Table of Content

15 December 2021, Volume 40 Issue 12

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Cement and Concrete

Research Progress of Concrete Prepared by Desert Sand

SHEN Yanjun, HAO Jianshuai, BAI Zhipeng, ZHOU Zihan, LI Yugen, LIAO Taichang, ZHANG Kaifeng

2021, 40(12):  3879-3890. 

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Adopting the strategy of “taking local materials according to local conditions” and reasonably using desert sand for concrete preparation is an effective way to alleviate the contradiction between supply and demand of sand for construction in Northwest China. Firstly, the basic physicochemical characteristics of desert sand in different regions through the method of combining literature research and statistical analysis were summarized. Secondly, the current research status of desert sand concrete preparation was combed. And its existing problems, prospected the future research development direction of desert sand concrete were summarized. Studies at the present stage show that desert sand can replace or partially replace aggregate in the preparation of concrete under certain conditions. The workability, mechanical properties and durability (frost resistance, high temperature resistance) of concrete prepared by desert sand partially replacing river sand meet the general engineering requirements, and some conditions are even better than ordinary concrete. This research review provides reference for the application of desert sand concrete in practical engineering, and provides a new model reference for realizing the green mining and resource utilization of desert sand.

Review of Expansion Prediction Models for Alkali-Silica Reaction of Concrete

GONG Qingnan, WANG Dehui

2021, 40(12):  3891-3902. 

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This paper reviews the research status of the expansion prediction model of alkali-silica reaction (ASR). The damage caused by ASR to concrete structure is difficult to repair and the repair cost is high. To deal with this kind of durability problem, prevention is the main, and remedial is the secondary. Accurate prediction model can evaluate the real-time state of concrete structure and help to inhibit the ASR in concrete. This paper first summarizes the process and mechanism of ASR in concrete, and then introduces the research status of expansion prediction model of ASR in detail. Multiple factors such as reactant content, temperature, humidity, cementitious material composition and aggregate size should be considered in the process of ASR modeling. The model of ASR mainly includes theoretical model, structural model (macro model) and material model (meso model). The theoretical model is mainly used to describe the chemical mechanism of ASR and predict the worst particle size of aggregate, but the model is only applicable to specific types of aggregate; the material model explains the deterioration mechanism of concrete affected by ASR at the material level, but ignores the effects of concrete shrinkage and creep; the structural model is usually used to simulate and predict the mechanical behavior of concrete structures under ASR, but the chemical process of alkali-silica expansion and the effect of ion diffusion on ASR expansion are not fully considered.

Effect of Ca/Si Ratio on Structure and Mechanical Properties of Calcium Silicate Hydrate via Molecular Dynamics Simulations

XU Xiaofei, TANG Shengwen, HE Zhen

2021, 40(12):  3903-3909. 

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Calcium silicate hydrate (C-S-H), as the main binding phase of Portland cement-based materials, significantly effects the durability, physical and mechanical properties of cement-based materials. In this paper, 5 models with different Ca/Si ratios from 1.1 to 1.9 were constructed, and molecular dynamics was carried out to simulate the nanoindentation test on C-S-H models along x, y and z directions. Then their indention modulus and hardness were calculated by the typical Oliver-Pharr method respectively. According to results from present simulation, as the Ca/Si ratio increases, the density and the average silicate chain length gradually decrease, but the W/Si ratio gradually increases. The mechanical properties are greatly influenced by the Ca/Si ratio, as the Ca/Si ratio increases, the degree of the defect of silicate chains increases, and the stability of calcium silicate sheets is correspondingly reduced, resulting in the weakening of the ability of C-S-H structure to resist deformation and the reduction of indention modulus and hardness. Indention modulus and hardness values in the direction parallel to calcium silicate layers are closed, while the values in the direction perpendicular to calcium silicate layers are slight lower, C-S-H is similar to transversely isotropic structure. As Ca/Si ratio increases, values of both three directions are gradually closed, C-S-H changes from transversely isotropic structure to isotropic structure.

Optimization Study on Mineral Composition of Ternesite-Ye’elimite Cement Clinker

SHEN Yan, WANG Peifang, ZHU Hangyu

2021, 40(12):  3910-3917. 

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Ternesite-ye’elimite cement is a new type of low-carbon cement. The hydration reactivity of ternesite has a positive effect on the performance of cement. In this work, ternesite-ye’elimite cement was produced by adding dopants. The optimization of ternesite, ye’elimite and gypsum contents was studied. The results indicate that the phase composition of clinkers is consistent with the designed value. The increase of ye’elimite content improves the early strength of cement pastes, and the appropriate content of ye’elimite is 30% to 40% (mass fraction). With the increase of ternesite content, the compressive strength increases. However, when the theoretical content of ternesite reaches 48% (mass fraction), the compressive strength of cement pastes decreases. The appropriate content of ternesite is 40% to 55% (mass fraction), and the optimized content of ternesite varies according to the content of ye’elimite. The addition of gypsum is beneficial for the strength development of cement pastes. Compared with natural gypsum, anhydrite can better promote the strength development. Therefore, anhydrite is preferentially selected as the added gypsum. The optimized content of anhydrite is 8% (mass fraction), and the cement obtains the compressive strength of 76 MPa at 28 d. The increased content of anhydrite promotes the formation of ettringite, but excessive anhydrite hinders the hydration of ternesite.

Preparation of Nano-Particles Reinforced Cement Paste Based on Response Surface Method

WANG Zhihang, BAI Erlei, XU Jinyu, LUO Xin, MENG Xin, LIU Gaojie, REN Biao, ZHU Jingsai

2021, 40(12):  3918-3926. 

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Based on the response surface method, considering the three key influencing factors of nano-particles content (NPC), polycarboxylates superplasticizer content (PSC), and water-binder ratio (WBR), the response was based on the compressive strength of hardened cement paste. Using the central composite design method to design experiments, the strength models of nano-SiO₂, nano-CaCO₃, and nano-Al₂O₃ reinforced cement paste were established. The nano-CaCO₃ reinforced cement paste strength model was taked as an example to analyze the influences of various factors on the strength and verify the strength model. The results show that when the mass ratio of nano-particle to cement is 0.027 0, the mass ratio of polycarboxylates superplasticizer to cement is 0.017 5, and water-binder ratio is 0.25, the three nano-particles reinforced cement pastes have higher strength. The strength models of nano-SiO₂, nano-CaCO₃, nano-Al₂O₃ reinforced cement paste have high accuracy and reliability. The compressive strength response value of nano-CaCO₃ reinforced cement paste first increases and then decreases with the increase of NPC and PSC, and gradually decreases with the increase of WBR.

