Article
Energy & Fuels
Qianwen Dong, Bing Sun, Zhijun Dong, Yongsheng Tian, Hui Zhu, Guanming Yuan, Ye Cong, Baoliu Li, Jianguang Guo, Xuanke Li
Summary: A novel strategy is proposed in this study to prepare EG/PW binary PCCs with high thermal conductivity and excellent phase change behavior by constructing highly oriented graphite sheets inside the composites. The resulting EG/PW PCCs exhibit significantly improved thermal conductivity and excellent compatibility, uniformity, thermostability, and reliability.
Article
Energy & Fuels
Anirban Chakraborty, Juran Noh, Robert Mach, Patrick Shamberger, Choongho Yu
Summary: The article introduces a preform-type expanded graphite (EG)/paraffin wax composite with highly reliable heat transfer and storage properties, even after 10,000 melt/freeze cycles. The authors conducted comparative studies on the combined influence of fabrication process, particle size, EG vol%, binder amount, and compaction on both magnitude and robustness of thermal conductivity.
JOURNAL OF ENERGY STORAGE
(2022)
Article
Energy & Fuels
Ruilong Wen, Maomao Wu, Bojun Chen, Weixing Chen
Summary: The non-isothermal crystallization behavior of Ag nanoparticles modified expanded graphite/paraffin composited PCMs was studied. It was found that expanded graphite accelerated the crystallization of paraffin wax, while surface interaction between Ag and paraffin wax restricted its crystallization.
JOURNAL OF ENERGY STORAGE
(2023)
Article
Energy & Fuels
Dongyin Niu, Yufei Tan, Tiantian Zhang, XueDan Zhang, Wensheng Zhang
Summary: In this paper, a novel phase-change heat storage electric heating system was studied, and an electric heating module was fabricated using a composite phase change material and carbon fiber heating wire. Experimental results showed that the module can meet the heating requirements of buildings, and it exhibits good thermal stability and reliability.
JOURNAL OF ENERGY STORAGE
(2022)
Article
Construction & Building Technology
Waldemar Pichor, Maksymilian Frac, Marta Radecka
Summary: This study presents a method for determining the percolation threshold in cement composites with expanded graphite using impedance spectroscopy. The results suggest that this method is effective for cement composites with conductive additives, helping to address issues related to electrical properties.
CEMENT & CONCRETE COMPOSITES
(2022)
Article
Chemistry, Multidisciplinary
Xudong Tang, Jiaming Zhang, Jingwen Wang, Tao Xu, Yanliang Du, Gan Fan, Huijun Wu
Summary: The application of phase change material (PCM) floor in a radiant heating system can improve indoor comfort with high energy efficiency and economic benefits. This study developed a novel PCM floor by mixing paraffin/expanded graphite composite PCM (CPCM) with building cements, and evaluated its practical performance in a solar-heat pump combined radiant heating system. The optimal mass fraction of CPCM in the PCM floor was determined as 35%. Experimental measurements and TRNSYS simulations demonstrated that the PCM floor significantly enhanced indoor comfort and had positive energy and economic impacts.
ACS SUSTAINABLE CHEMISTRY & ENGINEERING
(2023)
Article
Thermodynamics
Alexander Bulk, Adewale Odukomaiya, Ethan Simmons, Jason Woods
Summary: This article evaluates the effect of heat treatment process on PCM saturation and overall matrix thermal conductivity in expanded intercalated graphite flakes. Higher heat treatment temperatures and longer soaking time can increase saturation rate, while exposure time has little effect on saturation. Heat treatment conditions do not impact thermal conductivity, and the composite latent heat of fusion decreases with the increase in PCM mass fraction.
JOURNAL OF THERMAL SCIENCE
(2023)
Article
Green & Sustainable Science & Technology
Bohui Lu, Yongxue Zhang, Dong Sun, Xiaolei Jing
Summary: The study prepared paraffin/expanded graphite composite phase change materials, which showed improved thermal conductivity and melting temperature by adding expanded graphite. The fabrication process of the composite PCMs was determined to be purely physical without generating new substances.
Article
Energy & Fuels
Yang Li, Zaiguo Fu, Mingxing Xue, Zhixiong Shao, Yan Li, Qunzhi Zhu
Summary: This study investigates the application of a shape-stabilized phase change material (SSPCM) made by mixing paraffin wax with expanded graphite in heat storage systems. The SSPCM demonstrated high thermal conductivity and suitable density, resulting in a thermal efficiency of 95.3% for the heat storage system.
