Industrial Waste Fly Ash Research Articles

Recent Developments on Aluminum 7075-Based Composite with Industrial Waste Fly Ash by Stir Casting and Their Applications

Recent Developments on Aluminum 7075-Based Composite with Industrial Waste Fly Ash by Stir Casting and Their Applications

Evaluation on Preparation and Performance of a Low-Carbon Alkali-Activated Recycled Concrete under Different Cementitious Material Systems.

A green, low-carbon concrete is a top way to recycle waste in construction. This study uses industrial solid waste slag powder (S95) and fly ash (FA) as binders to completely replace cement. This study used recycled coarse aggregate (RCA) instead of natural coarse aggregate (NCA). This is to prepare alkali-activated recycled concrete (AARC) with different cementitious material systems. Alkali-activated concrete (AAC) mixtures are modified for strength and performance based on the mechanical qualities and durability of AARC. Also, the time-varying effects of the environment on AARC properties are explored. The results show that with the performance enhancement of RCA, the mechanical performance of AARC is significantly improved. As RCA's quality improves, so does AARC's compressive strength. At a cementitious material content of 550 kg/m3, AARC's 28d compressive strengths using I-, II-, and III-class RCA were reduced by 2.2%, 12.7%, and 21.8%, respectively. I-class AARC has characteristics similar to natural aggregate concrete (NAC) in terms of shrinkage, resistance to chloride penetration, carbonization, and frost resistance. AARC is a new type of green building material that uses industrial solid waste to prepare alkali-activated cementitious materials. It can effectively reduce the amount of cement and alleviate energy consumption. This is conducive to the reuse of resources, environmental protection, and sustainable development.

Life cycle assessment of ceramic tiles manufactured using industrial waste fly ash

Sustainability in the ceramic tile industry is critical due to its significant resource and energy consumption. With limited life cycle assessment (LCA) studies on waste materials in tile production, a research gap exists specifically for industrial waste fly ash (IWA). Building upon previous research that has confirmed the technical feasibility of IWA as a sustainable alternative material in ceramic tile, this study explores the environmental and economic feasibility of replacing potash feldspar with IWA in ceramic tiles. A comparative LCA across scenarios with varying IWA additions from 0 % to 30 % was conducted, focusing on six key environmental impact categories: climate change, terrestrial acidification, human toxicity, terrestrial ecotoxicity, freshwater eutrophication, and fossil depletion. Additionally, a sensitivity analysis on increased production energy and an environmental life cycle cost analysis (ELCC) were performed. Results reveal significant reductions in environmental impacts with increased IWA incorporation compared to the conventional construction. Notably, the IWA30 (30 % IWA addition) scenario, which entirely substitutes potash feldspar, achieves the most substantial benefits, reducing climate change impacts by 8 %, terrestrial acidification by 10 %, and terrestrial ecotoxicity by 22 %. These reductions demonstrate that incorporating IWA significantly decreases the overall environmental footprint of ceramic tile production by reducing the reliance on non-renewable resources and mitigating pollution. IWA30 also proves to be the most cost-effective option, with an 11 % cost reduction due to IWA's availability as a waste material. Overall, adopting IWA decreases the environmental burden and enhances economic viability, providing strong incentives for industries to adopt more sustainable practices by minimising waste management challenges and raw material consumption.

Uncovering the potential of industrial waste: turning discarded resources into sustainable advanced materials

To identify solutions for utilizing industrial wastes (slag, sludge, fly ash, and bottom ash) in the development of pro-environmental systems, this paper reviews existing literature and explores material characterization methods. A review analysis was conducted to uncover their potential, and it was found that many utilizations can be made to recycle them into sustainable materials. Structure characterization, optical-dielectric function, and morphology analysis were analyzed to confirm the recent review. Structural properties are represented by crystallite size and crystallinity, where nickel slag shows the smallest distribution (55 ± 10) nm with the highest crystallinity (25.42%), indicating its association with uniformity of response to external disturbances and micro-structural stability. From the analysis of optical and dielectric functions via Kramers Kronig relation, the widening of ∆(LO−TO) was shown by fly ash and slag indicating stable bonding suitable as x-ray shielding and sensor, while high electron loss functions were shown by sludge and bottom ash indicating high potential electronic transition performance. Based on their chemical and physical properties, these industrial wastes are not limited as construction materials and can even be upgraded to more advanced development materials.

