Component-based alkali-activated full-size steel slag solidified soil material and preparation method thereof

Abstract

The application provides a kind of based on component regulation alkali-activated full particle size steel slag solidified soil material and preparation method thereof, belongs to building material technical field.The material comprises the following components: clay 100 parts, water 29.3~42.8 parts, cement 3~12 parts, ionic soil solidifying agent 0.016~0.022 parts, steel slag 40~150 parts, steel slag micro powder 0~37.5 parts, blast furnace slag micro powder 37.5~90 parts, sodium silicate solution 4.86~12.6 parts.The application can improve the utilization rate of steel slag solid waste, significantly improve the early bearing capacity, crack resistance and deformation resistance of solidified soil, and make the material suitable for road base, bottom base and other engineering scenarios.The method reduces the use of natural aggregate and cement, which is conducive to the large-scale resource utilization of industrial solid waste such as steel slag, and has good engineering application value and environmental benefits.

Description

Technical Field

[0001] This invention relates to the field of building materials technology, and in particular to a component-controlled alkali-activated full-size steel slag solidified soil material and its preparation method. Background Technology

[0002] Steel slag is a typical byproduct of steel smelting and an important component of industrial solid waste.

[0003] Developing full-size steel slag-stabilized soil is one of the effective ways to achieve efficient utilization of steel slag resources and reduce engineering construction costs. This material mainly utilizes the synergistic effect of ionic soil stabilizers and alkali-activated cementitious systems to integrate steel slag as aggregate and micro-aggregate into the soil stabilization system. Although existing soil stabilization technologies can improve soil properties to some extent, they often face mechanical shortcomings such as slow early strength development, low resilience modulus, and insufficient resistance to deformation, making it difficult to meet the construction requirements of high-standard road base courses.

[0004] In summary, to address the issues of low early bearing capacity and poor deformation resistance in solidified soil, this patent utilizes the ion exchange effect of ionic solidifying agents to disrupt the double-layer structure on the surface of soil particles, reducing the thickness of the bound water film and promoting particle flocculation. Simultaneously, it leverages water glass to induce a CASH gel network structure generated from slag micropowder, enhancing interfacial bonding and utilizing the "rigid micro-nucleus" effect of full-size steel slag in the matrix to effectively constrain micro-slip, thereby significantly improving the resilience modulus and macroscopic strength of the solidified soil. Compared to existing solidification technologies, the innovation of this patent lies in constructing a multi-scale synergistic reinforcement mechanism of "ion modification-chemical bonding-physical interlocking," which, while achieving solid waste utilization, endows the material with ductile characteristics of "crack-resistant" and excellent elastic recovery capabilities. This aligns with the concepts of circular economy and sustainable development, and has profound significance for promoting the large-scale utilization of solid waste in the infrastructure sector and for ecological environmental protection. Summary of the Invention

[0005] The purpose of this invention is to provide a component-controlled alkali-activated full-size steel slag solidified soil material and its preparation method, in order to solve the above-mentioned technical problems.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution: This invention provides a component-controlled alkali-activated full-size steel slag solidified soil material, composed of components comprising the following parts by mass: 100 parts clay; Water 29.3~42.8 parts; 3-12 parts cement; 0.016~0.022 parts of ionic soil stabilizer; 40-150 parts of steel slag; Steel slag powder, 0-37.5 parts; 37.5-90 parts of blast furnace slag powder; 4.86 to 12.6 parts of alkaline activation solution.

[0007] Furthermore, the steel slag is divided into three grades according to particle size, of which coarse aggregate with a particle size of 13.2~31.5mm accounts for 29~31%, medium aggregate with a particle size of 2.36~13.2mm accounts for 38~42%, and fine aggregate with a particle size of 0.075~2.36mm accounts for 25~30%.

[0008] Furthermore, the specific surface area of ​​the steel slag powder is 410~470 m². 2 ·kg -1 .

[0009] Furthermore, the specific surface area of ​​the blast furnace slag powder is 400~480m². 2 ·kg -1 Its density is 2.9 g / cm³. 3 The bulk density is 982 kg / m³. 3 The particle size is 45. .

[0010] Furthermore, the alkaline activation solution is a sodium silicate solution with a volume concentration of 40-45% and a modulus of 1.0-1.6.

[0011] Furthermore, the ionic soil stabilizer is a polymer composite material that can stabilize and fix the soil.

