Cementitious Material In Concrete Research Articles

Research Progress on the Activity Stimulation of Lithium Slag in Concrete

Lithium slag (LS), an industrial waste byproduct generated during lithium salt production, is characterized by its harmful trace elements, significant stockpiles and low pozzolanic activity. By 2003, the annual discharge of lithium slag in China surpassed 15 million tons, creating an urgent need for established large-scale disposal technologies. One of the primary strategies for the effective utilization of LS is its application as an auxiliary cementitious material in concrete. However, the low reactivity of LS and challenges associated with its large-scale application impede its effective utilization. Enhancing the pozzolanic activity of LS is pivotal for its substantial incorporation into concrete. This study begins by analyzing the physicochemical properties and volcanic ash reactivity of LS derived from various lithium extraction techniques. It subsequently explores the diverse activation techniques aimed at improving the reactivity of LS within concrete. Ultimately, this paper highlights the significance of synergistic activation strategies, particularly physicochemical co-excitation and multi-exciter composite excitation. These approaches are identified as critical pathways for enhancing the activity of LS. Through this exploration, this study aims to unveil innovative strategies that bolster the resource utilization efficiency of LS, thereby facilitating its effective application in the concrete domain.

Assessing the Usage of Barytes Powder and Cuddapah Stone Dust as Supplementary Cementitious Materials in Concrete of Grade M30 and M35

This research studied the effects of using Barytes powder and Cuddapah stone waste as substitutes for cement in M30 and M35 grade concrete using OPC. Cement production is known to harm the environment and consume a lot of energy, making the search for alternative materials to replace cement in concrete important.In this study, different amounts of Barytes powder and Cuddapah stone waste were added to concrete mixes as partial replacements for cement. The resulting concrete was tested for compressive strength and compared to normal concrete. The experiment involved making concrete samples with varying percentages of cement replacement, ranging from 0% to 50%, using Barytes powder, Cuddapah stone waste and Combination. The samples underwent standard curing and testing according to Indian standards.The research analysed the results to find the optimum percentage of cement replacement that provided satisfactory mechanical properties. This study determined the feasibility and effectiveness of using Barytes powder and Cuddapah stone waste as partial replacements for cement in concrete production.

Strength, durability, and heat development characteristics of high-performance concrete containing ground coal bottom ash with low and high calcium

Currently, the availability of fly ash has reduced continuously due to the shutdowns of coal-fired power generating plant as climate change concerns have increased. Therefore, the aim of this paper is to find an alternative pozzolan by examining the employment of low- and high-calcium oxide (CaO) ground bottom ash which has been abandoned rather using in concrete production. The bottom ashes were blended with fly ash as a partial substitution of cement (OPC) by observing their generic effects on the compressive strength, cumulative heat generation, chloride ion penetration, and water sorptivity of high-performance concrete. The samples of bottom ash were prepared by oven drying, particle size cutting, and grinding to enhance the reactivity and consistency. High-performance concretes were made at a water-to-binder (W/B) ratio of 0.27 and partial replacement of OPC up to 50 % by weight of the binder. The results indicated that the concretes with 28-day compressive strengths of 101.0 and 109.0 MPa (21.6 % and 28.2 % stronger than OPC concrete) were produced with 50 wt% OPC replacement with high- and low-calcium ground coal bottom ashes (HCBA and LCBA), respectively. These findings suggest that HCBA and LCBA have high pozzolanic reactivity and high possibility for utilization as pozzolan or supplementary cementitious materials in concrete. In addition, the binary blended binders (OPC-HCBA and OPC-LCBA) and ternary blended binders (OPC-HCBA-FA and OPC-LCBA-FA) produced had better chloride ion penetration resistance, less cumulative heat evolution, and lower water sorptivity than 100 % OPC as a cementitious material. Partial OPC replacement by HCBA and LCBA improved the chloride ion penetrability class of OPC concrete from “very low” to “negligible.” The cumulative heat generation due to the pozzolanic reaction of HCBA and LCBA from the partial replacement of OPC up to 50 % reduced 30–44 % relative to the OPC-based mixture throughout during 72 hours after mixing. The CaO content strongly influenced early compressive strength development and cumulative heat evolution but had less impact on chloride ion penetration resistance and water sorptivity.

Development of a Superhydrophobic Protection Mechanism and Coating Materials for Cement Concrete Surfaces.

