JP7391485B2 - soil cement - Google Patents

Description

The present invention relates to soil cement and a method for producing the same.

Soil cement is a mixture of soil and cement-based solidifying material, or by adding water to this. Construction methods that use soil cement include soil improvement methods, pile retaining methods, foundation pile methods, and backfilling methods. These methods typically involve adding cement milk, which is a pre-mixed mixture of a cementitious hardening agent and water, to the soil. The above cementitious solidifying materials include ordinary Portland cement, low-heat Portland cement, moderate-heat Portland cement, early strength Portland cement, blast furnace cement, and Portland cement with blast furnace slag, limestone powder, fly ash, fine silica powder, calcium carbonate, and gypsum. Mixed cement obtained by mixing these materials is used. The amount of solidifying agent and water to be added is determined depending on the physical properties of the soil for which soil cement is to be created, such as the soil quality such as sand, silt, and clay, its water content, and the construction form and purpose. Ru.

Foundation pile construction methods are broadly divided into cast-in-place pile construction methods and ready-made pile construction methods. The cast-in-place pile method is a construction method in which cylindrical reinforcing bars assembled on-site are dropped into the excavated ground, and then fresh concrete is poured into the hole and hardened to form a pile. On the other hand, the ready-made pile method is a method of embedding ready-made concrete piles or steel pipe piles into the ground, and is divided into the driven pile method and the embedded pile method. In the driven pile method, the piles are directly driven into the ground, which tends to generate a lot of noise, so the buried pile method is widely used in Japan.

Patent Document 1 discloses a highly fluid product containing (A) at least one specific (poly)glycoside and (B1) at least one nonionic surfactant represented by a specific formula. A dispersant composition for a hydraulic composition is disclosed that provides a hydraulic composition with a high temperature.

Japanese Patent Application Publication No. 2018-184339

In the buried pile construction method, cement milk, called a root hardening solution, is injected into the tip of the pile in order to strengthen the bearing capacity of the pile buried in the ground. Soil cement with a relatively low water/hydraulic powder ratio is formed in the foot protection area to maintain strength, but if temperature cracks occur in the foot protection area due to a rise in temperature due to the heat generated by hydration of the soil cement, the pile The supporting capacity of the product will be reduced.
In addition, as a method to prevent temperature cracking, it is possible to suppress the amount of temperature rise in soil cement to a low level and to improve heat dissipation conditions. In order to suppress the temperature rise of soil cement, it is possible to add super retardants such as carboxylates, gluconates, or fluorosilicides to the soil cement, which retard the hydration reaction of cement. It only has the effect of delaying the hydration time of cement, that is, extending the setting time, and the final temperature rise amount and speed are the same or slightly smaller than soil cement without adding anything, so the effect is not very expected. Can not.

The present invention provides a soil cement that suppresses temperature rise due to heat generated by hydration when hydraulic powder and water come into contact with water, and also suppresses delay in setting time, a method for manufacturing the same, a soil improvement body, and a soil improvement. provide a method.

The present invention is a soil cement containing the following component (A), the following component (B), hydraulic powder, soil containing clay minerals, and water,
The total content of components (A) and (B) is 0.05 parts by mass or more and 4 parts by mass or less based on 100 parts by mass of the hydraulic powder, and the content of clay mineral is 100 parts by mass of the hydraulic powder. 1 part by mass or more and 20 parts by mass or less based on soil cement.
(A) Component: At least one type of (poly)glycoside having an alkyl group having 8 to 20 carbon atoms or an alkenyl group having 8 to 20 carbon atoms and having a degree of sugar condensation of 1 to 5. (B) Component : A nonionic surfactant represented by the following general formula (B11), a nonionic surfactant represented by the following general formula (B12), and a nonionic surfactant represented by the following general formula (B13). at least one nonionic surfactant selected from

[During the ceremony,
R ¹¹ , R ³¹ : each from an alkyl group having 8 to 22 carbon atoms, an alkenyl group having 8 to 22 carbon atoms, an aralkyl group having 8 to 22 carbon atoms, and a substituted aryl group having 8 to 22 carbon atoms; Selected group R ²¹ : selected from an alkyl group having 7 to 21 carbon atoms, an alkenyl group having 7 to 21 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, and a substituted aryl group having 7 to 21 carbon atoms. Group R ²² : Alkylene group having 2 to 4 carbon atoms X ¹ : Group selected from an alkyl group having 1 to 3 carbon atoms, and a group represented by -R ²² -OH R ³² , R ³³ : Each is hydrogen Atom or alkyl group having 1 to 3 carbon atoms AO: Alkyleneoxy group having 2 to 4 carbon atoms p1: Number from 3 to 100 q1, r1: Each number is 0 or more, and the sum of q1 and r1 is , a number from 0.5 to 100. ]

The present invention also provides a method for producing soil cement, which comprises mixing the component (A), the component (B), hydraulic powder, soil containing clay minerals, and water,
The total amount of components (A) and (B) mixed is 0.05 parts by mass or more and 4 parts by mass or less per 100 parts by mass of the hydraulic powder, and the mixed amount of the clay mineral is 100 parts by mass of the hydraulic powder. 1 part by mass or more and 20 parts by mass or less.

The present invention also provides a ground improvement body containing the component (A), the component (B), hydraulic powder, water, and soil containing clay minerals,
The total content of components (A) and (B) is 0.05 parts by mass or more and 4 parts by mass or less based on 100 parts by mass of the hydraulic powder, and the content of clay mineral is 100 parts by mass of the hydraulic powder. 1 part by mass or more and 20 parts by mass or less relative to the ground improvement body.