[0012] This invention also provides a method for preparing a solidified steel slag material based on component-controlled alkali activation of all particle sizes, comprising the following steps: 1) Cement, steel slag powder and blast furnace slag powder are mixed to obtain a dry gelling powder. An alkali activation solution is added to the dry gelling powder and mixed to obtain an alkali-activated gelling material. 2) Mix the ionic soil stabilizer with water to obtain a stabilizer solution. Spray the stabilizer solution into the clay, stir, and then let it sit to obtain pretreated stabilized soil material. 3) Add steel slag to alkali-activated cementitious material, and then add pretreated solidified soil material to obtain a mixture of steel slag solidified soil with full particle size; 4) The mixture of steel slag solidified soil with full particle size is left to stand under sealed conditions, and then poured into a mold and compacted to obtain alkali-activated steel slag solidified soil material with full particle size.

[0013] Furthermore, in step 2), the curing time is 20-26 hours.

[0014] Furthermore, in step 4), the curing time is 1 to 3 hours.

[0015] The beneficial effects of this invention are: In this invention, the high-charge ions released from the ionic soil stabilizer, based on component regulation, replace exchangeable cations on the surface of soil particles, disrupting the double-layer structure and reducing the thickness of the bound water film. This promotes flocculation and aggregation of soil particles, providing an ideal framework for the growth of cementation products. The large amount of CSH and CASH gel products generated by alkali-activated slag powder fills the micropores between steel slag and soil particles, enhancing the chemical bonding force within the matrix and promoting the development of macroscopic strength in the stabilized soil. Simultaneously, the steel slag powder, acting as "rigid micronuclei," is uniformly dispersed in the continuous gel phase (these high-hardness unreacted particles effectively limit the slippage tendency of the surrounding gel, thereby dispersing micro-strain), significantly strengthening the frictional interlocking effect between aggregates, thus improving the bearing capacity and resilient modulus of the full-size steel slag stabilized soil.

[0016] This invention effectively utilizes industrial solid waste such as full-size steel slag, slag powder, and steel slag powder, reducing the demand for cement and natural stone, generating significant economic and social benefits, and contributing to sustainable development and environmental protection.

[0017] This invention utilizes the synergistic strengthening effect of ion modification, chemical bonding and physical interlocking to improve the mechanical properties of steel slag solidified soil of all particle sizes, reduce the development of compressive deformation, and give it the physical characteristic of "cracked but not scattered", effectively improving the performance of steel slag solidified soil as a road base material. Detailed Implementation

[0018] This invention provides a component-controlled alkali-activated full-size steel slag solidified soil material, composed of components comprising the following parts by mass: 100 parts clay; Water 29.3~42.8 parts; 3-12 parts cement; 0.016~0.022 parts of ionic soil stabilizer; 40-150 parts of steel slag; Steel slag powder, 0-37.5 parts; 37.5-90 parts of blast furnace slag powder; 4.86 to 12.6 parts of alkaline activation solution.

[0019] In this invention, the water content is preferably 30 to 42 parts by mass, and more preferably 32 to 40 parts by mass.

[0020] In this invention, the cement content is preferably 4 to 11 parts by weight, and more preferably 5 to 10 parts by weight.

[0021] In this invention, the content of the ionic soil stabilizer is preferably 0.018 to 0.02 parts by weight, and more preferably 0.02 parts by weight.

[0022] In this invention, the content of the steel slag is preferably 50-140 parts by weight, and more preferably 60-120 parts by weight.

[0023] In this invention, the content of the steel slag powder is preferably 5 to 35 parts by weight, and more preferably 10 to 30 parts by weight.

[0024] In this invention, the content of the alkaline activation solution is preferably 5 to 12 parts by mass, and more preferably 6 to 10 parts by mass.

[0025] In this invention, the content of the blast furnace slag powder is preferably 50-80 parts by weight, and more preferably 55-75 parts by weight.

[0026] In this invention, the clay has a liquid limit of 37.5%, a plastic limit of 21.0%, a plasticity index of 16.5, and an optimum moisture content of 15.8%.

