Article
Thermodynamics
Muhammad Ghufran, David Huitink
Summary: Paraffin- and titania-based nano-encapsulated phase change materials (NePCMs) were synthesized by the sol-gel process to improve thermal and phase change performance. Nine different samples of NePCMs were prepared with varying core/shell mass ratios, and their effect on thermal performance was investigated. Characterization techniques confirmed the successful encapsulation of paraffin in the titania shell. The NePCMs with a 52.33% encapsulation ratio exhibited the maximum effective melting and solidification latent heat. The thermal properties of the NePCMs remained stable even after 100 thermal cycles, and their thermal stability was evaluated using a thermogravimetric analyzer.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2023)
Article
Materials Science, Ceramics
Amira M. EL-Rafei
Summary: In this study, different forms of silica fume waste were used to prepare silica-based products. The results showed that the preparation of mesoporous nano-silica from silica fume without using a template and the needed post-heated treatment to get rid of it is an energy-saving technology.
CERAMICS INTERNATIONAL
(2022)
Article
Construction & Building Technology
Long Li, Dongxing Xuan, S. H. Chu, Chi Sun Poon
Summary: This study aimed to enhance the mechanical properties and durability of recycled aggregate concrete (RAC) by spraying colloidal nano silica (NS) and silica fume (SF) on the surface of recycled coarse aggregate (RCA), with larger particle sizes of NS showing more significant performance enhancement. The research found that spraying colloidal SF on RCA improved both the new mortar and new interfacial transition zone (ITZ) in RAC, while spraying colloidal NS only enhanced the new ITZ.
MATERIALS AND STRUCTURES
(2021)
Article
Construction & Building Technology
John Paul, Mahendran Samykano, Adarsh Kumar Pandey, Kumaran Kadirgama, Vineet Veer Tyagi
Summary: Recent research has shown that adding nano additives to phase-change materials can enhance the latent heat and heat storage efficiency, as well as improve thermal conductivity, which is significant for building thermal management.
Article
Chemistry, Multidisciplinary
Tang Yunchao, Chen Zheng, Feng Wanhui, Nong Yumei, Li Cong, Chen Jieming
Summary: The combination of silica fume and nano-silica as additives improves the performance of recycled aggregate concrete in both early and later stages. These additives exhibit good pozzolanic activity, enhancing the secondary hydration reaction with calcium hydroxide to improve the properties of the interface transition zone.
NANOTECHNOLOGY REVIEWS
(2021)
Article
Engineering, Mechanical
Mohammad Ghalambaz, Haichuan Jin, Amirhossein Bagheri, Obai Younis, Dongsheng Wen
Summary: Nano-encapsulated phase change suspension is a novel functional fluid that utilizes the phase change of nanoparticles for heat transfer. In this study, the natural convection and heat transfer of NEPCMs suspensions along a heated flat surface in a boundary layer are investigated. The results demonstrate that the temperature at which NEPCM particles undergo phase transition is a decisive factor in enhancing heat transfer, with a 25% improvement achievable by adding only 5% of NEPCM particles.
FACTA UNIVERSITATIS-SERIES MECHANICAL ENGINEERING
(2022)
Article
Construction & Building Technology
Fei Wang, Wukui Zheng, Zhigang Qiao, Yongle Qi, Zili Chen, Hui Li
Summary: This study presents the preparation and investigation of a structural-functional lightweight aggregate concrete (LWAC) with novel hollow ceramsite (HC) compounded with paraffin. The mechanical and thermal properties of LWAC with HC-Paraffin are examined, and the stability of this novel energy storage concrete is evaluated through multiple thermal cycles. The results demonstrate that the LWAC with HC-Paraffin meets the requirements for structural building application, and exhibits good stability in terms of mechanical and thermal properties. This research provides a new method for the application of phase change materials (PCMs) in buildings.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Construction & Building Technology
Muhammad Zeeshan Haider, Xinghan Jin, Raju Sharma, Junjie Pei, Jong Wan Hu
Summary: In this study, a structural functional thermal energy storage concrete (TESC) containing Tetradecane as a low-temperature PCM was developed. The inclusion of PCM-LWAs in concrete resulted in a significant decrease in strength, which was mitigated by the addition of silica fume and multiwalled carbon nanotubes. The SEM and XRD results confirmed that the addition of SF/MWCNTs led to a denser microstructure and increased growth of C-S-H, improving the mechanical performance of the TESC containing PCM-LWAs.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Energy & Fuels
Abeer Alhashash, Habibis Saleh
Summary: The numerical study focused on the effect of heating exponent and frequency on the convective flow and melting distribution inside a square enclosure filled with hybrid nanofluid. The study used a Galerkin finite element method to solve the governing equations and compared the results with previously published articles. The research found that the lowest heating exponent and frequency resulted in the best thermal performance.