Research on Bonding Properties of Fiber and Cement Mortar Interface

ZHANG Xianmin, CHEN Xuefang, LI Changhui, HUO Haifeng, CHEN Yu

2021, 40(12):  3927-3937. 

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In this paper, a single coarse fiber pull-out test was carried out on a “figure-eight” specimen. Types of fibers, diameters of fibers, embedding lengths of fibers and water-binder ratio of mortar matrix were considered in the mixed orthogonal experiments to study the significant priority of the bond strength as well as the best combination between fiber and mortar matrix. Besides, the maximum fiber pull-out load and load-slip curves were obtained. The interface bonding performance of fiber and cement mortar matrix was systematically analyzed. The test results show that the interface bond strength of the polypropylene coarse fiber with a diameter of 0.6 mm and an embedded length of 20 mm to a mortar matrix with a water-binder ratio of 0.51 is the largest. The average bond strength of that is 7.71 MPa and the equivalent bond strength is up to 13.25 MPa. The interface bond strength of mortar matrix with polyvinyl alcohol (PVA) fiber with a diameter of 0.6 mm, an embedded length of 10 mm and a water-binder ratio of 0.41 is second. The priority of the influence of the four factors on the bond strength of the interface is fiber type, fiber diameter, water-binder ratio of mortar matrix and embedded length of fibers. The fiber type has a significant effect on the average bond strength of the interface, and the fiber diameter has a significant effect on the equivalent bond strength of the interface.

Preparation of Portland Cement Based Composite Electrolyte and Its Application in Building Energy Storage Devices

YUAN Xuefeng, WANG Hua

2021, 40(12):  3938-3944. 

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In recent years, it is interesting that cement based composites can be used for building energy storage. In this paper, a kind of optimized cement based composite electrolyte was prepared by mixing Portland cement and acrylamide (AM). The effects of AM mass fraction of 0%, 25.0%, 27.5%, 30.0%, 32.5% and 35.0% on the ionic conductivity, mechanical properties and microstructure of the structural electrolyte were investigated. The multifunctional analysis shows that the increase of AM content is helpful to improve the ionic conductivity of Portland cement based composite electrolyte, but it inevitably reduces the compressive strength of electrolyte. When AM content is 30.0%, the ionic conductivity and compressive strength the Portland cement based composite electrolyte reach an ideal balance. At this time, the compressive strength is as high as 41.1 MPa, and the ionic conductivity is up to 22.47 mS·cm^-1. In addition, integrated structural supercapacitors were assembled with these structural electrolytes sandwiched by rGO electrodes, and a series of electrochemical performance tests were carried out. It is found that the maximum area specific capacitance of the structure supercapacitor based on Portland cement based composite electrolyte with AM content of 30.0% can reach 96.8 mF·cm^-2. In addition, its area capacitance retention rate keeps 91.08% after 5 000 charge-discharge cycles at a current density of 0.1 mA·cm^-2, indicating that the structural supercapacitor has a broad prospect in the field of building energy storage application.

Experimental Study on Interfacial Antifreeze Performance of UHPC and Normal Concrete

XIE Jian, CHEN Yujie, SUN Yadan

2021, 40(12):  3945-3955. 

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Ultra high performance concrete (UHPC) is considered to be the most promising material for structural repair due to its high strength and excellent durability. At the same time, the interfacial bonding performance between UHPC and normal concrete (NC) is the key to the reliability of applying UHPC in concrete reinforcement and repair engineering. To achieve the interfacial behavior of UHPC-NC under serve cold environment, freeze-thaw cycle tests were carried out on UHPC-NC bonding specimens at －60 ℃. The macroscopic morphological changes and mass change rates of the specimens after the freeze-thaw cycles were obtained. Meanwhile, based on the tensile bonding test, the bonding strength and failure mode were analyzed. Moreover, the interface damage mechanism of UHPC-NC specimen under freeze-thaw action was also preliminarily explored. The influence of －60 ℃ freeze-thaw cycles on the interface bonding performance of UHPC-NC specimens, and the influence of different treatment methods of the interface (brush, water jet and splitting) against the －60 ℃ freeze-thaw cycles were presented. The test results show that the －60 ℃ freeze-thaw environment has a great influence on the bonding strength of UHPC-NC specimens. The interface bonding strength decreases rapidly first and then slowly. After 10 freeze-thaw cycles, 15 freeze-thaw cycles and 20 freeze-thaw cycles, the interface bond strength of the splitting group decrease to 72.94%, 55.62% and 44.33% of the benchmark interface bond strength, respectively. The higher the interface roughness, the greater the residual bond strength of the interface. After 20 freeze-thaw cycles, the bond strength of the splitting group is 2.03 times than that of the water jet sample.

Mechanical Properties and Microstructure of Ultra-High Performance Concrete Containing Glass Powder

YANG Zhenying, ZHOU Changshun

2021, 40(12):  3956-3962. 

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Glass powder (GP) is an environmental-friendly solid waste material. A kind of green ultra-high performance concrete (UHPC) was prepared using GP in order to save resources and solve the environmental pollution problem effectively. The effect of GP as a variety of supplementary cementitious materials on the mechanical properties and microstructure of UHPC was studied. Results show that GP improves the flowability of UHPC. The incorporation of GP reduces the early age mechanical properties of UHPC, while enhances the mechanical properties of UHPC at later age. The compressive strength of UHPC sample with 20% (mass fraction) GP at 28 d is close to that of the reference group, while the compressive strength at 90 d is 13.2% higher than that of the reference group. UHPC sample (90 d) with an addition of 20% GP owns the lowest total porosity, which is 14.6% lower than that of the reference group. At the same time, the content of high-density hydrated calcium silicate gel increases by 20%, resulting in denser microstructure of UHPC. GP has a good combination of the micro-aggregate filling effect and the pozzolanic effect.

Influence of Early Age Disturbance on Mechanical Properties of Concrete Based on Acoustic Emission Technology

ZHANG Changjiang, XU Baishun, ZHAO Zhimeng, NI Tianmeng, LIU Bin

2021, 40(12):  3964-3975. 