The present invention also provides a ground improvement method in which the component (A), the component (B), hydraulic powder, soil containing clay minerals, and water are mixed,
The total amount of components (A) and (B) mixed is 0.05 parts by mass or more and 4 parts by mass or less per 100 parts by mass of the hydraulic powder, and the mixed amount of the clay mineral is 100 parts by mass of the hydraulic powder. It relates to a ground improvement method in which the amount is 1 part by mass or more and 20 parts by mass or less.

According to the present invention, a soil cement, a method for producing the same, a soil improvement body, and a soil cement that suppress a temperature rise due to hydration heat generation when hydraulic powder and water come into contact with each other and suppress a delay in setting time, An improved method is provided.

Schematic diagram showing the method for measuring the amount of adiabatic temperature increase due to heat generated by hydration of cement in an example

Although the details of the effect expression mechanism of the present invention are unknown, it is presumed as follows. Since polyols such as sugars generally have the property of adsorbing to cement particles, it is presumed that component (A) (poly)glycoside adsorbs to the surface of cement particles. In addition, the nonionic surfactant of component (B) has a predetermined HLB, so it has increased lipophilicity, coordinates with the alkyl group or alkenyl group of component (A), and is attached to the cement particle surface. It is assumed that an oil film is formed. It is thought that this oil film prevents contact between cement particles and water, thereby suppressing heat generation due to hydration of cement. On the other hand, it is thought that component (A) chelates calcium ions eluted from cement particles and inhibits the growth of nuclei of calcium silicate hydrate (CSH), thereby delaying the coagulation of cement milk. It is thought that when clay minerals coexist there, calcium ions are taken in between the clay layers, and the calcium ions are protected from the chelating action of component (A), thereby suppressing setting delay.

[Soil cement and its manufacturing method]
The present invention is a soil cement containing component (A), component (B), hydraulic powder, soil containing clay minerals, and water,
The total content of components (A) and (B) is 0.05 parts by mass or more and 4 parts by mass or less based on 100 parts by mass of the hydraulic powder, and the content of clay mineral is 100 parts by mass of the hydraulic powder. 1 part by mass or more and 20 parts by mass or less based on soil cement.

<(A) component>
Component (A) is at least one type of (poly)glycoside having an alkyl group having 8 to 20 carbon atoms or an alkenyl group having 8 to 20 carbon atoms, and having a degree of sugar condensation of 1 to 5.

The number of carbon atoms in the alkyl group or alkenyl group of component (A) is 8 or more and 20 or less, preferably 18 or less, from the viewpoint of ease of forming an association with component (B) and water solubility. It is preferably 16 or less, more preferably 14 or less, even more preferably 12 or less.

Component (A) preferably has an alkyl group having 8 or more and 20 or less carbon atoms.

The degree of sugar condensation of component (A) is 1 or more and 5 or less, preferably 4 or less, more preferably 3 or less, still more preferably 2 or less, from the viewpoint of water solubility.

Specific examples of the sugar constituting component (A) include glucose, maltose, and sucrose. Component (A) preferably has at least one (poly)glucoside having an alkyl group having 8 to 20 carbon atoms or an alkenyl group having 8 to 20 carbon atoms and having a degree of sugar condensation of 1 to 5. At least one type of (poly)glucoside having an alkyl group having 8 to 20 carbon atoms and a degree of sugar condensation of 1 to 5 is preferred.

<(B) component>
Component (B) is a nonionic surfactant represented by the general formula (B11) [hereinafter referred to as component (B11)], a nonionic surfactant represented by the general formula (B12) [hereinafter referred to as component (B11)], , component (B12)] and a nonionic surfactant represented by the general formula (B13) [hereinafter referred to as component (B13)], the nonionic surfactant has an HLB value of 2. At least one nonionic surfactant having a number of 11 or less.

The HLB of component (B) is 2 or more, preferably 2.5 or more, more preferably 3 or more, and 11 or less, preferably less than 11, more preferably 10 or less, from the viewpoint of suppressing hydration heat generation of soil cement. , more preferably 9 or less, even more preferably 7 or less.
Here, HLB is an abbreviation for Hydrophile-Hydrophobic Balance, and serves as an index for knowing whether a compound is hydrophilic or lipophilic. Typical nonionic surfactants have values of 0 to 20. The smaller the HLB value, the stronger the lipophilicity.

In the present invention, the HLB of components (B11), (B12), and (B13) are values calculated by the Griffin method. HLB according to the Griffin method is calculated from the following formula.
HLB=20×sum of formula weights of hydrophilic parts/molecular weight

Furthermore, when two or more types of nonionic surfactants are used as the component (B), it is sufficient that the HLB of the mixture of the compositions is within the above-mentioned predetermined range.
Note that when two or more types of nonionic surfactants are used, the HLB is calculated as a weighted average value of the HLB and weight ratio of each nonionic surfactant.

