JPS6140919A - Formation of pile solidified on site - Google Patents

Abstract

PURPOSE:To easily form a pile by a method in which a soil solidifying agent is charged into a pile, mixed with excavated soil in excavation work by a drill, and discharged until a target depth is reached, and the soil and solidifying agent so discharged are returned to the pit. CONSTITUTION:The screw 3 of a drill is lowered while being turned toward the direction of arrow X to form a pit 2 in the ground 1, and a ground solidifying agent 4 is charged into the pit 2. When the excavation is proceeded to the depth IIby lowering the screw 3 into the pit 2 while penetrating it with normal turning, the agent 4 charged previously is mixed with excavated soil 5 and discharged to the outside of the pit 2 in order. The screw 3 is pulled up, the agent 4 is charged into the pit 2, and the screw 3 is lowered in the pit 2 while being turned normally to excavate to the depth III. While the screw 3 is pulled up by turning it reversely, the mixture of the soil 5 and the agent 4 discharged to the outside of the pit 2 is returned to the pit 2 in order.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is mainly applied to the construction of on-site soil consolidation piles, which are applied to the construction of pile-shaped hardened bodies on-site in shallow or intermediate ground. It is about the method.

[Prior art] The conventional method for creating on-site soil consolidation piles is to forcibly inject slurry-like #ml material into the soil using a special feeding device, and then pour the injected portion into the soil using a mixing blade or There are some that use a screw to stir (for example, Japanese Patent Publication No. 59-IS049 ``Method of Forming Columns in the Ground'').

In addition, as another method, there is a method in which powdered ground solidifying material is transported by air and mixed with special blades (for example, the development of powder injection stirring method, Shohei Senda, Yoshiaki Murao , “Bridge J1981°5, P27-33).

[Problems to be Solved by the Invention] However, when creating land using the conventional method, it is necessary to install a dedicated solidification material supply device, and a high-output mixing machine that drives mixing blades is indispensable. , there is a problem that the equipment becomes large-scale. In addition, when using a slurry-like ground solidifying material, the method involves mixing water, which is disadvantageous to the strength development of the hardened material, so it is not only difficult to ensure high strength, but also to obtain the same strength. However, there is also the problem that a larger amount of solidified material is required than when using powdered material.

The present invention attempts to solve these problems all at once.

[Means for Solving the Problems] In order to achieve the above object, the present invention has the following (L):
The method is characterized in that the step (e) is added to the steps (b), (c), and (d), if necessary, to create a pile-like hardened body on the site.

(a) A hole is drilled in the surface layer of the ground using a hole drilling machine having an agitating and ejecting unit, while a predetermined amount of soil solidification material is injected to a depth at which the hole wall does not collapse.

(b) After putting the soil solidification material into the hole, insert the drilling part of the hole drill into the hole and drill to a specific depth, and keep the hole drill at the specific digging position for the required time. The excavated soil and solidified material are stirred and discharged while maintaining the rotating state.
Thereafter, the hole is deepened by performing a series of operations such as removing the hole drill from the hole once or multiple times.

(c) Inject soil solidification material into the hole extracted by the drilling machine,
Insert the drilling part of the drilling machine into the hole again and drill to the target depth.

(d) When the target depth is reached, after maintaining the normal rotation of the drilling machine for the required time, the drilling machine is reversed, and the discharged soil and solidification material are returned to the hole and compacted while The hole drill is pulled out of the hole.

(e) Hy when it is necessary to reinforce the pile-shaped hardened body.
! ! , press-fit reinforcing materials such as steel, engineering steel, rail steel pipes, etc. into predetermined positions.

[Function] Through the above-mentioned step (a), a ground solidifying material is mixed into the discharged soil, and an opening hole for introducing the ground solidifying material is formed.

