Digital Commons Network^™

Computational Modelling Of 3d Mesostructure Of Recycled Aggregate Concrete, Yi Ding, Gert Van Der Heijden, Mingzhong Zhang

International Conference on Durability of Concrete Structures

Recycled aggregate concrete (RAC) has a complex mesostructure with heterogeneous compositions of aggregates, interfacial transition zones (ITZs), and mortar. It is still a big challenge to simulate the 3D mesostructure of RAC accounting for its inherent characteristics, which plays a crucial role in its mechanical properties and long-term durability. This study introduces an advanced computational framework based on Voronoi tessellation approach to generate the highly realistic 3D mesostructured of RAC. The proposed framework can address the key challenges in simulating irregular aggregate morphology and spatial distribution while effectively incorporating the multi-phase structure of RAC which consists of old and new …

Evaluation Of Ionic Behaviours Under Electric Field With Integrated Chemo-Electric Numerical Platform, Kai Matsutani, Zhao Wang, Yuya Takahashi, Tetsuya Ishida

International Conference on Durability of Concrete Structures

Chloride ion plays a critical role in terms of steel corrosion for reinforced concrete structures, which leads to structural degradation. To investigate the macro-cell corrosion and mechanical deterioration, an integrated chemo-electric numerical platform has been developed with spatial-averaged modelling of steel and concrete. The verification of macro-cell circuit in structural concrete induced by applied charge has been achieved, while the ionic behaviors under impressed charge evaluated by this platform remains unverified. This study numerically investigates the ionic behavior of chloride under both ponding and electrophoresis conditions with the integrated platform. Comparison between numerical simulation and available experimental data shows the …

Exploring Aerial Additive Manufacturing With Cementitious Materials Using Autonomous Drones, Richard James Ball, Barrie Dams, Paul Shepherd, Binling Chen

International Conference on Durability of Concrete Structures

Aerial additive manufacturing (AAM) represents a novel approach to construction by enabling untethered autonomous unmanned aerial vehicles (UAVs, or drones) to deposit cementitious materials in mid-flight, overcoming geometric and accessibility limitations associated with ground-based additive manufacturing. This study presents research to investigate the structural viability of cementitious mixes tailored for aerial extrusion, focusing on rheological optimisation, mechanical performance, and deposition feasibility. Pseudoplastic behaviour was achieved through the use of hydrocolloids, enabling low viscosity under shear for extrusion while rapidly stiffening post-deposition to maintain layer geometry. Fibre reinforcement and inorganic fullerene tungsten disulphide (IF-WS₂) nanoparticles were incorporated to enhance flexural strength, …

Deploying 3d Concrete Printing For Large-Scale Building Construction In Saudi Arabia: A Case Study, Zakiah Yousif Altehaini, Mohammed Ahmad Dayili, Meshari Ali Alrajab, Adel Nasser Alharbi, Ali Khudhran Alutaibi, Eyad Hamzah Garatly

International Conference on Durability of Concrete Structures

This paper details the successful large-scale implementation of 3D concrete printing (3DCP) for the construction of large building in remote area of Saudi Arabia. As one of the first religious buildings in the region constructed using additive manufacturing, this project showcases 3DCP's technological and environmental potential for contemporary building. In order to ensure sustainability and cost effectiveness, the mosque was constructed using a COBOD BOD2 gantry printer and a customised concrete mix made up of 99% locally sourced materials and 1% CEMEX D-fab admixture. To maximise thermal insulation and accommodate mechanical, electrical, and plumbing (MEP) systems, the structure included a …

Microstructure Characterisation Of Alkali-Activated Fly Ash-Slag Paste At Elevated Temperatures, Wenlin Tu, Mingzhong Zhang