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In order to study the influence of early age disturbance on the mechanical properties of concrete and clarify its influence mechanism,the strength test and acoustic emission test were carried out in the initial and middle stages of condensation by means of indoor disturbance. The influence of early age disturbance on the mechanical properties of concrete was analyzed from the mesoscopic view. The results show that the early age disturbance has a great influence on the mechanical properties of concrete. The compressive strength of disturbed concrete increases in the initial stage of condensation, and decreases in the middle stage of condensation. Meanwhile, the influences of different disturbance parameters on the compressive strength of specimens are different. According to the analysis of different acoustic emission parameters, it is found that the smaller the number of initial microcracks is, the smaller the damage is and the greater the cumulative energy is when the specimen is destroyed, and the smaller the proportion of shear crack events is. The damage mechanism of early age disturbance on mechanical properties of concrete is explained from the perspective of initial microcracks.

Mechanical Properties and Damage Mechanism of Basalt Textile Reinforced Concrete after High Temperature

HOU Zhenguo, HE Haiying, XU Ping, SUN Weidong, DAI Junfeng, HU Guangqin

2021, 40(12):  3976-3984. 

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Basalt textile reinforced concrete (TRC) was prepared with Portland and high aluminate cement respectively. The damage mechanism of TRC after high temperature was investigated by four-point bending test, XRD diffraction and SEM. The results show that basalt fiber textile can effectively reduce the deformation of TRC sheets and inhibit the expansion of cracks at high temperature. The deformation and mass loss of high aluminate cement-based TRC are smaller than those of Portland cement-based TRC after high temperature. The flexural bearing capacity of basalt TRC decreases approximately linearly with the increase of temperature, and the decrease is mainly due to the combined effect of three factors: the damage of concrete matrix at high temperature, the high temperature deterioration of fiber woven fabric, the deterioration of bond between fiber and TRC matrix. SEM analysis shows that high aluminate cement-based TRC is denser and more resistant to high temperature than Portland cement-based TRC. This study provides a reference for the design and application of TRC in high temperature environment.

Hydration Heat Prediction of Calcium Silicate Slag Cement Composite Cementitious Material Based on ARIMA Model

YAN Changwang, SHEN Xiaowei, ZHANG Ju, WANG Xiaoxiao, YU Hongyuan

2021, 40(12):  3985-3992. 

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Predicting the heat generated in the hydration process of calcium silicate slag cement composite cementitious material has practical significance for its application in concrete structures. In this paper, based on the basic theory of ARIMA model, the hydration heat prediction models of composite cementitious materials with 0%, 10% and 30% (mass fraction, the same below) calcium silicate slag were established. The accuracy and reliability of the model were verified by comparing with the text values. Based on the text values of composite cementitious materials with 0%, 10%, and 30% calcium silicate slag, the prediction models of hydration heat at different ages were established, and the prediction of hydration heat of composite cementitious materials with other calcium silicate slag content was carried out. The results show that the average relative errors between predicted values and test values are all less than 5% under the calcium silicate slag content of 0%, 10% and 30%, which indicates that the ARIMA model has high accuracy and reliability in predicting the hydration heat of composite cementitious materials. The prediction results of hydration heat of composite cementitious materials with other calcium silicate slag content are in line with the actual change trend, which further proves the feasibility of ARIMA model in the prediction of hydration heat. This provides an effective method for quantitative research and prediction of hydration heat of composite cementitious materials.

Pore Structure Characteristics and Chloride Ion Corrosion Resistance Mechanism of Coal Gangue Concrete under Drying-Wetting Cycles

QIU Jisheng, ZHANG Ruyi, HOU Bowen, GUAN Xiao, GAO Xujun, LI Leilei

2021, 40(12):  3993-4001. 

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Chloride ion corrosion is an important factor affecting the durability of concrete.The chloride ion corrosion resistance of coal gangue concrete by drying-wetting cycles test was studied, and the effect of coal gangue volume substitution rate (0%, 20%, 40%, 60%) on the chloride ion concentration distribution and apparent diffusion coefficient was analyzed. The pore structure parameters of coal gangue concrete were determined by mercury intrusion porosimetry, and the fractal dimension of pore volume was calculated. The influence of pore structure on chloride ion corrosion resistance of coal gangue concrete was studied. The results show that with the increase of the content of coal gangue, the free chloride ion concentration decreases first and then increases, while the apparent diffusion coefficient increases first and then decreases. Compared with the concrete without coal gangue, when the content of coal gangue is 40%, the compactness of concrete is the best and the fractal dimension of pore volume is the largest. At this moment the chloride ion concentration is the lowest and the chloride ion corrosion resistance of coal gangue concrete is the best. The apparent diffusion coefficient of chloride ion decreases by 35.68%.

Solid Waste and Eco-Materials

Deformation and Breakage Characteristics of Granular Gangue in Confined Compression Process

XIAO Bo, LI Yongliang, LI Jin, WANG Yuxuan, WANG Zixu

2021, 40(12):  4002-4010. 

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The main sources of macroscopic deformation of granular gangue are the direct compression of the initial pores of the sample during the confined loading process and the refilling of pores after the crushing of coarse gangue in the compaction stage. An experimental system combining loading installation with acoustic emission device was adopted, and the loading rate was taken as influencing factor. Based on theoretical derivation and experimental data analysis, the macroscopic deformation, porosity and breakage degree of granular gangue in the confined compression process were systematically studied. The results show that the direct compression of initial pores has the most obvious effect on the macroscopic deformation. The porosity increases with the decrease of strain and decreases with the decrease of stress in an inversely proportional composite function. The breakage fractal function of granular gangue is rededuced. By comparing the slope of logarithmic curve, it is found that the higher the loading rate is, the smaller the breakage degree is. The acoustic emission location number increases with the increase of test force, but decreases with the increase of loading rate. The particle fragmentation in the middle of the sample is the most intensive. The larger the degree of particle breakage is, the higher the secondary filling rate of pores is. The pores are not easy to be further compressed, and the anti-deformation ability of the sample is enhanced.

Ion Concentration Distribution and Vickers Hardness Degradation of Fly Ash Cement Pastes in Complicated Environment

WANG Tao, CHU Hongqiang, DING Tianyun, ZHU Zhengyu, ZENG Youxu, XIE Jiaxuan, JIANG Linhua

2021, 40(12):  4011-4019. 