Then, in step (b), the hole is deepened,
At that time, the work of mixing ground solidification material on the site,
Reinforcement of the hole walls takes place at the same time. In other words, soil solidification material is poured into the hole, the hole is dug to a specific depth, and then
If the drilling machine is kept in normal rotation for the required time, the
The soil solidification material that had been put into the hole is stirred and mixed before being discharged out of the hole. Further, at this time, a portion of the soil solidification material is attached to the hole wall, so that the hole wall is reinforced. Therefore, even if the hole drilling machine is pulled up to introduce new soil solidification material into the hole, the hole wall is prevented from collapsing. Then, in step (c), the hole is reinforced and dug to the target depth, and in step (d), the discharged soil is remixed by reversing the drilling machine and backfilled into the hole while being compacted. As mentioned above, this discharged soil is mixed with a soil solidifying agent. Therefore, over time, the soil solidification material causes a water utilization reaction and fixes the soil particles, forming a pile-like hardened body in the backfill area. Furthermore, in the step (e), the bending and shearing strength of the hardened pile body is increased as required, and it becomes possible to withstand larger external forces.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings. First, as shown in FIG. Hole 2 is drilled to a depth that will prevent wall 2a from collapsing. This drilling work requires a general-purpose screw drilling machine.

That is, the screw 3, which is the hole-drilling part of the hole-drilling machine, is rotated normally in the direction of the arrow X and lowered one by one in the axial direction at a predetermined speed to form the hole 2 in the ground 1. At this time, a predetermined amount (for example, 200 kg) of ground solidifying material per 1 m1 of discharged soil is uniformly poured into the hole being drilled. A predetermined amount of ilI! is added to the soil discharged by this method. ! A plate hardening agent can be mixed.

Next, as shown in FIG. 2, a ground solidifying material 4 is poured into the hole 2. The ground solidifying material 4 is a solidifying material whose main materials are plaster, blast furnace slag, and ordinary Portland cement, with the addition of a halogen compound or sulfate as a hardening accelerator as needed and mixing well.
It is commercially available as SC (trade name; manufactured by Osaka Cement Co., Ltd.). That is, this solidification material 4 is made by changing the mixing ratio of the main materials, plaster, blast furnace slag, ordinary portland cement, and cement, to 15 to 60 (wt%) of plaster, 20 to 60 (wt%) of blast furnace slag, and 20 to 60 (wt%) of ordinary portland cement. 50 (wt%), and their specific surface area is 4.
Either grind and blend to a concentration of 500 cmz/g or less, or
Alternatively, it is prepared by adding 5 (wt%) or less of a curing accelerator to these materials and pulverizing and blending them, and has water absorption, swelling properties, and hydraulic properties. The amount of the soil solidifying material 4 to be added is a ratio of the set addition amount (Kg/m3) to the amount of soil in the undischarged part, that is, the part from depth 1 to depth 2.

In this way, a third
As shown in the figure, insert the screw 3 of the hole drilling machine again and lower it while rotating normally in the direction of the arrow
Excavate to L-5m).

Then, when the depth H is reached, the descent of the screw 3 is stopped, but the forward rotation state of the screw 3 is maintained as it is. At this time, the previously introduced solidification material 4 and the excavated soil 5 are further mixed and are sequentially discharged out of the hole 2. Then, when ±5 is no longer discharged, the screw 3 is pulled out from the hole 2. In addition, screw 3
When excavating the solidified material 4, and when the screw 3 is rotated normally at a certain position to mix and discharge the solidified material 4, a part of the solidified material 4 is stuck to the hole wall 2a. Therefore, the hole wall 2a is reinforced, and even if the screw 3 is pulled out of the hole 2, the hole wall 2a will not collapse.

Next, as shown in FIG. 4, a ground solidifying material 4 similar to that described above is poured into the hole 2 that has been dug down to a depth of {circle around (2)}. In this case, the input amount is the set addition amount (Kg/m1) for the soil volume from depth ■ to depth positive (for example, 200Kg/m1).
m') (7) The amount is a proportion.

In this way, the fifth
As shown in the figure, insert the screw 3 of the hole drilling machine again and lower it while rotating normally in the direction of the arrow X to a depth of m (for example, G
Excavate to L-7m).

Then, when the depth ■ has been reached, the descent of the screw 3 is stopped, but the forward rotation state of the screw 3 is maintained as it is. At this time, the ground solidifying material 4 introduced at the stage shown in Fig. 4 and the excavated ±5 are further mixed, and
It is sequentially discharged out of the hole 2.

In this way, the time required (about 1 to 3 minutes) is to screw 3 screws.
After the screw 3 is rotated in the normal direction, the screw 3 is rotated in the reverse direction in the direction of arrow Y as shown in FIG. 6, and the mixture of soil 5 and soil solidification material 4 discharged from the hole 2 is sequentially returned. At that time, the screw 3 is pulled up at a slow speed. As a result, ±5 and ground solidifying material 4 are returned to the hole 2.
are further mixed and compacted. The degree of compaction can be controlled by the load of the screw drive device, etc.