International Conference on Durability of Concrete Structures

Alkali-activated fly ash-slag (AAFS) cured at ambient temperature has been considered as a promising eco-friendly alternative to traditional cement-based binders, offering reduced carbon emissions and enhanced durability. However, understanding how these materials respond to extreme conditions, particularly at high temperatures, remains a critical area of study. Therefore, it is essential to investigate this material for ensuring their reliability in fire-prone and high-temperature environments. This paper presents a systematic experimental study on microstructural and damage evolution in AAFS paste exposed to elevated temperatures (from 20 °C to 800 °C) in terms of changes in phase assemblage and pore structural characteristics as …

Static Compressive Behaviour Of A Novel Functionally Graded 3d Re-Entrant Lattice Reinforced High Performance Concrete, Yiwei Xuan, Mingzhong Zhang, Dianwei Gao

International Conference on Durability of Concrete Structures

This study systematically studies the static mechanical properties of high-performance concrete (HPC) reinforced with a 3D re-entrant lattice structure, considering the effect of functionally gradient design. The uniform 3D re-entrant lattice (U) and the corresponding vertically positively and negatively graded lattices (FG1 and FG2) were designed and manufactured with 3D printing. The plain HPC (P-HPC) and HPC reinforced with U (U-HPC), FG1 (G1-HPC) and FG2 (G2-HPC) were fabricated accordingly. Static compressive tests were then conducted to investigate the static compressive behaviour of 3D re-entrant lattice and corresponding lattice reinforced HPC. Results indicate that all 3D re-entrant structures exhibit clear NPR …

Impact Of Sulfate Activation Of Slag Cement On The Performance Of Coarse Recycled Aggregate Concrete, Md Ikramullah Khan, V Vinayaka Ram

International Conference on Durability of Concrete Structures

The global construction industry is facing increasing pressure to adopt sustainable practices, driving the search for alternatives to conventional concrete. This research investigates the development of eco-friendly concrete by replacing virgin coarse aggregates with recycling plant-based coarse recycled aggregates (CRAs) and utilising Portland slag cement (PSC). While PSC-CRA based concrete offers environmental advantages, it typically exhibits lower early-age strength and durability, limiting its practical application. To address these limitations, a systematic experimental study was conducted to evaluate the efficacy of sodium sulfate (Na2SO4) as a chemical activator to the binder. This research comprehensively assessed the impact of the activator on …

Recent Advances In Geopolymer Feedstocks Activation For Sustainable Cement Production, Oluyemi Kehinde, David J. Hughes, Emeka H. Amalu, Dali Bondar

International Conference on Durability of Concrete Structures

The growing environmental and safety issues posed by human activities have underlined the importance of Ordinary Portland Cement production, which is a major contributor to carbon dioxide emissions that impede Net Zero goals. The urgent need to produce cement substitutes with reduced carbon footprints has prompted research on geopolymers formed from industrial mineral wastes. These materials provide promising sustainable development solutions, but the selection of appropriate activation methods remains a significant constraint to their widespread industrial and economical application. A systematic review using the PRISMA protocol included 302 recent and relevant papers, identifying four principal activation strategies and their combinations …

Influence Of Printing Speed And Nozzle Size On Buildability Of 3d Printed Concrete Walls: A Nonlinear Finite Element Study, Auliagitta Kumala Apsari, Asdam Tambusay, Priyo Suprobo, Benny Suryanto

International Conference on Durability of Concrete Structures

The increasing adoption of additive manufacturing in construction necessitates robust simulation frameworks capable of capturing the time-dependent mechanical behaviour of fresh concrete. This study examines the influence of printing speed and nozzle size on the buildability of infilled concrete walls using finite element (FE) simulations. A nonlinear fracture-plastic constitutive model was employed to simulate the time-dependent mechanical behaviour of fresh concrete, with the modelling framework first validated against previously published experimental data to ensure reliability. Subsequently, six wall configurations were analysed, incorporating nozzle diameters of 30 mm and 40 mm, and printing speeds of 20, 30, and 40 mm/s. The …

Steel Fibre Reinforced Self-Compacting Geopolymer Concrete Structural Members, Jubilant Nyasha Chidziya, Chikako Fujiyama

