JPH07501B2 - Lightweight filler manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention provides a material, lightweight property in construction such as construction of residential land, embankment of roads, backfilling, ground subsidence countermeasure filling, and cavity filling.
The present invention relates to a method for efficiently producing a lightweight filler used in a portion where high strength and high workability are required by using soil, a solidifying material, water and bubbles formed by a foaming agent as materials. . And, the lightweight filler of the present invention has fluidity, solidification property, lightweight property and homogeneity, and is excellent in workability as well as not requiring compaction and having a narrow gap. You can get across it.

<Prior Art> Conventionally, such a filler is made of commercially available powdered clay, and in one method, water and a foaming agent are first charged into a stirrer container, and then foamed by stirring. It was produced by adding powdered clay and cement to and mixing with stirring. In another method, it is manufactured by mixing powder clay, cement and water, introducing air bubbles created by a whisk outside the stirrer into a stirrer container with a hose, and discharging and mixing a predetermined amount. Was done. A collection of fine and uniform air bubbles produced and discharged by a whisk gives a creamy appearance. Further, since this bubble film is strong, it has a characteristic that it is hard to be defoamed even when an external force is applied.

The stirrer used in these conventional manufacturing methods is
The rotation speed of the stirring shaft is relatively high, such as 100 to 350 rpm, but the rotation direction is one direction. In the case of such a one-way rotating stirrer, the flow of the mixture during stirring in the container becomes uniform in one direction in the depth direction. As a result, even if the air bubbles created by the whisk are discharged from the bottom of the container, the air bubbles are extremely light, and the lumps of creamy air bubbles co-rotate at the same speed as the mixture, There are almost no collisions and the surface floats quickly, and bubbles are less likely to be mixed and mixed. When the cream-like bubbles are floated, it becomes difficult for the bubbles to be dispersed and mixed into the lower part. The lightweight filler thus produced has a considerable variation in quality due to the non-uniformity of the dispersed state of air bubbles.

Further, in such a unidirectional rotating stirrer, it is difficult to use the natural state cohesive soil as a material as it is because of its poor peptization efficiency. In other words, in the case of a one-way rotating type agitator, co-rotation occurs in which the soil mass rotates at a rotation speed equivalent to the rotation speed of the agitation shaft, and the soil mass is fragmented in a short time due to collision with the stirring blade. Absent. Therefore, in this case, it is difficult to efficiently obtain a filling material that is sufficiently satisfactory in terms of quality and workability, such as material inseparability, homogeneity, strength development, and pumpability.

<Problems to be Solved by the Invention> In view of the above circumstances, the present inventors have made it possible to use cohesive soil in a natural state as a material, efficiently and uniformly mix air bubbles, and provide a high-quality lightweight filler. For the purpose of efficiently producing, the present invention was eagerly studied. Considering the use of natural cohesive soil, it has an advantage over powdered clay that lightweight filler with better properties can be obtained at a lower cost due to its high water retention and reactivity with solidifying material. It depends on the sex.

<Means for solving the problem> As a result of the study, by mixing the materials by using a stirring device in which a special stirring device is combined with a special bubble discharging device,
The inventors have found that the above problems can be solved, and have achieved the present invention based on such findings.

That is, the present invention, by using a stirrer in which a reciprocating rotary stirrer and a bubble discharge device are combined, by stirring and mixing a material consisting of soil, a solidifying material, water and bubbles made of a foaming agent, It is a method for producing a lightweight filler, which is characterized by efficiently obtaining a light material having a high degree of homogeneity, fluidity and solidification.

For example, a method of manufacturing a lightweight filler with a reciprocating rotary agitator in which a circular bubble discharge tube is arranged at the bottom of a container.First, by mixing and stirring soil, water, and a solidifying material, a highly homogeneous and dispersed mixture is created. Further, it is possible to quickly and uniformly disperse and mix air bubbles, and produce and supply a high-quality lightweight filler in a short time.

In the present invention, the reciprocating rotary stirrer has a stirring blade whose cross-sectional shape is preferably triangular, and the stirring shaft does not rotate in one direction, but is inverted every 1/4 rotation, for example, to improve stirring efficiency. Device. Due to the reciprocating rotation of the reciprocating rotary stirrer with a triangular cross-section stirring blade, the mixture causes convection in the depth direction instead of a uniform flow in the depth direction. Turbulence is also generated by turning off. The stirring blade, the soil lump, and the lumpy bubble repeatedly collide with each other by stirring, and the action of the turbulent flow also overlaps with each other, and the subdivision and miniaturization progress.

<Operation> When the bubbles created by the foaming agent are dispersed from the numerous discharge holes of the circular bubble discharge pipe at the bottom of the stirrer container in the agitated state and a predetermined amount is discharged, the bubbles form a lump and float at once. There is no end. Bubbles riding on the convection of the mixture are subdivided by repeated collisions with the agitating blades, and due to the action of turbulence, further miniaturization progresses and become independent bubbles that are in a stable state and evenly exist in the mixture. To do. Thus, a lightweight filler having stable closed cells can be efficiently manufactured.

