Optimal Ratio Research Articles

Effect of dual flocculant by unmodified manihot esculenta starch and aluminium sulphate on the removal of chemical oxygen demand optimized by response surface methodology

Abstract Applying inorganic metal salt-based aluminium sulphate (Al2(SO4)3) or alum in wastewater treatment has gained many concerns regarding the impact on health and environmental implications. Due to the negative consequences, incorporating inorganic and natural flocculants in the coagulation-flocculation process is the alternative way to reduce undesirable effects. In this study, an evaluation performance of Manihot esculenta (ME) starch and alum as a dual flocculant was conducted to remove chemical oxygen demand (COD) in the optimum weight ratio of alum/starch = 0.06. The optimization of coagulation-flocculation by the optimal (custom) design, response surface methodology (RSM) presented that applying a dual flocculant improved the COD removal efficiency by up to 93% compared to a single coagulant (alum) of 85%. Besides the performance of COD removal increased, the dosage of the chemical coagulant was reduced by up to 64% at the optimum condition of 18 mg/L alum dosage, 307 mg/L starch dosage, pH 9, and 27 mins settling time. The analysis of variance (ANOVA) indicated that the quadratic model was significantly developed with a p-value < 0.05. The results were justified by a high coefficient of determination (R2 alum = 0.9641) and (R2 dual flocculants = 0.9335) using single and dual flocculants, respectively. The findings supported ME starch as an alternative approach in minimizing chemical coagulants in wastewater treatment.

The Influence of Different Mass Ratios on Vortex-Induced Vibration Energy Extraction of Four Cylinder Arrays

Currently, there is a growing demand for renewable energy harnessed from fluid dynamics within the oil and gas industry. The surge in demand has propelled electricity to become a vital and irreplaceable form of universal energy worldwide. Vortex-Induced Vibrations (VIV) energy harvesting shows great potential as a technology for capturing energy from flowing bodies of water. The purpose of this research is to investigate the numerical aspect of VIV in rigid circular cylinders with the intention of capturing renewable energy from the sea. The investigation employs a Vortex-Induced Vibration Aquatic Clean Energy (VIVACE) converter to analyze the vibration characteristics of densely packed cylinders featuring varying mass ratios (m*) at both minimum and maximum values. Another purpose of the study is to investigate the effect that m* has on the performance of a VIV converter that is comprised of four cylinders positioned in a staggered pattern. For the purpose of analyzing power conversion in the VIV energy converter model across a wide range of mass ratios (from 2.36 to 12.96), simulations are carried out with a Reynolds number of 82000. The findings indicate that the highest converted power reaches a peak of 7.48 W with a mass ratio of 2.36, whereas a greater mass ratio of 12.96 results in only 4.33. The study highlights the substantial influence of mass ratios on the extraction of power output from VIV. The results essentially offer crucial information about the optimum mass ratio in closed four cylinder arrays to design VIV energy harvesting to produce clean and renewable energy sources.

The change of physical properties of calcium carbonate nanomaterials cured soil in road substrates

The utilization of appropriate materials to enhance road subgrade’s physical characteristics is crucial for current transportation construction and maintenance. This study proposes a curing method that employs calcium carbonate nanomaterials to address the problem of soil displacement and settlement in roadway subgrades. A method was developed during the study to explore the optimal curing material ratio. Additionally, this study developed a method for testing and analyzing the mechanical properties of soils cured with nanomaterials, including measures of tensile stress, triaxial shear stress, and Moore’s damage envelope. The study demonstrated that the unconfined compressive strength of the soil treated with calcium carbonate nanomaterials was 0.40 MPa after 7 days of curing with a 6% doping of the curing agent. Increasing the doping to 18% resulted in a breaking load of the soil reaching 0.100 kN. Furthermore, the triaxial shear stress–strain curve of the soil exhibited a slope of 264.47 during the linear phase when the curing agent was dosed at 6%. The slope of the linear phase of the stress–strain curve for triaxial shear at 6% curing agent doping was found to be 264.47. The cured soil molar pack line exhibited an internal friction angle of 22.66 degrees at the same curing agent dosage. The displacement analysis of the replacement roadbed with cured soil revealed a maximum observed displacement of only 377 mm after filling the embankment using the study method. The experimental results provide support for the hypothesis of the study, which suggests that the application of calcium carbonate nanoparticles can significantly enhance the physical characteristics of road subgrade.