International Conference on Durability of Concrete Structures

Geopolymer concrete (GPC) is an innovative and sustainable alternative to ordinary Portland cement concrete (OPC) for structures in seismic prone areas owing to tough and ductile performance due to strong bond with steel reinforcement. However, the application of GPC in construction projects is low due to limited understanding of the long-term performance of structural members. The objective of this study is to examine the effects of steel fibres on the flexural properties of self-compacting geopolymer concrete (SCGC) and OPC beams. The study involved investigation of the fresh and mechanical properties of concrete. Structural parameters such as toughness, and ductility index …

Surface Morphology, Bond Strength And Failure Behaviour Of Steel Vs Basalt Rebars In Alkali Activated Concrete, Ansu Mary Alex, Sreejith Nanukuttan, Adeline Mccartney, Marios Soutsos, Daniel Mcpolin

International Conference on Durability of Concrete Structures

This microscopic characteristics of basalt bars after exposure to alkaline solutions and pullout performance of steel and basalt rebars embedded in conventional and alkali-activated concrete were studied. The overarching goal is to assess the potential of basalt rebars as an alternative to conventional steel reinforcement in alkali activated concrete elements. To understand their durability in alkaline environments, especially within alkali-activated concrete (AAC), steel and basalt rebars were subjected to an accelerated exposure test in high-pH simulated concrete pore solutions, for 24hrs. This aimed to replicate the aggressive internal environment typically found in AAC and mixes with supplementary cementitious materials. Post-exposure …

Durability Performance Of 3d-Printed Ultra-High Strength Concrete Incorporating Corrosion Inhibitor, Jyotish Kumar Das, M. Mirza Abdillah Pratama, Behzad Nematollahi, Maurizio Guadagnini

International Conference on Durability of Concrete Structures

This paper reports preliminary results on the durability performance of a 3D-printed ultra-high strength concrete (3DP-UHSC). A nitrite-based compound was added at varying dosages (0%, 2%, and 4% by mass of binder) to the developed 3DP-UHSC as a corrosion inhibitor. The effects of the corrosion inhibitor on the workability of fresh mixes and the mechanical properties (compressive and flexural strengths in various directions) of the 3DP-UHSC mixes were studied. Furthermore, the durability performance of the 3DP-UHSC was assessed by conducting porosity, water absorption, and chloride permeability measurements. Mould-cast specimens were also prepared and tested for comparison purposes. The results indicated …

Comparative Assessment Of Battery And Hydrogen Energy Storage In A Grid-Connected Heat-Electricity Integrated Microgrid, Naglaa Elsherbiny, Mohamed Elgamal, Islam Ismael, Akram Elmitwally

Mansoura Engineering Journal

Given the significant challenges of conventional power systems, including high emissions and operational costs, transitioning to microgrids (MGs) is increasingly critical. This paper presents a comprehensive evaluation of three energy management strategies for a grid-connected, heat-electricity integrated MG: (i) a base case without storage, (ii) a battery-based energy storage system (B-BESS), and (iii) a hydrogenbased energy storage system (H-BESS) comprising an electrolyzer (ELC), hydrogen tank (HT), and fuel cell (FC). This study optimizes operational profit and emissions reduction by integrating renewable energy and heat recovery mechanisms. Simulation results show that, compared to the base case, both B-BESS and H-BESS significantly …

Synergistic Effects Of Orifice Geometry And Inclination Angle On The Damping Performance Of Tuned Liquid Column Vibration Absorbers, Mohamed M. Abou Elenin, Younes K. Younes, Mohamed F. Younes

Mansoura Engineering Journal

This study experimentally investigates the dynamic damping performance of passive tuned liquid column vibration absorbers (TLCVAs), focusing on the influence of vertical column inclination angle and orifice disc configuration. Free vibration tests were conducted on a primary system equipped with a TLCVA using a custom-designed test rig. The experimental framework systematically varied inclination angles from to and tested both single-hole and multi-perforated orifice discs, each designed with an equivalent total flow area. A MATLAB-based signal processing framework was employed to analyze time-domain responses, and the logarithmic decrement method was applied to determine the damping ratio of the primary system. The …