Article
Energy & Fuels
Awni H. Alkhazaleh, Waref Almanaseer, Mohammad Ismail, Sahar Almashaqbeh, M. M. Farid
Summary: The thermal storage composite produced in this research, which integrates a novel eutectic phase change material into supporting material, shows promising potential for reducing energy consumption and improving indoor thermal temperature in building envelope. The composite exhibits appropriate phase change temperature and latent heat fusion, and demonstrates good thermal stability within a certain temperature range.
JOURNAL OF ENERGY STORAGE
(2022)
Article
Materials Science, Multidisciplinary
Majid Shaker, Qin Qin, DaWa Zhaxi, Xianyong Chen, Kefan Chen, Shuai Yang, Hao Tian, Weiqi Cao
Summary: The research compares the thermal energy storage of graphene/paraffin and expanded graphite/paraffin composites for low-temperature applications and explores the roles of graphene and expanded graphite in thermal energy storage. The composites show efficient absorption of the phase change material with minimal decrease in latent heat of fusion. Additionally, the thermal conductivities of the expanded graphite-Pn5 and graphene-Pn5 composites are significantly higher than that of pure Pn5. The graphene-Pn5 composite exhibits excellent thermal conductivity, satisfactory phase change temperature, and superb latent heat storage capacity, making it suitable for cold thermal energy storage applications.
JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
(2023)
Article
Energy & Fuels
Y. Li, S. H. Zhou, S. Wang, K. Q. Ma, Q. Z. Zhu
Summary: In this study, a novel ternary mixed molten salt of NaNO3-LiNO3-NaCl with high latent heat was prepared and studied to improve the thermal properties of nitrate in medium temperature thermal storage. Experimental results showed that compared with pure NaNO3, the phase change temperature of NaNO3-LiNO3-NaCl was reduced by 45.3 degrees C, and the latent heat of phase change was increased by 59.4 J/g. The addition of expanded graphite (EG) as the carrier adsorption material greatly improved the heat transfer capacity of the ternary molten salt, making NaNO3-LiNO3-NaCl/EG have broad application prospects in the field of medium and high temperature heat storage.
JOURNAL OF ENERGY STORAGE
(2023)
Article
Energy & Fuels
Chao Ma, Jing Wang, Yu Wu, Yongchao Wang, Zhijiang Ji, Shuai Xie
Summary: The main aim of this paper is to enhance the thermal conductivity of erythritol as phase change material. By incorporating expanded graphite and calcium pimelate, the composite PCM shows improved cycle stability and significantly enhanced thermal conductivity, making it a promising candidate for waste heat recovery and solar energy medium temperature heat collection.
JOURNAL OF ENERGY STORAGE
(2022)
Article
Construction & Building Technology
Jian Wei, Dongming Gao, Yuan Wang, Xueting Li, Yupeng Guo, Yi Yao
Summary: The deterioration of traffic safety caused by high road temperatures and increased transport costs has necessitated the need for road users to reduce the temperature of the road surface. This study focuses on the development of high thermal conductivity diamond/ZnO/expanded graphite (D/ZnO/EG)1 cement-based composites to achieve road cooling. The results showed that the D/ZnO/EG composite significantly improved heat transfer, reduced pavement temperatures, and prevented thermal conductivity damage caused by freeze-thaw cycles.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Chemistry, Physical
Jinghao Lin, Yuexing Ouyang, Lan Chen, Kai Wen, Yan Li, Haoze Mu, Qinglei Ren, Xiaozhu Xie, Jiangyou Long
Summary: This study successfully enhanced the solar absorption capacity of EG-paraffin wax composite PCMs by adding CNTs, while maintaining good thermal conductivity and latent heat. This high-performance composite PCM has potential importance in solar-thermal conversion applications.
SURFACES AND INTERFACES
(2022)
Article
Construction & Building Technology
Waldemar Pichor, Maksymilian Frac, Marta Radecka
Summary: This study presents a method for determining the percolation threshold in cement composites with expanded graphite using impedance spectroscopy. The results suggest that this method is effective for cement composites with conductive additives, helping to address issues related to electrical properties.
