JPH0753280B2 - Treatment method of excavated shear mixed with air bubbles - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a bubble shield method of excavating while injecting bubbles in a civil engineering work and a method of treating a bubble mixed excavation shear generated by a bubble drilling method.

(Conventional technology and problems) Conventionally, bentonite mud has been used in the shield construction method and the like, and disposal of residual soil has been difficult. In order to solve this problem, a bubble shield construction method has been proposed in which the fluidity and water stoppage of excavated soil are secured by mixing air bubbles in place of bentonite. The general operating condition of the bubble-mixing method is that the foaming agent has a foaming ratio of 3 to 30 times per 10 parts by volume of the excavated soil.
The slump value of the bubble-mixed excavated slip thus obtained is often about 3 to 10 cm. In addition to the bubble shield method, a method of injecting bubbles into the hole is also known in boring and the like for the purpose of cooling the bit part and carrying out excavation shear.

As a method of treating excavation generated from these bubble-mixing methods, Japanese Patent Publication No. 58-47560 describes defoaming by natural notification, and Japanese Patent Publication No. 59-49999 discloses defoaming treatment by adding antifoaming material. Have been described. However, the silt / clay content and the cellulosic thickener are often contained in the drilling mixture containing bubbles, and the strong mud film produced by these components hinders the removal of bubbles, and also in the defoaming residue. Adds liquidity. For this reason, simple defoaming treatment is not yet sufficient. On the other hand, Japanese Patent Application No. Sho 63-259367, Japanese Patent Application No. 1-
13205 and Japanese Patent Application No. 1-13206 describe a technique in which a polymer flocculant is added and kneaded to the excavated soil left by the shield method, which does not contain a foaming agent.

(Problem of the Invention) The present invention can obtain a modified soil that solidifies a bubble-containing excavation shear in a short time, facilitates transportation, and can be used as a buried soil. The purpose is to provide a simple processing method.

Another object of the present invention is to provide a chemical and chemical injection method that facilitates storage, supply, mixing, etc. even in a construction site consisting of a narrow site in an urban area when reforming and solidifying a bubble-containing drilling shear. .

(Means for Solving the Problem) The present invention has a cation equivalent value of 2 meq / g for excavating gas bubbles.
It is constituted by adding and kneading the above cationic organic polymer flocculant.

The cationic organic polymer flocculant used in the present invention is known, and specifically, a reaction product obtained by condensing an amine or ammonia with epihalohydrin, alkylene dihalide, alkylene polyvalent epoxide, etc. as a linking agent (Japanese Patent Publication No. 38-26794, JP-B-41-17965, JP-B-51-22471, JP-B-56-37844, etc.) or condensation reaction products of dicyandiamide, melamine, guanidine or the like with formaldehyde as a linking agent or polyethyleneimine, polydimethyldiallylammonium chloride, dialkyl. Examples thereof include (co) polymerized pairs of salts of aminoalkyl methacrylates or dialkylaminoalkylacrylamides and / or quaternary products thereof.

The cationic organic polymer flocculant used in the present invention, whose main mechanism of action is to neutralize charge, is desired to have a high cation equivalent value, and one having a cation equivalent value of at least 2 meq / g or more. Exhibits good effects. The cation equivalent value is usually measured by colloid titration in PH4.0. In the practice of the present invention, since the cross-linking and adsorbing action of the cationic organic polymer flocculant also contributes to the effect, if the cation equivalent value is the same, the method of the high molecular weight flocculant exerts the effect with a small addition amount. . The method of kneading the bubble-containing drilling shear and the cation-made organic polymer coagulant is not particularly limited, and a kneader such as a continuous mixer or a forced stirring mixer is used, as well as a civil engineering machine such as a power shovel, a backhoe, or a screw conveyor. It can also be kneaded using.
In particular, the method of injecting into the screw conveyor section of the shield machine uses existing equipment, so it does not require a new processing site, etc., and can be easily implemented in urban areas.

The addition amount of the cationic organic polymer flocculant to be kneaded with the aerated excavated shear is 0.01-1 kg of the polymer content for 1 m ^{3 of the} aerated excavated shear. When the polymer flocculant is added in a powder state, mama powder is easily generated and a high performance stirring and kneading device is required. In order to easily knead with the bubble-containing drilling shear, it is desirable to add the polymer coagulant in the state of a constant viscosity liquid having a viscosity of 10,000 cp or less. The most inexpensive method for liquefying is to dissolve it in water and add it as an aqueous coagulant solution having a concentration of about 0.5 to 50%. However, in the case of avoiding an increase in water content such as when processing a high water content shear, a polymer flocculant which is liquefied by dispersing polymer fine particles in an oil or salt solution injection is preferable. Further, the method of using the cationic organic polymer flocculant in the present invention is not limited to single addition, and is added in combination with an inorganic flocculant such as aluminum sulfate and polyaluminum chloride, or a cationic organic polymer flocculant is added. After kneading, a high-grade aqueous resin, an anionic organic polymer flocculant, or an inorganic solidifying agent such as lime or cement may be added and kneaded.

(Function) The present invention is basically based on the fact that a cationic organic polymer coagulant is added and kneaded to a drill mixed with air bubbles to neutralize negative charges such as viscous particles and aggregate to remove fluidity.

If the mud film around the bubbles breaks (due to loss of hydrophilicity due to charge neutralization and aggregation), the bubbles easily aggregate by kneading and are released from the shear. The modified soil that has lost air bubbles and agglomerated has no fluidity and is easy to transport and fill.

Such an action is effective even when an anionic thickening agent such as CMC is present in the mud, and the cationic organic polymer flocculant forms an ion complex with these anionic polymers to make them water-insoluble. , To eliminate the thickening effect.