[0027] In this invention, the steel slag is divided into three grades according to particle size, wherein coarse aggregate with a particle size of 13.2~31.5mm accounts for 29~31%, medium aggregate with a particle size of 2.36~13.2mm accounts for 38~42%, and fine aggregate with a particle size of 0.075~2.36mm accounts for 25~30%; preferably, coarse aggregate with a particle size of 13.2~31.5mm accounts for 30%, medium aggregate with a particle size of 2.36~13.2mm accounts for 41%, and fine aggregate with a particle size of 0.075~2.36mm accounts for 29%.

[0028] In this invention, the specific surface area of ​​the steel slag powder is 410~470 m². 2 ·kg -1 The preferred depth is 420~450m 2 ·kg -1 Further preferred is 430~440m 2 ·kg -1 .

[0029] In this invention, the steel slag powder comprises, by mass fraction, 13.95% SiO2, 12.11% Fe2O3, 5.01% MgO, 8.76% Al2O3, 48.08% CaO, 0.14% K2O, 0.397% Cl, 0.779% Na2O, 1.87% MnO, 0.348% F, 2.97% SO3, and 5.586% other components.

[0030] In this invention, the specific surface area of ​​the blast furnace slag powder is 400~480m². 2 ·kg -1 The preferred value is 410~470m 2 ·kg -1 Further preferred is 420~460m 2 ·kg -1 Its density is 2.9 g / cm³. 3 The bulk density is 982 kg / m³. 3 The particle size is 45. .

[0031] In this invention, the blast furnace slag powder comprises, by mass fraction, 32.869% SiO2, 0.274% Fe2O3, 9.662% MgO, 17.873% Al2O3, 34.581% CaO, 0.4% K2O, 0.73% Na2O, 0.16% MnO, and 3.451% other components.

[0032] In this invention, the alkaline activation solution is a sodium silicate solution with a volume concentration of 40-45%, preferably 42% and a modulus of 1.0-1.6, preferably 1.0, 1.2, 1.4, or 1.6.

[0033] In this invention, the ionic soil stabilizer is a polymer composite material that can stabilize and fix the soil, preferably EFS-001 soil stabilizer from Zhongke Shenglian (Beijing) Environmental Protection Technology Co., Ltd., also known as EFSen soil stabilizer.

[0034] In this invention, the ionic soil stabilizer is used to weaken the electric double layer on the surface of clay particles and promote particle flocculation and agglomeration; the cement, blast furnace slag powder, optional steel slag powder and sodium silicate solution react to generate CSH and CASH gels, which are used to fill the pores between steel slag and solidified soil particles and form a cemented structure; the steel slag and optional unreacted steel slag powder form a rigid skeleton and micro-core interlocking structure, thereby constituting a synergistic enhancement system of ion modification, chemical cementation and physical interlocking.

[0035] This invention also provides a method for preparing a solidified steel slag material based on component-controlled alkali activation of all particle sizes, comprising the following steps: 1) Cement, steel slag powder and blast furnace slag powder are mixed to obtain a dry gelling powder. An alkali activation solution is added to the dry gelling powder and mixed to obtain an alkali-activated gelling material. 2) Mix the ionic soil stabilizer with water to obtain a stabilizer solution. Spray the stabilizer solution into the clay, stir, and then let it sit to obtain pretreated stabilized soil material. 3) Add steel slag to alkali-activated cementitious material, and then add pretreated solidified soil material to obtain a mixture of steel slag solidified soil with full particle size; 4) The mixture of steel slag solidified soil with full particle size is left to stand under sealed conditions, and then poured into a mold and compacted to obtain alkali-activated steel slag solidified soil material with full particle size.

[0036] In this invention, in step 2), the curing time is 20-26 hours, preferably 24 hours.

[0037] In this invention, in step 4), the curing time is 1 to 3 hours, preferably 2 hours.

[0038] The technical solutions provided by the present invention will be described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0039] Example 1

[0040] A method for preparing alkali-activated full-size steel slag solidified soil includes clay, water, cement, ionic soil stabilizer, steel slag, blast furnace slag powder, and sodium silicate solution. The following ingredients were weighed according to weight fractions: 100 parts clay, 29.3 parts water, 9 parts cement, 0.02 parts ionic soil stabilizer, 150 parts steel slag, 45 parts blast furnace slag powder, 0 parts steel slag powder, and 4.86 parts sodium silicate solution. The alkali-activated full-size steel slag stabilized soil was prepared by mixing the ingredients according to the above proportions. The results of the performance test are shown in Table 1.