CEMENT & CONCRETE COMPOSITES
(2022)
Article
Chemistry, Physical
Maciej Sypek, Rafal Latawiec, Beata Lazniewska-Piekarczyk, Waldemar Pichor
Summary: This paper evaluates the influence of calcium sulfate on the air void microstructure in concrete and proposes its action mechanism may depend on the character of the air-entraining agent. Gypsum dehydration is confirmed to negatively affect the air void structure. The study concludes that air entrainment has a twofold mechanism, with the adsorptive mechanism being more effective in terms of total air content and air void structure.
Article
Chemistry, Physical
Wojciech Szudek, Lukasz Golek, Grzegorz Malata, Zdzislaw Pytel
Summary: The study found that in lime quartz samples where ground quartz sand was gradually substituted with waste glass powder, a higher amount of amorphous and semi-crystalline C-S-H phase formed, while the addition of GP hindered the formation of tobermorite.
Article
Construction & Building Technology
Maksymilian Frac, Wojciech Szudek, Paulina Szoldra, Waldemar Pichor
Summary: The research results indicate that shungite is a promising conductive additive for cement composites. Introduction of at least 16% of shungite allows obtaining composites with electrical properties, enabling their application in stress/damage or temperature monitoring. Cement composites with shungite also exhibit piezoresistive and thermoelectric effects.
JOURNAL OF BUILDING ENGINEERING
(2022)
Article
Chemistry, Physical
Lukasz P. Golek, Wojciech Szudek, Michal Malik
Summary: In this study, ground granulated blast furnace slag was activated with various sodium salts to investigate their impact on hydration progress and compressive strength development. The presence of sodium ions was found to be more significant than the pH of the system, even when the compounds had low pH values.
Article
Chemistry, Physical
Kornelia Wisniewska, Ewelina Klosek-Wawrzyn, Radoslaw Lach, Waldemar Pichor
Summary: The study found that the addition of calcium carbonate alters the color properties of the materials, increasing the yellow color factor while decreasing the red color factor and brightness. Additionally, the grain size distribution of the additive significantly influences the phase composition of the materials and their color properties.
Article
Chemistry, Physical
Maksymilian Frac, Paulina Szoldra, Waldemar Pichor
Summary: The objective of this study was to obtain cement composites with low percolation thresholds by using exfoliated graphite as a conductive additive. The results showed that the incorporation of exfoliated graphite is an effective way to achieve a percolation threshold as low as 0.96%, while maintaining satisfactory mechanical properties and practical application potential.
Article
Chemistry, Physical
Agnieszka Michalik, Filip Chylinski, Jan Bobrowicz, Waldemar Pichor
Summary: The role of searching for industrial waste management solutions in construction is crucial for environmental protection. This paper presents the results of tests conducted on concrete reinforced with treated recycled tyre steel fibres (RTSFs) compared to the same amount of manufactured steel fibres (MSFs). The effectiveness of concrete reinforcement with RTSFs was analysed using fracture mechanics parameters, and various tests were performed to evaluate the properties of RTSFs reinforced concrete. The study found that RTSFs reinforced concrete, purified and refined during the recycling process, may have better properties than MSFs reinforced concrete. The application of RTSFs in construction not only strengthens cementitious composites but also offers environmental and economic benefits.
Article
Materials Science, Multidisciplinary
Paulina Szoldra, Maksymilian Frac, Radoslaw Lach, Lukasz Zych, Marta Radecka, Anita Trenczek-Zajac, Waldemar Pichor
Summary: This paper presents the synthesis and properties of nanometric TiO2 powders obtained by the sol-gel method at elevated temperatures. The presence of brookite inhibits the anatase-rutile transformation at higher temperatures. Even after the treatment of gel at 700 degrees C, a large amount of anatase in the TiO2 powders was found. Measurements in the UV-vis range were performed to determine the optical band-gap of TiO2. Results of photocatalytic tests for the degradation of RhB and NO under UV are also presented. The obtained powders despite being prepared at this temperature were more efficient in both RhB and NO decomposition compared to the reference sample. The results indicate the possibility of modifying materials that are produced or work at high temperatures, by adding TiO2 with high photocatalytic capacity in the UV range.