In general formula (B11), R ¹¹ is preferably a group selected from an alkyl group having 8 to 22 carbon atoms, an alkenyl group having 8 to 22 carbon atoms, and a substituted aryl group having 8 to 22 carbon atoms. , more preferably a group selected from alkyl groups having 8 or more and 22 or less carbon atoms. The number of carbon atoms in the alkyl group having 8 to 22 carbon atoms is preferably 10 or more, and preferably 20 or less, more preferably 18 or less, still more preferably 16 or less, and still more preferably 14 or less. The number of carbon atoms in the alkenyl group having 8 or more and 22 or less carbon atoms is preferably 10 or more, and preferably 20 or less, more preferably 18 or less, still more preferably 16 or less, and even more preferably 14 or less. The number of carbon atoms in the substituted aryl group having 8 or more and 22 or less carbon atoms is preferably 14 or more and preferably 22 or less. Examples of the substituted aryl group include a substituted aryl group substituted with an aralkyl group having 8 to 16 carbon atoms, such as a monobenzylphenyl group, a dibenzylphenyl group, a monostyrenated phenyl group, and a distyrenated phenyl group, an octylphenyl group, and a phenyl group substituted with an alkyl group having 8 to 12 carbon atoms such as nonylphenyl group.
In general formula (B11), AO is an alkyleneoxy group having 2 or more and 4 or less carbon atoms. It is preferable that AO contains an alkyleneoxy group having 2 or 3 carbon atoms, and further an alkyleneoxy group having 2 carbon atoms.
In general formula (B11), p1 is the average number of moles of AO added, and from the viewpoint of water solubility and fluidity of soil cement, it is preferably 1 or more, more preferably 3 or more, and preferably 50 or less, more Preferably it is 60 or less, more preferably 45 or less, even more preferably 20 or less, even more preferably 4.5 or less, even more preferably 3 or less.

In general formula (B12), R ²¹ is preferably a group selected from alkyl groups having 7 or more and 21 or less carbon atoms. The carbon number of the alkyl group having 7 or more and 21 or less carbon atoms is 7 or more and preferably 17 or less.
In general formula (B12), R ²² is preferably an alkylene group having 2 carbon atoms.
In the general formula (B12), the alkyl group having 1 to 3 carbon atoms in X ¹ is preferably an alkyl group having 1 carbon number. Furthermore, the group represented by -R ²² -OH is preferably one in which R ²² is an alkylene group having 2 carbon atoms. X ¹ is preferably an alkyl group having 1 to 3 carbon atoms.

In general formula (B13), R ³¹ is preferably a group selected from alkyl groups having 8 to 22 carbon atoms. The number of carbon atoms in the alkyl group having 8 to 22 carbon atoms is preferably 10 or more, and preferably 18 or less, more preferably 16 or less, and even more preferably 14 or less.
In general formula (B13), AO is an alkyleneoxy group having 2 or more and 4 or less carbon atoms. It is preferable that AO contains an alkyleneoxy group having 2 or 3 carbon atoms, and further an alkyleneoxy group having 2 carbon atoms.
In general formula (B13), q1 and r1 are each a number of 0 or more, and the sum of q1 and r1 is preferably 1.0 or more, more preferably 1.5 or more, and preferably 6 or less, It is more preferably 4.5 or less, still more preferably 3.5 or less, even more preferably 3.0 or less, even more preferably 2.5 or less.

Component (B1) is preferably at least one selected from component (B12) and component (B13), more preferably at least one selected from component (B12), from the viewpoint of suppressing the rise in the adiabatic temperature of soil cement. It is.

<Composition, optional ingredients, etc.>
In the soil cement of the present invention, the content of component (A) is preferably 0.01 part by mass or more, more preferably 0.04 parts by mass or more, more preferably 0.07 parts by mass or more, even more preferably 0.10 parts by mass or more, and from the viewpoint of retarding the hydration reaction of soil cement, preferably 1.0 parts by mass or less, The amount is more preferably 0.5 parts by mass or less, still more preferably 0.3 parts by mass or less, even more preferably 0.2 parts by mass or less.

In the soil cement of the present invention, the content of component (B) is preferably 0.1 part by mass or more, more preferably 0.2 parts by mass or more, more preferably 0.3 parts by mass or more, and preferably 2.0 parts by mass or less, more preferably 1.0 parts by mass or less, still more preferably 0.6 parts by mass or less, and even more Preferably it is 0.4 parts by mass or less.

The soil cement of the present invention has a total content of components (A) and (B) of 0.05 parts by mass or more based on 100 parts by mass of hydraulic powder, from the viewpoint of suppressing the rise in the adiabatic temperature of the soil cement. , preferably 0.1 parts by mass or more, more preferably 0.15 parts by mass or more, still more preferably 0.2 parts by mass or more, even more preferably 0.3 parts by mass or more, and retards the hydration reaction of soil cement. From the viewpoint of performance, 4.0 parts by mass or less, preferably 2.0 parts by mass or less, more preferably 1.0 parts by mass or less, even more preferably 0.7 parts by mass or less, even more preferably 0.5 parts by mass. It is as follows.

In the soil cement of the present invention, the mass ratio (A)/(B) between the content of the component (A) and the content of the component (B) is preferably 0 from the viewpoint of suppressing the adiabatic temperature rise of the soil cement. .05 or more, more preferably 0.1 or more, even more preferably 0.13 or more, and preferably 2.0 or less, more preferably 1.0 or less, still more preferably 0.5 or less, even more preferably 0 .4 or less.

The soil cement of the present invention contains hydraulic powder. Hydraulic powder refers to a powder that has physical properties that harden through a hydration reaction, and includes cement, gypsum, and the like. Preferably, cements such as ordinary Portland cement, Belite cement, moderate heat cement, early strength cement, ultra early strength cement, and sulfate-resistant cement are used, and these are also combined with posolan action and/or such as blast furnace slag, fly ash, and silica fume. Blast furnace slag cement, fly ash cement, silica fume cement, etc. to which powder having latent hydraulic properties, stone powder (calcium carbonate powder), etc. are added may also be used. Here, the hydraulic powder is selected from powders with physical properties such as cement that harden through hydration reactions, powders with pozzolanic action, powders with latent hydraulic properties, and stone powders (calcium carbonate powders). In the present invention, if the powder contains powders such as Further, when the powder having the physical property of hardening through a hydration reaction contains a high-strength admixture, the amount of the high-strength admixture is also included in the amount of the hydraulic powder. This also applies to parts by mass, mass ratio, etc., which are related to the mass of the hydraulic powder.