Synergistic effects of graphene oxide and fly ash on rheology, mechanical properties, and microstructure of highly-flowable cementitious grouts

Due to their excellent mechanical strength and low pric, cementitious grouts have emerged as the popular for grouting applications. However, excessive use of cement results in significant energy consumption and associated carbon emissions, which is a concern from a sustainability perspective. In this study, inexpensive industrial waste fly ash (FA) was used to enhance the performance of graphene oxide (GO)-based cementitious grouts. The influence of varying dosages of GO and FA on the rheology, mechanical strength, durability, and microstructure development of cementitious pastes was investigated. The results show that adding FA to GO-based cementitious grouts improves the workability of the paste. The high-flowability cementitious grouts with combined GO and FA exhibit Bingham's fluid behavior, indicating that the synergistic effect of GO and FA does not alter the flow behavior of the paste. Further, the relationship between the rheological parameters of the modified paste and time was developed. For 0.03 wt% GO and 20 wt% FA incorporation, the flexural and compressive strengths of the paste at 28 days increased by 28.5% and 30.4%, respectively, compared to the blank group. The chloride ion penetration coefficient at 180 days was 1.007, indicating that FA could effectively replace a portion of the cement while enhancing the durability of the grout. Microstructural investigations confirmed that the synergistic effect of GO and FA does not generate new hydration products. GO accelerates the hydration reaction and activates the secondary pozzolanic effect of FA, forming more hydration products and thereby enhancing the mechanical strength and durability of the grout.

Wastewater Treatment Utilizing Industrial Waste Fly Ash as a Low-Cost Adsorbent for Heavy Metal Removal: Literature Review

Wastewater discharges from industrial processes typically include elevated concentrations of contaminants, which largely consist of potentially harmful chemicals such as heavy metals. These contaminants are characterized by their slow rate of decomposition. Hence, the removal of these metallic ions from effluents poses a challenge. Among different treatments, the adsorption approach has considerable potential due to its ability to effectively eliminate both soluble and insoluble pollutants from effluent, even at lower levels of concentration. Of various wastes, fly ash (FA) material has been the subject of attention because it is abundant, has favorable qualities, and contains a high percentage of minerals. This review investigates multiple facets, with a specific focus on the application of FA, an industrial byproduct, as an adsorbent in removing heavy metals. A comprehensive examination was conducted on a range of concerns pertaining to the pollution caused by metallic ions, including the underlying causes, levels of contamination, health implications of heavy metals, and removal methods. Multiple factors were found to affect the adsorption process. Of all the factors, the pH value considerably influences the elimination of heavy metals. An acidic pH range of 2.5–4.5 was found to be optimal for achieving the highest possible elimination of As(V), Cu(II), Hg(II), and Cr(VI). The latter elimination rate reached 89% at the optimal pH level. Most heavy metals’ adsorption isotherms conformed to the Langmuir or Freundlich models, while the pseudo-second-order kinetics provided a satisfactory match for their removal. Using a raw FA, adsorption capacities were achieved in the removal of metallic ions, Ni(II), Pb(II), and Cr(VI), that ranged from 14.0 to 23.9 mg g−1. Meanwhile, the FA-zeolite showed a remarkable capacity to adsorb ions Mn(II), Ni(II), Cd(II), Cu(II), and Pb(II), with values ranging from about 31 to 66 mg g−1. The cost analysis showed that the treatment of FA is economically advantageous and may result in significant cost reductions in comparison to commercial adsorbents. In summary, FA is an inexpensive waste material with potential for water treatment applications and several other purposes due to its excellent chemical and mineralogical composition.

Microstructural characterization and the influence of the chemical composition of the raw material mix on the physicochemical characteristics of waste-derived ceramic aggregates

This work presents the possibility of using a mixture of different mining and industrial wastes (fly ash, waste rock, glass cullet and waste solution as a binder) for ceramic aggregate production with the application of microwave radiation. The effect of the chemical composition of the raw material mix reflected by F/SA ratio (flux oxides/SiO2 + Al2O3) on the mechanical and microstructural properties of the aggregates was evaluated using X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), and X-ray nanotomography (nCT). A higher proportion of fly ash relative to waste rock in the mixture composition led to an increase in the F/SA ratio. The greater the F/SA, the higher the values of particle density and compressive strength, ranging from 1.72 to 1.87 g/cm3 and 6.31–7.31 MPa, respectively. Moreover, higher F/SA led to lower water absorption and porosity, which oscillated between 2.12 - 3.44% and 3.22–5.00%, respectively. X-ray nanotomography studies revealed an increasing contribution of larger pores with a radius of and an overall increase in porosity as the F/SA ratio rose. This finding was further confirmed by SEM investigations. TG-QMS analysis showed that organic matter could act as a pore-forming agent. The basic physical and mechanical paramaters of the obtained ceramic aggregates indicate the suitability of the studied wastes for the production of valuable construction materials.