Meta model-based optimization of jacket offshore platform for resilient marine infrastructures

Abstract Marine infrastructure is an established sector in the blue economy of Indonesia and is expected to shift from a project to a product-based approach. At the same time, the development of the blue economy depends on the economic value that needs to cut down the construction cost for marine infrastructure. To realize this development plan, a structural design optimization framework must be initiated to design a more resilient and high-economy value infrastructure. Marine infrastructures in Indonesia are dominated by jacket-type structures suitable for shallow water. A study of design optimization for jacket-type offshore structures is conducted in this paper. The structure is designed for the Indonesia Sea, located in North Gresik. The optimization is conducted with the structure limit state as the constraint as a meta-model. Variables are the dimensions of structural main members, consisting of the tubular member radius and thickness. The highest optimization ratio is achieved for the wall thickness variable. The cost objective and computational effort reduction prove the feasibility of the proposed design optimization method.

Employment of the DCC-GARCH Copula Model to explore a link between robotics and artificial intelligence and green crypto investments.

The pursuit of the Sustainable Development Goals (SDGs) requires considerable new green crypto investments. To attract the flow of this investment, it is necessary to develop and apply robotic artificial intelligence (AI) as it has the potential to encourage the adoption of environmental innovation and increase individuals' environmental awareness. Our research employs the DCC-GARCH Copula Model to examine time-varying spillovers and prove interlinkages between the development of AI and green cryptocurrencies in the period from January 1, 2018, to September 8, 2023. Comparing the optimum hedge ratios with the optimal portfolio weights, we demonstrate that the optimal hedge strategy for BOTZ is the most successful one. However, the success of hedging depends on the portfolio's risk profile. Based on our analysis of the cumulative profit profile of different approaches, we continue to believe that the best portfolio weighting strategy is the one that produces positive returns in the middle of 2020 and the first part of 2022 and 2023. This demonstrates that the most profitable diversification approach is not always the most successful one. Our results have important policy implications for investors and governments.

Experimental investigation of mechanical properties and multi-objective optimization of electronic, glass, and ceramic waste-mixed concrete.

The utilization of waste from various sources plays an important role in minimizing environmental pollution and civil construction costs. In this research, the mechanical properties of concrete were studied by mixing electronic waste (EW), glass powder (GW), and ceramic tile waste (CW). The effects of weight percentages of EW, GW, and CW are considered to investigate improvements in mechanical properties such as compressive strength (CS), split tensile strength (STS), and flexural strength (FS) of concrete. Taguchi analysis has been applied to predict the optimum composition of waste mixing percentages. The Multi-Objective Optimization Ratio Analysis (MOORA) techniques are applied to estimate the optimum composition of mixing wastes for maximizing the CS, STS, and FS of concrete. It was observed that 10 wt.% of EW, 15 wt.% of GW, and 30 wt.% of CW are predicted as the optimal mixing combinations to obtain a maximum compressive strength of 48.763 MPa, a split tensile strength of 4.178 MPa, and a flexural strength of 7.737 MPa, respectively. Finally, the predicted optimum waste-mixed weight percentages were used to examine the microstructure and various elements in the concrete using SEM and XRD analysis. When compared to conventional concrete, the optimum waste-mixed concrete has improved its compressive strength (38.453%), split tensile strength (41.149%), and flexural strength (36.215%).

Flexible metal–organic frameworks based self-lubricating composite

To expand the use of metal–organic frameworks (MOFs) based self-lubricating composite, flexible MOFs MIL-88D has been studied as a nanocontainer for loading lubricant. In this work, the mechanism of oleamine adsorption and desorption by MIL-88D was investigated through molecular simulations and experiments. Molecular simulations showed that the oleamines can be physically adsorbed into open MIL-88Ds with the Fe and O atoms of MIL-88D interacting with oleamine NH2-group. Higher temperature can cause Ole@MIL-88D to release more oleamines, while higher pressure on Ole@MIL-88D caused less oleamines released. Moreover the Ole@MIL-88D was incorporated into epoxy resin (EP) for friction tests. The optimum mass ratio of MIL-88D to EP is 15 wt%, and the EP/Ole@MIL-88D prefers light load and high frequency friction. This work suggests that flexible MOFs can be used as a nanocontainer for loading lubricant, and can be used as a new self-lubricating composite.

