JPS6284177A - Production of grout - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to porous or cracked materials,
or to the production of powder suspensions intended for injection into very fine soil, in particular to improve its consistency.

It is known that some materials require a cement grouting process. For example, porous or corrosive water-eroded steel concrete, cracked concrete. In such cases, the infiltration of cement grout into such a material body is simultaneously limited by the particle size of the unit particles of cement and by agglomeration between the particles.

It is also known that alluvial soil is generally classified into two types: coarse alluvial soil and fine alluvial soil.

Coarse alluvial soils are easily cement grouted or bentonite cement grouted (in the grout, cement particles are suspended in water and bentonite is added as necessary to improve the stability of the suspension). can be injected.

Conversely, such grout cannot be injected into fine alluvial soil. This is because the pores of the soil are extremely small and cannot allow normal penetration and circulation of cement particles. Therefore, by using a silicate-based or silica-based solution that does not contain suspended particles and gelling it with a reagent, it is possible to inject into such fine soil.

However, this method has the disadvantage of giving rise to a certain soil contamination, especially at the level of free groundwater, and of poor permanence, as well, in that the resulting gel structure is not stable over time. This phenomenon, known as syneresis, is extremely harmful to gels obtained using silicate solutions.

For the reasons mentioned above, attempts have been made to inject cement grouts into porous or fractured materials or fine alluvial soils using very finely ground cement, i.e. cement whose particle size is less than about 15 microns. (in conventional cement, the particles generally range in size from 0 to 100 microns).

This finely ground cement is difficult to obtain and expensive;
For example, it costs more than 20 times the price of regular cement.

It has also been attempted to obtain the desired cement by separating ordinary cement transported by air into fine particles and coarse particles using a cyclone effect.

This method is expensive, the results are highly irregular, and
Grouting with such cement-containing grouts is inferior and unsatisfactory.

The present invention relates to a method using a grout consisting of a suspension of particles sufficiently fine, e.g. It is smaller than the interval.

The object of the invention is to mix a liquid, for example water, and a particulate product in the presence of a peptizer which separates the particles in the suspension from each other, and to partially settle the peptized suspension. grout which can be injected into porous or fissured materials or into fine alluvial soils, characterized in that it is stored in a container for a sufficient period of time to produce It is in the manufacturing method.

In the present invention, the peptizer is used in an amount of 0.5 to 5% by weight based on the particulate product.

By selecting the height of the container serving as the decantation tank, the decantation time, Q, and the level at which the filtrate is withdrawn, the maximum particle size of the particles contained in the discharged suspension can be determined. This maximum particle size is determined by the shape of the gap into which the particles are injected.

In the present invention, the suspension obtained in this way is used in fine alluvial soil,
or used to make grouts that can be injected into porous or cracked materials.

The remaining lower portion of the suspension may be used for other purposes or may be discarded.

In a preferred embodiment of the invention, the particulate solid material is cement and the liquid forming the suspension is water.

Also, in place of cement, silica powder, ground calcium carbonate may be used in the present invention, which may be treated separately and mixed immediately before injection, or separately injected into the treatment medium. They may also be brought into contact with each other in the field.

In addition, in the present invention, a silicate solution, a silica liquid, or any liquid that reacts with the granular solid product after injection can be used as the suspension.

Examples of deflocculants added to the solid particle suspension include melamine resin, sodium naphthalene sulfonate, sodium polyphosphate, sodium alkylnaphthalene sulfonate,
Sodium alkyl sulfonate or ammonium polyacrylate.

Another object of the invention is a suspension of granular solid products obtained by the above method.

In order to provide a better understanding of the present invention, some embodiments will be described based on the following examples. The examples are illustrative and are not intended to limit the invention in any way.

Example 1 A grout consisting of an aqueous cement suspension intended for injection into fine sand with a particle size in the range 0 to 0.31 mm is prepared as follows.

Cement 1-CLK45 is dispersed in 500 kg of water 8301 in a high turbulence mixer, mixing is carried out for about 3 minutes, then 2.5-7.5 k of melamine resin, which acts as a deflocculant,
g and stirring for about 2 minutes.

The mixture thus prepared is placed in a tank with a cross section of 2M. This tank is equipped with a drain cock located 25 cIll below the liquid level. Sedimentation is carried out for 1 hour.

The extraction cock is then opened and a grout 51 containing 30-35% of the initially used 500 kg of cement is obtained.

The cement particles contained in this grout have a particle size of 0 to 1
0 microns, whereas the initially used cement had a particle size of 0-100 microns.

The grout thus obtained can be stored in a tank equipped with an agitator and poured in a conventional manner into soil consisting of sand with a grain size of 0 to 0.3 mm.

