of the excavator is fixed in the concrete. This is a method of erecting piles.

〔Example〕

The construction outline of this construction method is as shown in Figs. 1 to 6, which show an example in which the tip is enlarged.

First, using the muddy water method, a hole AL is drilled in the ground with the excavator 1 (see Figure 1), then an enlarged hole B is excavated with the enlarger head 2 (see Figure 2), and then the bottom of the enlarged hole B is drilled. (See Figure 3) Next, cement milk is injected into the underside of the softened slime, and then concrete 3 is poured through the rond of excavator 1 (See Figure 4). 1 (see Figure 5),
Next, ready-made piles C are inserted into concrete 3.

Details of slime processing are shown in FIGS. 7 to 9. When using water glass as a slime treatment agent, the main agent is industrial water glass JIS-3 standard product, and the curing agent is a solution of alkali or acid such as baking soda, phosphoric acid, dilute sulfuric acid, or cement, gypsum, calcium carbonate, etc. Use a suspension of Further, the amount of water glass and hardening agent and the slime softening strength are changed depending on the shape of the drilling bit, slime particle size distribution, water content ratio, etc. When using cement milk as a slime treatment agent, use cement, lime, or a commercially available cement-based soft soil conditioner. During construction, the water glass or cement milk is injected into the slime from the tip of the bit, and after stirring with the slime, the rotation of the rondo is stopped to soften and harden the slime.

Next, cement milk is press-fitted under the soft hardened slime S', and the rondo, that is, the excavator 1 is pulled up with the hardened slime placed on the excavation head. The lifting speed should be set to match the amount of cement milk injected.6 Next, the cement milk used in the slime treatment is changed to ready-mixed concrete, and the amount is set to a predetermined height, that is, the amount that can be filled into the enlarged hole B, and if necessary, the pile circumference is While injecting the fixative, the expanding head 2 is reduced, the excavator 1 is pulled up, and then the ready-made pile C is inserted.

The enlarged holes B can be provided at several locations not only at the bottom but also at the middle by operating the enlarging head and filled with concrete to form bulbs or knots. In addition, as a slime treatment agent, a high-grade water-based synthetic resin made of a polymer of starch and polyacrylic acid, such as Sanyo Kasei Kogyo R. Sunwet, may be used, or the above-mentioned agents may also be used.

〔Effect of the invention〕

This invention has the above-mentioned structure, and the slime at the bottom of the enlarged hole is softened, cement milk is injected into the bottom of the slime, and the slime is removed by placing it on the drilling head. Even slime removal is guaranteed. Next, concrete is filled and ready-made piles are inserted into the concrete, so the cast-in-place piles provide sufficient bearing capacity, and higher bearing capacity can be expected than in the conventional cement milk method.

[Brief explanation of drawings]

Figures 1, 2, 3, 4, 5, and 6 are cross-sectional views of the construction process of this invention, and Figures 7, 8, and 9 are explanatory diagrams of slime treatment. It is. A...Drilling, B...Enlarged hole, C...Ready-made pile, 1...Excavator, 2...Enlargement head, 3...
concrete. Figure 1 Figure 52 Figure n 3
Figure 4 Figure 5 Gai Figure 6 Figure 7 Figure 8 Figure 9

Claims (1)

[Claims] Using the mud method, a hole is drilled in the ground using an excavator, and then a slime treatment agent made of water glass or cement milk is injected into the slime that collects at the bottom of the hole and stirred to soften it.
Next, cement milk is press-fitted under the softened slime, and the excavator is pulled up with the softened slime placed on the drilling head. Then, concrete is poured into the hole, and the tip is inserted into the concrete. A pile embedding method that is characterized by erecting ready-made piles so that they are fixed.