Exceptional contribution of iron nanoparticle and aloe vera biomass additives to biogas production from anaerobic digestion of waste sludge

This study aims to investigate, for the first time, the improvement of the anaerobic digestion (AD) performance of waste sludge (WS) by utilizing Aloe vera waste (AVW) and Fe0 nanoparticles. Accordingly, a series of biogas generation experiments were conducted at different mixing ratios (AVW:WS = 0:1, 1:1, 2:1, and 3:1), to find out the optimum ratio for maximizing biogas generation. To gain insights into the improved biogas generation by the addition of AVW, pH value was monitored during the fermentation process and adjusted to different initial values (3, 7, and 12). Moreover, the effect of different concentrations (10 and 50 mg/L) and dosing times (0, 6, 12, 24, 48, and 96 h) of Fe0 nanoparticles on the digestion of the optimized ratio (AVW:WS = 2:1) were investigated. Results showed that the optimum ratio (AVW:WS = 2:1) resulted in improving biogas and methane generation by 62.5 % and 96.0 %, respectively, which is an excellent improvement rate of biogas and methane generation compared with the previously reported values in the literature. The addition of Fe0 at the optimum concentration (10 mg/L) and dosing time (12 h) to the optimized ratio (AVW:WS = 2:1) resulted in enhancing methane generation by 146.9 %.

Effect of Cetyl Trimethyl ammonium bromide (CTAB) amount on the Nanoindentation creep behaviour of Sn-cu-Y2O3 nanocomposite Lead-free solder

Sn-Cu-Y2O3 nanocomposite solder is synthesized from a citrate bath by pulse electrodeposition route. Y2O3 powder is synthesized from a sol-gel assisted combustion route. Different techniques such as SEM, XRD, and TEM are used to characterize Y2O3 powder. The particle size of Y2O3 powder is found to be 27 nm. The effect of adding cetyl trimethyl ammonium bromide (CTAB) on the synthesis of Sn-Cu-Y2O3 nanocomposite lead-free solder is studied. The amount of CTAB is varied for a particular amount of Y2O3 powder. It is carried out to find the exact ratio of CTAB for better dispersion of Y2O3 powder in the electrolytic bath. Because the distribution of reinforcement in the matrix which is associated with the dispersion of Y2O3 powder in the electrolyte is as important as the amount of reinforcement in the solder matrix. For the synthesis of nanocomposite solder, the optimum ratio of CTAB to Y2O3 is found to be 1:1. After the synthesis of nanocomposite solder, the influence of Y2O3 powder on the melting temperature of the solder is also studied. Incorporating Y2O3 has little effect on the melting point of the nanocomposite solder. Nanoindentation creep test results showed that the deposit at 0.2 A/cm2 (monolithic solder) has a lower creep resistance than the nanocomposite solders. Additionally, the creep resistance of the nanocomposite with a CTAB to Y2O3 ratio of 1:1 was higher.

Plateau-Adapted Single-Pump, Single-Bed Vacuum Pressure Swing Adsorption Oxygen Generation Process Simulation and Optimization

To enhance the oxygen guarantee capacity in high altitude areas and address the challenges of traditional pressure swing adsorption oxygen generation fixed equipment with large volume and multiple device modules, a novel single-reversible-pump single-bed vacuum pressure swing adsorption (VPSA) oxygen generation process was proposed and simulated. This study investigated the effects of purge on oxygen productivity, purity, recovery, and energy consumption, determining that the optimum ratio of total oxygen in the purge gas to the total oxygen in the feed gas (P/F) was 0.176. A set of principle prototypes was developed and validated in plains. The process performance was then simulated and studied at altitudes of 3000 m, 4000 m, and 5000 m. Finally, the optimization was carried out by adjusting the product flow rate and feed flow rate, revealing that the best performance can be achieved when the oxygen purity exceeded 90% with lower energy consumption or larger productivity than the optimization goal. This study serves as a valuable reference for the optimization of the VPSA oxygen generation process in a plateau environment.

Engineering Properties and Microstructure of Soils Stabilized by Red-Mud-Based Cementitious Material.