In one variant of the method, with a settling time of 30 minutes, a grout 50ON containing 50-55% of the initial cement weight and having a particle size of 0-15 microns can be removed.

Example 2 300 kg of silica powder with a particle size of 0 to 50 microns was placed in a high turbulence mixer to make an aqueous silica suspension intended for injection into fine soil with a particle size of O to 0.3 ff1 m. The water you put in it? dispersed inside. The mixture is combined for about 3 minutes and 3 to 9 kg of peptizer, for example naphthalene sulfonate, are added.

Next, this solution was taken out 25 cm from the liquid level and placed in a tank with a cross section of 2M equipped with a cock, and after settling for 3 hours, the solution was removed from the top of the cock. ! ! Remove the cloudy liquid.

First FJI Q, the density of the suspension is 1.147, but the density of the extracted suspension is 1.120-1.125,
It can be easily injected into soils such as the fine soil of Example 1, turning the soil into honey.

As a comparative example, this initial suspension cannot be injected as it is self-filtering.

On the contrary, the suspension or suspension obtained according to the present invention can be poured very easily at low pressure, and the pores of the soil are closed with silica powder, making the soil a honeydew.

Example 4 Injection of a suspension mixture of silica powder and calcium carbonate powder into fine soil is carried out as follows.

First, a suspension of silica powder is prepared as described in Example 2. Separately, place crushed marble (CaC) in a high turbulence mixer.
03) Add 300 kg of water and 100 (l) of suspension. Add 6 kg of naphthalene as a deflocculant, let it settle for about 45 minutes to 1 hour, and extract the suspension up to 25 cm from the initial water surface. The particle size of calcium carbonate is 0
~50 microns, and the initial density of this suspension is 1.1
6 to 1.18.

In the suspension obtained in the present invention, the particle size of calcium carbonate is 0 to 2.
At 0 microns, the density is approximately 1.14-1.16.

Mix the two suspensions obtained as above in equal volumes,
This mixture is poured into soil consisting of fine sand with a particle size of 0-0.3 mm. In this way a watertight and resistant sand is obtained.

In this variant, these two suspensions may be injected into the soil one after the other.

Example 4 A suspension of calcium carbonate powder in a silica solution or a sodium silicate solution that can be injected into fine soil is prepared as follows.

First, a suspension of calcium carbonate is prepared as in Example 3 above, and this suspension is mixed with 10 to 2 silica (Sing).
1 volume of calcium carbonate suspension mixed with 5% by weight sodium silicate solution or silica liquid in the following proportions:
0.5-1.5 volumes of silicate, solution or silica fluid The mixture thus obtained is injected into soil consisting of particles with a particle size of 0-0.3 mm to form a water-tight and resistant soil. Soil is obtained.

The above embodiments do not limit the present invention in any way,
Any desired modifications may be made within the scope of the invention.

Procedural amendment (method) 2. Title of the invention Grout manufacturing method 3. Relationship with the person making the amendment Applicant name
4. Agent

Claims (9)

[Claims] (1) Mixing a liquid, such as water, and a particulate product in the presence of a peptizer, which separates the particles in the suspension from each other, and the peptized suspension is heated to such an extent that partial sedimentation occurs. A method for producing a grout that can be injected into porous or fissured materials or into fine alluvial soil, characterized by storing it in a container for a sufficient period of time and drawing out a volume of suspension above a certain level in the container. . (2) The particulate product is cement or silica powder,
or calcium carbonate powder, the method according to item (1) above. (3) Items (1) and (2) above, characterized in that the liquid is water, silica solution, or sodium silicate solution.
) The method described in any of the above. (4) Items (1) to 1 above, wherein the peptizing agent is melamine resin, sodium naphthalene sulfonate, sodium polyphosphate, sodium alkylnaphthalene sulfonate, sodium alkyl sulfonate, or ammonium polyacrylate. The method described in any of paragraph (3). (5) The method according to any one of items (1) to 4 above, wherein the peptizer is used in an amount of 0.5 to 5% by weight based on the particulate product. (6) The settling time and the height of the extracted suspension are determined so as to obtain a particle size of 15 microns or less, preferably 10 microns or less.
The method described in any of the paragraphs. (7) Items (1) to (6) above, characterized in that, for example, a suspension of silica powder and a suspension of calcium carbonate powder are prepared separately and both are mixed before being injected into the soil. The method described in any of the paragraphs. (8) For example, according to any one of items (1) to (6) above, characterized in that the liquid of silica powder and the suspension of calcium carbonate powder are prepared separately and subsequently injected into the soil. the method of. (9) For the purpose of injecting into fine soil, or porous material, or cracked material, characterized by being obtained by the method described in any of paragraphs (1) to (8) above. suspension.