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Reinforced concrete structures in subway engineering are often exposed to a combination of sulfate, chloride and stray current. In this study, the effect of the amount of fly ash on the distribution of sulfate ion concentration distribution, chloride ion concentration distribution and Vickers hardness of cement pastes under the coupling effect of sulfate, chloride and electric field were discussed. Moreover, the logistic function was applied to the prediction model of Vickers hardness. Finally, mechanism and deterioration of cement pastes were analyzed by XRD. The results show that as the erosion depth increases, the concentration of sulfate ion decreases continuously, while chloride ion concentration increases first and then declines gradually. With the increase of fly ash addition, the chloride ion and sulfate ion invading cement pastes decrease first and then increase. When the fly ash content increases to 10% (mass fraction), the content of chloride ion and sulfate ion invading specimen is the lowest. The Vickers hardness distribution of the eroded cement pastes is divided into three areas: degraded area, enhanced area and intact area. There is a good correlation between the prediction model and the experimental values of Vickers hardness. A suitable content of fly ash addition reduces the formation of ettringite and gypsum in the eroded cement pastes, and improves the stability of bound chloride ion.

Preparation and Properties of Fly Ash-Based Geopolymer Inorganic Coatings

FAN Ying, LI Yuan, LIU Changming, YANG Bin, LIU Xueting

2021, 40(12):  4020-4029. 

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The fly ash-based geopolymer inorganic coatings were prepared with low-calcium fly ash as the main raw material, sodium silicate and sodium hydroxide as the composite alkaline activator, silane coupling agent (KH550) as the reinforcing material, and silicone acrylic emulsion as the auxiliary film-forming material. The effects of silane coupling agent content, reaction temperature and water-solid ratio on the film-forming property, water resistance and scrub resistance of geopolymer inorganic coatings were studied, and the microstructure and high temperature resistance of inorganic coatings were characterized by XRD, FTIR, SEM, TG-DSC. The results show that, when the preparation temperature, the water-solid ratio and the content of silane coupling agent are 60 ℃, 0.31 (mass ratio) and 3.6% (mass fraction), respectively. The obtained geopolymer inorganic coating has good film-forming performance at room temperature without cracking, the mass water absorption rate of the coating is 1.84% in 24 h, the scrub resistance reaches 12 000 times, and the hardness of 7 d is 154 s. The geopolymer inorganic coating is mainly composed of amorphous aluminosilicate gel. The cluster featured products formed by hydrolysis and bonding of silane coupling agent fill the pores of geopolymer coating, which increase the compactness of the coating and inhibit the generation of cracks. The mass loss rate of the coating is 12.0% to 13.0% when TG-DSC is measured between 25 ℃ and 800 ℃, and no obvious thermal decomposition is found, which indicates that the coating has good high temperature resistance.

Solid Waste and Eco-Materials

Effect of Silica Fume on Properties of Ultra-Light Cement-Based Composite Thermal Insulation Materials

WU Zihao, WANG Wuxiang, LIU Xiaotong, WANG Aijun, ZHANG Leilei, YANG Jun

2021, 40(12):  4030-4036. 

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In this paper, using the cement as the cementing material, expanded polystyrene foam (EPS) particles, admixture, foams and modifiers, water and others as the main raw materials, using physical foaming process to prepare the ultra-light cement-based composite thermal insulation materials (UCIM). UCIM was composed of EPS particles and foamed concrete matrix through interpenetrating, after different kinds of admixtures were equivalent to replace cement, the inclusion of cement paste on EPS particles was affected to different degrees, so that the uniformity of UCIM structure and product properties were affected. Through the design of different amounts of admixtures, the uniformity and strength of UCIM prepared by silica fume, metakaolin and mineral powder were compared. The results show that there is no delamination and segregation phenomenon, and the strength test results of UCIM are good when silica fume is used. And by photographing micropore, testing strength and thermal performance, the effect of the silica fume content on the pore structure, strength and thermal conductivity of foamed concrete matrix in UCIM was studied systematically. The results show that the appropriate amount of silica fume improves the mechanical properties of UCIM, and reduces the average pore size of foamed concrete matrix in UCIM, which is beneficial to reduce the thermal conductivity of UCIM.

Performance and Mechanism of Solid Alkali-Activated Slag/Fly Ash Grouting Material

CAO Weiwei, LEI Tao, MIN Zhaohui, XU Xiaolong, DUAN Pengpeng

2021, 40(12):  4037-4043. 

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The solid alkali-activated geopolymer grouting material was prepared by slag/fly ash as the raw material and NaOH/Na₂SiO₃·5H₂O as the activator. The effect of activator and curing conditions on mechanical properties, setting time and fluidity were investigated. It is found that when the solid alkali-activator is added with the dosage of 8% (mass fraction) and modulus of 1.0, the initial setting time and working time of grouting material can reach 120 min and 50 min, respectively. After 28 d of curing, the flexural and compressive strength of hydration product reach 7.1 MPa and 42.7 MPa, respectively. It also shows that compared with un-sealed curing, sealed curing is conducive to the formation of early strength of materials, the compressive strength of 1 d, 3 d and 7 d increases by 38.0%, 38.2% and 19.3%, respectively. The microstructure of product was analyzed by methods of XRD, FT-IR, SEM/EDS. The results show that the raw material is completely hydrated, and the product formed by grouting material mainly includes amorphous hydration products, calcium zeolite, hydrated aluminum silicate sodium calcium ore and C-S-H gel. During the reaction process, Si—O—Al and Si—O—Si derived from raw materials recombine to form gel, and agglomerated into spherical products of calcium zeolite to improve the strength of the material.

Properties and Microstructure of Steel Slag Powder-Fly Ash Based Geopolymer

ZHANG Xiling, GUO Haifeng, TANG Ziqi, HE Zhiwei, SONG Liting, YU Mengqin

2021, 40(12):  4044-4051. 

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Steel slag powder and fly ash were used as the main raw materials to prepare geopolymers. The compressive strength was used as the index to optimize the preparation conditions. The factors affecting strength of the geopolymers were discussed. The phase composition, microstructure and thermostability of the products were characterized by SEM, XRD and TG-DSC. The results show that the compressive strength of geopolymer increases first and then decreases with the increase of the content of steel slag powder and activator, and increases with the increase of curing temperature, among which curing temperature is the most significant factor, and modulus of sodium silicate is the weakest. The optimum process conditions are as follows: sodium silicate modulus 1.0, sodium silicate content 20% (mass fraction), steel slag powder content 20% (mass fraction), liquid-solid ratio 0.3, curing temperature 60 ℃. The 3 d and 7 d compressive strength of geopolymers are as high as 40.11 MPa and 43.03 MPa. Solidified Pb²⁺ has little effect on its strength and the solidified effect is more than 99.99%. Geopolymer has high surface density, excellent thermal stability, and no obvious crack and obvious steel slag particle profile is not observed. Its crystal phase is mainly quartz and mullite.

