JP2006193895A - Fluidized soil and fluidization treatment method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain fluidized soil which enables the recycle of concrete residue, the compressive strength of which can be increased, and which can reduce cracks and facilitate compaction and smoothing work, and a fluidization treatment method. <P>SOLUTION: In the fluidization treatment method wherein water or slurry and a solidification material are added to soil generated in construction, mixed and fluidized, and transported and placed in the state of maintaining the fluidity of them, the water or the slurry, the solidification material, and demolition residue aggregate in a wet state are mixed into the soil generated in the construction are mixed into the soil, so that the compressive strength of the fluidized soil can be increased. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fluidized soil and a fluidized treatment method.

  Most of the soil generated at the construction site has been landfilled in the sea or fields without being reused. As a method for reusing such generated soil, there is a fluidization method.

  This fluidization treatment method is a method of transporting and placing in a state where the fluidity is maintained by fluidizing the construction generated soil by adding and kneading water or mud containing a large amount of water and a solidifying material. .

  The fluidization treatment method does not contain organic substances and can regenerate all soils other than humus, and also exhibits mud properties during production and exhibits a predetermined strength with a solidifying material after a certain period of time. Because of its good fluidity, it can reliably fill even complex cross-sections and is self-hardening, so it can be backfilled without compaction. Because of its high power, it does not suffer from erosion such as groundwater, and hardly undergoes volume shrinkage during solidification. Therefore, when it is used for backfilling and backfilling, it can be restored without temporary restoration.

  Furthermore, by using muddy water with adjusted density, flow value, sand content, etc., it is possible to maintain a certain quality by adjusting the composition even if the type of soil changes, and its strength after solidification It does not liquefy even during an earthquake.

By the way, along with the construction soil, there is so-called concrete debris as demolition concrete as construction waste. This concrete glass is generated in large quantities at the time of demolition of a concrete structure. However, as described in the following patent document for reusing this, the concrete glass is conventionally mixed with the target mud and adjusted to a predetermined quality. There is one that makes muddy water and uses it to solidify muddy soil.
JP-A-9-125395 JP 2003-26162 A

  Patent Document 1 provides a mud treatment technology that can effectively use soil and sand mixed with solidification material, concrete glass, and the like, and obtain stable mud with uniform specific gravity and grain distribution. A slurry-like material in which water is added to solids and stabilizing liquid mixed with solidifying material and concrete glass or the like is circulated in the circulation path to remove aggregates such as gravel, and through the sampling tube, uniform specific gravity and Collect adjusted mud with grain distribution.

  According to Patent Document 2, the adjusted mud water is a regenerated fine powder obtained by heating and grinding water and concrete waste, and the water mass (W) is 70% <W with respect to the regenerated fine powder mass (B). The content is to be blended so that <B <120%.

  The prior arts disclosed in Patent Document 1 and Patent Document 2 can recycle concrete glass, and can obtain a predetermined strength without reducing or using a conventional solidified material. The compressive strength cannot be increased and the strength problem remains.

  In addition, when the concrete glass is dried, if it is added to the soil generated by adding water or muddy water and solidifying material to the construction generated soil and fluidized, it will not be sufficiently kneaded on-site, and pumping, Material separation at the time of placing occurs, and a flow and slump suitable for construction cannot be obtained.

  The purpose of the present invention is to solve the disadvantages of the conventional example, and it is possible to recycle the concrete glass and increase the compressive strength of the fluidized soil. An object of the present invention is to provide a fluidized soil and a fluidized treatment method capable of reducing volume shrinkage and reducing cracks and facilitating compaction and leveling operations.

  The present invention achieves the above-mentioned object, and the invention according to claim 1 is characterized in that water or muddy water and a solidifying material are added to the construction-generated soil, kneaded and fluidized, and transported and hammered in a state in which the fluidity is maintained. In the fluidization treated soil used in the fluidization treatment method of setting, the gist of the present invention is that the dismantled aggregate in a wet state is mixed into the fluidized treatment soil.

  The gist of the invention according to claim 2 is to set the mixing rate of the disassembled glass aggregate to 50% or less.

  The gist of the invention according to claim 3 is that the disassembled glass aggregate has a particle size set to 40 mm or less.

  The invention according to claim 4 is a fluidization treatment method in which water or muddy water and a solidifying material are added and kneaded and fluidized as a construction method, and transported and placed in a state in which the fluidity is maintained. The gist is to mix water or muddy water, a solidified material, and a disassembled glass aggregate in a wet state into the construction-generated soil.

  According to the first and fourth aspects of the present invention, not only industrial waste can be reduced by adding demolition glass aggregate in addition to muddy water and solidified material to construction generated soil, but also fluidized treated soil. The compressive strength of the resin can be increased, cracking can be reduced, and compaction and leveling can be facilitated.

  In addition, by using a dismantled aggregate in a wet state, when it is mixed with construction generated soil and water or muddy water, and solidified material, it does not absorb water. A predetermined strength can be secured without changing the cement ratio.

  According to the second aspect of the present invention, in addition to the above action, by setting the mixing rate of the dismantled glass aggregate to 50% or less, without reducing the workability and compressive strength of the fluidized soil, Reduce industrial waste.

  According to the third aspect of the present invention, in addition to the above-described function, by setting the particle size of the disassembled glass aggregate to 40 mm or less, pulverization at the site and kneading into the construction generated soil are possible, and fluidization is achieved. Material separation at the time of pumping and placing the treated soil can be avoided, and the workability can be improved.