JOURNAL OF ENERGY STORAGE
(2023)
Article
Chemistry, Physical
Vicente Zetola, Luis J. Claros-Marfil, Alfonso Garcia Santos, Fco. Javier Neila Gonzalez
Summary: The study evaluated the effects of incorporating PCM based on paraffins into Portland cement mortar mixtures, showing that the PCM-added mixtures require more water and cement to achieve similar compressive strengths and result in a decrease in density. The maximum compressive strength was achieved with a 15% PCM content, while values beyond 40 MPa were obtained with 5% PCM content.
Article
Green & Sustainable Science & Technology
Wei Gao, Feifan Liu, Cheng Yu, Yongping Chen, Xiangdong Liu
Summary: Encapsulating phase change materials (PCMs) using microfluidic method enables the fabrication of efficient and stabilized PCMs with desired properties. This review comprehensively summarizes the recent advances in microfluidic method-based encapsulated PCMs (ME-PCMs), highlighting the technologies for fabrication of ME-PCM capsules and ME-PCM fibers, and examining their applications in thermal regulation, thermal response, and wearable electronics. Insights on future directions for large-scale applications are also provided, hoping to inspire novel and effective encapsulation methods for ME-PCMs.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2023)
Article
Crystallography
Shun Zhou, Xiaotao Zhang, Han Zhou, Dongxu Li
Summary: This research focused on the ternary effects of graphene oxide encapsulated silica fume (GOSF), nano-silica sol (SS), and fly ash (FA) on the properties of cement. The results showed that the combination of GOSF, SS, and FA had a synergistic effect and improved the performance of cement. At 28 days of curing age, the cement reached its peak compressive strength, with the lowest values of CH content and crystal size, water absorption, and porosity. Additionally, a denser structure of C-S-H gel and a regular arrangement of CH were observed.
Article
Thermodynamics
C. J. Ho, Yen-Chung Liu, Tien-Fu Yang, Mohammad Ghalambaz, Wei-Mon Yan
Summary: The phase change heat transfer of NEPCM particles can significantly enhance heat transfer efficiency at low Reynolds numbers and low heating powers, but its advantage over pure water diminishes at large Reynolds numbers.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2021)
Article
Construction & Building Technology
Xueting Wang, Huaxin Chen, Dongliang Kuang, Siyu Wu
Summary: This paper synthesized paraffin/ SiO2 micro-encapsulated phase change material (MPCM) and investigated its cooling effect in asphalt binder through various experiments. The results showed that MPCM had higher specific heat capacity and excellent thermal stability, making it applicable for cooling asphalt pavement. However, further research is needed to understand the rheological properties of MPCM in asphalt pavement.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Construction & Building Technology
Phattharachai Pongsopha, Piti Sukontasukkul, Buchit Maho, Darrakorn Intarabut, Tanakorn Phoo-ngernkham, Sakonwan Hanjitsuwan, Donguk Choi, Suchart Limkatanyu
Summary: The study showed that the ASF coating can effectively reduce PCM leakage, improve the mechanical properties of RC mixed with ASF-PCMA, and have positive and negative effects on the thermal conductivity of RC depending on the state of PCM.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Construction & Building Technology
Sher Afgan, Rao Arsalan Khushnood, Shazim Ali Memon, Naseem Iqbal
CONSTRUCTION AND BUILDING MATERIALS
(2019)
Article
Construction & Building Technology
Pei Yan, Bing Chen, Sher Afgan, M. Aminul Haque, Meng Wu, Jiaxing Han
Summary: This study aimed to enhance the ductility characteristics of ultra-high performance concrete fibre material by utilizing different micro-synthetic fibres. The type and amount of added fibres were found to influence the properties of both fresh and hardened concretes, with glass fibre having a notable impact on the flowability of fresh concrete. Additionally, the compressive strength increased with the addition of fibre filament, while flexural strength and toughness indexes also improved accordingly.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Review
Construction & Building Technology
Sher Afgan, Chen Bing
Summary: The study reviews the development trends and research results in the field of thermal energy storage cement-based composites, showing a gradual increase in related research articles from 1993 to 2020. Currently, only a small percentage of countries are actively involved in this research area, providing opportunities for future researchers.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
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)