Article
Physics, Fluids & Plasmas
Alexei Boulbitch, Alexander L. Korzhenevskii
Summary: This study investigates a crystal with a motionless crack, exhibiting a transformational process zone at the crack tip within the field-theoretical approach. The study demonstrates the extension of the zone beyond the crack tip due to zone boundary surface tension, leading to crack-tip shielding and the formation of transformation toughness. The research provides an accurate analytical approximation for the transformation toughness based on experimentally accessible parameters of the phase diagram.
Article
Construction & Building Technology
Yaowen Xu, Chaojun Wan, Xuhui Liang, Hongyu Yang
Summary: This paper investigates the reinforcement effects of different fibers on alkali-activated slag (AAS) material. It demonstrates that strain-hardening and clinker-free composites can be achieved using a combination of PVA, PE, and steel fibers. The study finds that different fibers have various reinforcement effects on the matrix and points out the poor adaptability of PVA and PE fibers in high alkalinity AAS material. Furthermore, a new relationship between crack numbers and strain-stress curves is established to characterize the strain-hardening property of fiber-reinforced composites.
CASE STUDIES IN CONSTRUCTION MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Qiang Li, Sheng Huang, Yakai Zhao, Yimin Gao, Upadrasta Ramamurty
Summary: In titanium matrix composites (TMCs), the addition of ceramic reinforcements enhances strength and specific stiffness but lowers ductility and fracture toughness due to the location of the reinforcement particles at the grain boundaries. This study demonstrates that simultaneously enhancing strength, ductility, and fracture initiation toughness (KQ) is possible if the particles are micron sized and predominantly present within the grains. The microstructural design of TMCs, especially the location of reinforcements with respect to grain boundaries, plays a crucial role in determining the overall mechanical performance.
Article
Chemistry, Physical
Diogo M. Neto, Micael F. Borges, Edmundo R. Sergio, Fernando Antunes
Summary: This study numerically investigated the effect of thermal residual stresses (TRSs) on fatigue crack growth (FCG), revealing that compressive stresses delay FCG while tensile stresses accelerate it. The research also found that TRSs only affect FCG by changing the crack closure level.
Article
Materials Science, Multidisciplinary
Jiamin Sun, Klaus Dilger
Summary: A study on the accurate prediction of welding residual stresses (WRS) in ultra-high strength steel S960 weldments found that the amount of strain hardening for S960 steel is low at room and high temperatures, but non-ignorable at medium temperatures. The applied material plasticity model had almost no influence on the computed longitudinal residual stress, but could slightly affect the predicted magnitude of transverse residual stress. The use of a perfect-plastic (non-hardening) model is recommended for accurately predicting WRS in numerical simulation of S960 steel.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Mechanics
Panagiotis A. Danoglidis, Emmanuel E. Gdoutos, Maria S. Konsta-Gdoutos
Summary: This study reports recent developments in hybrid reinforced cementitious composites using CNTs, CNFs, and PP microfibers, which significantly enhance load carrying capacity and energy absorption capability. Experimental results show increased modulus of elasticity, first crack strength, and toughness with the addition of CNTs and CNFs in PP-reinforced mortars. The hybrid mixes exhibit increased toughness, higher residual strength, and the ability to sustain higher loads while maintaining tensile load carrying capacity. The exceptional mechanical behavior is attributed to a synergistic interaction between nano and micro scale fiber reinforcement.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Materials Science, Multidisciplinary
Yue Ding, Wei-Ke Yuan, Xuan-Ming Liang, Gang-Feng Wang, Xinrui Niu
Summary: This work investigates spherical indentations on elastic-perfectly plastic materials and strain-hardening materials using finite-element method (FEM) simulations. A new method is proposed to extract the yield strength and strain-hardening exponent directly from spherical indentation. The deviation of nominal contact pressure from Hertzian prediction is used to determine the plastic parameters, and the difference between Hertzian contact pressure and real contact pressure is investigated for contact radius estimation. The validation of this method shows good agreement between analytical stress-strain relationships and FEM simulations.
ADVANCED ENGINEERING MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Lei Lei, Qiwei Zhu, Qinyang Zhao, Ming Yang, Wenxing Yang, Weidong Zeng, Yongqing Zhao
Summary: This study investigates the impact toughness and deformation mechanism of near-alpha-type low-temperature titanium alloy CT20 at different temperatures. It is found that CT20 exhibits high impact toughness at 20 degrees C, but brittle fracture occurs at -196 degrees C. The tortuous crack path, dislocation slip, and deformation twinning synergistically contribute to the high impact toughness at 20 degrees C, while the plastic deformation capacity decreases significantly at -196 degrees C.
