Cementing material for curing high-water-content silt soft soil as well as preparation method and application of cementing material

Abstract

The invention relates to the technical field of building materials, in particular to a cementing material for curing high-water-content silt soft soil as well as a preparation method and application thereof, and the cementing material comprises the following components in percentage by weight: 15-40% of Portland cement, 20-45% of mineral powder, 5-20% of bentonite, 10-30% of zeolite powder, 2-10% of metakaolin and 0.5-6% of an exciting agent. The cementing material is simple in component and excellent in curing performance on high-water-content silt soft soil, the Portland cement, the mineral powder, the bentonite, the zeolite powder, the metakaolin and the excitation powder are mixed and compounded in proportion, the obtained cementing material is good in curing effect on the high-water-content silt soft soil, uniform curing can be achieved, and the curing effect is good. The cured sludge soft soil is high in strength and good in impermeability, the strength development of the high-water-content sludge soft soil is promoted, and the curing agent is suitable for curing the sludge soft soil with the water content higher than 60%.

Description

Technical Field

[0001] The invention relates to the technical field of building materials, and in particular to a cementing material for solidifying high-water-content silt soft soil, and a preparation method and application thereof. Background Art

[0002] In areas such as the Pearl River Delta where soft foundations are widely distributed, improper soft foundation treatment will affect the safety and stability of the superstructure. Among traditional treatment methods, cement reinforcement is widely used for soft foundation reinforcement due to its advantages such as convenient construction. However, for high-water content silty soft soil, cement reinforcement often has low curing strength and slow strength development, and it is still difficult to achieve a good reinforcement effect at a higher dosage. Therefore, the development of a binder for the solidification of high-water content silty soft soil is of great significance for improving the reinforcement strength of high-water content silty soft soil, improving the engineering quality of soft foundation reinforcement, and ensuring the safety, stability and durability of the superstructure.

[0003] Chinese patent application CN117645455A discloses a dredged sludge solidification material and a pipeline solidification and filling method, wherein the solidification material is composed of sea sand, drag reduction material, erosion-resistant hydraulic cementing material, dispersing material, early strength material and precipitation material, wherein the erosion-resistant hydraulic cementing material is composed of cement and mineral admixture, the precipitation material can be one or more of zeolite, calcium-based bentonite, sepiolite, and diatomaceous earth, the sea sand large particle material provides skeleton support for the later solidification reaction, improves the solidification strength and later foundation settlement, and the erosion-resistant hydraulic cementing material and precipitation material improve the erosion resistance of the dredged sludge after solidification, and reduce the cracking and expansion of the spinous process soil after solidification. However, its composition raw materials are relatively large, and the infinite side compressive strength needs to be further improved. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a bonding material for solidifying high-water content silt soft soil and its preparation method and application. The bonding material is suitable for solidifying silt soft soil with a water content higher than 60%, and has good strength and anti-seepage performance.

[0005] In order to solve the above technical problems, the first aspect of the present invention provides a binder material for solidifying high-water content silt soft soil, the components of the binder material including, by weight percentage: 15-40% silicate cement, 20-45% mineral powder, 5-20% bentonite, 10-30% zeolite powder, 2-10% kaolin and 0.5-6% activator.

[0006] As an improvement of the above scheme, the high-water content silt soft soil is silt soft soil with a water content of 60-150% and an organic matter content of 5-10%.

[0007] As an improvement of the above solution, the activator is sodium sulfate.

[0008] As an improvement of the above scheme, the fineness of the zeolite powder is 80μm square hole sieve residue is less than or equal to 10%, the ammonium absorption value is greater than or equal to 100mmol / 100g, and the 28-day compressive strength ratio of the zeolite powder cement mortar is greater than or equal to 70%.

[0009] As an improvement of the above solution, the pore size of the zeolite powder satisfies the following relationship:

[0010] (D10+D50) / D90=1.0~1.6;

[0011] D90 / S=2.6~3.5;

[0012] Wherein, D10 is the pore size corresponding to when the cumulative distribution of zeolite powder accounts for 10%, D50 is the pore size corresponding to when the cumulative distribution of zeolite powder accounts for 50%, and D90 is the pore size corresponding to when the cumulative distribution of zeolite powder accounts for 90%, and the unit is nm;

[0013] S is the specific surface area, and its unit is m 2 / g.

