Article
Construction & Building Technology
Shizhe Zhang, Zhenming Li, Bahman Ghiassi, Suhong Yin, Guang Ye
Summary: This study comprehensively investigated the fracture properties of hardened alkali-activated slag/fly ash pastes, revealing that the fracture properties are mainly determined by the Ca/Si ratio of C-(N-)A-S-H gel and capillary porosity. Contradictions between the Ca/Si ratios and intrinsic mechanical properties suggest a cohesion/adhesion-based mechanism dominantly affecting the fracture properties.
CEMENT AND CONCRETE RESEARCH
(2021)
Article
Construction & Building Technology
Shizhe Zhang, Shan He, Bahman Ghiassi, Klaas van Breugel, Guang Ye
Summary: This paper presents an experimental study on the interface bonding properties of PVA fiber in AASF pastes and reveals the influence of PVA fiber on the surrounding matrix. The research findings indicate that the chemical composition and structure of the fiber-matrix contact area play an important role in the interface bonding properties.
CEMENT AND CONCRETE RESEARCH
(2023)
Article
Construction & Building Technology
Tao Liu, Qingliang Yu, H. J. H. Brouwers, Xiaochun Fan
Summary: This study investigates the chloride diffusion behavior of alkali activated slag and fly ash blends with different contents of waste glass powder addition. The results show that increasing the content of waste glass powder enhances the chloride resistance of the blends.
JOURNAL OF SUSTAINABLE CEMENT-BASED MATERIALS
(2023)
Article
Construction & Building Technology
Wei Wang, Takafumi Noguchi, Ippei Maruyama
Summary: The ASR behavior of AAS/AAFA mortars was investigated and compared with OPC mortars, revealing that ASR-induced expansion in AAS mortar bars occurred earlier than in OPC mortar bars due to the early participation of reactive silica from aggregates in alkali-activation. The Ca/Si ratio of amorphous ASR products in AAS mortars was lower, while Al/Si and Na/K ratios were higher than that of OPC mortars.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Construction & Building Technology
Zhuangfei Su, Ze Liu, Huangqi Wang, Shicheng Xu, Dongmin Wang, Fenglan Han
Summary: This study investigates the reaction kinetics, microstructure, and phase evolution of alkali-activated Si-Mn slag (SiMnS) as a precursor. The results show that alkali-activated SiMnS exhibits two main exothermic processes, the generation of Si-rich gel and Al-rich gel. The alkalinity and the existence form of the alkaline activator determine the intensity and characteristics of the alkali activation reaction. SiMnS can be used as an alternative raw material in alkali-activated applications.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Construction & Building Technology
Hongqiang Ma, Congcong Fu, Kang Huang, Enyang Dai, Shaochen Zhang, Youliang Fang, Jingjing Feng
Summary: This paper explores the effect of cenosphere, a coal-based solid waste material with similar chemical compositions to fly ash, on the hydration kinetics and drying shrinkage characteristics of AAFS pastes, and reveals its action mechanism. The results show that the presence of cenosphere prolongs the hydration induction period, reduces the hydration exothermic rate or delays its peak value during the acceleration period, and increases the 72-hour hydration degree of the sample. Incorporating more than 20% cenosphere significantly reduces the drying shrinkage of AAFS pastes. The most suitable content of cenosphere is found to be 20% based on the comparison of compressive strength, drying shrinkage, and pore structure results. The action mechanisms of cenosphere include filling effect, pozzolanic activity, and surface effect. The addition of cenosphere decreases the amount of C-S-H, C-A-S-H, and N-A-S-H gel phases, but increases the formation of silicates (calcium hydrosilicates and calcium hydroaluminates).
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Review
Construction & Building Technology
Beibei Sun, Guang Ye, Geert de Schutter
Summary: In this paper, the mechanical properties and reaction mechanisms of alkali-activated materials such as blast furnace slag (BFS-AAM), fly ash (FA-AAM), and the combination of BFS and FA (BFS/FA-AAM) are reviewed. The factors influencing the strength of these materials and the control factors are summarized. The study reveals that ion concentrations determined by the control factors play a decisive role in strength development.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Construction & Building Technology
Kala Kondepudi, Kolluru V. L. Subramaniam
Summary: The study focuses on enhancing the buildability of printable alkali-activated mixtures by modifying the baseline mixture with alkaline activating solution and components like CMC, influencing the viscosity and properties of the mixture for achieving constructability in 3D concrete printing.