MATERIALS CHARACTERIZATION
(2023)
Article
Materials Science, Multidisciplinary
Alexander J. Leide, Richard I. Todd, David E. J. Armstrong
Summary: This study investigates indentation deformation of silicon carbide after irradiation using HR-EBSD and Raman spectroscopy. The research reveals significant differences post-irradiation, with a wider range of plastic deformation in the indented region and fracture suppression due to swelling-induced compressive residual stresses.
Article
Engineering, Mechanical
Gyoko Oh, Yoshiaki Akiniwa
Summary: This study investigates the fatigue properties and influence factors of thin-walled corners in automobiles, machines, and structures, analyzing stress-strain behavior parameters, crack initiation stress amplitudes, residual stresses, etc. The research shows significant effects of strain amplitude ratios, work hardening effects, and corner specimen radius ratios on fatigue strength.
INTERNATIONAL JOURNAL OF FATIGUE
(2021)
Article
Mechanics
Tito Andriollo, Varvara Kouznetsova
Summary: The study reveals that the applicability of Irwin's estimate in metals with particles is questionable when the plastic zone size is comparable to the particle spacing. A new compact formula for plastic zone size is proposed in this scenario where the PZ shape differs from von Mises plasticity expectation.
ENGINEERING FRACTURE MECHANICS
(2021)
Article
Chemistry, Physical
Jacob Junior, Ashish Kumer Saha, Prabir Kumar Sarker, Alokesh Pramanik
Summary: The study examined the effects of mono and hybrid fibres on various properties of fly ash geopolymer mortar. It was found that steel fibres could increase compressive strength, while low-modulus fibres led to significant strength reduction. Multiple cracking and deflection hardening behaviors could be achieved in high sand to binder ratio fly ash geopolymer mortars by using steel fibres in mono or hybrid forms.
Article
Materials Science, Composites
Shi-Lang Xu, Hong-Lin Xu, Bo-Tao Huang, Qing-Hua Li, Ke-Quan Yu, Jiang-Tao Yu
Summary: In this study, ultrahigh-strength ultrahigh-toughness cementitious composites (UHS-UHTCC) with exceptional mechanical strength and crack resistance were developed. The use of micro-polyethylene and steel fibers effectively bridged cracks in UHS-UHTCC, making it an excellent material for civil infrastructure.
COMPOSITES COMMUNICATIONS
(2022)
Article
Construction & Building Technology
Soner Guler, Zehra Funda Akbulut
Summary: This study compares the changes in mass loss, relative dynamic modulus of elasticity (RDME), residual compressive strength (RCS), residual flexural strength (RFS), and residual flexural toughness (RFT) of 3D, 4D and 5D steel fiber-reinforced concrete (SFRC) specimens after freeze-thaw (F-T) cycles. The results show that steel fibers do not affect mass loss of concrete after F-T cycles, but SFRC samples have higher RDME, RCS, RFS, and RFT values than control concrete. Furthermore, 5D steel fibers are more effective in improving the residual strength and toughness capacity of concrete after F-T cycles due to their stronger fiber/matrix interface.
JOURNAL OF BUILDING ENGINEERING
(2022)
Article
Chemistry, Physical
Peter Donkor, Esther Obonyo, Christopher Ferraro
Summary: Ongoing research efforts focusing on improving the flexural performance of compressed earth blocks (CEB) using polypropylene (PP) fibers have shown promising results, with specimens exhibiting improved ductility when fiber content exceeded 0.6%. A predictive model for equivalent flexural strength has been proposed based on the findings of this study.
Article
Environmental Sciences
Javed Mallick, Swapan Talukdar, Majed Alsubih, Mohd. Ahmed, Abu Reza Md Towfiqul Islam, Shahfahad, Nguyen Viet Thanh
Summary: This study developed and validated a novel artificial intelligence model for delineating GWP zones, which is a coupling of five ensemble benchmark algorithms with particle swarm optimization. Nine parameters were used for modeling and a ROC-based sensitivity analysis was proposed. The hybrid PSO-RF model outperformed other proposed models.