Red mud (RM) is an industrial waste generated in the process of aluminum refinement. The recycling and reusing of RM have become urgent problems to be solved. To explore the feasibility of using RM in geotechnical engineering, this study combined magnesium oxide (MgO) (or calcium oxide (CaO)) with RM as an RM-based binder, which was then used to stabilize the soil. The physical, mechanical, and micro-structural properties of the stabilized soil were investigated. As the content of MgO or CaO in the mixture increased, the unconfined compressive strength (UCS) of the RM-based cementitious materials first increased and then decreased. For the soils stabilized with RM-MgO or RM-CaO, the UCS increased and then decreased, reaching a maximum at RM:MgO = 5:5 or RM:CaO = 8:2. The addition of sodium hydroxide (NaOH) promoted the hydration reaction. The UCS enhancement ranged from 8.09% to 66.67% for the RM-MgO stabilized soils and 204.6% to 346.6% for the RM-CaO stabilized soils. The optimum ratio of the RM-MgO stabilized soil (with NaOH) was 2:8, while that of the RM-CaO stabilized soil (with NaOH) was 4:6. Freeze-thaw cycles reduced the UCS of the stabilized soil, but the resistance of the stabilized soil to freeze-thaw erosion was significantly improved by the addition of RM-MgO or RM-CaO, and the soil stabilized with RM-MgO had better freeze-thaw resistance than that with RM-CaO. The hydrated magnesium silicate generated by the RM-MgO stabilized soil and the hydrated calcium silicate generated by the RM-CaO stabilized soil helped to improve the UCS of the stabilized soil. The freeze-thaw cycles did not weaken the formation of hydration products in the stabilized soil but could result in physical damage to the stabilized soils. The decrease in the UCS of the stabilized soil was mainly due to physical damage.

Fermentation Quality and In Vitro Digestibility of Sweet Corn Processing Byproducts Silage Mixed with Millet Hull or Wheat Bran and Inoculated with a Lactic Acid Bacteria

The aim of the experiment was to investigate the effect of different ratios of excipient (millet hull or wheat bran) and LAB inoculation on the fermentation quality and in vitro digestibility of a mixed silage of SCPBs. The preliminary experimental results showed that inoculating with lactic acid bacteria (LAB) directly in the fresh sweet corn processing byproduct (SCPBs) silage had a higher ammonia nitrogen/total nitrogen (AN/TN) ratio and lower silage fermentation quality due to high moisture content. Subsequently, millet hull or wheat bran were mixed with SCPBs in a 7:3 (T1), 8:2 (T2), and 9:1 (T3) ratio and ensiled with LAB. Under the condition of each mixing ratio, the silage treatments were categorized into groups without any additives (control) and with LAB. Fermentation quality, in vitro digestibility, chemical composition, and energy values were determined after 45 days of silage. The pH, AN/TN, neutral detergent fiber, acid detergent fiber, and acid detergent lignin were lowest in the SCPBs and millet hull mixed silage (SMH) group under the T3 treatment, whereas they were lowest in the SCPBs and wheat bran mixed silage (SWB) group under the T2 treatment. The mean lactic acid and acetic acid values were higher in the SWB group than in the SMH group (6.92, 6.81 vs. 4.00, 4.52). Under the T3 treatment in the SMH group, AN/TN was significantly reduced with the addition of LAB (4.52 vs. 4.37, p < 0.05). The SMH group had the highest crude protein (CP) under the T3 treatment, whereas the SWB group had the highest CP under the T2 treatment. The mean CP in the SWB group was higher than that of the SMH group (18.17, 19.44 vs. 10.55, 10.55). Under the T1 treatment, in the SWB group, the addition of LAB resulted in a significant increase in in vitro crude protein digestibility (p < 0.05). The results showed that silage fermentation quality and in vitro digestibilitv55y improved with the addition of LAB. The optimum mixing ratio for the SWB group was 9:1 and 8:2 for the SMH group.

Mechanical behavior and microstructure evolution of slag-fly ash based geopolymer stabilized sand

Geopolymers made from ground granulated blast-furnace slag and fly ash could effectively address the issues of high energy consumption and emissions associated with Portland cement, which is commonly used as a soil curing agent. In this study, the unconfined compressive strength and microstructure of geopolymer-solidified sand were presented and analyzed. The study focused on effect of the type and ratio of activator, the ratio of slag to fly ash, and the ratio of water to (activator and cementitious materials) (W/(A + C)) on the behavior of geopolymer stabilized sand. The results of computed tomography (CT), and scanning electron microscope (SEM) indicate that the variation in initial water content significantly affects the porosity of the specimen, which increased as initial water content increased. The cracks were mainly found at the joints between the individual aggregates and at the edges of the individual aggregates. The pore size distribution of the specimens was concentrated in the range 0.0761–5 μm, while the polymer particle distribution was concentrated in the range 0.0761–10 μm, with a concentration of over 90 %. A significant amount of cementing material was densely distributed around both the aggregates and the pores. CT and SEM testing techniques enable a thorough analysis and mutual verification of the self-compacting process, pore distribution, and size, as well as the distribution of cementing material within the specimens. The optimum ratio for B-S19 has been determined.