[0014] As an improvement of the above scheme, the chemical composition of the bentonite meets the definition of the following relationship:

[0015]

[0016] Among them, k1 is a constant, and its value range is 1.05~1.1, and k2 is a constant, and its value range is 1.3~1.5;

[0017] n(Na + ) is the exchangeable Na in bentonite + Molar content; n(Ca 2+ ) is the exchangeable Ca in bentonite 2+ Molar content; w(Na 2 O) is the Na measured in bentonite 2 O mass fraction; w(K 2 O) is the K measured in bentonite 2 O mass fraction; w(CaO) is the mass fraction of CaO measured in bentonite; w(MgO) is the mass fraction of MgO measured in bentonite;

[0018] The fineness of the bentonite is 200-600 meshes.

[0019] As an improvement of the above solution, the weight ratio of the zeolite powder to the bentonite is 1:(0.3-0.7).

[0020] As an improvement of the above scheme, the metakaolin is calcined metakaolin, and the fineness of the metakaolin is 200-500 mesh;

[0021] The activity index of the mineral powder reaches more than 95% at 28 days;

[0022] The strength grade of the silicate cement is not less than 42.5.

[0023] The second aspect of the present invention provides a method for preparing the cementing material for solidifying high-water content silt soft soil, the steps comprising:

[0024] (1) Weighing silicate cement, mineral powder, bentonite, zeolite powder, metakaolin and activator according to weight for use;

[0025] (2) Mix silicate cement, mineral powder, bentonite, zeolite powder, metakaolin and activator evenly to obtain the product.

[0026] The third aspect of the present invention provides an application of a cementing material for high-water content silt soft soil solidification in high-water content silt soft soil solidification, and the use method thereof is as follows:

[0027] The adhesive material is mixed with water to form an adhesive material slurry, and then evenly stirred with high-water content silt soft soil, wherein the mixing ratio of the adhesive material to water in the adhesive material slurry is 1: (0.6-0.8).

[0028] The implementation of the present invention has the following beneficial effects:

[0029] The composition of the cementing material in the present invention is simple, and the curing performance of the high-water-content sludge soft soil is excellent. Portland cement, mineral powder, bentonite, zeolite powder, metakaolin and activating powder are mixed and compounded in proportion, and the obtained cementing material has a good curing effect on the high-water-content sludge soft soil, can achieve uniform curing, and the solidified sludge soft soil has high strength and good anti-permeability, and promotes the strength development of the high-water-content sludge soft soil.

[0030] Portland cement can first react quickly with water in high-water-content sludge to form a gel-like substance. The addition of mineral powder, metakaolin, and activator can help improve the slurry fluidity and workability of sludge soft soil solidification cementing materials, improve the uniformity of mixing the solidification materials and sludge soft soil, and improve the strength of solidified sludge soil. The addition of bentonite and zeolite powder can reduce the attenuation of the hydration strength of the solidification material due to excessive water content, thereby increasing the solidification strength. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail with specific embodiments below.

[0032] To solve the above problems, the first aspect of the present invention provides a binder material for solidifying high-water content silt soft soil, the components of the binder material include, by weight percentage: 15-40% silicate cement, 20-45% mineral powder, 5-20% bentonite, 10-30% zeolite powder, 2-10% kaolin and 0.5-6% activator.

[0033] In the present invention, silicate cement, mineral powder, bentonite, zeolite powder, metakaolin and activating powder are mixed and compounded in proportion, and the obtained cementing material has a good curing effect on high-water content sludge soft soil, can achieve uniform curing, and the solidified sludge soft soil has high strength and good anti-permeability, and promotes the strength development of high-water content sludge soft soil. Among them, silicate cement can first react quickly with water in high-water content sludge to form a gel-like substance, and the addition of mineral powder, metakaolin and activating agent can help improve the slurry fluidity and workability of the sludge soft soil curing cementing material, improve the uniformity of mixing the curing material and the sludge soft soil, and at the same time improve the strength of the cured sludge soil, and the addition of bentonite and zeolite powder can reduce the attenuation effect of the hydration strength of the curing material due to excessive water content, thereby increasing the curing strength.