Solid Waste and Eco-Materials

Analysis of Hydration Properties of HBSS-PG-AC Composite Cementitious Materials Excited by Sodium Silicate

QING Sancheng, MA Liping, YANG Jing, AO Ran, YIN Xia, MU Liusen

2021, 40(12):  4052-4060. 

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Composite cementitious materials were prepared by using phosphogypsum (PG), hot-braised steel slag (HBSS), Portland cement and aluminate cement (CA) as main raw materials, and sodium silicate as alkali activator. In the curing age from 0 d to 28 d, the compressive strength and expansion rate of materials were tested in the experiments. Meanwhile, the synergic mechanisms of hydration synergism among phosphogypsum, hot-braised steel slag and aluminate cement were analyzed by X-ray diffractometer (XRD), scanning electron microscope (SEM) and specific surface area and porosity (BET) measurement. The results show that the steel slag powder through 0.300 mm sieve-aperture has both good skeleton filling and gelling properties. In the hydration process, sodium silicate increases the dissolving rate of vitreous network structure on the surface of steel slag and promotes the formation of C-A-S-H from steel slag and aluminate cement. Furthermore, the phase-transforming shrinkage of C-A-H is inhibited by the ettringite formed with the reaction of aluminate cement and phosphogypsum. In addition, a wealth of ettringite and C-A-H is rapidly generated and covered on the surface of steel slag with excessive addition of aluminate cement, which hinders the dissolution promoting effect of Na₂SiO₃ on the glass network structure of steel slag. This paper provides theoretical basis for the collaborative utilization of phosphogypsum and steel slag.

Particle Characteristics of Recycled Fine Aggregate and Properties of Prepared Mortar Based on Particle Shape Analysis

SHI Yanke, ZHANG Luobing, WANG Yuhang, LIU Weiwei, HOU Rongbin, MA Juntao

2021, 40(12):  4061-4069. 

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Based on the analysis of the particle morphology parameters of recycled fine aggregate by the digital image technology, the particle characteristics such as bulk density, water absorption and crushing value of recycled fine aggregate were studied, and the workability and mechanical properties of cement prepared with the recycled fine aggregates were analyzed. The results show that compared with the standard sand and natural river sand at the same grade, the parameters such as dullness, aspect ratio, solidity and roundness of recycled fine aggregate are decreased, and the crushing value and water absorption are significantly increased. The fluidity of the prepared cement mortar with recycled fine aggregate decreases significantly when the mass substitution amount of recycled fine aggregate reaches 30%, and the compressive strength and peak stress decrease significantly when the mass substitution amount of recycled fine aggregate reaches 40%.

Mechanism and Reliability Analysis of Sulfate Resistance of Recycled Concrete

DU Kangwu, WEI Wei, CAI Chenhui, SUN Xin, QIAO Hongxia

2021, 40(12):  4070-4076. 

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Recycled aggregate concrete (RAC) was prepared by different mass admixture of recycled coarse aggregate (0%, 30% and 50%) and recycled fine aggregate (0% and 15%). The deterioration law of RAC mass and relative dynamic elastic modulus in sulfate dry-wet cycle test was studied. The sulfate resistance of RAC under different admixture was evaluated. The results show that with the increase of dry-wet cycles of sulfate, the relative dynamic elastic modulus increases first and then decreases, and the mass loss rate decreases first and then increases. The maximum relative dynamic elastic modulus loss of recycled coarse aggregate concrete reaches 60%, and the maximum mass increase is 0.43%, after 80 times of dry-wet cycles. In addition, the reliability model was established by Winner distribution. The evolution of RAC was evaluated under sulfate dry-wet cycle, and the morphology of RAC after erosion was analyzed by scanning electron microscopy (SEM).

Ceramics

Foamed Ceramics Prepared by Titanium-Bearing Blast Furnace Slag with Borax as Flux Agent

LI Jiahao, LIANG Zongyu, YANG He, MA Minglong

2021, 40(12):  4077-4083. 

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Foamed ceramics were prepared with purple shale and titanium-bearing blast furnace slag (BFS)as raw materials, and borax as flux agent, silicon carbide (SiC) as foaming agent. By analyzing the porosity, closed porosity, pore size distribution, apparent density, compressive strength and thermal conductivity, the effects of the composition of raw materials and borax addition on pore structure and physical properties were studied. The result indicates that as the BFS proportion increases, the pore size distribution of samples increases while the pore uniformity decreases. With the increase of borax addition, the compressive strength increases and the thermal conductivity decreases. The optimized proportion (mass fraction) of raw materials is 70% shale and 30% BFS, with 4% borax and 0.2% SiC addition. The foamed ceramics exhibites apparent density of 0.374 g·cm^-3, thermal conductivity of 0.121 W·m^-1·K^-1, compressive strength of 2.59 MPa, which meets the requirements of building exterior insulation foamed ceramics. The main crystal phases of foamed ceramics are anorthite, quartz, diopside and pseudobrookite.

Properties and Characterization of SiC Woodceramics Fabricated from Boxwood

CAO Yu, ZHANG Liqiang, CHEN Zhaoke, HUANG Hangtao

2021, 40(12):  4084-4091. 

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SiC woodceramics is a new type of ceramic material with broad application prospects in recent years. Using green and renewable wood as the original material, the ceramics fabricated by the reaction sintering process has excellent high-temperature mechanical properties. In order to explore the factors that affect the properties of biomass ceramic materials, boxwood was pyrolyzed under the protection of nitrogen at 800 ℃ to form a biomass carbon template, and then SiC woodceramics were fabricated by liquid silicon infiltration at 1 650 ℃ and 1 900 ℃. In order to determine the prepared materials and their properties, the phase composition and microstructure were studied with X-ray diffraction (XRD) and scanning electron microscopy (SEM), the porosity and density were measured by Archimedes drainage method, the bending strength of ceramics was measured by three-point bending method, and the microhardness was determined by Vickers hardness tester. The results show that SiC woodceramics with uniform microstructure are fabricated by liquid silicon infiltration at 1 650 ℃. The mechanical properties and density (2.27 g/cm³) of ceramics fabricated by liquid silicon infiltration at 1 650 ℃ are better than those fabricated at 1 900 ℃, and the bending strength is 192.45 MPa. The free Si increases the density of SiC woodceramics as well as enhances the bending strength and microhardness.