Such an effect cannot be expected from conventional antifoaming agents, and proves the superiority of the present invention.

(Example) Hereinafter, the present invention will be specifically described with reference to examples.

Synthesis example-1 1 equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen introducing pipe
In a 5-neck separable flask, 6 g of homopolymer of acryloyloxylethyltrimethylammonium chloride, 42 g of anhydrous sodium sulfate, 9 g of anhydrous aluminum sulfate.
8 g, ion-exchanged water (253 g), acrylamide (33.5 g) and acrylamidopropyldimethylbenzylammonium chloride (22.5 g) were charged, and the mixture was heated to 50 ° C. and purged with nitrogen.

to this. A dispersion of fine polymer particles was obtained by adding 1 ml of a 10% aqueous solution of 2.2'-azobis (2-amidinopropane) hydrochloride and conducting polymerization at 50 ° C for 10 hours with stirring.

This is referred to as Sample-1. The viscosity of this product is 2020cp at 25 ℃
And the polymer concentration was 0.
The viscosity of the solution dissolved in 5% was 10 cpd at 25 ° C, and the cation equivalent value at PH4.0 was 2.6 mep / g.

Synthesis Example-2 220 g of medium oil was charged in the same separable flask as used in Synthesis Example-1, 5 g of ICI Hypermer B-246 and 10 g of sorbitan monooleate were dissolved. Separately, a monomer solution prepared by dissolving 102 g of acrylamide and 198 g of methacryloyloxyethyltrimethylammonium chloride in 213 g of ion-exchanged water was prepared, and then poured into the aforementioned separable flask and stirred.

After purging with nitrogen for 30 minutes, the internal temperature was adjusted to 45 ° C., and then an acetone solution containing 50 mg of azobisisobutyronitrile was added to initiate polymerization. After the exotherm is no longer recognized, the temperature is raised to 5
The temperature was kept at 65 ° C. to complete the polymerization. 20 g of polyoxyethylene nonylphenyl ether was added to the obtained emulsion.
And a solution containing 20 g of polyoxyethylene sorbitan trioleate are referred to as Sample-2. The viscosity of Sample-2 is 98 at 25 ℃
The viscosity at 25 ° C. of the liquid having a polymer concentration of 0.5% dissolved in 1N saline was 25 cp, and the Catio equivalent value at PH 4.0 was 3.1 meq / g.

Synthesis Example-3 370 g of epichlorohydrin was charged into a 4-neck separable flask equipped with a stirrer, a thermometer, a reflux condenser and a 500-ml dropping funnel, and dimethyl was added under stirring with adjusting the internal temperature to 10 to 45 ° C. 400 g of 40% aqueous amine solution was added dropwise. After dropping for 2 hours, 40g of pentaethylenehexamine
Was added and the internal temperature was maintained at 65 to 70 ° C to carry out the condensation reaction. With the viscosity of the contents increased to 15,000 cp, a 25% sulfuric acid aqueous solution was added to adjust pH to 3 to stop the condensation reaction, and then the obtained polycation aqueous solution was diluted to a polymer concentration of 50%. This is referred to as Sample-3.

The viscosity of Sample-3 at 25 ° C was 5300 cp, and the cation equivalent value of the polymer was 7.1 meq / g.

Synthesis Example-4 A 2% aqueous solution of a commercially available powdery polymer flocculant, which is a (co) polymer of methacryloyloxyethyltrimethylammonium chloride and acrylamide, was prepared and tested.
The sample names and physical properties are shown in the table below. However, the 0.5% viscosity in the table is the viscosity at 25 ° C. of a liquid having a polymer concentration of 0.5% dissolved in 1N saline.

Example 1 20 kg of soil having a water content ratio of 41% and a silt clay content of 80% was placed in a forced kneading concrete mixer, and 7 times a 7-fold foam of a 0.3% aqueous solution of sodium polyoxyethylene alkylsulfonate was added and kneaded for 2 minutes.

The slump value of the aerated soil thus obtained was 5.5 cm. A cationic organic polymer flocculant was added to the aerated soil, the mixture was kneaded for 2 minutes, and the slump value was measured. The results are shown in Table-2.

The amount of chemicals added is shown in physical form.

Example-2 Carboxymethyl cellulose having a viscosity of 5000 cp of a 2% aqueous solution was used as an aqueous solution having a polymer concentration of 0.5%, and sodium polyoxyethylene alkylsulfonate was added to water in an amount of 0.1.
A solution in which the weight% was added and dissolved was fired 6.5 times with a stirrer. Moisture content 12%, FM3.
11 kg of commercially available sand of 11 and 2 kg of red soil having a water content ratio of 52% and a silt clay content of 48% were charged, the above-mentioned foam 6 was added, and the mixture was kneaded for 1 minute. The slump value of the aerated soil thus obtained was 6 cm.
The cationic polymer flocculant was added to the aerated soil, the mixture was kneaded for 2 minutes, and the slump value was measured. The results are shown in Table 3.

The amount of chemicals added is shown in physical form.

Claims (2)

[Claims] 1. A water-soluble cationic polymer flocculant having a cation equivalent value of 2 meq / g or more is added and kneaded in an amount of 0.01 to 1 kg per 1 m ³ of aeration mixed with air bubbles, so that fluidity can be obtained without a dehydration step. A method for treating excavated rocks containing air bubbles, which is characterized by eliminating water. 2. A cationic organic polymer flocculant having a viscosity of 10,000
The method for treating excavated mixture containing bubbles according to claim 1, characterized in that the mixture is added and kneaded in a liquid form of cp or less.