MATERIALS SCIENCE AND ENGINEERING B-ADVANCED FUNCTIONAL SOLID-STATE MATERIALS
(2023)
Article
Construction & Building Technology
Sylwia Kucharczyk, Waldemar Pichor
Summary: The study evaluated the use of ground waste-expanded perlite (WP) as a sustainable replacement for ground granulated blast-furnace slag (GGBFS) in alkali-activated systems. The results showed that WP can be successfully used as a partial replacement for GGBFS, with activation by sodium carbonate being more beneficial in terms of compressive strength. The incorporation of WP into Na2CO3 activated systems resulted in a reduction in performance development, especially at early ages, and the presence of a sodium-rich C(-N)-S-H.
MATERIALS AND STRUCTURES
(2023)
Article
Construction & Building Technology
Maciej Sypek, Rafal Latawiec, Grzegorz Loj, Waldemar Pichor
Summary: This paper investigates the role of tricalcium aluminate (C(3)A) and gypsum dehydration level in the air-entraining mechanism in concrete. A higher-performance air system can be achieved by using anionic surfactant, higher C(3)A content, and preventing gypsum dehydration. Adsorption on cement particles dominates the air-entraining mechanism when anionic admixture is used. Despite lower surface tension reduction, anionic surfactant performs higher quality air microstructure. The adsorption of admixture plays a major role in the effective air-entraining mechanism process.
ROAD MATERIALS AND PAVEMENT DESIGN
(2023)
Article
Chemistry, Physical
Ewelina Klosek-Wawrzyn, Maksymilian Frac, Waldemar Pichor
Summary: This study used a pregranulation process to produce ceramic materials by granulating spent coffee grounds with clay. The pregranulation process overcomes the challenges of incorporating large quantities of spent coffee grounds and the drying shrinkage issue. The results demonstrate that the pregranulated ceramic materials have excellent thermal insulation properties and sufficient strength.
APPLIED CLAY SCIENCE
(2023)
Article
Construction & Building Technology
Qi Jiang, Wei Liu, Shaopeng Wu, Xuanwen Gou
Summary: This study analyzes the erosion mechanisms of NaCl solution on asphalt concrete and finds that NaCl solution softens asphalt and promotes the intrusion of crystalline salt into it. Salt crystallization alters the surface roughness of aggregates, resulting in a decrease in skid resistance but an improvement in compressive strength. Additionally, the concentration of NaCl solution initially has no significant impact on the mechanical performance of asphalt concrete, but its domination gradually increases with the intensification of cyclic effects.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Lili Kan, Lan-qing Dai, Ning Kong, Bin Peng, Fei Wang
Summary: This paper investigates the effect of freezing and thawing cycles on the tensile behavior of cracked ultra-high performance concrete (UHPC). The results show that long-term freezing and thawing action deteriorates the cracking strength, tensile strength, tensile strain, and strain energy of cracked UHPC. On the other hand, the action of water generally favors the development of tensile properties of UHPC. The crack distribution tends to be unsaturated under freezing and thawing environment, and the re-hydration reaction is hindered. The pore structure near the crack varies under different environments.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Xin Xiao, Jingwei Li, Qingke Meng, Xiangshan Hou, Yanhui Liu, Xujiang Wang, Wenlong Wang, Shengtao Lu, Yuzhong Li, Yanpeng Mao, Tong Li
Summary: Preparing gypsum-based self-leveling mortar (GSLM) using beta-hemihydrate gypsum and solid wastes-derived sulfoaluminate cement (WSAC) can improve the mechanical performance of the mortar, but phosphorus impurities can weaken the hydration speed and degree.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Sihang Bao, Junzhen Di, Yanrong Dong, Ziqing Gao, Qing Gu, Yuanfang Zhao, Hongyu Zhai
Summary: Tailings dam break and leakage accidents pose a threat to the safety of people in mining areas and cause severe environmental pollution. This study focuses on solidifying tailing sand using microbial induced calcite precipitation (MICP) to improve strength and fix heavy metals. The curing time of MICP bio-cemented tailings is found to significantly impact the strength of tailings, while its effect on heavy metal fixation is minimal. The optimized MICP curing time is 10 days, resulting in improved strength and cementation of tailings particles.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Ferhat Benmahiddine, Fares Bennai, Achraf Charaka, Ameur El Amine Hamami, Abdelkader Tahakourt, Rafik Belarbi
Summary: This paper studied the effects of hysteresis on the hygrothermal behavior at the building scale. Through laboratory validation and numerical simulations, it was found that hysteresis has a significant impact on the relative humidity and total heat fluxes in buildings, while it does not have a noticeable effect on temperature variations.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
You Gao, Wei He, Xiayang Zhang, De'an Sun, Pei Li