[0041] The steel slag is classified into three grades according to particle size: coarse aggregate (13.2-31.5 mm) accounts for 30%, medium aggregate (2.36-13.2 mm) accounts for 41%, and fine aggregate (0.075-2.36 mm) accounts for 29%. The specific surface area of ​​the steel slag powder is 450 m². 2 ·kg -1 The specific surface area of ​​blast furnace slag powder is 430 m². 2 ·kg -1 The modulus of sodium silicate solution is 1.2.

[0042] Preparation method: 1) Weigh the required cement, steel slag powder and blast furnace slag powder and mix them thoroughly to obtain a dry cementitious powder. At the same time, add sodium silicate solution to some water and mix thoroughly to obtain an alkali-activated solution. Finally, add the alkali-activated solution to the dry cementitious powder and mix thoroughly to obtain an alkali-activated cementitious material. 2) Weigh the required clay and ionic soil stabilizer, add the ionic soil stabilizer to the remaining water and stir thoroughly to obtain a stabilizer solution, then spray the stabilizer solution evenly onto the clay, stir thoroughly and let it sit for 24 hours to obtain the pretreated stabilized soil material. 3) Add the weighed steel slag to the alkali-activated cementitious material according to the mixing ratio and stir thoroughly. Then add the pretreated solidified soil material and continue stirring to obtain a steel slag solidified soil mixture with full particle size. 4) The mixture of steel slag solidified soil with full particle size was left to stand for 2 hours under sealed conditions, and then poured into a cylindrical mold and compacted to obtain alkali-activated steel slag solidified soil material with full particle size.

[0043] Example 2

[0044] A method for preparing alkali-activated full-size steel slag solidified soil includes clay, water, cement, ionic soil stabilizer, steel slag, blast furnace slag powder, and sodium silicate solution. The following ingredients were weighed according to weight fractions: 100 parts clay, 33.8 parts water, 9 parts cement, 0.02 parts ionic soil stabilizer, 150 parts steel slag, 60 parts blast furnace slag powder, 0 parts steel slag powder, and 6.21 parts sodium silicate solution. The alkali-activated full-size steel slag stabilized soil prepared by mixing these ingredients was tested, and the results are shown in Table 1.

[0045] The steel slag is classified into three grades according to particle size: coarse aggregate (13.2-31.5 mm) accounts for 30%, medium aggregate (2.36-13.2 mm) accounts for 41%, and fine aggregate (0.075-2.36 mm) accounts for 29%. The specific surface area of ​​the steel slag powder is 450 m². 2 ·kg -1 The specific surface area of ​​blast furnace slag powder is 430 m². 2 ·kg -1 The modulus of sodium silicate solution is 1.2.

[0046] The preparation method is the same as in Example 1.

[0047] Example 3

[0048] A method for preparing alkali-activated full-size steel slag solidified soil includes clay, water, cement, ionic soil stabilizer, steel slag, blast furnace slag powder, and sodium silicate solution. The following ingredients were weighed according to weight fractions: 100 parts clay, 38.3 parts water, 9 parts cement, 0.02 parts ionic soil stabilizer, 150 parts steel slag, 75 parts blast furnace slag powder, 0 parts steel slag powder, and 7.56 parts sodium silicate solution. Alkali-activated, full-size steel slag-stabilized soil was prepared by mixing these ingredients. The performance results are shown in Table 1. The steel slag was divided into three grades according to particle size: coarse aggregate (13.2–31.5 mm) accounted for 30%, medium aggregate (2.36–13.2 mm) accounted for 41%, and fine aggregate (0.075–2.36 mm) accounted for 29%. The specific surface area of ​​the steel slag powder was 450 m². 2 ·kg -1 The specific surface area of ​​blast furnace slag powder is 430 m².2 ·kg -1 The modulus of sodium silicate solution is 1.2.

[0049] The preparation method is the same as in Example 1.

[0050] Example 4

[0051] A method for preparing alkali-activated full-size steel slag solidified soil includes clay, water, cement, ionic soil stabilizer, steel slag, blast furnace slag powder, and sodium silicate solution. The following ingredients were weighed according to weight fractions: 100 parts clay, 42.8 parts water, 9 parts cement, 0.02 parts ionic soil stabilizer, 150 parts steel slag, 90 parts blast furnace slag powder, 0 parts steel slag powder, and 8.91 parts sodium silicate solution. The alkali-activated full-size steel slag stabilized soil was prepared by mixing the ingredients according to this ratio. The results of its performance testing are shown in Table 1.