A quality by design approach to optimise disulfide-linked hyaluronic acid hydrogels

In this study, the disulfide-linked hyaluronic acid (HA) hydrogels were optimised for potential application as a scaffold in tissue engineering through the Quality by Design (QbD) approach. For this purpose, HA was first modified by incorporating the cysteine moiety into the HA backbone, which promoted the formation of disulfide cross-linked HA hydrogel at physiological pH. Utilising a Design of Experiments (DoE) methodology, the critical factors to achieve stable biomaterials, i.e. the degree of HA substitution, HA molecular weight, and coupling agent ratio, were explored. To establish a design space, the DoE was performed with 65 kDa, 138 kDa and 200 kDa HA and variable concentrations of coupling agent to optimise conditions to obtain HA hydrogel with improved rheological properties. Thus, HA hydrogel with a 12 % degree of modification, storage modulus of ≈2321 Pa and loss modulus of ≈15 Pa, was achieved with the optimum ratio of coupling agent. Furthermore, biocompatibility assessments in C28/I2 chondrocyte cells demonstrated the non-toxic nature of the hydrogel, underscoring its potential for tissue regeneration. Our findings highlight the efficacy of the QbD approach in designing HA hydrogels with tailored properties for biomedical applications.

Synthesis and drug release kinetics of ciprofloxacin from polyacrylamide/dextran/carbon quantum dots (PAM/Dex/CQD) hydrogels

Sustainable release of drug by utilizing β-cyclodextrin (β-CD) based inclusion complex (IC) is the prime objective of the present work. Herein, polyacrylamide/dextran containing carbon quantum dots (PAM/Dex/CQD) nanocomposite hydrogels are prepared by in situ polymerization of acrylamide. The incorporation of CQD triggers the change in orientation of the PAM/Dex polymeric chains to result the formation of stacked surface morphology of the hydrogel. The average particle size of CQD is found to be 4.13 nm from HRTEM analysis. As-synthesized nanocomposite hydrogel exhibits an optimum swelling ratio of 863 % in aqueous medium. The cytotoxicity study is conducted on HeLa cells by taking up to 2 μM concentration of the prepared nanocomposite hydrogel demonstrate 78 % cell viability. In present study, ciprofloxacin (Cipro) is taken as model drug that achieves release of 64.15 % in 32 h from β-Cipro@PAM/Dex/CQD hydrogels in acidic medium. From theoretical study, release rate constants, R2, Akaike information criterion (AIC) and model selection criterion (MSC) are computed to determine the best fitted kinetics model. Peppas-Sahlin model is the best fitted kinetics model for β-Cipro@PAM/Dex/CQD and concluded that the release of Cipro follows Fickian drug diffusion mechanism in acidic medium.

The novel probiotic preparation based on Lactobacillus spp. mixture on the intestinal bacterial community structure of Cherry Valley duck.

The development and utilization of probiotics have many environmental benefits when they are used to replace antibiotics in animal production. In this study, intestinal lactic acid bacteria were isolated from the intestines of Cherry Valley ducks. Probiotic lactic acid bacterial strains were screened for antibacterial activity and tolerance to produce a Lactobacillus spp. mixture. The effects of the compound on the growth performance and intestinal flora of Cherry Valley ducks were studied. Based on the results of the antibacterial activity and tolerance tests, the highly active strains Lactobacillus casei 1.2435, L. salivarius L621, and L. salivarius L4 from the intestines of Cherry Valley ducks were selected. The optimum ratio of L. casei 1.2435, L. salivarius L621, and L. salivarius L4 was 1:1:2, the amount of inoculum used was 1%, and the fermentation time was 14h. In vivo experiments showed that compared with the control group, the relative abundances of intestinal Lactobacillus and Blautia were significantly increased in the experimental group fed the lactobacilli compound (P < 0.05); the relative abundances of Parabacteroides, [Ruminococcus]_torques_group, and Enterococcus were significantly reduced (P < 0.05), and the growth and development of the dominant intestinal flora were promoted in the Cherry Valley ducks. This study will provide more opportunities for Cherry Valley ducks to choose microecological agents for green and healthy breeding.