GEOCARTO INTERNATIONAL
(2022)
Article
Environmental Sciences
Nadeem A. Khan, Awais Bokhari, Muhammad Mubashir, Jiri Jaromir Klemes, Rachida El Morabet, Roohul Abad Khan, Majed Alsubih, Mudassar Azam, Sidra Saqib, Ahmad Mukhtar, Apurav Koyande, Pau Loke Show
Summary: The study demonstrated that the series-connected SAFF reactor and tubesettler have high removal efficiency for hospital wastewater treatment, although nitrate concentration may increase. SAFF and tubesettler each have advantages in removing COD, BOD5, and phosphate, but may fall short in nitrate removal. Nitrification reactions indicate good aeration in the system, but an anaerobic unit is still needed for complete denitrification.
Article
Environmental Sciences
Javed Mallick, Swapan Talukdar, Mohammed K. Almesfer, Majed Alsubih, Mohd Ahmed, Abu Reza Md Towfiqul Islam
Summary: Identifying homogeneous rainfall zones in Saudi Arabia is crucial for water resource and agriculture management. This study utilized various trend analysis techniques on 40-year rainfall records to identify three distinct clusters with different rainfall trends. The results will contribute to future work on climatic zone identification and water resource management strategies.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Environmental Sciences
Khaled Mohamed Khedher, Zaher Munther Yaseen, Mofareh D. Qoradi, Mohamed Hechmi El Ouni, Nabil Ben Kahla, Saeed Alqadhi, Majed AlSubih, Essaied Laatar, Samah Elbarbary, Mohamed Abdel Zaher
Summary: In this research, the risk of rock instability in a road section in Saudi Arabia was evaluated using satellite images and geographic information systems. Field investigations and testing were conducted to characterize the geological structure and environmental components of the road section. Simulations, rankings, and calculations were used to map the vulnerability and risk of rock slope instability, providing a scientific basis for urban planning in the region of study.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Multidisciplinary Sciences
Roohul Abad Khan, Rachida El Morabet, Nadeem A. Khan, Sirajuddin Ahmed, Majed Alsubih, Nabisab Mujawar Mubarak, Mohammad Hadi Dehghani, Rama Rao Karri, Nooshin Zomorodiyan
Summary: The treatment and disposal of wastewater containing pharmaceuticals and drug residues are challenging. This study investigated the performance of an electro bioreactor and tubesettler in treating hospital wastewater, focusing on the removal of chemical oxygen demand, nitrate, and phosphate. The results showed that the electro bioreactor effectively reduced the chemical oxygen demand and phosphate concentrations, while the tubesettler reduced the chemical oxygen demand concentration.
SCIENTIFIC REPORTS
(2022)
Article
Environmental Sciences
Majed Alsubih, Javed Mallick, Abu Reza Md. Towfiqul Islam, Mohammed K. Almesfer, Nabil Ben Kahla, Swapan Talukdar, Mohd. Ahmed
Summary: This study evaluates the surface water quality at a dam in the Asir region of Saudi Arabia and examines the effects of physicochemical parameters and trace metals on irrigation. The results show that the dam water is mostly suitable for irrigation, except for certain parameters. The study suggests the need for proper protective measures to reduce the potential impact of physicochemical parameters and metals on irrigation water in agricultural fields.
Article
Ecology
Javed Mallick, Majed Alsubih, Mohd. Ahmed, Mohammed K. Almesfer, Nabil Ben Kahla
Summary: This study investigates the impact of rapid urban land use and land cover changes on the environment, using the twin city of Abha-Khamis Mushyet in Saudi Arabia as a case study. Through statistical and spatial analysis, the study finds a correlation between land surface temperature (LST) and urban biophysical parameters, with a positive relationship between normalized difference built-up index (NDBI) and temperature, and a negative relationship between normalized difference vegetation index (NDVI) and normalized difference water index (NDWI) with temperature. This study is important for policy makers in mitigating the effects of urban heat islands caused by land use and land cover changes.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2022)
Article
Ecology
Javed Mallick, Mohammed K. Almesfer, Majed Alsubih, Mohd Ahmed, Nabil Ben Kahla
Summary: Urbanization and land-use change have significant impacts on cumulative greenhouse gas emissions, and accurate assessments of city-level carbon storage and sequestration are necessary. This study in Abha, Saudi Arabia used the InVEST model to estimate carbon storage and sequestration capabilities under different land use categories.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2022)
Article
Environmental Sciences
Javed Mallick, Mohammed K. Almesfer, Majed Alsubih, Swapan Talukdar, Mohd Ahmed, Nabil Ben Kahla
Summary: This study proposes a new groundwater potentiality model (GPM) in the Bisha watershed, Saudi Arabia, by integrating LR-weighted and fuzzy logic-based EML models for present and future scenarios. The bagging hybrid model outperformed other models in predicting GPMs, and the results showed the distribution of different groundwater potential zones.