Preparation and Coloring Performance Analysis of Fe-Cr-Ni-Mn System Black Ceramic Pigment

LI Zhiqiao, ZHANG Xiang, MA Guojun, LIU Mengke, WANG Qiang

2021, 40(12):  4092-4101. 

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Fe₂O₃, Cr₂O₃, MnO and NiO were used as raw materials to prepare Fe-Cr-Ni-Mn black ceramic pigments by solid-phase synthesis method. The prepared pigments were analyzed by using X-ray diffractometer (XRD), colorimeter, scanning electron microscope (SEM), ultraviolet-visible (UV-Vis) spectrophotometer and other analytical methods to study the effects of raw material ratio, sintering temperature, holding time and cooling method on the coloring performance of pigments. The results show that when the molar ratio of Fe₂O₃, Cr₂O₃, MnO and NiO is 6:1:1:1, the sintering temperature is 1 150 ℃, the holding time is 45 min, and the cooling method is furnace cooling, the particle size of the prepared pigment is fine and uniform distribution, and the L^*, a^* and b^* values are 18.02, 0.20 and 0, respectively. The forbidden band width of the prepared pigment is 1.25 eV, and the color is pure black. In addition, the phases of pigment are mainly composed of NiFe₂O₄, NiCr₂O₄ and Ni[Mn_0.5Cr_1.5]O₄. When the prepared pigment is applied to the black ceramic glaze, the glaze surface is pure black, smooth and compact, indicating that the pigment has excellent coloring properties and application potential.

Glass

Effect of CaO/MgO Mass Ratio on Phases and Properties of Glass-Ceramics Prepared from Granite Tailings

LUO Yunlong, WANG Fu, ZHU Hanzhen, LIAO Qilong, XU Guoliang, LIU Laibao, ZHANG Lihua

2021, 40(12):  4102-4108. 

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The R₂O-CaO-MgO-Al₂O₃-SiO₂ building glass-ceramics have been synthesized by the method of monolithic crystallization. The granite tailings (mass fraction: 56%), TiO₂, and Na₂SiF₆ were used as the main raw material, main nucleating agent, and flux and nucleating agent, respectively. The effect of CaO/MgO mass ratio on the crystallization capacity, crystal phase composition, microstructure and properties of glass-ceramics were investigated. The results show that the increase of CaO/MgO mass ratio is beneficial to the crystallization of parent glasses. When the CaO/MgO mass ratio is lower than 0.88, the main crystalline phases of glass-ceramics are anorthite and hornblende, otherwise, the main crystallize phase transforms into anorthite. Based on the results of XRD, the diffraction peak of anorthite become stronger with CaO/MgO mass ratio increasing. Besides, with the increase of CaO/MgO mass ratio, the number of crystals and grain size gradually increased, the volume density and microhardness increase first and then decrease. When the mass ratio of CaO/MgO is 0.57, the volume density has a maximum value of 2.752 5 g/cm³. Furthermore, the microhardness reaches the maximum value of 8.6 GPa as the CaO/MgO mass ratio is 0.71.

Effect of Burner Core Number on Properties of CVD Fused Silica Glass

CHEN Yanjun, ZHOU Qian, HUANG Yaosong

2021, 40(12):  4109-4117. 

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The effect of the number of burner cores on the properties of CVD fused silica glass was studied by numerical simulations. The distributions of temperature, OH^- concentration and SiO₂ concentration at the deposition surface for the five-core, seven-core and nine-core burners were discussed. The influence law of different hydrogen-oxygen equivalence ratios was also analyzed. The results show that compared with the five-core burner and seven-core burner, the nine-core burner obtains more uniform SiO₂ concentration distribution and temperature distribution at the deposition surface. When a nine-core burner is used, a hydrogen-oxygen equivalence ratio of 1.5 improves the distribution uniformity of temperature, OH^- concentration and SiO₂ concentration on the deposition surface, thus improving the refractive index uniformity of fused silica glass.

New Functional Materials

Effect of Adhesive Layer on Electromechanical Response Behavior of Macro Fiber Composites

SHEN Jie, SONG Jiachang, ZHOU Jing, ZHOU Jingjing, HUANG Rui, SHEN Bingfei

2021, 40(12):  4118-4127. 

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The effect of the bonding layer parameters on the electromechanical response behavior of macro fiber composites (MFC) was analyzed, from the perspective of mechanical and electrical coupling of functional materials. It is found that reducing the thickness and increasing the dielectric constant of the adhesive layer are beneficial to alleviate the dielectric mismatch phenomenon of MFC via the finite element simulation, increasing the effective electric field load and obtain high-voltage electrical performance. Reducing its elastic modulus can improve the deformation ability of MFC. The MFC were fabricated, the actuating and sensing performance were characterized. The experimental results are consistent with the simulation data. Reducing the thickness and elastic modulus of the adhesive layer, increasing its dielectric constant can increase its tip displacement and output voltage of MFC, and improve the actuating and sensing performance. The research provides guidance for the design of MFC for actuating and sensing.

Effect of Li⁺ Doping Concentration on Luminescence Characteristics of Sr₃ZnNb₂O₉:Eu³⁺ Phosphor

YUAN Gaofeng, CUI Ruirui, ZHANG Xin, DENG Chaoyong

2021, 40(12):  4128-4136. 

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Li⁺ can improve the luminous intensity and thermal stability of Sr₃ZnNb₂O₉:Eu³⁺ phosphor as a charge compensator. In this work, a series of Sr₃ZnNb₂O₉∶xEu³⁺, yLi⁺ (0≤x≤0.5, 0≤y≤0.5) phosphors were synthesized by high-temperature solid-phase reaction. In order to identify and describe the phase, luminescence characteristics and thermal stability of samples, XRD and luminescence spectra tests were carried out. The results show that the Eu³⁺ and Li⁺ are successfully incorporated into the matrix material and replaced Zn²⁺ sites. The optimal doping concentration of Li⁺ is 0.3 (mole fraction), and the type of the concentration quenching mechanism is between the nearest neighbor ions. The Li⁺ doping improves the thermal stability of phosphors. The activation energy is 0.193 eV, and the CIE color coordinate is (0.651, 0.349), which is very close to the standard color coordinate specified by the International Commission on Illumination.

Preparation and Photoelectrocatalytic Perfermance of Bi₂MoO₆@CQDs/TiO₂ Nanotube Arrays

ZHANG Dalong, HE Shuo, LIN Zuxiang, DAI Gaopeng, LIU Suqin, XIAO Zuoan, CAI Shuang

2021, 40(12):  4137-4143. 

