JPS6241820A - Pile of taking-out and recovery type - Google Patents

Abstract

PURPOSE:To enable pile to be easily taken out, by providing the surface of the pile, with a re-wetting lubrication layer with water absorbing polymer and re-wetting binder mixed together and dried and solidified, and by connecting a block transformed by striking the head of the pile to the lower end of the pile. CONSTITUTION:When a pile 1 is cast in a cement-milk-like cement layer 11, the water content of the cement layer 11 is absorbed by water-absorbing polymer 6 and re-wetting binder 5. Then, the water-absorbing polymer 6 is expanded to large and small balls, and the re-wetting binder 5 is gelatinized to increase the thickness of the whole re-wetting lubrication layer 2 thus producing a state that the layer 1 is removed from the pile surface. The ball-like water absorbing polymer 6 is turned into a rolling balls, state and the gelatinized re-wetting binder 5 is turned into the substitute of lubricant, and the pile 1 is struck on the head to be pressed into a block 8. By this method, the pile can be moved down, and the lubrication surface can be set to be a perfect edge surface.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a pull-out and retrieval type pile that can be easily pulled out due to the formation of rain.

Conventional technology When constructing a column retaining wall by injecting cement milk into the ground hole drilled by an earth auger, piles of type steel (f) were driven at important points in the hole containing the cement milk for reinforcement. However, when a building's ground floor room, etc. is constructed within the columnar retaining wall, the columnar retaining wall becomes obsolete.In this case, in order to recover the relatively expensive 1] type steel, Conventionally, there is a method in which grease or the like is applied to the desk surface in advance to form a beveled surface and then the piles are pulled out, but it is still difficult to pull out the piles and has the drawback of requiring a special powerful pile pulling device.

Problems to be Solved by the Invention In the present invention, when recovering a pile head driven into a cement layer, the pile head is formed with good lubrication, and the ramming of the pile head is completely formed without cutting edges. To provide a pull-out and retrieval type pile that can be easily pulled out.

Means for Solving the Problems A pull-out and retrieval type pile was constructed by connecting a deformable block to the top end of the pile by tapping the head of the pile. The water-absorbing polymer is a highly water-absorbing polymer that is insoluble in water and absorbs hundreds of times its own weight in water and swells to form a hydrogel, such as acrylic acid copolymer C cross-linked polyacrylic acid, starch polyester (acrylic acid copolymer, etc.), acrylic acid vinyl alcohol copolymer,
They are cross-linked polyethylene oxide, cross-linked carboxylmethylated cellulose sodium salt or calcium salt, etc.Rewetting binder is a substance that solidifies by drying, but becomes paste-like, mud-like, agar-like, etc. when it absorbs water.For example, These include starch sugar, polyvinyl alcohol fructose, etc. The deformable block is a material that is dented or crushed when pushed, such as hard styrofoam, rubber, cork, cans, etc.

Function As shown in FIG. 5, when the stake 1 is put into the cement layer 11 in a cement milk state, the water-absorbing polymer 6 and the rewetting binder 5 absorb the moisture of the cement 1ill, and the water-absorbing polymer 6 forms large and small balls. The rewettable binder 5 becomes a glue and increases the thickness of the entire rewettable lubricant layer 2, and solidifies with the cement layer 11 removed from the desk surface. In this case, the spherical water-absorbing polymer 6 becomes a rolling ball, and the rewetting binder 5, which has been turned into a paste, takes the place of lubricating oil, and a lubricating surface is formed between the cement layer 11 and the desk surface. thus,
When the head of the pile 1 is strongly hit, the lower end of the pile is pushed into the deformable block 8 as shown in Fig. 6, and the pile 1 moves slightly downward, completely cutting off the edge between the cement layer 11 and the desk surface. This creates an extremely smooth lubricated surface. Therefore, the pile can be easily pulled out by flying the pile head with a wire and pulling it up with a crane.

Example FIGS. 1 to 3 are explanatory diagrams of one embodiment.

1 is a type steel pile with a total length of about 5 m, a flange length of 15 cm in cross section, a web length of 30 cyn, a thickness of 0.7 h, and a weight of about 165 Kp. 2 is a rewetting lubricating layer fixed to the desk surface of the flange 3 and web 4, in which the rewetting binder 5 is 100 parts of starch sugar and the water absorbing polymer 6 is Sumikagel 5P-510 (trade name) made of acrylic acid vinyl alcohol copolymer. A thin insulating layer made of kraft paper is made by adding an appropriate amount of water to 30 parts of kraft paper (manufactured by Kagaku Co., Ltd.), adding an appropriate amount of water, kneading it until it becomes a paste, and pasting this paste on a desk surface.

8 is a hard polystyrene foam block formed into an I-shaped material larger than the pile 1, and has an I-shaped groove 9 recessed in the upper surface, and when the lower end of the pile is fitted into this I-shaped groove 9, the block 8 is inserted into the pile. connected to l.

As shown in Fig. 4, the pile 1 described above is constructed such that the continuous row holes l for the columnar earth retaining wall formed by the earth auger form a lubricating surface, and 10 days after the seven-layer layer 11 has solidified, the head of the pile l is The pile is lowered slightly by hitting it with a Monken equipped with an earth auger, and the lower end of the pile is pushed into the ■-shaped groove 9 of the block by a depth of 1. As a result, the swollen lubricant layer shrinks into a skeleton shape and forms a cement layer. When a gap remained between No. 11 and the desk surface, the pile was easily pulled out by hitting the pile head in the same manner to complete the edge cutting surface and pulling up the pile. In the case of pulling these out, it is possible to prepare the usual pile by adding a slightly large traction force to the weight of the pile, and to attach it to the desk surface when using it.

The effect of the invention is that it swells into a spherical shape and becomes a trochanter, and the rewettable binder turns into a paste, becomes slurry, and becomes a lubricating oil, and a spherical lubricating surface is formed between the solidified cement layer and the desk surface. Since the deformable block is located at the lower end of the pile, the pile can be moved slightly downward by the hammering, so the lubricated surface can be made into a perfect edge cutting surface, and therefore the pile can be easily pulled out from the cement layer. Can be done.

[Brief explanation of the drawing]

Fig. 1 is a front view of an embodiment of the present invention, Fig. 2 is an exploded perspective view of the main parts of the above, Fig. 3 is an enlarged sectional view of the rewetting lubricant layer of the above, and Fig. 4 is the state of use of the same. FIG. 5 is an enlarged sectional view of the same layer showing the effect of the rewetting lubricant layer, and FIG. 6 is a front sectional view showing the entire effect of the pile upper end block. In the figure, 1...Pile, 2...Rewetting lubricant layer, 5...Rewetting binder, 6...Water absorbing polymer, 8...Block, 9...■ shaped groove, ll...・Cement layer.

Claims (1)

[Claims] A pull-out and retrievable pile that has a rewettable lubricant layer on the pile surface made by kneading a water-absorbing polymer and a rewettable binder and solidifies it by drying, and a block that can be deformed by hammering is connected to the lower end of the pile.