Preparation and mechanical characterization of multi-functional high-ductility engineered magnesium oxysulfate cement-based composites

Aiming at the integrated requirements of building energy saving and thermal insulation reinforcement in reinforcement engineering, the technology of preparing multi-functional high-ductility engineered magnesium oxysulfate cement-based composites (MOSC-ECC) by magnesium oxysulfate cement (MOSC) was proposed; the mechanism of industrial waste fly ash (FA) to improve the ductility of MOSC-ECC was explored; the effects of FA on the density, thermal conductivity and water resistance of MOSC-ECC were studied; the phase composition and microstructure of the hydration products of MOSC-ECC were analyzed. The results show that the incorporation of FA instead of light-burned magnesium oxide (LB-MgO) powder of equal mass can effectively reduce the cracking strength, fracture toughness, density and thermal conductivity of the matrix, and improve the ductility and multiple cracking ability of MOSC-ECC. The incorporation of hydrophobic agent made MOSC-ECC have excellent water resistance. The findings of this study provide useful knowledge for realizing the integrated design of thermal insulation and reinforcement of structures, which is of great significance for promoting the engineering application of ECC and the promotion of energy-saving green building materials.

Adsorption/Desorption Performances of Simulated Radioactive Nuclide Cs+ on the Zeolite-Rich Geopolymer from the Hydrothermal Synthesis of Fly Ash

The operation of nuclear power plants generates a large amount of low- and intermediate-level radioactive waste liquid. Zeolite-rich geopolymers, which are synthesized under hydrothermal conditions from industrial waste fly ash, can effectively immobilize radioactive nuclides. In this study, the synthesis law of zeolite-rich geopolymers and the adsorption/desorption performances of radioactive nuclide Cs+ were researched using XRD, SEM and ICP. The results show that the increase in curing temperatures and NaOH concentrations leads to the transformation of Y-type zeolite to chabazite and cancrinite at low NaNO3 concentrations. However, at high NaNO3 concentrations, NaOH above 2 M has no obvious effect on the phase transformation of the main zeolite of chabazite and cancrinite. In the adsorption and desorption experiment of Cs+ on the chabazite/garronite-rich geopolymer, it was found that the adsorption of Cs+ in the low initial concentration range is more suitable for the Freundlich equation, while the Langmuir equation fits in the adsorption process at the high initial concentration range. Moreover, the desorption kinetics of Cs+ are in good agreement with the pseudo-second-order rate equation. Thus, the adsorption of Cs+ on chabazite/garronite-rich geopolymers is controlled by both physical and chemical reactions, while desorption is a chemical process.

Experimental Study on Enhanced Phosphorus Removal Using Zirconium Oxychloride Octahydrate-Modified Efficient Phosphorus Removal Composite

In addressing eutrophication and enhancing water quality, this study builds upon previous research involving the development of an Efficient Phosphorus Removal Composite (EPRC), a material created using modified industrial wastes (steel slag and fly ash) as adsorbent substrates, supplemented with a binder and porosity-forming agent. In this investigation, the EPRC was further enhanced through the addition of zirconium oxychloride octahydrate, resulting in the production of Zr-EPRC particles as reinforced phosphorus removal materials. Comparative experiments were conducted to assess different methods for preparing Zr-EPRC, the static adsorption performance, and dynamic adsorption behavior. The optimal preparation of Zr-EPRC was achieved by separately modifying the base materials, steel slag and fly ash. Loading with mass ratios of zirconium chloride octahydrate to fly ash and steel slag at 0.4 and 0.6, respectively, for a duration of 12 h at a pH of 10 yielded the best results. In static adsorption experiments conducted at temperatures of 15 °C, 25 °C, and 35 °C, Zr-EPRC exhibited saturated phosphorus adsorption capacities of 11.833 mg/g (variance = 0.993), 12.550 mg/g (variance = 0.993), and 13.462 mg/g (variance = 0.996), respectively. Zr-EPRC emerges as a cost-effective and readily available solution with promising stability for general wastewater treatment applications, contributing significantly to the mitigation of eutrophication and the improvement of water quality.