The soil cement of the present invention contains soil containing clay minerals. Examples of soil include sand, silt, clay, and the like. For these, soil generated at the construction site can be used. In addition, when the composition containing components other than soil of the soil cement of the present invention is injected into the ground as a high-pressure jet fluid for the purpose of soil improvement etc., the soil in the ground is involved in the jet fluid. Good for making cement. The soil cement of the present invention can be used, for example, as fluidized soil, ie, invert mortar, etc. in tunnel construction.

Clay minerals include kaolin (kaolinite, dickite, nacrite, etc.), serpentine (lizardite, antigorite, chrysotile, etc.), mica clay minerals (illite, sericite, glauconite, celadonite, etc.), chlorite, vermiculite. , smectite (montmorillonite, beidellite, nontronite, saponite, hectorite, etc.). Although the type and amount of clay contained in soil vary, the present invention can target soil containing clay minerals selected from montmorillonite and kaolinite, for example.

In the soil cement of the present invention, the soil content is preferably 1 part by mass or more, more preferably 5 parts by mass or more, and The amount is preferably 10 parts by mass or more, and preferably 300 parts by mass or less, more preferably 200 parts by mass or less, and still more preferably 100 parts by mass or less.

In the soil cement of the present invention, the clay mineral content is preferably 0.5 parts by mass or more, more preferably 1 part by mass, from the viewpoint of retardation of setting of the soil cement, based on 100 parts by mass of the hydraulic powder. Above, more preferably 2 parts by mass or more, still more preferably 5 parts by mass or more, even more preferably 7 parts by mass or more, and preferably 20 parts by mass or less, more preferably 15 parts by mass or less, still more preferably 13 parts by mass. The amount is more preferably 10 parts by mass or less.

The soil cement of the present invention has a water/hydraulic powder ratio of preferably 20% or more, more preferably 30% or more, even more preferably 40% or more, and preferably 200% or more, from the viewpoint of the compressive strength of the soil cement. % or less, more preferably 10% or less, still more preferably 80% or less. Here, water/hydraulic powder is the mass percentage (mass %) of water and hydraulic powder in soil cement, and is calculated as water/hydraulic powder×100. The water/hydraulic powder ratio may be expressed as W/P, and if the hydraulic powder is cement, it may be expressed as W/C.

In the soil cement of the present invention, the mass ratio of the total content of components (A) and (B) to the content of clay minerals (clay minerals/((A) + (B))) is From the viewpoint of setting retardation, preferably 2 or more, more preferably 4 or more, still more preferably 8 or more, even more preferably 15 or more, even more preferably 20 or more, and preferably 100 or less, more preferably 60 or less. , more preferably 40 or less, even more preferably 35 or less.

The soil cement of the present invention can further contain (C) an antifoaming agent [hereinafter referred to as component (C)]. However, component (A) and component (B) are excluded from component (C).

Component (C) includes silicone antifoaming agents, fatty acid ester antifoaming agents, ether antifoaming agents, polyalkylene oxide antifoaming agents, alkyl phosphate antifoaming agents, and acetylene glycol antifoaming agents. One or more antifoaming agents selected from:
Component (C) is preferably one or more antifoaming agents selected from silicone antifoaming agents, fatty acid ester antifoaming agents, and ether antifoaming agents.
The silicone antifoaming agent is preferably dimethylpolysiloxane.
The fatty acid ester antifoaming agent is preferably a water-insoluble polyalkylene glycol fatty acid ester.
The ether antifoaming agent is preferably polyalkylene glycol alkyl ether.
The polyalkylene oxide antifoaming agent is preferably a block copolymer of ethylene oxide and propylene oxide.
Among the alkyl phosphate antifoaming agents, tributyl phosphate, isotributyl phosphate, and sodium octyl phosphate are preferred.
Among the acetylene glycol antifoaming agents, 2,4,7,9-tetramethyl-5-decyne-4,7-diol or its alkylene oxide adduct is preferred.

As component (C), a fatty acid ester antifoaming agent is preferable from the viewpoint of suppressing a decrease in the strength of soil cement.

The silicone antifoaming agent is preferably an emulsion type that is compatible with water. Commercially available emulsion-type silicone antifoaming agents that are compatible with water include KM-70, KM-73A [both manufactured by Shin-Etsu Silicone Co., Ltd.], and the TSA series (Momentive Performance Materials Japan LLC). ), FS Antifoam series [Dow Corning Toray Co., Ltd.], Antifoam E-20 [Kao Corporation], etc.

Commercially available products of polyalkylene glycol fatty acid esters, which are fatty acid ester antifoaming agents, include Rheodol TW-L120 (Kao Corporation), Nicofix, Foamrex (all manufactured by NICCA Chemical Co., Ltd.), and the like.

As a commercially available product of polyalkylene glycol alkyl ether, which is an ether defoaming agent, Defoaming Agent No. 1. Antifoaming agent No. 5. Antifoaming agent No. 8 (all manufactured by Kao Corporation), SN Deformer 15-P, and Formaster PC (all manufactured by Sannopco Corporation).

Among polyalkylene oxide antifoaming agents, commercially available block copolymers of polyethylene oxide and polypropylene oxide include block copolymers of ethylene oxide and propylene oxide, such as PLURONIC (trademark) products [BASF Corporation].