In order to further enhance the erosion resistance of cement concrete pavement materials, this study constructed an apparent rough hydrophobic structure layer by spraying a micro-nano substrate coating on the surface layer of the cement concrete pavement. This was followed by a secondary spray of a hydroxy-silicone oil-modified epoxy resin and a low surface energy-modified substance paste, which combine to form a superhydrophobic coating. The hydrophobic mechanism of the coating was then analysed. Firstly, the effects of different types and ratios of micro-nano substrates on the apparent morphology and hydrophobic performance of the rough structure layer were explored through contact angle testing and scanning electron microscopy (SEM). Subsequently, Fourier transform infrared spectroscopy and permeation gel chromatography were employed to ascertain the optimal modification ratio, temperature, and reaction mechanism of hydroxy-silicone oil with E51 type epoxy resin. Additionally, the mechanical properties of the modified epoxy resin-low surface energy-modified substance paste were evaluated through tensile tests. Finally, the erosion resistance of the superhydrophobic coating was tested under a range of conditions, including acidic, alkaline, de-icer, UV ageing, freeze-thaw cycles and wet wheel wear. The results demonstrate that relying solely on the rough structure of the concrete surface makes it challenging to achieve superhydrophobic performance. A rough structure layer constructed with diamond micropowder and hydrophobic nano-silica is less prone to cracking and can form more "air chamber" structures on the surface, with better wear resistance and hydrophobic performance. The ring-opening reaction products that occur during the preparation of modified epoxy resin will severely affect its mechanical strength after curing. Controlling the reaction temperature and reactant ratio can effectively push the modification reaction of epoxy resin through dehydration condensation, which produces more grafted polymer. It is noteworthy that the grafted polymer content is positively correlated with the hydrophobicity of the modified epoxy resin. The superhydrophobic coating exhibited enhanced erosion resistance (based on hydrochloric acid), UV ageing resistance, abrasion resistance, and freeze-thaw damage resistance to de-icers by 19.41%, 18.36%, 43.17% and 87.47%, respectively, in comparison to the conventional silane-based surface treatment.

Principles for Incorporating Recycled Materials into Airport Pavement Construction for More Sustainable Airport Pavements

Current international waste policy promotes the reduction and re-use of waste materials, and in some cases, specifically calls for the use of recycled materials in pavements. Consequently, there is a need to understand the performance of recycled materials in airport pavements, as well as the overall sustainability benefit. This paper reviews several recycled materials and their applications to asphalt concrete, cement concrete, and bound and unbound granular materials in the context of airport pavements. Additionally, it reviews sustainability quantification methods, as well as implementation challenges for using recycled materials in airport pavements. For comparing pavements with and without recycled materials, a triple bottom line approach is appropriate. The triple bottom line approach should use life cycle cost assessment and life cycle assessment for the financial and environmental impacts, respectively, as best-practice, with frameworks and guidelines already established. For social impacts, it is recommended to quantify the reduction in virgin material use which relates to intergenerational equity by ensuring access to materials by future generations. Because there are still implementation challenges for the airport pavement industry, principles are developed that aim to promote uptake of recycled materials. These principles include sorting and processing, minimising haulage distances, and ensuring performance of pavement layers through performance testing and performance-related specifications.

Technical, economic, and environmental feasibility of rice hull ash from electricity generation as a mineral additive to concrete

A circular economy based on symbiotic relationships among sectors, where the waste from one is resource to another, holds promise for cost-effective and sustainable production. This research explores such a model for the agriculture, energy, and construction sectors in California. Here, we develop new an understanding for the synergistic utilization mechanisms for rice hull, a byproduct from rice production, as a feedstock for electricity generation and rice hull ash (RHA) used as a supplementary cementitious material in concrete. A suite of methods including experimental analysis, techno-economic analysis (TEA), and life-cycle assessment (LCA) were applied to estimate the cost and environmental performance of the system. TEA results showed that the electricity price required for break even on expenses without selling RHA is $0.07/kWh, lower than the market price. As such, RHA may be available at little to no cost to concrete producers. Our experimental results showed the viability of RHA to be used as a supplementary cementitious material, meaning it can replace a portion of the cement used in concrete. LCA results showed that replacing 15% of cement with RHA in concrete can reduce carbon dioxide equivalent (CO2e) emissions by 15% while still meeting material performance targets. While the substitution rate of RHA for cement may be modest, RHA generated from California alone could mitigate 0.2% of total CO2e from the entire cement production sector in the United States and 1% in California.