[0052] The steel slag is classified into three grades according to particle size: coarse aggregate (13.2-31.5 mm) accounts for 30%, medium aggregate (2.36-13.2 mm) accounts for 41%, and fine aggregate (0.075-2.36 mm) accounts for 29%. The specific surface area of ​​the steel slag powder is 450 m². 2 ·kg -1 The specific surface area of ​​blast furnace slag powder is 430 m². 2 ·kg -1 The modulus of sodium silicate solution is 1.2.

[0053] The preparation method is the same as in Example 1.

[0054] Example 5

[0055] A method for preparing alkali-activated full-size steel slag solidified soil includes clay, water, cement, ionic soil stabilizer, steel slag, blast furnace slag powder, and sodium silicate solution. The following ingredients were weighed according to weight fractions: 100 parts clay, 38.3 parts water, 9 parts cement, 0.02 parts ionic soil stabilizer, 150 parts steel slag, 75 parts blast furnace slag powder, 0 parts steel slag powder, and 5.04 parts sodium silicate solution. The alkali-activated full-size steel slag stabilized soil was prepared by mixing the ingredients according to the above proportions. The results of the performance test are shown in Table 1.

[0056] The steel slag is classified into three grades according to particle size: coarse aggregate (13.2-31.5 mm) accounts for 30%, medium aggregate (2.36-13.2 mm) accounts for 41%, and fine aggregate (0.075-2.36 mm) accounts for 29%. The specific surface area of ​​the steel slag powder is 450 m². 2 ·kg -1 The specific surface area of ​​blast furnace slag powder is 430 m². 2 ·kg -1The modulus of sodium silicate solution is 1.2.

[0057] The preparation method is the same as in Example 1.

[0058] Example 6

[0059] A method for preparing alkali-activated full-size steel slag solidified soil includes clay, water, cement, ionic soil stabilizer, steel slag, blast furnace slag powder, and sodium silicate solution. The following ingredients were weighed according to weight fractions: 100 parts clay, 38.3 parts water, 9 parts cement, 0.02 parts ionic soil stabilizer, 150 parts steel slag, 75 parts blast furnace slag powder, 0 parts steel slag powder, and 10.08 parts sodium silicate solution. The alkali-activated full-size steel slag stabilized soil was prepared by mixing the ingredients according to the specified weight fractions. The results of the performance testing are shown in Table 1.

[0060] The steel slag is classified into three grades according to particle size: coarse aggregate (13.2-31.5 mm) accounts for 30%, medium aggregate (2.36-13.2 mm) accounts for 41%, and fine aggregate (0.075-2.36 mm) accounts for 29%. The specific surface area of ​​the steel slag powder is 450 m². 2 ·kg -1 The specific surface area of ​​blast furnace slag powder is 430 m². 2 ·kg -1 The modulus of sodium silicate solution is 1.2.

[0061] The preparation method is the same as in Example 1.

[0062] Example 7

[0063] A method for preparing alkali-activated full-size steel slag solidified soil includes clay, water, cement, ionic soil stabilizer, steel slag, blast furnace slag powder, and sodium silicate solution. The following ingredients were weighed according to weight fractions: 100 parts clay, 38.3 parts water, 9 parts cement, 0.02 parts ionic soil stabilizer, 150 parts steel slag, 75 parts blast furnace slag powder, 0 parts steel slag powder, and 12.6 parts sodium silicate solution. The alkali-activated full-size steel slag stabilized soil was prepared by mixing the ingredients according to the above proportions. The results of the performance test are shown in Table 1.

[0064] The steel slag is classified into three grades according to particle size: coarse aggregate (13.2-31.5 mm) accounts for 30%, medium aggregate (2.36-13.2 mm) accounts for 41%, and fine aggregate (0.075-2.36 mm) accounts for 29%. The specific surface area of ​​the steel slag powder is 450 m². 2 ·kg -1 The specific surface area of ​​blast furnace slag powder is 430 m². 2 ·kg -1 The modulus of sodium silicate solution is 1.2.

[0065] The preparation method is the same as in Example 1.