Then, as shown in FIG. 7, when the screw 3 is completely pulled up from the hole 2, the hole 2 is completely filled with the mixture of soil 5 and soil solidifying material 4. As shown in FIG. 8, H-shaped steel 7, ■-shaped steel, rail steel pipes, etc. are press-fitted into the piles that need to be reinforced at predetermined positions. However, if this is left as it is, the ground solidifying material 4 reacts with time and exhibits a hardening effect, and a pile-shaped hardened body 6 is created. The self-supporting depth of the hole wall and the excavation depth for each construction stage will be determined through preliminary test excavation.

In addition, in the following examples, J1! into the hole! ! Although the case has been described in which a series of operations is performed in one go: charging of solidification material → excavation with a set of screw augers → agitation and soil removal by forward rotation of the screw → pulling the screw out of the hole, the present invention does not necessarily require that the series of operations be performed once. It is not limited to such things. That is, if the target depth is relatively deep, the series of operations described above may be repeated multiple times.

The soil solidifying material is of course not limited to those mentioned above; for example, various materials such as ordinary Portland cement and blast furnace cement can be used.

[Effects of the Invention] Since the present invention has the above configuration, the following effects can be obtained.

First, it is possible to supply the solidifying material into the ground by simply inserting it into the hole, so a feeding device is required to forcefully inject the solidifying material into the ground by applying pressure. It is unnecessary and there is no need to add water, which is disadvantageous to the development of strength, and to make the solidifying material into a slurry that tends to flow out.

In addition, if a soil solidifying material is poured into the hole and the hole is excavated with a hole drilling machine, the solidifying material will be stuck to the hole wall during excavation, so the hole drilling machine of the hole drilling machine will be used to introduce the new solidifying material. Even if it is temporarily pulled out of the hole, the hole wall will not collapse.

In addition, according to the above-mentioned procedure, it is possible to stir and mix the solidified material supplied and on-site using only a general-purpose hole drilling machine, so it is possible to stir and mix the solidified material supplied on-site using only a general-purpose hole drilling machine. does not require.

Therefore, according to the present invention, large-scale special equipment is installed on-site to prepare a hardened material in the form of a hardened stone for gobo. It can be reliably created without any damage. In addition, in the embodiment, the case where a screw set with one hole is used is described.Force≦If, there is a hole drilling machine that performs the same or better role. You can expect the same or better effect.

[Brief explanation of drawings]

FIGS. 1 to 8 are process explanatory diagrams showing one embodiment of the present invention,
FIG. 9 is a view taken along arrow A in FIG. 1... Ground 2... Hole 3 @ Command excavation part (screw) 4... Ground solidification material 51, soil 6... Hardened body 7... Reinforcement steel material

Claims (1)

[Claims] The following steps (a), (b), (c), and (d) are performed in sequence, and if necessary, the step (e) is added to form a hardened pile in the ground. A method for creating an on-site soil solidification pile, which is characterized by creating a solidified pile. (a) A hole is drilled in the surface layer of the ground using a hole drilling machine with stirring and discharging functions, while introducing a soil solidifying material to a depth that does not cause the hole wall to collapse. (b) After putting the soil solidification material into the hole, insert the drilling part of the hole drill into the hole and drill to a specific depth, and keep the hole drill at the specific digging position for the required time. The excavated soil and solidified material are stirred and discharged while maintaining the rotating state.
Thereafter, the hole is deepened by performing a series of operations such as removing the hole drill from the hole once or multiple times. (c) Inject soil solidification material into the hole extracted by the drilling machine,
Insert the drilling part of the drilling machine into the hole again and drill to the target depth. (d) At the stage when the target depth is reached, after maintaining the normal rotation state of the drilling machine for the required time, the drilling machine is reversed and the discharged soil and solidified material are returned to the hole while drilling the hole. Pull the machine out of the hole. (e) When it is necessary to reinforce the pile-shaped hardened body, reinforcing materials such as H-shaped steel, I-shaped steel, rails, steel pipes, etc. are press-fitted into predetermined positions.