A COMPREHENSIVE REVIEW OF THE USE OF NEUTRAL CARBON AND BIO-OIL WASTES ON WARM MIX ASPHALT CONCRETE

Waste materials can be used to produce cement concrete, asphalt concrete, block concrete, and other construction materials. This has been known for more than 30 years in the field of civil engineering. To allay ecological concerns, several nations are currently researching the reprocessing of neutral carbon and bio-oil wastes (NC&BoWs). These wastes are sustainable, but because of their large volume of landfill disposal, which has detrimental effects on the ecosystem and its inhabitants, they are starting to become quite worried for the ecosystem. Therefore, this study provides a comprehensive review of the use of NC&BoWs on warm mix asphalt (WMA) concrete to lessen our worries about the environment. Numerous investigations have been conducted to enhance various WMA technologies. These three technologies such as foaming, chemical, and organic enhance the structural behavior of WMA concrete and lower the viscosity of the asphalt binder. A bibliometric analysis shows that only 26 out of the 168 articles related to this study were published by Scopus between 2012 and 2023. Full-length articles accounted for 100.0% of Scopus publications, and it seems that not a single review article was accepted and published by Scopus. Based on the subject area, the fields of engineering, materials sciences, and physics and astronomy published 50.0%, 43.5%, and 6.5% of the Scopus articles, respectively. Consequently, the findings suggested that further reviews are necessary to verify NC&BoWs' ongoing efficacy in WMA concrete

Process optimization of acq-polyacrylate modified bamboo aggregate and durability analysis of all-bamboo aggregate concrete

All-Bamboo Aggregate Concrete (BAC) is a type of cement concrete material where all coarse aggregates are made of bamboo aggregate, a plant material that requires necessary measures to avoid or slow down its degradation in alkaline and natural environments. This paper enhances the durability of BAC materials through the treatment of bamboo aggregate with ACQ-polyacrylate (AP method). Initially, the study explores the impact of polyacrylate dilution concentration on the compressive strength and coating thickness of BAC, and based on a reasonable modification process, conducts freeze-thaw cycles, salt solution immersion, accelerated wet-dry aging, and long-term natural environment tests to assess the durability of BAC materials. The results show that a polyacrylate solution with a dilution ratio of 1:5 can form a coating thickness of 23.8μm, performing better in various durability evaluations. After 25 freeze-thaw cycles, the BAC material's loss rate of compressive strength is lower than that of Ordinary Concrete (OC). Compared with OC, BAC materials are more susceptible to salt damage after salt solution immersion. The compressive strength loss rate under 180 days of natural environment exposure is comparable to that in 10 cycles of accelerated wet-dry aging, 28 days of salt solution immersion, and 10–15 freeze-thaw cycle tests, recommending the use of freeze-thaw cycle tests for evaluating the durability of BAC materials from an experimental efficiency perspective. By exploring the durability of BAC materials, this paper provides an innovative solution in the field of construction materials, promoting the transition of the construction industry towards sustainable development. It emphasizes the feasibility and effectiveness of improving the performance of bamboo-based materials through surface treatment technology, offering a valid reference for developing more environmentally friendly and high-performance new materials in the future.

Gelatin‐based air‐entraining agents for ordinary portland cement: Chelate Ca2+ and reduce surface tension

AbstractIntroducing uniform, stable, and small pores by adding air‐entraining agents (AEAs) is an effective strategy for improving the freeze–thaw resistance and workability of cement concrete materials. In this study, the gelatin with hydrophobic and hydrophilic functional groups was used as an AEA for cement concrete materials and systematically studied its effect on the performance of cement mortar specimens. The results showed that gelatin has a surfactant‐like function and can effectively reduce the surface tension of the gas–liquid interface. In an alkaline environment, Ca2+ ions in cement pore solution chelate with carboxylate ions formed by carboxyl ionization, further enhancing the performance of gelatin‐based AEAs. Thanks to the reduction in surface activity and carboxyl ionization, introducing gelatin increased the porosity of cement mortar specimens from 0.53% to 2.69%. Furthermore, introducing an appropriate amount (>0.1 wt%) of gelatin does not significantly impact the workability or mechanical properties of cement mortar. Based on these characteristics, gelatin has potential as an AEA for cement concrete materials.