GEOCARTO INTERNATIONAL
(2022)
Article
Environmental Sciences
Roohul Abad Khan, Nadeem A. Khan, Rachida El Morabet, Majed Alsubih, Abdul Qadir, Awais Bokhari, Muhammad Mubashir, Saira Asif, Wai Yan Cheah, Sivakumar Manickam, Jiri Jaromir Klemes, Kuan Shiong Khoo
Summary: Groundwater, the second largest water source for daily consumption, has been extensively investigated for pollution levels in urban areas. This study focused on groundwater quality assessments in industrial areas, showing an increase in pollution levels from 2015 to 2018 with high non-carcinogenic and carcinogenic risks identified.
Article
Environmental Sciences
Roohul Abad Khan, Nadeem A. Khan, Rachida El Morabet, Majed Alsubih, Amadur Rahman Khan, Saimah Khan, Muhammad Mubashir, Deepanraj Balakrishnan, Kuan Shiong Khoo
Summary: Pharmaceutical compounds in hospital wastewater can be effectively removed using constructed wetland combined with tubesettler and aeration, reducing ecological risk.
ENVIRONMENTAL RESEARCH
(2023)
Article
Environmental Sciences
Mondher Tarchi, Noureddine Zaaboub, Majed Alsubih, Bochra Brik, Maria Virginia Alves Martins, Lotfi Aleya, Lamia Trabelsi
Summary: This study investigated the toxicity potential of the microalgal community that developed on LD-PE plastic debris in two regions of Monastir Bay, Tunisia. The concentrations of potentially toxic elements (PTEs) in sediments and plastisphere were compared to determine their toxicity to biological life. The plastispheres were composed mainly of cyanobacteria, chlorophytes, and diatoms, with the coastal zone showing a higher abundance of potentially harmful cyanobacteria. The plastisphere accumulated higher concentrations of PTEs compared to sediments, especially near harbors and industrial zones with human interference.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2023)
Article
Environmental Sciences
Haifa Ben Mna, Majed Alsubih, Mohamed Amine Helali, Walid Oueslati, Ayed Added, Lotfi Aleya
Summary: This study assesses the ecological risk of metal contamination in Bizerte Lagoon and investigates the effects of diagenetic processes on metal distribution and diffusion. The results reveal high risk to benthic organisms, particularly from Cd, Pb, and Ni. Dissolved metals in pore water also pose an ecological risk, although it is relatively low.
MARINE POLLUTION BULLETIN
(2022)
Article
Chemistry, Multidisciplinary
Majed Alsubih, Rachida El Morabet, Roohul Abad Khan, Nadeem A. Khan, Amadur Rahman Khan, Saimah Khan, Nazneen Mushtaque, Arshad Hussain, Mahmood Yousefi
Summary: Constructed wetland utilizes vegetation as a natural medium to remove pollutants from wastewater. This study evaluates the performance of constructed wetland in different seasons and assesses the removal efficiency and environmental risk of pharmaceutical compounds. The results show that the seasonal variation and dilution effect influence the removal of these compounds, and further research is needed to understand the removal mechanisms in different climatic conditions.
ARABIAN JOURNAL OF CHEMISTRY
(2022)
Article
Engineering, Multidisciplinary
Sivakumar Anandan, Majed Alsubih
Summary: The main objective of this study was to investigate the potential improvements in fracture properties of concrete by adding two different types of fibres (steel-brass hybrid fibres). Various concrete mixtures containing different proportions of steel and brass fibres were prepared and tested. The results showed that the hybrid fibre combinations had significant crack arresting properties and increased mechanical strength, with steel fibres providing post crack resistance and shorter brass fibres delaying crack origination. The hybrid fibre concretes exhibited a consistent increase in ultimate stress capacity and fracture strength.
JOURNAL OF ENGINEERING RESEARCH
(2023)