Commercially available acetylene glycol antifoaming agents include SURFYNOL (trademark) 400 series (Air Products and Chemicals) and the like.

When the soil cement of the present invention contains component (C), the content thereof is preferably 0.01 parts by mass or more based on 100 parts by mass of the hydraulic powder from the viewpoint of antifoaming properties of the soil cement. , more preferably 0.05 parts by mass or more, and preferably 2 parts by mass or less, more preferably 1 part by mass or less.

The soil cement of the present invention can further contain (D) a dispersant [hereinafter referred to as component (D)]. Examples of the dispersant include one or more dispersants selected from lignin sulfonic acid polymers, polycarboxylic acid polymers, naphthalene polymers, melamine polymers, and phenol polymers, and from the viewpoint of dispersibility. Preferably one or more dispersants selected from polycarboxylic acid copolymers, lignin sulfonic acid copolymers, and naphthalene sulfonic acid copolymers, more preferably lignin sulfonic acid copolymers, and one or more dispersants selected from polycarboxylic acid polymers.

Examples of naphthalene-based polymers include naphthalene sulfonic acid formaldehyde condensates (e.g., Mighty 150 manufactured by Kao Corporation); examples of melamine-based polymers include melamine sulfonate formaldehyde condensates (e.g., Mighty 150-V2 manufactured by Kao Corporation); Examples of the polymer include phenolsulfonic acid formaldehyde condensate (compounds described in JP-A-49-104919, etc.), and examples of the ligninsulfonic acid polymer include ligninsulfonate (Pozolith No. 70 manufactured by BASF, Borregard). Ultrazin NA manufactured by Nippon Paper Chemicals Co., Ltd., Sunextract manufactured by Nippon Paper Chemicals Co., Ltd., Vanillex, Pearlex, etc.) can be used.

Examples of polycarboxylic acid copolymers include polymers of (meth)acrylic acid, copolymers of monoesters of polyalkylene glycol and (meth)acrylic acid, and carboxylic acids such as (meth)acrylic acid (for example, Copolymers of unsaturated alcohols containing polyalkylene glycol and carboxylic acids such as (meth)acrylic acid, copolymers of unsaturated alcohols containing polyalkylene glycol and maleic acid, etc. A copolymer with dicarboxylic acid, etc. can be used. Here, (meth)acrylic acid means a carboxylic acid selected from acrylic acid and methacrylic acid.

When the soil cement of the present invention contains component (D), the content is preferably 0.01 parts by mass or more, more preferably The amount is 0.05 parts by mass or more, preferably 2 parts by mass or less, and more preferably 1 part by mass or less.

The soil cement of the present invention can also contain other components. Examples include AE agents, retarders, foaming agents, thickeners, foaming agents, waterproofing agents, fluidizing agents, etc. (excluding those corresponding to components (A) to (D)).

The present invention is a method for producing soil cement, which comprises mixing component (A), component (B), hydraulic powder, soil containing clay minerals, and water.
The total amount of components (A) and (B) mixed is 0.05 parts by mass or more and 4 parts by mass or less per 100 parts by mass of the hydraulic powder, and the mixed amount of the clay mineral is 100 parts by mass of the hydraulic powder. Provided is a method for producing soil cement in which the amount of soil cement is 1 part by mass or more and 20 parts by mass or less.

In the soil cement manufacturing method of the present invention, component (C) can be further mixed.
In the method for producing soil cement of the present invention, component (D) can be further mixed.
In the method for producing soil cement of the present invention, the embodiments described for the soil cement of the present invention can be applied as appropriate.
Component (A), component (B), component (C), and component (D) are the same as those described in the soil cement of the present invention.
In the method for producing soil cement of the present invention, the mixing amount of component (A), component (B), component (C), component (D), hydraulic powder, and soil containing clay minerals, and the various mass ratios are as follows: , the content of each component described in the soil cement of the present invention can be replaced with the mixing amount.

The method for producing soil cement of the present invention involves preparing a slurry by mixing component (A), component (B), hydraulic powder, water, and clay mineral in advance, and then mixing the slurry with soil. Can be manufactured by mixing.
In addition, the method for producing soil cement of the present invention includes adding in advance component (A), component (B), optionally component (C), optionally component (D), hydraulic powder, water, and clay. It can be manufactured by mixing minerals to prepare a slurry and then mixing the slurry with soil.

The present invention is a ground improvement body containing component (A), component (B), hydraulic powder, water, and soil containing clay minerals,
The total content of components (A) and (B) is 0.05 parts by mass or more and 4 parts by mass or less based on 100 parts by mass of the hydraulic powder, and the content of clay mineral is 100 parts by mass of the hydraulic powder. Provided is a ground improvement body in which the amount is 1 part by mass or more and 20 parts by mass or less.

The ground improvement body of the present invention can further contain component (C).
The ground improvement body of the present invention can further contain component (D).
The soil cement of the present invention and the method for producing the same can be suitably applied to the ground improvement body of the present invention.
Component (A), component (B), component (C), and component (D) are the same as those described in the soil cement of the present invention.
In the ground improvement body of the present invention, the content of soil containing component (A), component (B), component (C), component (D), hydraulic powder, and clay mineral, and various mass ratios are as follows. It is the same as the soil cement of the invention.

The present invention is a ground improvement method in which component (A), component (B), hydraulic powder, soil containing clay minerals, and water are mixed,
The total amount of components (A) and (B) mixed is 0.05 parts by mass or more and 4 parts by mass or less per 100 parts by mass of the hydraulic powder, and the mixed amount of the clay mineral is 100 parts by mass of the hydraulic powder. Provided is a ground improvement method in which the amount is 1 part by mass or more and 20 parts by mass or less.