Reliability Analysis of Compressive Fatigue Life of Cement Concrete under Temperature Differential Cycling

Cement concrete, as an extensively used engineering material, is omnipresent in various infrastructure projects such as bridges and roads. However, these structures often need to operate for extended periods under varying and harsh environmental conditions, facing not only complex vehicular loads but also the effects of temperature differential cycling. Consequently, understanding how temperature differential cycling impacts the compressive fatigue life of cement concrete has become a pivotal research topic. In this study, through a comprehensive experimental design, the fatigue life of cement concrete under typical temperature difference conditions (20–60°C) and different number of temperature differential cycling (60, 120, 180, 240, 300) was tested at three stress levels (0.70, 0.75, 0.85). Statistical analysis was conducted to obtain the Weibull distribution parameters of the compressive fatigue life of cement concrete. The Pf–S–N relationship of concrete considering reliability was analyzed, and a fatigue life prediction model under different reliability probabilities was established. The results show that the fatigue life of concrete subjected to temperature differential cycling follows a two-parameter Weibull distribution well. From the Pf–N curve, it can be seen that, regardless of the stress level, the calculated fatigue life under the same reliability probability decreases with the increase of temperature differential cycling times. At a 95% reliability probability, the decrease can reach 77.5%–87.5%. Based on the exponential function, a concrete fatigue life prediction model based on different reliability levels was established. Using this model, the S–lgN curve was plotted, and it was found that, regardless of the temperature differential cycling, an increase in reliability probability could lead to a 7.3%–14.4% reduction in logarithmic fatigue life (lgN). Additionally, this study also defined a fatigue life safety factor related to the number of temperature differential cycling and reliability probability, aiming to provide a theoretical basis for the design of cement concrete materials under the coupled environment of temperature differential cycling and fatigue loading.

Mechanical properties and microstructure of waterborne polyurethane-modified cement composites as concrete repair mortar

With the increase in service life, the durability of a large number of concrete structures deteriorates year by year under the influence of the external environment, requiring urgent repair and reinforcement. Ordinary cement concrete materials have disadvantages such as high brittleness, low tensile strength, poor bonding ability, and insufficient durability, making it difficult to meet the repair needs of high-quality building structures. Therefore, self-synthesized anion WPU was used to study its effect on the mechanical properties of cement-based repair mortar. The research found that waterborne polyurethane (WPU)-modified cementitious composite repair materials exhibit better bonding strength with old concrete substrates compared to traditional cement-based materials. Additionally, the incorporation of WPU significantly reduces the brittleness of the repair material, ensuring enhanced efficiency in the repair process. However, according to the hydration heat test results, the addition of WPU delays the hydration process of the composite repair materials. In addition, the addition of WPU enhances the flexibility and bonding ability of the materials, with flexural strength and tensile strength at the age of 28 days reaching 13 MPa and 6 MPa, respectively. Through stress‒strain curve analysis, it was found that the maximum strain amplification of WPU cement mortar can reach 134 %. Combined with SEM testing, it was observed that cured WPU films were present in specimens aged 28 days with P/C ratios of 10 % and 15 %. WPU and cement hydration products permeate each other, forming a three-dimensional polymer network structure, improving the pore structure, and fully exerting the flexibility of WPU. This also validates the experimental results of increased ultimate tensile strain. WPU cement-based composite repair materials have higher bonding strength at a high P/C ratio (15 %), and WPU alone, used as an interface agent for pretreating the interface of old concrete, can improve the interface bonding strength, up to twice that of the group without the surface agent.

Effect of Marble Dust Powder on the Properties of Fresh and Hard Concrete

The goal is to investigate the potential for employing byproducts from various industrial processes in the creation of ground-breaking mortar and concrete. The dust produced during the marble-cutting operation is put to good use. Different percentages of this garbage were recommended to be used in conjunction with or in place of cement in the making of concrete. The research looked into the possibility of using marble dust, which is produced during the shaping of marble blocks, as a cementitious material in concrete. In areas where they are readily available and can reduce construction costs, the study found that dust from marble slabs could be employed as a cementitious material in concrete mixtures. The discarded marble dust is mixed with cement in proportions of 5, 10, 15, and 20% of the standard concrete mix. Both the fresh and hardened characteristics of the produced combinations were investigated. Compressive and tensile strengths were measured after being cured for varying periods of time, both when marble dust was used as a partial replacement and when it was not.