  As described above, the fluidized soil and the fluidized method according to the present invention can be used to recycle the concrete demolition glass aggregate by mixing the concrete glass into the fluidized soil. The compressive strength of the soil can be increased, and the gap ratio can be reduced by mixing demolition aggregate, which reduces the volume shrinkage and reduces cracks after placement, compaction and leveling work. It can also be facilitated.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The fluidized soil of the present invention is used in a fluidized construction method in which water or muddy water and a solidifying material are added to a construction generated soil, kneaded and fluidized, and transported and placed while maintaining the fluidity. However, in addition to the water or muddy water and the solidified material, a disassembled glass aggregate such as concrete glass generated inside or outside the site is mixed as a material mixed in the construction generated soil.

  The condition of the dismantled aggregate is that the particle size is 40 mm or less, the wet state is not dry, and the mixing rate is 50% or less. Here, the wet state means that moisture has adhered to the surface of the disassembled glass aggregate, and the water content is equal to the amount of water absorbed + the surface water amount. It is in a state of sticking.

The reason for using disassembled glass aggregate with a particle size of 40 mm or less is
(1) Can be kneaded into construction generated soil on site. (Mixing and stirring is performed by a special agitator vehicle.)
(2) It is possible to avoid material separation when the fluidized soil is pumped and placed. (Place by bucket or pump.)
(3) A flow slump suitable for construction can be obtained.
(4) The test piece size in strength management is 100 mm × 200 mm.
(5) Pulverization by a pulverizer on site is relatively easy.
Etc.

In addition, the reason for using a wet state instead of a dry state is
(I) When a dry thing is used, the workability of said (1)-(3) cannot be satisfied. In order to satisfy the workability, it is sufficient to keep the amount of debris aggregate mixed even if it is in a dry state. However, this is the intended purpose of reducing industrial waste. Cannot be achieved.
(Ii) When a dry material is used, the water / cement ratio of the fluidized soil changes due to water absorption, which may reduce the quality of the fluidized soil produced at a predetermined ratio.

The reason why the mixing rate is 50% or less is as follows.
(A) If it exceeds 50%, the workability of the above (1) to (3) deteriorates rapidly, and the construction becomes almost impossible.
(B) When the mixing rate is much less than 50%, only a very small amount of aggregate can be used, and the intended purpose of reducing industrial waste cannot be achieved.
(C) If it is 50% or more, the compressive strength of the fluidized soil will decrease.

  Next, test results that serve as a basis for determining the above conditions are shown.

  FIG. 1 is a graph showing the relationship between the mixing rate of dismantled glass aggregate and the flow value. When the disassembled glass aggregate is in an absolutely dry state and the mixing rate is 50%, the flow value required for kneading and construction is not about 120 mm. However, in the wet state, the flow value = 120 mm was almost satisfied even when the mixing rate was 50%.

  FIG. 2 is a graph showing the relationship between the mixing rate and slump (concrete subsidence). It can be seen that when the mixing rate of disassembled glass aggregate exceeds 50%, the workability decreases rapidly. It can be seen that kneading and construction are impossible with such a self-supporting material at a mixing rate of 50% or more, and the mixing rate of disassembled glass aggregate is an important index for construction.

Table 1 below shows the slump test results.

  FIG. 3 is a graph showing the relationship between the mixing rate of disassembled glass aggregate and the uniaxial compressive strength. It can be seen that a mixing rate of about 50% is optimal in terms of strength.

  Further, the blending strength is determined by the water / cement ratio-strength relationship or the unit cement amount-strength relationship, and the blending strength can be set in the same manner as concrete.

  FIG. 4 is a graph showing the relationship between the water / cement ratio and the uniaxial compressive strength, showing properties similar to those of concrete, and it can be seen that the relational expression is established when the mixing ratio is approximately 50%.

  FIG. 5 is a graph showing the relationship between the mud specific gravity and the uniaxial compressive strength, and it can be seen that the compressive strength of the fluidized soil mixed with dismantled glass aggregate is closely related to the water / cement ratio or the mud specific gravity.

  In this way, the dismantled aggregate in a wet state with a particle size of 40 mm or less can be pulverized on site and kneaded into construction generated soil, and this disassembled aggregate is mixed into construction generated soil at a mixing rate of 50% or less. The fluidized soil thus obtained is easy to compact and level, and after placing, the compressive strength increases and cracks are less likely to occur.

It is a graph which shows the relationship between the mixing rate of the demolition glass aggregate of the fluidization processing soil of this invention, and a flow value. It is a graph which shows the relationship between the mixing rate of the dismantling glass aggregate of the fluidization processing soil of this invention, and workability (slump). It is a graph which shows the relationship between the mixing rate and the uniaxial compressive strength of the demolition glass aggregate of the fluidization processing soil of this invention. It is a graph which shows the relationship between the water cement ratio and uniaxial compressive strength of the fluidized soil of this invention. It is a graph which shows the relationship between the mud specific gravity and uniaxial compressive strength of the fluidization processing soil of this invention.

Claims (4)

  In the fluidized soil used in the fluidization treatment method, which is transported and placed in a state where water or mud water and a solidifying material are added to the construction generated soil, kneaded and fluidized, and the fluidity is maintained. Fluidized treated soil, characterized in that dismantled glass aggregate in a wet state is mixed into the treated soil.   The fluidized soil according to claim 1, wherein the dismantled aggregate is set to a mixing rate of 50% or less.   The fluidized soil according to claim 1 or 2, wherein the disassembled glass aggregate has a particle size set to 40 mm or less.   In the fluidization treatment method where water or muddy water and solidification material are added to the construction generated soil, kneaded and fluidized, and transported and placed while maintaining its fluidity, the construction generated soil is solidified with water or muddy water. A fluidization treatment method characterized by mixing debris aggregate in a wet state with the material.

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