In the ground improvement method of the present invention, component (C) can be further mixed.
In the ground improvement method of the present invention, component (D) can be further mixed.
The soil cement of the present invention, its manufacturing method, and the embodiments described in the soil improvement body of the present invention can be applied as appropriate to the ground improvement method of the present invention.
Component (A), component (B), component (C), and component (D) are the same as those described in the soil cement of the present invention.
In the ground improvement method of the present invention, the mixing amount of the soil containing component (A), component (B), component (C), component (D), hydraulic powder, and clay mineral, and the various mass ratios are as follows: The content of each component described in the soil cement of the present invention can be replaced with the mixing amount.

In the ground improvement method of the present invention, component (A), component (B), hydraulic powder, water, and clay mineral are mixed in advance to prepare a slurry, and then the slurry and soil are mixed. can do.
In addition, the ground improvement method of the present invention includes adding (A) component, (B) component, optionally (C) component, optionally (D) component, hydraulic powder, water, and clay minerals in advance. After preparing a slurry, the slurry and soil can be mixed.

In the ground improvement method of the present invention, the slurry and soil have a volume ratio (slurry)/(soil) of preferably 0.1 or more, more preferably 0.2 or more, and preferably 1.5. Below, it is more preferably mixed at 1.0 or less.

The method for producing soil cement or the method for improving the ground is, for example, the mixing water containing the component (A), the component (B), optionally the component (C), and optionally the component (D) of the present invention, and water. Examples include those including a step of mixing hard powder and clay minerals to obtain a slurry, and a step of mixing the slurry with soil. In the step of obtaining the slurry, the mixer used is not particularly limited as long as it can mix uniformly, but generally a type that stirs with a mechanical stirring blade is often used. While stirring, the (A) component, (B) component, optionally the (C) component, optionally the (D) component, water, hydraulic powder, and clay mineral of the present invention are added to this mixer etc. while stirring. A slurry is obtained by kneading for at least 10 minutes. Component (A), component (B), optionally component (C), and optionally component (D) of the present invention can be mixed with water in advance and used as kneading water, or can be added to cement milk after producing cement milk. It is preferable to use In this manufacturing method, the (A) component, (B) component, optionally the (C) component, optionally the (D) component, clay mineral, soil, water, and hydraulic powder are the same as those described in the soil cement of the present invention. It can be used to satisfy quantitative relationships.
The present invention provides a soil improvement slurry containing hydraulic powder, water, and the additive of the present invention. That is, a slurry for ground improvement containing hydraulic powder, water, component (A), component (B), optionally component (C), and optionally component (D) is provided.
The present invention also provides a soil improvement slurry containing a hydraulic powder, a clay mineral, water, and the additive of the present invention. That is, a slurry for ground improvement containing hydraulic powder, clay mineral, water, component (A), component (B), optionally component (C), and optionally component (D) is provided.
The (A) component, (B) component, optionally (C) component, and optionally (D) component in these include the above-mentioned (A) component, (B) component, optionally (C) component, and optionally ( D) One or more aspects selected from the aspects of component can be applied. These slurries are suitably used in the method for producing soil cement described above. Moreover, the slurry described below may be the ground improvement slurry of the present invention.

Next, the process of mixing the slurry and soil can be classified based on the stirring and mixing mechanism: (1) a method of stirring the prepared slurry with a mechanical stirring blade while discharging it underground, such as the CDM construction method; (2) A method of sending the prepared slurry into the ground as a high-pressure jet fluid, typified by the injection stirring method, scraping off and stirring the surrounding earth and sand, (3) A multi-shaft auger in the underground wall construction method, such as SMW. Methods such as the vertical stirring horizontal pulling method, such as the TRD method, and the like, which discharge a prepared slurry and stir and mix it with the soil in situ, are included, and soil cement is manufactured by these methods.

As an example of a method for creating soil cement or a ground improvement method, hydraulic powder and clay mineral are preferably mixed in an amount of 50% or more, more preferably 60% or more, and preferably 200% of the mass of the hydraulic powder. Hereinafter, a slurry is prepared by mixing with more preferably 150% or less of kneading water (containing the (A) component, (B) component, optionally the (C) component, and optionally the (D) component of the present invention), An example of a method is to pour and mix this slurry into the ground to be improved in a volume of 0.1 to 1.5 times the volume of the soil to be improved, and then harden it.

In this method, if the amount of kneading water in the slurry is 50% or more of the mass of the hydraulic powder, the viscosity of the obtained slurry will be reduced and pumping will be easy, resulting in good workability. When the mass of the soil is 200% or less, material separation is suppressed, and a decrease in strength and variation in the improved soil are also reduced.

In addition, in this method, if the amount of slurry applied is 0.1 times or more the volume of the soil to be improved, the slurry and the soil to be improved will be properly mixed and the quality will be good.

Furthermore, in the method of fluidizing excavated soil and backfilling, the amount of mixing of the hydraulic powder of the present invention and kneading water, and the amount of mixing of slurry and soil to be improved can be carried out in the same manner as described above.

The following were used as component (A) and component (B).