SHOTCRETES AND MORTARS FOR 3D PRINTERS USING CHINESE INDUSTRIAL WASTE

Currently, ordinary Portland cement is the main cementing material for shotcrete in tunnels in my country. Part of the use of single-doped silica fume or fly ash, however, there are few cementitious materials that use double-doped or multi-doped mineral admixtures. Due to the single composition of the cementitious material, poor gradation, and low quality, the concrete has poor compactness, insufficient viscosity, and large rebound. The use of "multiple" mineral admixtures can better solve the problem of high rebound rate of shotcrete in tunnels. Among them, mineral admixtures include mineral powder, fly ash, silica fume and limestone powder. The cementitious material in concrete can be single-mixed, double-mixed or multi-mixed with mineral admixtures. In this way, the heat of hydration when the concrete sets and hardens can be reduced, reduce the cracking of concrete, improve the compactness and viscosity of concrete and reduce the rebound rate of concrete.
 The aim of research: the overall idea and technical measures to solve the high rebound rate of shotcrete or 3D printer mix and the high amount of cementitious materials using Chinese industrial waste.
 Scientific novelty of research: optimal compositions using Chinese industrial waste for wet shotcrete, optimal compositions using Chinese industrial waste for 3D construction printers, basic properties of wet shotcrete composites with using Chinese industrial waste, basic properties of 3D construction printer composites with using Chinese industrial waste.

Sugarcane Bagasse-Derived Carbon for Partial Replacement of Cementitious Material in Concrete

Sugarcane Bagasse-Derived Carbon for Partial Replacement of Cementitious Material in Concrete

Exploring the resilience of supplementary cementitious materials-based concrete to elevated temperatures via modern computing techniques

Researchers are focused on the production of sustainable materials in order to reduce the negative environmental impact of conventional concrete. Utilizing industrial by-products as alternative cementitious materials in concrete is an appropriate strategy for promoting sustainability in construction. This research employed supervised machine learning techniques, including gradient boosting (GB), random forest (RF), and extreme gradient boosting (X-GB), in order to predict the compressive strength of sustainable concrete when exposed to high temperatures. SHapley Additive exPlanation (SHAP) analysis provided input component relevance. The comparison of these methodologies indicated that X-GB performed remarkably well and had a superior R2 value of 0.94 when compared to GB and RF. The results were further supported by a Taylor diagram, which demonstrated that the X-GB model best fitted the data, surpassing both the GB and RF models. This study's findings demonstrated the potential of machine learning, and more particularly X-GB, for making accurate predictions of compressive strength in high-temperature concrete applications. The results of SHAP analysis may be useful for selecting the proportions of raw materials in the mix design to achieve the desired properties.

Experimental investigation and modelling of the mechanical properties of palm oil fuel ash concrete using Scheffe’s method

This study explores the enhancement of mechanical properties in concrete blended with palm oil fuel ash (POFA) through Scheffe's optimization. The utilization of POFA as supplementary cementitious material in concrete has gained attention for its potential environmental benefits. Utilizing a (5,2) simplex-lattice design, a systematic approach is employed for optimizing mixture proportions based on response parameters. The laboratory tests to evaluate concrete's mechanical behavior were conducted using the computed mixture ratios from the design experimental points after 28 days of hydration. The results showed maximum flexural strength at 8.84 N/mm2 and compressive strength at 31.16 N/mm2, achieved with a mix of 0.65:0.54:2.3:3.96:0.35 for cement, water, coarse aggregate, fine aggregate, and POFA. Additionally, maximum splitting tensile strength reached 8.84 N/mm2 with a mix of 0.62:0.55:2.09:3.86:0.38 for the same components. Conversely, the minimum flexural, splitting tensile and compressive strength within the experimental factor space was 4.25, 2.08 and 19.82 N/mm2 respectively. The results obtained indicated a satisfactory mechanical strength performance at POFA replacement of 35 percent in the concrete mixture. The developed mathematical model was statistically validated using analysis of variance (ANOVA) at a 95% confidence interval which showed satisfactory prediction performance. The findings from this study provide valuable insights into optimizing POFA-blended concrete for enhanced mechanical performance, offering potential sustainable solutions for the construction industry.