[0034] The soft soil in the Pearl River Delta and other regions has the characteristics of high water content, low strength, poor permeability, high compressibility, etc., which further affects the stability of the soft foundation, the consolidation rate, etc., and the organic matter in the silt will inhibit the hydration of cement. In the present invention, the high-water content silt soft soil is a silt soft soil with a water content higher than 60%, and further refers to a silt soft soil with a water content of 60-150% and an organic matter content of 5-10%.

[0035] Preferably, the strength grade of the silicate cement is not less than 42.5, and the optional silicate cements have strength grades of 42.5, 42.5R, 52.5, 52.5R, 62.5, and 62.5R, so as to ensure that the silicate cement contains a lot of tricalcium silicate to promote the hydration reaction and obtain a high-strength solidified soft base. Specifically, the added weight percentage of the silicate cement is exemplarily 15%, 20%, 25%, 30%, 35%, and 40%, but is not limited thereto.

[0036] Furthermore, the mineral powder and metakaolin can be used as mineral admixtures, which have high volcanic ash activity and react to generate a large amount of CSH gel in an alkaline environment, thereby forming strength and further improving the strength after curing. Among them, the activity index of the mineral powder reaches more than 95% at 28 days, that is, the selected mineral powder is not lower than S95 grade. The metakaolin is calcined metakaolin, and its active ingredients are more easily reacted with Ca(OH) precipitated during cement hydration. 2Reaction to generate a product with gel properties, reducing the initial and final setting time of cement paste. The fineness of the metakaolin is 200-500 mesh, with a suitable specific surface area, which is conducive to more effective participation in the hydration reaction, thereby improving the strength of the solidified material. S95 grade mineral powder, calcined metakaolin with a fineness of 200-500 mesh and an activator can cooperate with each other to improve the slurry fluidity and workability of the silt soft soil solidification cementing material, and improve the uniformity of mixing the solidified material and the silt soft soil. Specifically, the added weight of the mineral powder is exemplified as 20%, 25%, 30%, 35%, 40%, 45%, but not limited thereto; the added weight percentage of the metakaolin is exemplified as 2 parts, 5 parts, 7 parts, 9 parts, 10 parts, but not limited thereto.

[0037] In some specific and preferred embodiments, the activator is sodium sulfate. The addition of sodium sulfate can activate the activity of mineral powder, metakaolin, and zeolite powder. Sulfate ions react with calcium phase and aluminum phase components to generate a large amount of AFt, thereby improving the hydration strength of the cementitious material. In addition, sodium sulfate can improve the fluidity and permeability of the slurry, enhance the uniformity of mixing the cementitious material with the soft soil particles, and make the hydration product form a dense network structure to wrap the soft soil particles therein, thereby improving the strength of the solidified silt soil. It can work synergistically with silicate cement, mineral powder, bentonite, zeolite powder, and metakaolin in the system to obtain a cementitious material with excellent solidification strength suitable for high-water content silt soft soil. Specifically, the added weight percentage of the activator is 0.5%, 1%, 2%, 3%, 4%, 5%, and 6%, but is not limited thereto. More preferably, the added weight percentage of the activator is 2 to 4%.

[0038] The bentonite in the present invention can be combined with Ca(OH) 2 The reaction generates CSH gel and CAH, etc., forming strength and strengthening the soil; secondly, bentonite can absorb excess free water in high-water content silt soil, reduce the attenuation of hydration strength of cementitious materials due to excessive water content, and expand when it absorbs water, and the hydration products squeeze and fill the pores of the soil, enhancing the density of the soil skeleton; finally, the active oxides contained in bentonite can catalyze the hydration of various cementitious materials, accelerate the production of hydration products, improve early strength, and promote the strength development of high-water content sludge soft soil. In addition, zeolite powder belongs to volcanic ash material, has volcanic ash effect, can hydrate and generate CSH gel in an alkaline environment, and the addition of zeolite powder is beneficial to improve density and strength. There are a large number of nano-scale pores inside zeolite powder, which can absorb excess free water in silt soil and improve the strength of solidified silt soil. However, if the water absorption of the cementitious material is too high, it will inhibit the hydration reaction of cement, prolong the setting and curing time of cement, and weaken the strength of the soft foundation.