The present invention that uses a stirring device that is a combination of a reciprocating rotary stirring device and a bubble discharging device has the following features.

(A) A homogeneous lightweight filler that uniformly contains closed cells is efficiently manufactured.

(B) Even if the cohesive soil in a natural state is used as it is, a highly dispersed and homogeneous lightweight filler can be efficiently produced.

<Examples> Next, the present invention will be described more specifically with reference to the drawings by Examples.

Example FIG. 1 shows an outline of an example of a stirring device A in which a reciprocating rotary stirring device B and a bubble discharging device C are combined. 2 is a plan view showing the arrangement of the bubble discharge pipe 7 in the container 4 of the agitator B as seen from below.

As shown in FIG. 1, a reciprocating rotary stirrer B is equipped with a foaming device 5 and a bubble discharge pipe 7, and an apparatus C is used.
Among them, as a filler 0.4 m ³ minutes before including bubbles, 180 kg of Kanto loam in a natural state, 530 water and 120 kg of cement-based solidifying material "Tough Rock" are mixed at 200 cycles / min for 3 minutes, and a foaming agent ( Escorts K) 13 1 kg of 100 bubbles are generated by the foaming device 5 using the compressed air from the compressor 12, and are guided to the bubble introduction pipe 6 and bubble discharge pipe 7 and discharged from the bubble discharge hole 8 for dispersed discharge. 2 bubbles created
After further mixing for 0.5 minutes, 0.5 m ^{3 of} homogeneous lightweight filler 10 was produced. The lightweight filler 10 produced in this manner was filled in the cavity 14 under the concrete foundation 16 around the pile 15 where the head was exposed due to ground subsidence, as shown in FIG. The filled lightweight filler had no bleeding, an average value of a unit volume weight of 1.0 g / cm ² , a P funnel flow time of 10 seconds, and a uniaxial compressive strength of 1.2 kgf / cm ² at 28 days of age.

In the reciprocating rotary stirrer B, two stirring blades 2 each having a triangular cross section 3 were attached to the upper left and right two pieces (reverse triangular shape in cross section), and four lower, front, rear, left and right (triangular shape cross section) in total to the stirring shaft 1. It has a structure and is arranged as shown in FIG. Reversed at every 1/4 rotation, strong up and down convection 11 and turbulent flow were strongly generated, and it was possible to dissolve the natural state loam and mix bubbles independently in a short time.

10mm sieve residue of lightweight filler is 8 against the input soil volume.
%, The coefficient of variation of the unit volume weight of the sample taken from the stirrer container 4 was 7%, and the coefficient of variation of the uniaxial compressive strength was 10%. When observing the cross-sectional structure of the solidified sample, it was found that fine closed cells were evenly distributed, and uneven distribution of bubbles was not found.

The soil properties were as follows.

Sand content 11.7% Silt content 69.6% Clay content 18.7% Specific gravity 2.711 Moisture content ratio 111.1% Unit volume weight 1.424t / m ³ <Effects of the invention> According to the present invention, as described above, other than natural clay, By effectively utilizing the cohesive soil in the state, it is possible to efficiently manufacture a lightweight filler having excellent properties that can be used for backfilling, backfilling, void filling, and the like.

[Brief description of drawings]

FIG. 1 shows an outline of an example of a stirrer in which a reciprocating rotary stirrer and a bubble discharge device are combined. FIG. 2 shows a schematic plan view of the arrangement of the bubble discharge pipes as seen from below. Further, FIG. 3 shows a state in which an exposed head portion of a support pile, which is caused by ground subsidence, is used as a cavity portion. A: Stirrer 8 ... Bubble discharge hole B ... Reciprocating rotary stirrer 9 ... Discharge bubble C ... Bubble discharger 10 ... Light weight filler 1 ... Stirrer shaft 11 ... Convection 2 ... Stirrer 12 …… Compressor 3 …… Stirring blade cross-sectional shape 13 …… Foaming agent 4 …… Container 14 …… Cavity 5 …… Foamer 15 …… Pile 6 …… Bubble introduction pipe 16 …… Concrete foundation 7 …… Bubbles Discharge pipe 17 ... Ground surface

Front page continued (72) Inventor Isao Nakakaku 2646 Asahigaoka-cho, Chiba City, Chiba Prefecture Nire no Kidai 1-2-404 (72) Inventor Yamashiro Ikumin 2-8 Honshio, Ichikawa City, Chiba Prefecture (72) Invention Koichirou Yamaguchi 15-33 Shimoyama-cho, Furukawa City, Ibaraki Prefecture (56) References JP-A-49-69753 (JP, A) JP-A-62-142299 (JP, A)

Claims (1)

[Claims] 1. A high-performance mixer comprising a reciprocating rotary stirrer and a bubble discharge device in combination, by stirring and mixing a material consisting of soil, a solidifying material, water, and bubbles formed by a foaming agent. A method for producing a lightweight filler, which comprises efficiently obtaining a light material that is homogeneous, fluid, and solidifying.