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In this work, TiO₂ nanotube arrays (TNA) were modified through the incorporation of Bi₂MoO₆ and carbon quantum dots (CQDs), to improve the visible light photocatalytic activity of TiO₂. The CQDs, Bi(NO₃)₃·5H₂O, and Na₂MoO₄ were used as the starting materials, a facile solvothermal method was employed to fabricate the novel Bi₂MoO₆@CQDs/TNA composite through the deposition of CQDs and Bi₂MoO₆ into the TNA. Based on the SEM and elemental mapping results, CQD and Bi₂MoO₆ are successfully coated on the tube wall of TNA. Moreover, the photocatalytic performance of Bi₂MoO₆@CQDs/TNA composite was investigated through the degradation of methyorange (MO) solution under the visible light irradiation. The corresponding photoelelctrocatalytic test results confirm that the as-prepared Bi₂MoO₆@CQDs/TNA exhibits an enhanced photoelectrocatalytic activity. Bi₂MoO₆@CQDs/TNA has a 32% higher removal rate of MO than Bi₂MoO₆/TNA. The enhanced activity can be attributed to the excellent up-conversion photoluminescence (UCPL) of CQDs, promoting TiO₂ to generate photogenerated carriers under the visible light. Meanwhile, the heterojunction between Bi₂MoO₆ and TiO₂ can also effectively inhibit the recombination of photogenerated carriers.

Preparation of CdTe Nanoparticles and Electron Transfer Mechanism with GSH

LIN Yanhui, BIAN Liang, SONG Mianxin, DONG Faqin, CAO Qilong, LI Weimin, LI Hailong, LI Yu, LUO Weige, ZHANG Jinmei, ZHANG Qin, ZHANG Jiao, LUO Weihui, YANG Min

2021, 40(12):  4144-4150. 

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CdTe nanoparticles were prepared by co-precipitation reduction method with CdCl₂·2.5H₂O as cadmium source, TeO₂ as tellurium source and hydrazine hydrate as reducing agent. The morphology, structure and optical absorption properties of CdTe nanoparticles were characterized by scanning electron microscopy, X-ray diffractometer, Raman spectrometer, Fourier infrared spectrometer and solid ultraviolet-visible spectrometer. The results show that the CdTe prepared at water bath temperature of 80 ℃, water bath time of 6 h, sintering temperature of 400 ℃, sintering time of 2 h has high crystallinity and good light absorption. The fluorescence spectra show that the fluorescence intensity of CdTe solution increases with the increase of glutathione (GSH) concentration, and the detection limit (LOD) is 0.004 mmol/L in the range of 0.005~0.8 mmol/L. This study provides a new technology for the preparation of CdTe fluorescence detector and a theoretical basis for explaining the fluorescence response of GSH in CdTe solution.

Road Materials

Anti-Cracking Performance of Basalt Warp Knitted Fiber Cloth Based on Reflection Crack Prevention

SHEN Aiqin, LONG Hongjun, GUO Yinchuan, LI Peng, ZHAI Chaowei

2021, 40(12):  4151-4157. 

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Reflective crack is the main reason for reducing the service life of semi-rigid base asphalt pavement, and laying geosynthetics is one of the effective ways to reduce reflective crack. To take optimum measures of reflective resistance, aimed at the problem of slight reflection crack in asphalt pavement surface, the anti-cracking performance of basalt warp knitted fiber cloth was studied. Through impact ductility test and dynamic fatigue test, the reflective resistance performances of basalt warp knitted fiber cloth and control geosynthetics (fiberglass grating and fiberglass-polyester paving mat) were analyzed. Finally, the correlation between impact ductility and fatigue properties of asphalt mixture after paving different geosynthetics was analyzed. The results show that the impact ductility of asphalt mixture is improved by more than 70% when basalt warp knitted fiber cloth is overlaying. Basalt warp knitted fiber cloth is superior to fiberglass grating and fiberglass-polyester paving mat in preventing crack generation and delaying crack propagation, and laying basalt warp knitted fiber cloth in asphalt mixture obtains the best fatigue properties. After paving geosynthetics, the impact ductility of asphalt mixture has a good correlation with its fatigue life, and it is feasible to use impact ductility to predict the fatigue properties of asphalt mixture after paving geosynthetics.

Properties and Microscopic Mechanism of PAPI Type Polyurethane Modified Asphalt

WANG Li, ZHANG Zengping, ZHU Youxin, LIU Hao, CHEN Liqi, BAN Xiaoyi

2021, 40(12):  4158-4166. 

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In order to study the modification mechanism of polyurethane (PU) on asphalt, two kinds of PU prepolymers were synthesized from polymethylene polyphenyl polyisocyanate (PAPI), polyglycol adipate diol (PEA) and polytetrahydrofuran (PTMEG), which were used to prepare PU modified asphalt. The basic properties of modified asphalt were tested by penetration test, softening point test, ductility test and viscosity test, and the microstructure and reaction mechanism of modified asphalt were analyzed by fourier transform infrared spectroscopy (FTIR), atomic force microscope (AFM), thermogravimetric (TG) analysis and differential scanning calorimetry (DSC).The results show that PAPI type PU improves the high and low temperature performances of asphalt through physical and chemical reactions. The addition of PU reduces the penetration of asphalt by more than 20%, improves the softening point by more than 35%, and improves the ductility by more than 350%. Both PU modifiers significantly improve the viscosity of asphalt. PU reacts with asphalt to form PU-asphalt grafts to improve compatibility, resulting in a change in the ratio of functional groups of modified asphalt. The incorporation of PU increases the height of the bee-shaped structure in the asphalt, thereby improving the high temperature performance of the asphalt. PAPI-PEA type PU modified asphalt has better thermal stability than PAPI-PTMEG type PU modified asphalt, while PAPI-PTMEG type PU modified asphalt has a lower glass transition temperature.

Properties of Asphalt Modified by Aluminum Trihydrate/Organic Montmorillonite Composite

JIA Xiaojun, SHEN Aiqin, WANG Chao, GUO Yinchuan, WANG Han, YANG Xiaolong, WU Hansong

2021, 40(12):  4167-4177. 