Industrial waste fly ash experimental research on the thermal, mechanical, and electrical characteristics of AA8011 metal matrix composites

Industrial waste fly ash experimental research on the thermal, mechanical, and electrical characteristics of AA8011 metal matrix composites

Engineering properties and optimal design of foam lightweight soil composite fly ash: An eco-friendly subgrade material

Foam lightweight soil is used frequently in engineering construction for soft soil areas due to its superior lightness and economy, but its greater cement usage will result in cost increase, resource waste, and environmental pollution. This study modified foam lightweight soil with industrial solid waste (fly ash) in place of some cement to propose an eco-friendly and useful lightweight subgrade filling material. A series of macro-micro tests were conducted to investigate the engineering properties and micro-mechanisms of foam lightweight soil composite fly ash (FLS). The results showed that the axial stress-strain and shear stress-displacement curves of FLS showed softening types. The fluidity, compressive strength, toughness and shear strength of FLS first increased and then decreased with the increasing fly ash content. The mechanical strength of 20% FLS was the optimal value for meeting the application requirements of subgrade engineering. Due to the volcanic ash and micro-aggregation effects, fly ash consumed the calcium hydroxide to produce more calcium silicate hydrate for filling the pores of sample and improving its internal structure. According to the results of numerical simulation, the settlement deformation and lateral deformation of subgrade could be better controlled by using 20%FLS as filling material compared with ordinary soil. Consequently, it is feasible to apply FLS in subgrade engineering.

Fabrication of sustainable closed-cell aluminium foams using recycled fly ash and eggshell powder

Closed-cell aluminum foams are a novel materials which consists of unique properties such as good mechanical strength combining low mass and high stiffness, high energy and sound absorption, corrosion resistance, and recyclability. In spite of these potential properties, the usage of expensive constituents (stabilizing and foaming agents) and processing methods of making foams hinder its wide spread usage in industrial applications. This work involves the use of cost-effective constituents for processing aluminium foams by stir casting technique. The industrial waste fly ash (Class-F) is used as a source of stabilizing agent and for the first time the viability of waste chicken egg shell is used as a foaming agent to produce sustainable aluminium foams. Ex-situ characterization investigations are carried out on the manufactured foams in accordance with industry standards. It is evident that the produced foams have a fine cell structures with appreciable compressive strength and energy absorption characteristics. The experimental findings indicate that eggshell powder can be used as a cost-effective foaming agent for synthesizing aluminium foams and fly ash as foam stabilizing agent.

Study on preparation of ADP composite colloid by the effective component from activated fly ash and its fire prevention mechanism

The application of industrial solid waste fly ash (FA) to fire prevention material is an effective way to realize its large-scale resource utilization. How to improve the performance and application range of FA type fire-fighting materials has become an engineering roadblock. In this study, the activation technology was introduced to extract effective component from FA, and the Ash-Diatomite-Polyacrylamide (ADP) colloid with double-aggregate was prepared mainly by activated modified FA. The ICP data of active substance in liquid phase indicates that acid-base combined excitation can release a large number of active components through chemical activation of FA. The physical properties of ADP colloids were tested by measuring the colloid permeability, water retention, and thermal stability. Meanwhile, the chemical flame retardancy of colloids was also determined by the inhibition experiment and thermogravimetric analysis. Experiments results indicate that Al3+ and Fe3+ released by excitation can be acted as cross-linking agents in the formation of colloids, and Ca2+ and Mg2+ released can be used as inhibitors for coal spontaneous combustion. ADP colloid can still inhibit the release of CO and CO2 at 220 °C with higher inhibition rates. The values of activation energy prove that ADP composite colloid can effectively increase the energy required by the interaction between coal and oxygen. Moreover, the multi-component cooperative fire-prevention mechanism of ADP was explored based on the effective composition, gelling mechanism, and fire-retarding action sequence of composite colloid.