[0066] Example 8

[0067] A method for preparing alkali-activated full-size steel slag solidified soil includes clay, water, cement, ionic soil stabilizer, steel slag, blast furnace slag powder, steel slag powder, and sodium silicate solution. The following ingredients were weighed according to weight fractions: 100 parts clay, 38.3 parts water, 9 parts cement, 0.02 parts ionic soil stabilizer, 150 parts steel slag, 56.25 parts blast furnace slag powder, 18.75 parts steel slag powder, and 7.56 parts sodium silicate solution. The alkali-activated full-size steel slag stabilized soil prepared by mixing these ingredients was tested, and the results are shown in Table 1.

[0068] The steel slag is classified into three grades according to particle size: coarse aggregate (13.2-31.5 mm) accounts for 30%, medium aggregate (2.36-13.2 mm) accounts for 41%, and fine aggregate (0.075-2.36 mm) accounts for 29%. The specific surface area of ​​the steel slag powder is 450 m². 2 ·kg -1 The specific surface area of ​​blast furnace slag powder is 430 m². 2 ·kg -1 The modulus of sodium silicate solution is 1.2.

[0069] The preparation method is the same as in Example 1.

[0070] Example 9

[0071] A method for preparing alkali-activated full-size steel slag solidified soil includes clay, water, cement, ionic soil stabilizer, steel slag, blast furnace slag powder, steel slag powder, and sodium silicate solution. The following ingredients were weighed according to weight fractions: 100 parts clay, 38.3 parts water, 9 parts cement, 0.02 parts ionic soil stabilizer, 150 parts steel slag, 37.5 parts blast furnace slag powder, 37.5 parts steel slag powder, and 7.56 parts sodium silicate solution. The alkali-activated full-size steel slag stabilized soil prepared by mixing these ingredients was tested, and the results are shown in Table 1.

[0072] The steel slag is classified into three grades according to particle size: coarse aggregate (13.2-31.5 mm) accounts for 30%, medium aggregate (2.36-13.2 mm) accounts for 41%, and fine aggregate (0.075-2.36 mm) accounts for 29%. The specific surface area of ​​the steel slag powder is 450 m². 2 ·kg -1 The specific surface area of ​​blast furnace slag powder is 430 m². 2 ·kg -1 The modulus of sodium silicate solution is 1.2.

[0073] The preparation method is the same as in Example 1.

[0074] Comparative Example 1

[0075] Same as Example 1, except that no steel slag is added. The preparation method is the same as in Example 1.

[0076] Comparative Example 2

[0077] Same as Example 1, except that common soil stabilizer polyacrylamide is used instead of ionic soil stabilizer. The preparation method is the same as in Example 1.

[0078] According to the "Test Procedure for Inorganic Binder Stabilized Materials in Highway Engineering" (JTG E51-2009) and the "Test Procedure for Highway Geotechnical Engineering" (JTG3430-2020), the performance of the alkali-activated full-size steel slag solidified soil prepared in Examples 1, 2, 3, 4, 5, 6, 7, 8, 9 and the comparative example was tested.

[0079] The performance indicators of the full-size steel slag solidified soil prepared according to the embodiment are shown in Table 1.

[0080] Table 1 Performance test results of each embodiment

[0081] As shown in Table 1, based on the mass of steel slag particles, the 28-day compressive strength of the test blocks significantly increased when the content of blast furnace slag powder increased from 30% to 50%. With the increase in the content of cementitious components, a large amount of amorphous glass rich in potential energy depolymerized, generating more CSH and CASH network cementitious structures, which fully filled the micropores between soil particles and steel slag aggregate, thus greatly improving the strength performance of the full-size steel slag-stabilized soil. Compared with a water glass content of 6%, the 28-day compressive strength of the test blocks increased by 48.12% when the water glass content was 9%. Under suitable alkaline activation conditions, the silicate oligomers released by the water glass precipitated in situ in the interface transition zone between the aggregate and the slurry, generating hydration products, significantly enhancing the mechanical interlocking and chemical bonding between the matrix and the aggregate, directly improving the tensile and bearing capacity of the full-size steel slag-stabilized soil. Meanwhile, compared to the sample without added steel slag powder, the resilience modulus of the specimen steadily increased with the increase in the steel slag powder substitution rate. The incompletely hydrated steel slag powder particles have extremely high hardness, and as "rigid micro-nuclei," they are uniformly dispersed in the continuous gel phase, strengthening the interlocking effect of the skeleton and effectively limiting the slippage tendency of the surrounding gel, thus significantly enhancing the ability of the full-size steel slag-solidified soil to resist elastic deformation. Comprehensive analysis shows that the optimal mix proportion for the full-size steel slag-solidified soil is: a steel slag to clay mass ratio of 6:4; based on the steel slag mass, the blast furnace slag powder content is 25%, and the steel slag powder content is 25%; based on the total dry powder mass of cement, blast furnace slag powder, and steel slag powder, the sodium silicate solution content is 9%; and the modulus of the sodium silicate solution is 1.2.