[0039] Preferably, the fineness of the zeolite powder is 80 μm square hole sieve residue is less than or equal to 10%, the ammonium absorption value is greater than or equal to 100 mmol / 100 g, and the 28-day compressive strength ratio of the zeolite powder cement mortar is greater than or equal to 70%. That is, the zeolite powder can be selected from grade II zeolite powder, which has good dispersibility, high reaction activity, strong ammonium absorption ability, and can more effectively react with Ca(OH) in cement. 2 The reaction helps to further improve the strength and impermeability of the solidified soil, and can participate in the hydration reaction faster, shorten the gel time, improve the strength development of the solidified soil, and improve the durability of the solidified soil.

[0040] Furthermore, the pore size of the zeolite powder satisfies the following relationship: (D10+D50) / D90=1.0~1.6; D90 / S=2.6~3.5; wherein D10 is the corresponding pore size when the cumulative distribution of the zeolite powder accounts for 10%, D50 is the corresponding pore size when the cumulative distribution of the zeolite powder accounts for 50%, and D90 is the corresponding pore size when the cumulative distribution of the zeolite powder accounts for 90%, and the unit is nm, and the pore size distribution is obtained by BET test; S is the specific surface area, and the unit is m 2 / g, obtained through testing by a multi-station fully automatic specific surface area and pore analyzer.

[0041] By controlling the particle size distribution of zeolite powder, it is possible to provide zeolite powder with appropriate water absorption and water retention, while controlling D90 / specific surface area = (2.6-3.5) (nm / m 2 ·g -1 ), so that the zeolite powder has a certain porosity, so that the pores with suitable particle size are easy to store more water and are easy to release under specific conditions. When the moisture content inside the cement-based material is reduced to a certain level, the stored water can be released from the pores to promote the further progress of the hydration reaction, which can not only enhance the curing strength of the soft base and promote the early strength development of the soft base, but also further reduce the effect of the addition of zeolite powder particles on the fluidity of the system. In addition, it can also delay the self-drying of the material and play a role in reducing shrinkage.

[0042] The chemical composition of the bentonite is defined by the following relationship:

[0043]

[0044] Among them, k1 is a constant, and its value range is 1.05~1.1, and k2 is a constant, and its value range is 1.3~1.5;

[0045] n(Na + ) is the exchangeable Na in bentonite + Molar content; n(Ca 2+ ) is the exchangeable Ca in bentonite 2+Molar content; exchangeable Na + , Ca 2+ Molar content = measured molar concentration * mass of bentonite, wherein the molar concentration can be obtained by quantitative analysis through EDTA-acetate exchange method.

[0046] w(Na 2 O) is the Na measured in bentonite 2 O mass fraction; w(K 2 O) is the K measured in bentonite 2 O mass fraction; w(CaO) is the mass fraction of CaO measured in bentonite; w(MgO) is the mass fraction of MgO measured in bentonite; w(Na 2 O), w(K 2 O), w(CaO), w(MgO) are obtained by titration.

[0047] When the chemical composition of bentonite meets the definition of the above relationship, it has a suitable cation exchange capacity and can accommodate more pore water. When used in combination with the zeolite powder, the fluidity of the system can be improved, and it can be used as a part of the cementitious material to form strength through hydration. Moreover, when used in high-water content silt soft soil with a water content of 60-150%, it can adsorb most of the free water molecules, reduce the attenuation effect of excessive water content on the hydration strength of the solidified material, shorten the initial setting time, and at the same time ensure that sufficient hydration reaction occurs in the silt soft soil with a water content of 60-150%. In addition, sufficient water can be stored in the system and slowly released in the later stage to promote the hydration reaction of the soft foundation, shorten the final setting time, play a maintenance and shrinkage prevention effect, and is beneficial to improving the strength and anti-seepage performance of the solidified silt soil.

[0048] More preferably, the fineness of the bentonite is 200-600 mesh, and the weight ratio of the zeolite powder to the bentonite is 1:(0.3-0.7). Controlling the weight ratio of the zeolite powder to the bentonite can regulate the fluidity and pore structure of the cementing material, thereby simultaneously improving the unconfined compressive strength and impermeability of the solidified silt soil. Specifically, the weight ratio of the zeolite powder to the bentonite is 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, but is not limited thereto.