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The objective of this research is to develop a flame retardant asphalt modified by aluminum trihydrate (ATH) and two kinds of organic montmorillonites (OMMT-C, OMMT-F) and investigate the effect of ATH/OMMT composite flame retardant on properties of styrene-butadiene-styrene (SBS) modified asphalt. The conventional performance of ATH/OMMT modified asphalt was evaluated by testing penetration, softening point and ductility. The limit oxygen index (LOI) and smoke density (SDR) were obtained to investigate the flame retardant and smoke suppression performance of ATH/OMMT modified asphalt. The optimum content of ATH/OMMT composite flame retardant was determined based on the comprehensive index method. The rheological properties of ATH/OMMT modified asphalt were investigated by dynamic shear rheological (DSR) test. The pyrolysis and combustion characteristics of ATH/OMMT modified asphalt were analyzed by thermogravimetric (TG) test. The results reveal that ATH/OMMT composite flame retardant increases the softening point and reduces the low temperature performance of SBS modified asphalt. However, the flame retardant and smoke suppression performance are greatly enhanced by the additive of ATH/OMMT composite flame retardant. The initial decomposition temperature of the composite modified asphalt is 3 ℃ to 6 ℃ higher than that of SBS modified asphalt. When the ATH content is 10% (mass fraction) and the OMMT-C content is 3% (mass fraction), LOI value of asphalt is more than 23%. At the same time, the smoke density of asphalt is reduced by 33.9%. Compared with SBS modified asphalt, the decomposition residual rate of composite modified asphalt increases up to 61.3%. ATH/OMMT-C composite flame retardant significantly increases the complex modulus and rutting factor, and improves the deformation resistance of asphalt at high temperature.

Surface Oxidation Mechanism of Crumb Rubber and Its Effect on Storage Stability of Crumb Rubber-Modified Asphalt

CHENG Yong, LIU Yumei, JU Jian, ZHENG Mulian, PAN Xifeng, ZHU Yueming

2021, 40(12):  4178-4186. 

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In order to enhance the surface activity of crumb rubber and improve the storage stability of crumb rubber-modified asphalt, H₂O₂ and NaClO solutions were used to oxidize waste crumb rubber powder and the catalytic effect of FeSO₄·7H₂O on the oxidation process of H₂O₂ solution was investigated. The microstructures of crumb rubber before and after oxidation were studied by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The storage stability of crumb rubber-modified asphalt was characterized by 48 h segregation test. The results show that the surface active oxygen-containing groups of crumb rubber increase and the microstructures change under the action of two oxidants. The main elements of the powder before and after oxidation are C, O and S. The relative content of O on the surface of oxidized crumb rubber increases significantly. Besides, the storage stability of crumb rubber-modified asphalt oxidized by H₂O₂-FeSO₄ solution is significantly improved, which meets the requirements of polymer-modified asphalt in China.

Recycling Law of Aged Asphalt Based on Diffusion Behavior of Rejuvenator/Virgin Asphalt

XU Jinzhi, ZHANG Binjun, ZHANG Depeng

2021, 40(12):  4187-4196. 

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Tube method was used to simulate the diffusion of rejuvenator/virgin asphalt in aged asphalt. The formed rejuvenated asphalt in different layers were cut out for testing of conventional indexes, rheological properties and temperature susceptibility, so as to evaluate the variation laws of technical performance for rejuvenated asphalt with diffusion process of rejuvenator/virgin asphalt. In addition, the influencing mechanism of temperature and time on diffusion behavior of rejuvenator/virgin asphalt was also carried out. The results show that the performances of rejuvenated asphalt in different layers are restored to varying degrees and display gradient trend with the diffusion of rejuvenator/virgin asphalt. The farther away from the interface between virgin asphalt and aged asphalt, the closer the performance is to the aged asphalt. In the same diffusion position, RA-1 rejuvenator shows better diffusion ability and rejuvenating effect than virgin asphalt SK-90, especially in terms of improvement of cracking resistance at low temperature for rejuvenated asphalt. The increase of mixing temperature and extension of diffusion time within certain range are conducive to enhancing the diffusion ability of rejuvenator/virgin asphalt in aged asphalt and promoting the blending between virgin and aged asphalt.

Interlayer Shear Performance of Steel SlagAsphalt Mixture Thin Overlay

LUO Cheng, YAN Feng, XIA Haiting, LU Kaiyu, ZHOU Bin, FENG Mingjie

2021, 40(12):  4197-4208. 

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In order to explore the shear failure mechanism between thin overlay of steel slag asphalt mixture, a gap graded steel slag thin asphalt overlay and dense graded surface layers with different texture depth were designed. The effects of texture depth, temperature, styrene-butadiene rubber modified emulsified asphalt dosage and stress ratio on shear performance between thin layers of steel slag were studied. Marshall stability test, freeze-thaw splitting test and dynamic stability test were used to evaluate the road performance of asphalt mixture. Direct shear test and shear fatigue test were used to evaluate the interlayer shear performance between thin overlay and surface layers. The results show that the crushing value and abrasion of steel slag aggregate are obviously lower than those of limestone aggregate, and the adhesion of steel slag/asphalt is much better than that of limestone/asphalt, which makes the pavement performance of steel slag asphalt mixture excellent. Interlayer shear strength is mainly controlled by test temperature. At the same temperature, the interlayer contact state between the surface layer and the thin overlay is improved with increase of tack coat application rate, the shear strength is improved. However, excessive tack coat forms slip layer between the surface layer and the thin overlay, which weakened the influence of the texture depth on interlayer shear strength. Through shear fatigue test, the shear fatigue life of thin overlay decreases with the increase of stress ratio. The fatigue life equation is obtained by shear fatigue test.

Effect of Vibration Mixing on Iron Tailing Cement Stabilized Macadam Mixture

WANG Hongguo, SU Jizhuang, ZHANG Min, JI Ping, WANG Xinyang, LIU Jian

2021, 40(12):  4209-4216. 

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In order to analyze the factors of the pavement performance of the cement stabilized macadam mixture with iron tailings, the mechanical strength, water stability, frost resistance and fatigue resistance of cement stabilized macadam mixture compacted by the different iron tailing content (0%, 5%, 10%, 15%, 20%, 25%) and different mixing method(static mixing, vibration mixing) were researched. The results show that the iron tailings improve the unconfined compressive strength, indirect tensile strength, water stability and frost resistance of cement stabilized macadam mixture. When the content of iron tailings is 10%, the mechanical strength, water stability and frost resistance of the cement stabilized macadam mixture reach the maximum. When the content of iron tailings is 5%, the fatigue life of the cement stabilized macadam mixture reaches the longest. The samples prepared by the vibration mixing have higher strength, water stability, frost resistance, and fatigue resistance. At the same time, the cement hydration degree inside the mixture is higher, and the distribution of hydration products is more uniform, which reduces the risk of damage to the mixture due to stress concentration.