<(A) component>
・Alkyl polyglycoside: 8 to 16 carbon atoms in the alkyl chain, average number of carbon atoms in the alkyl chain 10, degree of sugar condensation 1.1, higher alcohol adduct of glucose

<(B) component>
・Coconut oil fatty acid methylethanolamide: Fatty acid methylethanolamide with a fatty acid carbon number of 8 to 18, HLB3.3
・Polyoxyethylene (1) lauryl ether: Average number of added moles of oxyethylene group is 1, the number in parentheses is the average number of added moles of ethylene oxide, HLB5.2
・Polyoxyethylene (2) laurylamine: average number of added moles of oxyethylene group 2, HLB 6.3

Preparation of soil cement First, cement milk was prepared according to the following procedure. Prepare an additive aqueous solution by mixing components (A) and (B) in Table 1 with water, mix it with cement in a 500ml plastic cup (500ml disposable cup, Nikko Hansen Co., Ltd.), and mix it with a hand mixer. Cement milk was prepared by kneading the mixture for 1 minute.
Tap water was used for preparing the additive aqueous solution. As the cement, ordinary Portland cement (manufactured by Taiheiyo Cement Co., Ltd.) was used. Cement and additive aqueous solution were used such that the mass ratio of additive aqueous solution/cement was 60% by mass. The aqueous additive solution/cement mass ratio substantially corresponds to the water/cement ratio (W/C).
Component (A) and component (B) were used in amounts as shown in Table 1 relative to 100 parts by mass of the hydraulic powder.
Thereafter, clay (Kasaoka Clay) as soil and cement milk were put into another 500 ml plastic cup and stirred for 30 seconds using a hand mixer to prepare soil cement.
The clay was used in an amount as shown in Table 1 based on 100 parts by mass of the hydraulic powder.

Measurement of Set Time 20 g of each of the prepared soil cements shown in Table 1 was placed in a constant temperature calorimeter (TAM Air, manufactured by TA Instrument), and changes in the calorific value of hydration over time were measured at a constant temperature of 20°C. The time point when the calorific value reached the maximum value was defined as an index of setting time, and the setting time of each soil cement was measured. The results are shown in Table 1.

(3) Evaluation of the amount of adiabatic temperature rise due to heat generation from hydration of soil cement Each prepared soil cement was filled into a 1L polypropylene disposable cup, and after inserting a thermocouple into the center of the soil cement, the cup was It was loaded into a Dewar bottle and sealed with a cork. The Dewar bottle was placed in a styrofoam container (thickness 140 mm) filled with polystyrene foam beads, and temperature changes in the mortar were measured over time using a data logger. A schematic diagram of this measurement method is shown in FIG.
The amount of temperature rise from the temperature of the hydraulic powder when it comes into contact with water until it reaches the maximum temperature was defined as the amount of adiabatic temperature rise. The results are shown in Table 1. Table 1 also shows the difference in the amount of adiabatic temperature rise between each Example and Comparative Example, with Comparative Example 1 as a standard. It can be said that the larger the difference in the amount of adiabatic temperature rise is a positive number, the more excellent the suppression of temperature rise due to heat generation from hydration of the hydraulic powder is.

Claims (8)

A soil cement containing the following component (A), the following component (B), hydraulic powder, soil containing clay minerals, and water,
The total content of components (A) and (B) is 0.05 parts by mass or more and 4 parts by mass or less based on 100 parts by mass of the hydraulic powder, and the content of clay mineral is 100 parts by mass of the hydraulic powder. soil cement.
(A) Component: At least one type of (poly)glycoside having an alkyl group having 8 to 20 carbon atoms or an alkenyl group having 8 to 20 carbon atoms and having a degree of sugar condensation of 1 to 5. (B) Component : A nonionic surfactant represented by the following general formula (B11), a nonionic surfactant represented by the following general formula (B12), and a nonionic surfactant represented by the following general formula (B13). at least one nonionic surfactant selected from the group consisting of nonionic surfactants with an HLB value of 2 or more and 11 or less;

[During the ceremony,
R ¹¹ , R ³¹ : each from an alkyl group having 8 to 22 carbon atoms, an alkenyl group having 8 to 22 carbon atoms, an aralkyl group having 8 to 22 carbon atoms, and a substituted aryl group having 8 to 22 carbon atoms; Selected group R ²¹ : selected from an alkyl group having 7 to 21 carbon atoms, an alkenyl group having 7 to 21 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, and a substituted aryl group having 7 to 21 carbon atoms. Group R ²² : Alkylene group having 2 to 4 carbon atoms X ¹ : Group selected from an alkyl group having 1 to 3 carbon atoms, and a group represented by -R ²² -OH R ³² , R ³³ : Each is hydrogen Atom or alkyl group having 1 to 3 carbon atoms AO: Alkyleneoxy group having 2 to 4 carbon atoms p1: Number from 3 to 100 q1, r1: Each number is 0 or more, and the sum of q1 and r1 is , a number from 0.5 to 100. ] The soil cement according to claim 1, wherein the mass ratio (A)/(B) of the content of the component (A) to the content of the component (B) is 0.05 or more and 2.0 or less. Claim 1, wherein the mass ratio between the total content of components (A) and (B) and the content of clay minerals (clay minerals/((A)+(B))) is 2 or more and 100 or less. Or the soil cement described in 2. A method for producing soil cement in which the following component (A), the following component (B), hydraulic powder, soil containing clay minerals, and water are mixed,
The total amount of components (A) and (B) mixed is 0.05 parts by mass or more and 4 parts by mass or less per 100 parts by mass of the hydraulic powder, and the mixed amount of the clay mineral is 100 parts by mass of the hydraulic powder. A method for producing soil cement, wherein the amount is 1 part by mass or more and 20 parts by mass or less.
(A) Component: At least one type of (poly)glycoside having an alkyl group having 8 to 20 carbon atoms or an alkenyl group having 8 to 20 carbon atoms and having a degree of sugar condensation of 1 to 5. (B) Component : A nonionic surfactant represented by the following general formula (B11), a nonionic surfactant represented by the following general formula (B12), and a nonionic surfactant represented by the following general formula (B13). at least one nonionic surfactant selected from the group consisting of nonionic surfactants with an HLB value of 2 or more and 11 or less;