Summary: This study determined the boundary line between the swelling and compression deformation zone in lateritic clay through wetting tests, and proposed a simple bimodal SWRC model. It also found that the existing strength model underestimated the tested values in the medium to high suction range, therefore a segmented strength equation was introduced for enhanced predictions of the strength properties of lateritic clay.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Prabhath Ranjan Kumar Soda, Asheer Mogal, Kalyan Chakravarthy, Nikhil Thota, Nimish Bandaru, Sanjay Kumar Shukla, K. M. Mini
Summary: This study investigates the use of encapsulated bacteria to improve the self-healing ability of concrete. Through various tests, it is found that using 20% cement-coated alginate beads (CCAB) and 5% nanosilica (NS) can achieve optimal strength and healing. This research is significant for enhancing the durability of concrete.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Shizhe Wang, Haiping Wu, Wen Yang, Wei Wang, Zhibo Zhu, Kun Nie, Luoxin Wang, Hua Wang, Jing Wu
Summary: In this study, photothermal-heat storage concrete (PHSC) was developed with excellent photothermal conversion performance and heat storage capacity. By absorbing and storing solar energy during the day and releasing it at night, PHSC can effectively reduce energy consumption in buildings.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Robin Deb, Jialuo He, Geetika Mishra, Yaghoob (Amir) Farnam
Summary: Incorporation techniques of phase change materials in cementitious composites have a significant influence on thermal properties. This study investigated the thermal behavior of low-temperature PCM when subjected to varying temperature change rates and pore confinement inside the porous network of lightweight aggregates. The results showed that ramp rates affect the nucleation and crystallization growth process during the phase transition, and the pore structure of the aggregates affects the supercooling phenomenon and confinement pressure of the PCM.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Eduardo Ferreira, Payam Sotoudeh, Dagmar Svecova
Summary: This study investigates the fatigue behavior of concrete under different stress reversal conditions. The results indicate that stress reversal generally causes more severe damage and reduces the cycles to failure compared to tensile fatigue. Additionally, adding some level of compression contributes to the energy required for failure under stress reversal fatigue. Specimens with higher concentration of fractured aggregates achieve longer fatigue lives.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Mag Raj Gehlot, Sandeep Shrivastava
Summary: This study evaluates the compatibility relationship between plaster bonds and the substrate under an accelerated aging environment, and finds that incorporating an appropriate amount of granite cutting waste can improve the strength parameters and adhesion of the cement mortar.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Min Zhang, Qirui Luo, Mingke Deng, Shixing Zhao
Summary: This study investigated the bond behavior between carbon FRCM composites with added short fibers and concrete substrates. The effects of different factors were considered and 36 specimens were tested and discussed. The experimental results were analyzed in terms of failure mode, load-slip curve, and characteristic parameters, and the contribution of weft yarns was taken into account in the developed bondslip model.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Dengkai Liu, Hongniao Chen, Ray Kai Leung Su
Summary: The susceptibility of building stones to fire and high temperature was investigated in this study by examining their physical and mechanical properties. The results show that both compressive and tensile properties of stones are affected by temperature changes. The tensile strength is particularly sensitive to temperature changes, requiring special attention to the components subjected to tensile stress in stone buildings. Principal component analysis was used to predict the mechanical properties of stones, providing a new method for calculating the residual mechanical properties after high temperature or fire.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Joso Maria Raposo, Eduardo Cavaco, Luis Costa Neves, Eduardo Julio
Summary: This paper investigates the correlation between the friction coefficient and the surface roughness of concrete-to-concrete interfaces. Experimental tests were performed on specimens with different surface treatments, and the surface roughness parameters were analyzed and correlated with the shear strength and friction coefficient. The results showed that certain roughness parameters had a strong positive correlation with the friction coefficient, while others had little or no correlation. A novel combined roughness parameter with optimized correlation was proposed.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
Article
Construction & Building Technology
Chiara Riccardi, Massimo Losa
Summary: The interest in using bio materials in asphalt pavements is growing due to economic reasons and environmental benefits. This study aimed to review the use of bio extenders as additives in binders, with a focus on replacements greater than 20% of fossil binder. The properties of bio-extended binders were found to vary substantially depending on the biomass source and production process.
CONSTRUCTION AND BUILDING MATERIALS
(2024)