Friction properties and prediction of a novel copper-based powder metallurgy material modified with TiB2/B4C composite

By incorporating the dual ceramic elements TiB2/B4C, we investigated their impact on the mechanical properties, thermal properties, and friction performance of copper-based powder metallurgy materials, and elucidated the friction wear mechanism. Additionally, machine learning algorithms were employed to predict the friction coefficient and stability coefficient. The conclusions are as follows:With the increase in the TiB2/B4C ratio, the trend of mechanical properties initially increases and then decreases, with the optimum ratio being 5:3 for TiB2 and B4C, exhibiting superior mechanical properties. Moreover, B4C enhances the thermal conductivity of copper-based friction materials more effectively than TiB2. In terms of overall friction performance, the ratio of TiB2 to B4C at 5:3 yields better frictional properties. The primary components of the friction surface friction film are CuO, Cu2O, Fe2O3, and B2O3, transitioning from a ceramic film to a metallic film as the TiB2/B4C ratio increases. The friction wear mechanism shifts from abrasive wear to severe fatigue wear as the TiB2/B4C ratio increases, accompanied by oxidative wear. Furthermore, an AdaBoost algorithm model was developed to effectively predict the friction coefficient and stability coefficient, with accuracies of 0.9993 and 0.8739, respectively.

Effect of polyvinylpyrrolidone and lithium chloride composite desiccant-coated heat exchangers on dehumidification studies

Cooling systems are necessities that remain energy intensive, particularly in tropical regions with elevated humidities and temperatures. Conventional vapor-compression air-conditioners are often inefficient because the sensible and latent heat loads are intrinsically coupled. To realize more energy-efficient cooling, solid desiccant-coated devices can be introduced to mitigate the latent heat load. Among such devices, desiccant-coated heat exchangers (DCHEs) are attractive for enabling nearly isothermal dehumidification. Hence, desiccants with high sorption capacity and rapid kinetics are essential. Solid polymeric desiccants are well-positioned to meet these requirements but comprehensive studies on the dehumidification performance of solid polymeric desiccant-coated heat exchangers are currently lacking. In this study, we investigated the potential of polyvinylpyrrolidone (PVP) and lithium chloride (LiCl) composites as desiccant materials at both material and system levels in terms of gravimetric water uptake. Specifically, LiCl is a hygroscopic salt bound by the moisture-sorbing PVP matrix. This work also demonstrates how the Elovich model accurately predicted the PVP-LiCl composite’s sorption kinetics. The results show that the optimum PVP-LiCl composite ratio is 66.7 wt%, with an equilibrium sorption capacity of 280 % at 75 % RH and 25 °C, compared to 29 % for silica gel under the same condition. With much superior sorption kinetics and capacity, the PVP-LiCl-coated prototype heat exchanger demonstrated a moisture removal capacity eight times higher than a silica gel-coated one under dynamic flow towards energy savings in air-conditioning systems.

Performance of Lightweight Peach-Shell Concrete with Optimal Substitution Ratio

Performance of Lightweight Peach-Shell Concrete with Optimal Substitution Ratio

Optimal screening method for dosage of calcium-based nanosilica modified expansive soils improver based on cost-effectiveness

Under complex natural environments, the properties of lime-modified expansive soil may deteriorate. This facilitates the need for newer materials to develop composite modifiers to improve the anti-deterioration performance. Nanosilica (NS), which is a highly reactive material, is a good promoter of reaction systems with volcanic ash. In this paper, lime is mixed with NS according to a specified ratio to form calcium-based nanosilica (NS-C). NS-C significantly increased the unconfined compressive strength, cohesion, and internal friction angle and decreased the plasticity index, free swelling ratio, and permeability coefficient. The optimum ratio of nano-silica to lime in compound modifier was determined to be 1:8. NS can facilitate the production of a large amount of hydration products in the early stage of the reaction of stabilized soil, thus strengthening the connection between soil particles. In addition, NS exhibits good filling effect on the tiny pores between soil particles. The properties of NS-C stabilized soils with different ratios and curing times were determined to evaluate the modification effect and mechanism of composite modifier and obtain the optimal dosage for Hefei expansive soils in road-base edging technology. The optimum content of the compound modifier for expansive soils in the Hefei area should be 6 %, and the curing time should be at least 14 days.