[During the ceremony,
R ¹¹ , R ³¹ : each from an alkyl group having 8 to 22 carbon atoms, an alkenyl group having 8 to 22 carbon atoms, an aralkyl group having 8 to 22 carbon atoms, and a substituted aryl group having 8 to 22 carbon atoms; Selected group R ²¹ : selected from an alkyl group having 7 to 21 carbon atoms, an alkenyl group having 7 to 21 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, and a substituted aryl group having 7 to 21 carbon atoms. Group R ²² : Alkylene group having 2 to 4 carbon atoms X ¹ : Group selected from an alkyl group having 1 to 3 carbon atoms, and a group represented by -R ²² -OH R ³² , R ³³ : Each is hydrogen Atom or alkyl group having 1 to 3 carbon atoms AO: Alkyleneoxy group having 2 to 4 carbon atoms p1: Number from 3 to 100 q1, r1: Each number is 0 or more, and the sum of q1 and r1 is , a number from 0.5 to 100. ] The soil cement according to claim 4, wherein a slurry is prepared by mixing the component (A), the component (B), a hydraulic powder, water, and a clay mineral, and then the slurry and soil are mixed. manufacturing method. A ground improvement body containing the following (A) component, the following (B) component, hydraulic powder, water, and soil containing clay minerals,
The total content of components (A) and (B) is 0.05 parts by mass or more and 4 parts by mass or less based on 100 parts by mass of the hydraulic powder, and the content of clay mineral is 100 parts by mass of the hydraulic powder. The soil improvement material is 1 part by mass or more and 20 parts by mass or less.
(A) Component: At least one type of (poly)glycoside having an alkyl group having 8 to 20 carbon atoms or an alkenyl group having 8 to 20 carbon atoms and having a degree of sugar condensation of 1 to 5. (B) Component : A nonionic surfactant represented by the following general formula (B11), a nonionic surfactant represented by the following general formula (B12), and a nonionic surfactant represented by the following general formula (B13). at least one nonionic surfactant selected from the group consisting of nonionic surfactants with an HLB value of 2 or more and 11 or less;

[During the ceremony,
R ¹¹ , R ³¹ : each from an alkyl group having 8 to 22 carbon atoms, an alkenyl group having 8 to 22 carbon atoms, an aralkyl group having 8 to 22 carbon atoms, and a substituted aryl group having 8 to 22 carbon atoms; Selected group R ²¹ : selected from an alkyl group having 7 to 21 carbon atoms, an alkenyl group having 7 to 21 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, and a substituted aryl group having 7 to 21 carbon atoms. Group R ²² : Alkylene group having 2 to 4 carbon atoms X ¹ : Group selected from an alkyl group having 1 to 3 carbon atoms, and a group represented by -R ²² -OH R ³² , R ³³ : Each is hydrogen Atom or alkyl group having 1 to 3 carbon atoms AO: Alkyleneoxy group having 2 to 4 carbon atoms p1: Number from 3 to 100 q1, r1: Each number is 0 or more, and the sum of q1 and r1 is , a number from 0.5 to 100. ] A ground improvement method in which the following (A) component, the following (B) component, hydraulic powder, soil containing clay minerals, and water are mixed,
The total amount of components (A) and (B) mixed is 0.05 parts by mass or more and 4 parts by mass or less per 100 parts by mass of the hydraulic powder, and the mixed amount of the clay mineral is 100 parts by mass of the hydraulic powder. A soil improvement method in which the amount is 1 part by mass or more and 20 parts by mass or less.
(A) Component: At least one type of (poly)glycoside having an alkyl group having 8 to 20 carbon atoms or an alkenyl group having 8 to 20 carbon atoms and having a degree of sugar condensation of 1 to 5. (B) Component : A nonionic surfactant represented by the following general formula (B11), a nonionic surfactant represented by the following general formula (B12), and a nonionic surfactant represented by the following general formula (B13). at least one nonionic surfactant selected from the group consisting of nonionic surfactants with an HLB value of 2 or more and 11 or less;

[During the ceremony,
R ¹¹ , R ³¹ : each from an alkyl group having 8 to 22 carbon atoms, an alkenyl group having 8 to 22 carbon atoms, an aralkyl group having 8 to 22 carbon atoms, and a substituted aryl group having 8 to 22 carbon atoms; Selected group R ²¹ : selected from an alkyl group having 7 to 21 carbon atoms, an alkenyl group having 7 to 21 carbon atoms, an aralkyl group having 7 to 21 carbon atoms, and a substituted aryl group having 7 to 21 carbon atoms. Group R ²² : Alkylene group having 2 to 4 carbon atoms X ¹ : Group selected from an alkyl group having 1 to 3 carbon atoms, and a group represented by -R ²² -OH R ³² , R ³³ : Each is hydrogen Atom or alkyl group having 1 to 3 carbon atoms AO: Alkyleneoxy group having 2 to 4 carbon atoms p1: Number from 3 to 100 q1, r1: Each number is 0 or more, and the sum of q1 and r1 is , a number from 0.5 to 100. ] The method of preparing the ground according to claim 7, wherein a slurry is prepared by mixing the component (A), the component (B), hydraulic powder, water, and clay mineral, and then the slurry and soil are mixed. Improved construction method.