Study of the Design and Mechanical Properties of the Mix Proportion for Desulfurization Gypsum–Fly Ash Flowable Lightweight Soil

In order to solve the global problem of bridge head jumping caused by the insufficient compaction of the roadbed in the transition section of highways and bridges, a desulfurization gypsum–fly ash flowable lightweight soil without vibration, capable of self-compaction, low bulk density, and economic and environmental protection, has been developed. This study selected low-grade cement, industrial waste (fly ash and desulfurization gypsum), and Yellow River silt as the raw materials for the design of the mix ratio of a desulfurization gypsum–fly ash flow-state lightweight soil mix. Through multiple indoor experiments, the influence of cement content, silt content, and the fly ash/desulfurization gypsum quality ratio on its fluidity and mechanical properties was systematically studied. The stress–strain relationship under uniaxial compression was analyzed and the strength formation mechanism was revealed through scanning electron microscopy (SEM). The results show that the mechanical properties of the prepared desulfurization gypsum–fly ash flowable lightweight soil meet the engineering requirements. Increasing both the cement and fly ash content results in the decreased fluidity of the desulfurization gypsum and fluidized fly ash. However, as the mass ratio of fly ash to desulfurization gypsum increases, the fluidity reaches its maximum when the mass ratio of fly ash to desulfurization gypsum is 2:1. Based on the stress–strain relationship test results, a uniaxial compressive constitutive model of the desulfurization gypsum–fly ash flowable lightweight soil was proposed. The model was fitted and analyzed with the test results, and the correlation was greater than 0.96. The high degree of agreement showed that desulfurization gypsum can promote the disintegration of fly ash, thereby increasing the specific surface area. This provides more contact points, promotes the hardening process, and enhances the interlocking force between particles and the formation of cementitious substances, further enhancing strength.

Mechanical Characterization of Geopolymer Paste and Mortar Fabricated from Alum Sludge and Fly Ash

This study evaluated the effect of alum sludge as an alternative to fly ash in fabricating geopolymer paste and mortar. The blending of this industrial waste (alum sludge and fly ash) is not only for the benefit of sustainable construction and disposal of industrial waste but also for the reduction of CO2 emissions due to the increasing production of Portland cement from the cement production industry. A laboratory investigation was carried out on the workability and mechanical properties of geopolymer paste and mortar produced with alum sludge replacement in different proportions (0, 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100). A combination of an alkaline solution of sodium silicate and sodium hydroxide of 14 molarity was employed as an activator for the manufacturing of both paste and mortar geopolymer specimens. It was observed from the findings that geopolymer paste and mortar was flowable and workable when alum sludge is replaced for fly ash at higher replacement content. The addition of alum sludge to the mix improved some properties such as density, strength, water absorption, and the elevated temperature behavior. It was observed that the addition of alum sludge was optimum at the 50% replacement level. The addition of alum sludge up to 50% significantly increased the compressive strength of mortar (up to 80% increase in 28 days strength). The compressive strength of the paste and mortar increased with an increase in curing age. Thus, alum sludge and fly ash can be employed together in the production of eco-friendly cementing material for environmental sustainability.

Mechanical properties and microscopic mechanism of active MgO-fly ash solidified saline soil in seasonal freezing areas

This paper presents an innovative method for improving the strength of salt-bearing clay under freeze–thaw cycles. The active magnesium oxide (MgO) and industrial waste fly ash were employed as primary solidifying materials in the seasonal freezing soil reinforcement process, and the reinforcement effect is achieved through carbonate crystals generated through carbonization tests. The solidification effect was investigated with varying ratios of solidifying materials, salt content, and freeze–thaw cycles. The experiment results revealed that the combination of active MgO and fly ash effectively enhances the strength of salt-bearing clay. Specifically, compared to unsolidified soil, the soil solidified with 8 % active MgO (8M0F) and a combination of 4 % active MgO and 4 % fly ash (4M4F) demonstrated a significant increase in ultimate strength by 14 and 12 times, respectively. Moreover, the number of freeze–thaw cycles exhibited a negative correlation with ultimate strength, whereas the salt content demonstrated a similar negative correlation. Microscopic analysis revealed that the 8M0F sample produced mainly magnesium carbonates and hydrogen and oxygen compounds, whereas the 4M4F sample generated primarily magnesium and calcium carbonates. The resulting compound crystals efficiently filled the internal pores and cemented the soil particles, leading to a substantial increase in strength. Overall, these results indicate that the active MgO combined with fly ash solidifying method can offer a viable and sustainable solution for improving the strength of salt-bearing clay in areas with seasonal freeze–thaw cycles.