[0049] Correspondingly, the present invention also discloses a method for preparing the cementing material for solidifying high-water content silt soft soil, the steps comprising:

[0050] (1) Weighing silicate cement, mineral powder, bentonite, zeolite powder, metakaolin and activator according to weight for use;

[0051] (2) Mix silicate cement, mineral powder, bentonite, zeolite powder, metakaolin and activator evenly to obtain the product.

[0052] Preferably, in step (2), the stirring rate during the uniform mixing is 40 to 60 rpm, and the stirring time is not less than 180 seconds until the mixture is uniformly mixed, and then the mixture can be bagged, sealed or canned.

[0053] Correspondingly, the present invention also discloses an application of the cementing material for high-water content silt soft soil solidification in high-water content silt soft soil solidification, and the use method thereof is as follows:

[0054] The adhesive material is mixed with water to form an adhesive material slurry, and then evenly stirred with high-water content silt soft soil, wherein the mixing ratio of the adhesive material to water in the adhesive material slurry is 1: (0.6-0.8).

[0055] Furthermore, the added mass of the adhesive material is 10-20% of the mass of the high-water content silt soft soil.

[0056] Preferably, a strong stirring device may be used to stir and mix the cementitious material slurry and the soft soil evenly.

[0057] The present invention will be further described below with specific embodiments:

[0058] Example 1

[0059] This embodiment provides a cementing material for solidifying high-water content silt soft soil, and its components are as follows by weight:

[0060] 40 parts of 42.5R silicate cement, 30 parts of S95 grade mineral powder, 8 parts of sodium-based bentonite, 15 parts of grade II zeolite powder, 5 parts of 250 mesh calcined metakaolin powder and 2 parts of activator (sodium sulfate), a total of 100 parts.

[0061] The preparation method is as follows: 42.5R silicate cement, S95 grade mineral powder, sodium-based bentonite (fineness is 400 meshes), grade II zeolite powder, 250 mesh calcined metakaolin and sodium sulfate are weighed according to weight parts, and then mixed evenly to obtain the product.

[0062] Example 2

[0063] This embodiment provides a cementing material for solidifying high-water content silt soft soil, and its components are as follows by weight:

[0064] 40 parts of 42.5R Portland cement, 30 parts of S95 grade mineral powder, 8 parts of bentonite, 15 parts of zeolite powder, 5 parts of 250 mesh calcined metakaolin powder and 2 parts of activator (sodium sulfate), a total of 100 parts;

[0065] Among them, in the zeolite powder, D10 is 15 μm, D50 is 40 μm, D90 is 50 μm, (D10+D50) / D90=1.1; the specific surface area is 15.2m 2 / g, D90 / specific surface area = 3.3;

[0066] Calculated based on 1kg bentonite (fineness 400 mesh), in the chemical composition, n(Na + )=0.25mol, k1=1.08, n(Ca 2 + )=0.14mol, k2=1.38, w(Na 2 O)=0.25%,w(Ka 2 O)=0.14%, w(CaO)=0.26%, w(MgO)=4.1%,

[0067]

[0068] The preparation method is the same as Example 1.

[0069] Example 3

[0070] This embodiment provides a cementing material for solidifying high-water content silt soft soil, and its components are as follows by weight:

[0071] 40 parts of 42.5R Portland cement, 30 parts of S95 grade mineral powder, 8 parts of bentonite, 15 parts of zeolite powder, 5 parts of 250 mesh calcined metakaolin powder and 2 parts of activator (sodium sulfate), a total of 100 parts;

[0072] Among them, in the zeolite powder, D10 is 15 μm, D50 is 50 μm, D90 is 70 μm, (D10+D50) / D90=0.9; the specific surface area is 14.3m 2 / g, D90 / specific surface area = 4.9;

[0073] Calculated based on 1kg bentonite (fineness 400 mesh), n(Na + )=0.25mol, k1=1.08, n(Ca 2+ )=0.14mol, k2=1.38, w(Na 2 O)=0.25%,w(Ka 2 O)=0.14%, w(CaO)=0.26%, w(MgO)=4.1%,

[0074]

[0075] The preparation method is the same as Example 1.