[0082] As shown in the above embodiments, this invention provides a component-controlled alkali-activated full-size steel slag solidified soil material and its preparation method. This invention utilizes the synergistic effect of ion modification, alkali-activated cementation, and steel slag micronucleus reinforcement to promote soil particle flocculation, gel-filled interstitial cementation, and enhanced skeleton interlocking, thereby improving strength and deformation resistance. This invention can significantly improve the early bearing capacity, crack resistance, and deformation resistance of solidified soil while increasing the utilization rate of steel slag solid waste, making the material suitable for engineering scenarios such as road base courses and subbase courses. This method reduces the amount of natural aggregates and cement used, which is beneficial for the large-scale resource utilization of industrial solid waste such as steel slag, and has good engineering application value and environmental benefits.

[0083] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A component-controlled alkali-activated full-size steel slag solidified soil material, characterized in that, It consists of components comprising the following parts by mass: 100 parts clay; Water 29.3~42.8 parts; 3-12 parts cement; 0.016~0.022 parts of ionic soil stabilizer; 40-150 parts of steel slag; Steel slag powder, 0-37.5 parts; 37.5-90 parts of blast furnace slag powder; 4.86 to 12.6 parts of alkaline activation solution.

2. The component-controlled alkali-activated full-size steel slag solidified soil material according to claim 1, characterized in that, The steel slag is divided into three grades according to particle size, of which coarse aggregate with a particle size of 13.2~31.5mm accounts for 29~31%, medium aggregate with a particle size of 2.36~13.2mm accounts for 38~42%, and fine aggregate with a particle size of 0.075~2.36mm accounts for 25~30%.

3. The component-controlled alkali-activated full-size steel slag solidified soil material according to claim 1 or 2, characterized in that, The specific surface area of ​​the steel slag powder is 410~470 m². 2 ·kg -1 .

4. The component-controlled alkali-activated full-size steel slag solidified soil material according to claim 3, characterized in that, The specific surface area of ​​the blast furnace slag powder is 400~480m². 2 ·kg -1 Its density is 2.9 g / cm³. 3 The bulk density is 982 kg / m³. 3 The particle size is 45. .

5. The component-controlled alkali-activated full-size steel slag solidified soil material according to claim 1, characterized in that, The alkaline activation solution is a sodium silicate solution with a volume concentration of 40-50% and a modulus of 1.0-1.

6.

6. The component-controlled alkali-activated full-size steel slag solidified soil material according to claim 1, 2, or 5, characterized in that, The ionic soil stabilizer is a polymer composite material that can stabilize and fix the soil.

7. The preparation method of the steel slag solidified soil material based on component-controlled alkali activation of full particle size as described in any one of claims 1 to 6, characterized in that, Includes the following steps: 1) Cement, steel slag powder and blast furnace slag powder are mixed to obtain a dry gelling powder. An alkali activation solution is added to the dry gelling powder and mixed to obtain an alkali-activated gelling material. 2) Mix the ionic soil stabilizer with water to obtain a stabilizer solution. Spray the stabilizer solution into the clay, stir, and then let it sit to obtain pretreated stabilized soil material. 3) Add steel slag to alkali-activated cementitious material, and then add pretreated solidified soil material to obtain a mixture of steel slag solidified soil with full particle size; 4) The mixture of steel slag solidified soil with full particle size is left to stand under sealed conditions, and then poured into a mold and compacted to obtain alkali-activated steel slag solidified soil material with full particle size.

8. The preparation method according to claim 7, characterized in that, In step 2), the curing time is 20-26 hours.

9. The preparation method according to claim 7 or 8, characterized in that, In step 4), the curing time is 1-3 hours.

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