ВНУСТРІШНЬОСТРУКТУРНІ ТЕРМОНАПРУЖЕННЯ В АСФАЛЬТОБЕТОННИХ І ЦЕМЕНТОБЕТОННИХ МАТЕРІАЛАХ, ПІДСИЛЕНИХ ФІБЕРГЛАСОВОЮ, ФІБЕРКАРБОНОВОЮ, ФІБЕРБАЗАЛЬТОВОЮ ТА ФІБЕРАРАМІДНОЮ АРМАТУРОЮ

By the methods of mathematical modeling, the internal structural thermomechanical effects that are blamed on asphalt concrete and cement concrete materials, reinforced with the fiberglass, fibercarbon, fiberbasalt and fiberara-mide strands, are investigated under conditions of change the temperature of the system. The analysis of the thermome-chanical incompatibility of the phases of the composites with the aim of establishing its influence on the values of the internal structural thermal stresses, which are attributable to these changes, is performed. It is shown that for the as-phalt concrete material the incompatibility is small and so the system internal structural thermal stresses are also small and do not exceed the values of the limit strength of the fractions of the composite material. For composites with a cement concrete matrix, the thermomechanical incompatibility of their fractions is essential and for this reason the ther-mal stresses, which are due to the temperature change, significantly exceed the values of the limit strength of the cement concrete. The established features may be used during the design of reinforced road pavements and cement concrete structures, which work under conditions of changing temperatures. Keywords: composite materials, reinforced concrete, epoxy coating, corrosion damage, thermomechanical incompati-bility, thermal stress.

Effect of high temperature modification on the highly adsorptive manufactured sand dust concrete

The production process of manufactured sand generates a large amount of dust, which poses a serious threat to the environment. In this study, we selected highly adsorptive manufactured sand dust of three lithologies (diabase, tuff, and basalt) for high temperature calcination. We evaluated its mechanical properties and microstructures after high temperature modification using various characterization methods to investigate its feasibility as a supplementary cementitious material (SCM). A comparative analysis of the manufactured sand dust before and after modification was conducted using thermogravimetric-differential scanning calorimetry (TG-DSC), laser particle size analysis, X-ray diffraction (XRD) and X-ray fluorescence spectrometry (XRF) techniques, the results showed that high temperature modification can reduce the crystallinity of the mineral impurities in the manufactured sand dust. Furthermore, the average particle size of artificial sand dust from all three lithologies (diabase, tuff, and basalt) was reduced. However, the flowability of the mortars increased by 12.1%, 7.4%, and 6.4% respectively. The 28-day volcanic ash activity index reached 63%, 61%, and 60% respectively. In addition, we used the modified manufactured sand dust as a supplementary cementitious material in concrete. It was found that when 30% of cement was replaced with a 1:2 mixture of manufactured sand dust and fly ash, the compressive strength at 90 days reached a maximum of 90.6 MPa. These results demonstrate that the modified manufactured sand dust has certain economic benefits and can be used to partially replace cement in concrete. This provides a basis for the development and application of highly adsorptive manufactured sand in the long term.

Thermomechanical Aspects of Frost Resistance of Cement and Asphalt Concrete Materials

Thermomechanical Aspects of Frost Resistance of Cement and Asphalt Concrete Materials

Performance of cement-based materials incorporating ultra-fine copper slag

The application of copper slag (CS) as a supplementary cementitious material in concrete is unsatisfactory due to the fact that CS is mainly composed of fayalite. The dissolution kinetics of fayalite determines the pozzolanic activity of CS. How to improve the dissolution of fayalite is a challenge for CS resource utilization. To address this issue, ultra-fine CS with different fineness was fabricated by wet-grinding method for the first time in this work and the performance of cement-based materials incorporating ultra-fine CS was assessed. Results revealed that an increase in CS fineness significantly promoted the decomposition of fayalite to improve the mechanical strength of mortars. The 7 d and 28 d strength activity index of ultra-fine CS can reach 106% and 102%, respectively, which has seldom been reported in the literature. Although ultra-fine CS can significantly accelerate the hydration process at the very beginning of reaction to form more hydrates, the early-age pozzolanic activity was still not ideal. The prepared ultra-fine CS exhibited good later-age pozzolanic activity, which can consume more portlandite and generate more hydrates, resulting in a denser microstructure. These results indicated that ultra-fine CS can be used as a high-quality alternative cementitious material to improve the greenness of cement and concrete products.