[0076] Example 4

[0077] This embodiment provides a cementing material for solidifying high-water content silt soft soil, and its components are as follows by weight:

[0078] 40 parts of 42.5R Portland cement, 30 parts of S95 grade mineral powder, 8 parts of bentonite, 15 parts of zeolite powder, 5 parts of 250 mesh calcined metakaolin powder and 2 parts of activator (sodium sulfate), a total of 100 parts;

[0079] Among them, in the zeolite powder, D10 is 15 μm, D50 is 40 μm, D90 is 50 μm, (D10+D50) / D90=1.1; the specific surface area is 15.2m 2 / g, D90 / specific surface area = 3.3;

[0080] Calculated based on 1kg bentonite (fineness 400 mesh), n(Na + )=0.2mol,k1=1.1,n(Ca 2+ )=0.15mol, k2=1.38, w(Na 2 O)=0.21%,w(Ka 2 O)=0.16%, w(CaO)=0.27%, w(MgO)=4.1%,

[0081]

[0082] The preparation method is the same as Example 1.

[0083] Example 5

[0084] This embodiment provides a cementing material for solidifying high-water content silt soft soil, and its components are as follows by weight:

[0085] 25 parts of 42.5R silicate cement, 40 parts of S95 grade mineral powder, 8 parts of sodium-based bentonite, 15 parts of grade II zeolite powder, 8 parts of 250 mesh calcined metakaolin powder and 4 parts of activator (sodium sulfate), a total of 100 parts.

[0086] The preparation method is the same as Example 1.

[0087] Comparative Example 1

[0088] This comparative example provides a cementing material for solidifying high-water content silt soft soil, and its components are calculated by weight:

[0089] 42 parts of 42.5R silicate cement, 30 parts of S95 grade mineral powder, 8 parts of sodium-based bentonite, 15 parts of grade II zeolite powder and 5 parts of 250 mesh calcined metakaolin powder, a total of 100 parts.

[0090] Comparative Example 2

[0091] This comparative example provides a bonding material, the ingredients of which are as follows by weight: 100 parts of 42.5R Portland cement.

[0092] Performance Testing

[0093] The binder materials in Examples 1 to 5 and Comparative Examples 1 to 2 were stirred and tested for relevant properties according to the method specified in "Soft Soil Solidifier" (CJ / T 526-2018), and the permeability coefficient of the solidified silt soil was tested according to the method specified in "Standard for Geotechnical Test Methods" (GB / T50123-2019). Among them, the high-water content silt soft soil sample was made of silty soil drilled 5 to 10 m underground in a project in Foshan, with a water content of 65%, an organic matter content of 7.1%, and a water-cement ratio of 0.7 to obtain a pure slurry. When forming the solidified silt soil test blocks, the amount of binder added was 15% of the mass of the silt soil.

[0094] The specific results are shown in Table 1 below.

[0095] Table 1 Performance test results of embodiments and comparative examples

[0096]

[0097]

[0098] By analyzing the experimental data in Table 1, it can be seen from the comparison between Example 1 and Comparative Example 1 that the addition of the activator plays a vital role in improving the fluidity of the cementitious material slurry, the unconfined compressive strength and the impermeability of the solidified silt soil. By comparing Examples 1 to 5 with Comparative Example 2, it can be seen that the cementitious material for solidifying high-water content silt soft soil provided by the present invention has a synergistic effect under specific components and specific proportions to make the fluidity of the pure slurry excellent, and the solidification effect on the solidified soil is much better than that of traditional cement.

[0099] Further, by comparing Example 1 with Example 2, it can be seen that (D10+D50) / D90=1.0-1.6, D90 / specific surface area=(2.6-3.5)(nm / m 2 ·g -1 ) and montmorillonite whose chemical composition satisfies the relationship defined by the formula are beneficial to improving the fluidity of the cementitious material slurry and the unconfined compressive strength and impermeability of the solidified silt soil; by comparing Example 2 with Example 3 and Example 4, it can be seen that changing the parameters of the zeolite powder or increasing the content of montmorillonite in the bentonite will slightly reduce the fluidity of the cementitious material slurry and shorten the setting time, but reduce the unconfined compressive strength and impermeability of the solidified silt soil; by comparing Example 1 with Example 5, it can be seen that increasing the dosage of mineral powder, kaolin and activator at the same time can greatly improve the fluidity of the cementitious material slurry, the unconfined compressive strength and impermeability of the solidified silt soil.