CEMENT & CONCRETE COMPOSITES
(2021)
Article
Materials Science, Ceramics
Jie Ren, Hongfang Sun, Qun Li, Zhenming Li, Xiaogang Zhang, Yanshuai Wang, Linfei Li, Feng Xing
Summary: This research studied the effects of natural seawater on the properties of alkali-activated slag/fly ash. The results showed that the use of seawater prolonged the setting time and reduced heat release, but had no significant impact on flowability. The mechanical properties of AASF were affected by the use of seawater, leading to the formation of new products. Additionally, the dissolution of fly ash particles was significantly delayed with the incorporation of seawater.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2022)
Article
Construction & Building Technology
Siyu Duan, Hao Wu, Ke Zhang, Hongqiang Liao, Zhibin Ma, Fangqin Cheng
Summary: This paper investigated the reaction kinetics of the steel slag-fly ash-desulfurized gypsum (SS-FA-DG) composite system by evaluating the influence of curing temperature on the formation of hydration products and the development of mechanical properties. The results indicated that the SS-FA-DG composite system developed through a five-stage process, and the compressive strength was largely influenced by the development of the hydration reaction and the curing temperature.
JOURNAL OF BUILDING ENGINEERING
(2022)
Article
Construction & Building Technology
Jian Zhang, Caijun Shi, Zuhua Zhang, Xiang Hu
Summary: This study elucidated the effects of slag/fly ash ratios, Na2O concentration, and silicate modulus on the reaction mechanism of sulfate attack on alkali-activated slag/fly ash cements using XRD, FTIR, and TG/DTG analysis. The results showed that MgSO4 attack on AACs was severe due to alkali dissolution and Mg2+ intrusion, whereas Na2SO4 attack did not significantly alter the C-A-S-H gel structures of AACs. Additionally, the resistance of NaOH-activated slag to MgSO4 was higher compared to Na2SiO3-activated slag, but this trend reversed with an 80% fly ash replacement level.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Bradut Alexandru Ionescu, Alexandra-Marina Barbu, Adrian-Victor Lazarescu, Simona Rada, Timea Gabor, Carmen Florean
Summary: It is now widely known that industrial by-products rich in silicon and aluminum can be transformed into green concrete, a sustainable material in construction, through alkaline activation. This study examined the effect of using fly ash and either marble dust or blast furnace slag on the performance of geopolymer materials. Physico-mechanical methods, FTIR spectroscopy, and microscopy were used to characterize the geopolymer materials. The results showed a reduction in mechanical strength performance when fly ash was substituted as the raw material.
Article
Construction & Building Technology
Zhenming Li, Xuhui Liang, Yun Chen, Guang Ye
Summary: The addition of metakaolin can significantly reduce the autogenous shrinkage of alkali-activated slag-fly ash paste, lower the compressive and flexural strength of the paste.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Construction & Building Technology
Richard Caron, Ravi A. Patel, Frank Dehn
Summary: A new model for reaction kinetics of waterglass-activated slag cements has been proposed, which successfully describes the different mechanisms during alkali-activation of slag with waterglass. The model has been tested against experimental and literature data, showing good fit and correlation with mix characteristics. The study provides insights into the factors influencing the kinetics of the process.
CONSTRUCTION AND BUILDING MATERIALS
(2022)
Article
Construction & Building Technology
Siva Uppalapati, Lucie Vandewalle, Ozlem Cizer
Summary: This study investigates the effect of sodium carbonate and sodium sulfate on the setting process of sodium silicate-activated slag-fly ash cements. The results show that the partial substitution of activators has no noticeable effect on the initial setting time, but significantly increases the final setting time. The condensation reaction between aluminosilicate units near the particle surface is likely responsible for setting, and a specific ultrasonic velocity range can be used to estimate the setting times of the studied cements.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Materials Science, Ceramics
Dale P. Prentice, Lauren Gomez-Zamorano, Magdalena Balonis, Bartu Erdemli, Kirk Ellison, Narayanan Neithalath, Dante Simonetti, Gaurav Sant
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2020)
Article
Construction & Building Technology
Sooraj A. O. Nair, Subhashree Panda, Manu Santhanam, Gaurav Sant, Narayanan Neithalath
CEMENT & CONCRETE COMPOSITES
(2020)
Article
Chemistry, Multidisciplinary
Sharu Bhagavathi Kandy, Iman Mehdipour, Narayanan Neithalath, Mathieu Bauchy, Edward Garboczi, Samanvaya Srivastava, Torben Gaedt, Gaurav Sant
Article
Construction & Building Technology
Naman Saklani, Gaurav Banwat, Benjamin Spencer, Subramaniam Rajan, Gaurav Sant, Narayanan Neithalath
Summary: This study presents a 3D mesoscale simulation approach that considers the effects of temperature, moisture content, and high neutron fluence on damage prediction in concrete irradiated in a test reactor. The simulation framework involves hygro-thermal analysis and radiation-induced volumetric expansion, providing a predictive tool for quantifying damage in concrete due to neutron irradiation under different conditions.