Synergic Effects of Nano Additives on Mechanical Performance and Microstructure of Lightweight Cement Mortar

Owing to their convenient manufacture, transportation, low energy consumption, and environmental impacts, lightweight cement composites have been applied as building and construction materials. However, its decreased density is associated with a reduction in mechanical strength. In most existing investigations, attempts have been made to improve mechanical behaviours via supplementary cementitious or fibre materials, whereas limited studies have been implemented on the effects of nano additives, especially their synergic influence. In this study, industrial waste fly ash cenosphere (FAC) has been utilized as lightweight aggregate by 73.3% cement weight to fabricate sustainable lightweight cement mortar (LWCM). Carbon nanotubes (CNTs) at a dosage of 0.05%, 0.15%, and 0.45% and nano silica (NS) with the content of 0.2%, 0.6%, and 1.0% by cement weight have been applied as modifying additives. Experiments were carried out to test flexural strength, compressive strength, and water absorption. SEM, TG, and XRD analyses were conducted to evaluate microstructure and hydration characteristics. Based on the outcomes, the inclusion of CNTs and NS can effectively increase flexural and compressive strength and reduce absorbed water weight. The analysis of SEM, TG, and XRD reveals that the binary usage of CNTs and NS can improve pore structure and facilitate hydration reaction.

Valorization of industrial siliceous wastes in the production of geopolymers binders

To develop a practical alternative to classic cement materials, alkali-activated materials were manufactured from industrial wastes (fly and bottom ash). Microstructural behavior of these blends was investigated through X-ray diffraction, scanning electron microscope, thermal analysis, Fourier-transform infrared spectroscopy and surface response methodology. Natrolite, phillipsite, and calcium aluminum silicate hydrate and sodium carbonate newly formed after alkali activation. Empirical ternary diagrams as well as modeling equations were united to predict the physico-mechanical evolution of the prepared specimens. The used model described well the evolution of the studied properties against the processing factors; temperature, NaOH concentration and curing time. The weight of the effect of each parameter was estimated and factor to factor interaction was considered. NaOH concentrations and ageing temperature had a considerable positive effect on density and mechanical strength, respectively. Water absorption and electrical conductivity were influenced differently by the factors, the electrical conductivity increases as the NaOH concentrations increase, and time and temperature decrease. The response surfaces and their results were correlated with the microstructure of the hardened samples. Overall, alkali activated binders with good engineering properties could be synthesized in the considered conditions. The optimal alkali activation conditions were ∼12 M and the corresponding final properties were as follows: 50 MPa for the compressive strength and 20% for water absorption while density was recorded at a 1.75 g/cm3 value.

Preparation and Properties of Double Liquid Grouting Materials (DLGMs) Used for the Regenerated Roof of a Coal Mine

Double liquid grouting materials (DLGMs) are composed of slurry A and slurry B. In response to the need for sustainable development, there is currently a focus on improving the utilization rate of resources. In this paper, industrial solid waste fly ash, slag, and ordinary Portland cement were used to prepare slurry A, while sodium silicate was used as slurry B. Slurry C was made by adding slurry B to slurry A. The mix design parameters of the DLGMs, with large amounts of fly ash, were optimized based on the response surface method. The results showed that the relative content of cement and the reactivity and morphological effect of supplementary cementitious materials (fly ash and slag) were the main factors affecting the operable time, viscosity, and stability of slurry A. The relative content of cement and the sodium silicate modulus were the main factors affecting the operable time of the DLGMs. Compared to the C30F70S0-Z3.3 group (where C, F, S, and Z represented cement, fly ash, slag, and sodium silicate modulus, respectively), the operable time of the C0F70S30-Z3.3 group increased by approximately 36 min. As the sodium silicate modulus was lowered to 2.3, the operable time of the C0F70S30-Z2.3 group increased by about 32 min compared to that of the C30F70S0-Z2.3 group. The established model and response surface can well reflect the influence of multiple factors on the properties of the DLGMs. When the mass ratio of cement/fly ash/slag in slurry A was 7.5%: 70%: 22.5%, and the sodium silicate modulus and content of slurry B were 2.8 and 10%, respectively, the 28-day compressive strength of the DLGMs can reach up to 11.3 MPa. The content of fly ash was the most significant factor affecting the 28-day compressive strength of the DLGMs, followed by the sodium silicate content. The least influential factor was the sodium silicate modulus. The XRD and SEM results showed that a large amount of Ca2+ produced by cement hydration can quickly react with [SiO4]4- in sodium silicate to form C-S-H gel. Moreover, it also promoted the hydration of C3S and C2S in grouting to produce more C-S-H gel, which was conducive to the alkali activation of slag and fly ash, resulting in a denser microstructure and hence, yielded obvious increases in the compressive strengths of the DLGMs.