[0100] It can be seen from the test results in the table that the binder material used for solidifying high-water content silt soft soil in this embodiment has good net slurry fluidity, is easy to construct, and has excellent strength and impermeability of solidified silt soft soil, and is suitable for solidifying high-water content and high-organic matter content silt soft soil.

[0101] The above disclosure is only a preferred embodiment of the present invention, which certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A cementing material for solidifying high-water content silt soft soil, characterized in that: The components of the cementing material include, by weight percentage, 15-40% of silicate cement, 20-45% of mineral powder, 5-20% of bentonite, 10-30% of zeolite powder, 2-10% of metakaolin and 0.5-6% of activator.

2. The cementing material for solidifying high-water content silt soft soil according to claim 1, characterized in that: The high-water content silt soft soil is silt soft soil with a water content of 60-150% and an organic matter content of 5-10%.

3. The cementing material for solidifying high-water content silt soft soil according to claim 1, characterized in that: The activator is sodium sulfate.

4. The cementing material for solidifying high-water content silt soft soil according to claim 1, characterized in that: The fineness of the zeolite powder is that the residue on a 80 μm square mesh sieve is less than or equal to 10%, the ammonium absorption value is greater than or equal to 100 mmol / 100 g, and the 28-day compressive strength ratio of the zeolite powder cement mortar is greater than or equal to 70%.

5. The cementing material for solidifying high-water content silt soft soil according to claim 4, characterized in that: The pore size of the zeolite powder satisfies the following relationship: (D10+D50) / D90=1.0~1.6; D90 / S=2.6~3.5; Wherein, D10 is the pore size corresponding to when the cumulative distribution of zeolite powder accounts for 10%, D50 is the pore size corresponding to when the cumulative distribution of zeolite powder accounts for 50%, and D90 is the pore size corresponding to when the cumulative distribution of zeolite powder accounts for 90%, and the unit is nm; S is the specific surface area, and its unit is m 2 / g.

6. The cementing material for solidifying high-water content silt soft soil according to claim 1 or 5, characterized in that: The chemical composition of the bentonite is defined by the following relationship: Among them, k1 is a constant, and its value range is 1.05~1.1, and k2 is a constant, and its value range is 1.3~1.5; n(Na + ) is the exchangeable Na in bentonite + Molar content; n(Ca 2+ ) is the exchangeable Ca in bentonite 2+ Molar content; w(Na2O) is the mass fraction of Na2O measured in bentonite; w(K2O) is the mass fraction of K2O measured in bentonite; w(CaO) is the mass fraction of CaO measured in bentonite; w(MgO) is the mass fraction of MgO measured in bentonite; The fineness of the bentonite is 200-600 meshes.

7. The cementing material for solidifying high-water content silt soft soil according to claim 6, characterized in that: The weight ratio of the zeolite powder to the bentonite is 1:(0.3-0.7).

8. The cementing material for solidifying high-water content silt soft soil according to claim 1, characterized in that: The metakaolin is calcined metakaolin, and the fineness of the metakaolin is 200-500 mesh; The activity index of the mineral powder reaches more than 95% at 28 days; The strength grade of the silicate cement is not less than 42.

5.

9. A method for preparing a cementing material for solidifying high-water content silt soft soil according to any one of claims 1 to 8, characterized in that the steps include: (1) Weighing silicate cement, mineral powder, bentonite, zeolite powder, metakaolin and activator according to weight for use; (2) Mix silicate cement, mineral powder, bentonite, zeolite powder, metakaolin and activator evenly to obtain the product.

10. Use of the cementing material for high-water content silt soft soil solidification according to any one of claims 1 to 8 or the cementing material prepared by the preparation method according to claim 9 in high-water content silt soft soil solidification, wherein the use method is: The adhesive material is mixed with water to form an adhesive material slurry, and then evenly stirred with high-water content silt soft soil, wherein the mixing ratio of the adhesive material to water in the adhesive material slurry is 1: (0.6-0.8).

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