CEMENT AND CONCRETE RESEARCH
(2021)
Article
Materials Science, Multidisciplinary
Emily Ford, Kailasnath Maneparambil, Subramaniam Rajan, Narayanan Neithalath
Summary: This study investigates the use of supervised machine learning to predict the mechanical properties of a family of two-phase materials based on microstructural images, successfully demonstrating the accuracy of ML methods in predicting homogenized elastic properties and identifying key points related to microstructural features.
COMPUTATIONAL MATERIALS SCIENCE
(2021)
Editorial Material
Construction & Building Technology
Narayanan Neithalath
JOURNAL OF MATERIALS IN CIVIL ENGINEERING
(2021)
Article
Construction & Building Technology
Sooraj A. O. Nair, Avinaya Tripathi, Narayanan Neithalath
Summary: This study focuses on the effects of layer height parameters on the flexural strength and fracture properties of 3D printed concrete beams. The research shows that smaller layer heights are beneficial for both reinforced and unreinforced 3D printed concrete, although they result in more interfaces and longer printing times.
CEMENT & CONCRETE COMPOSITES
(2021)
Article
Engineering, Manufacturing
Sooraj A. O. Nair, Gaurav Sant, Narayanan Neithalath
Summary: This paper presents a suite of point cloud comparison techniques for 3D printing of cement-based materials, which can be used to quantify the mismatch between the designed and printed systems. It also proposes a print accuracy index and a topological set theory-based approach to evaluate the print quality.
ADDITIVE MANUFACTURING
(2022)
Article
Construction & Building Technology
Avinaya Tripathi, Sooraj A. O. Nair, Narayanan Neithalath
Summary: This study evaluates the buildability of 3D printed concrete through a novel approach, using modified compression tests and models to predict failure heights, which enhances control in material design and printing process.
CEMENT & CONCRETE COMPOSITES
(2022)
Article
Materials Science, Ceramics
Taihao Han, Jie Huang, Gaurav Sant, Narayanan Neithalath, Aditya Kumar
Summary: This study uses machine learning models to predict the mechanical properties of ultrahigh temperature ceramics and develops a simplified prediction model based on the ranking of input variables. The results show that data-driven numerical models can accelerate the development of ultrahigh temperature ceramics.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2022)
Article
Engineering, Manufacturing
Sahil Surehali, Avinaya Tripathi, Atharwa Samir Nimbalkar, Narayanan Neithalath
Summary: Layered concrete systems obtained using 3D printing show defects in layer and filament interfaces, affecting the transport of moisture and ionic species and impacting durability. This study investigates the influence of layer heights and transport directions on the non-steady state chloride migration coefficients of 3D printed concretes. The direction-dependent coefficients are found to be 10-30% higher than those of cast samples, with the inter-filament interfaces being more detrimental. The findings provide guidance on choosing printing directions with respect to ionic ingress.
ADDITIVE MANUFACTURING
(2023)
Article
Construction & Building Technology
Taihao Han, Jie Huang, Gaurav Sant, Narayanan Neithalath, Ashutosh Goel, Aditya Kumar
Summary: This study develops an advanced model that utilizes artificial intelligence to accurately predict the hydration kinetics of [PC + SCM] binders, achieving high reliability.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Chemistry, Physical
Sahil Surehali, Avinaya Tripathi, Narayanan Neithalath
Summary: This paper analyzes the effect of print layer heights and loading direction on the compressive response of plain and fiber-reinforced 3D printed concrete. The study shows that fiber reinforcement can reduce the lower strength of 3D printed specimens when compared to cast specimens. Digital image correlation is used to acquire strain profiles and characterize the directional dependence of peak stress and strain. Orienting weaker interfaces appropriately or strengthening them through material modifications enables attainment of near-isotropy in 3D printed concrete elements.
Article
Geochemistry & Geophysics
Taihao Han, Bryan K. Aylas-Paredes, Jie Huang, Ashutosh Goel, Narayanan Neithalath, Aditya Kumar
Summary: This study explores the prediction of compressive strength in limestone calcined clay cement (LC3) using a machine learning model. Three feature reduction methods are employed to analyze the impact of LC3 components and mixture design on compressive strength. Practical guidelines for applying these methods on cementitious materials are provided, and a feature enhancement method is utilized to improve prediction accuracy.
Article
Chemistry, Multidisciplinary
Sara Vallejo Castano, Erika Callagon La Plante, Sho Shimoda, Bu Wang, Narayanan Neithalath, Gaurav Sant, Laurent Pilon
Summary: The study demonstrates a novel process to precipitate calcium hydroxide at sub-boiling temperatures from industrial waste, significantly reducing CO2 emissions compared to traditional methods.
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)