A Comprehensive Approach Addressing The Most Chronic And Emerging Contaminants Along The Egyptian Mediterranean Coast, Tarek O. Said

Blue Economy

Newly identified substances known as emerging contaminants (ECs) are harmful to the environment and public health, frequently because limited regulation and incomplete understanding of their impacts. They comprise a broad variety of materials, such as insecticides, industrial wastes, personal care items, and medications. Persistent pollutants (POPs) are organic compounds that have remained in the environment for an extended period of time. They tend to move through the atmosphere over enormous distances making them a chronic contaminant and may harm ecology and humanity over time. In Egypt, particularly within its Mediterranean Exclusive Economic Zone (EEZ), heavy metal (HM) contamination is increasingly …

Ozark Historical Review, V. 44, 2015

The Ozark Historical Review

No abstract provided.

Tableau Part Ii - October 2025, Rubab Shahzad

Day Family Research Lab Workshop Series

Part Two of Introduction to Tableau. Learn to make cool visualizations using Tableau. A hands-on opportunity where we will go over calculated fields, hierarchies, unions, dashboards, and stories.

Prior experience with Tableau is recommended

Incorporating An Innovative Kennel In A Guide Dog Program Based On The Health And Welfare Of Dogs And Humans, Naoko Koda, Miwa Murata, Sakura Mizuta

People and Animals: The International Journal of Research and Practice

During guide dog training, dogs live in kennels and lack house training. The demand for guide dogs that can live easily with their users who are visually impaired is increasing. The Kansai Guide Dogs for the Blind Association (KGBDA) in Japan built an innovative wooden kennel (Mokka Terrace) that is more similar to homes than general kennels and that efficiently controlled dogs and reviewed their operations. This study conducted a literature survey, participant observations, and semi-structured interviews with staff to clarify the background and consensus-building process involved in creating the Mokka Terrace, corresponding efforts, and its strengths, issues, and prospects. …

Editorial, Joseph P. Hupy, Mary M. Fink

Journal of Aviation Technology and Engineering

Editorial for JATE 13.2.

Editorial, Joseph P. Hupy, Mary M. Fink

Journal of Aviation Technology and Engineering

Editorial for JATE 13.1.

J Am Coll Dent 2018 85 1

Journal of the American College of Dentists

The Journal of the American College of Dentists (JACD) publishes scholarly articles, editorials, essays, and reflections addressing the ethical, professional, and social dimensions of dentistry. The Journal serves as a forum for advancing ethics, professionalism, leadership, and excellence within the dental community. By fostering dialogue across disciplines and perspectives, JACD provides readers with insights that encourage ethical, professional practice, lifelong learning, and service to the public, reinforcing dentistry’s commitment to advancing oral healthcare and the common good.

Species Snapshot: Greater Roadrunner (Geococcyx Californianus), Steven Gabrey

North American Bird Bander

No abstract provided.

2024 American Field Ornithologist (Afo) And Western Bird Banding Association (Wbba) Joint Annual Meeting Scientific Abstracts, Walter H. Sakai

North American Bird Bander

No abstract provided.

Western Bird Banding Association Grant Announcement And 2024 Grant Award, Walter H. Sakai

North American Bird Bander

No abstract provided.

Ibba Conference Set For 24-26 October 2025 At Carpenter St. Croix Valley Nature Center, Mn, Peter Lowther

North American Bird Bander

No abstract provided.

Inland Flyway Review Maps 2024 Report, Steven Gabrey

North American Bird Bander

No abstract provided.

Save The Date! March 20-22, 2026 Eastern Bird Banding Association Conference And Meeting, Annie Lindsay

North American Bird Bander

No abstract provided.

Message From The President, Aaron Given

North American Bird Bander

No abstract provided.

2025 Annual Membership Meeting Of The Eastern Bird Banding Association, Maren Gimpel

North American Bird Bander

No abstract provided.

Sedge Wren Recaptures And A Longevity Record, David A. Cimprich

North American Bird Bander

No abstract provided.