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Shear And Compressive Joint Behaviour Of Concrete Floating Structure For Offshore Wind Turbine, Maryam Imran, Satoshi Komatsu, Risa Yamada, Toyofumi Matsuo

International Conference on Durability of Concrete Structures

Japan's commitment to growing renewable energy generation from 30 to 45 GW has intensified the focus on offshore wind turbines. Due to the presence of extensive deep-sea waters, the installation of fixed turbines is impractical, making floating structures a more viable option. For supporting structure of said turbines, concrete is preferred over steel as it offers various commercial and technical benefits. However, the response of concrete in offshore environment is still under consideration. When considering rationalisation of construction, pre-casting of modules is one option, however in that case, it is necessary to clarify the behaviour of the joints. This research …

Investigation Of Corrosion Resistance Of Fly Ash Self-Compacting Mortar, Md Marghoobul Haque, Supratic Gupta

International Conference on Durability of Concrete Structures

One of the leading reasons for failure of structural members is corrosion of reinforcement. Structures corresponding to the marine environment like ports, harbours and bridges are more susceptible towards the risk of corrosion. Chlorides are one of the main reasons for the initiation of corrosion which can penetrate from various sources like the marine atmospheric environment or the use of deicing salts in the colder regions. Corrosion is a long-term process, so, in this research, an accelerated corrosion testing of self-compacting mortar has been performed to understand the behaviour of addition of fly ash in the mortar mixes against the …

Application Of Cnt/Cf Cement Composite Sensor For Corrosion Monitoring In Chloride-Exposed Reinforced Concrete, Michael Tesfaye Emiru, Kim Hyeongki

International Conference on Durability of Concrete Structures

This study investigates the use of a conductive cement composite containing carbon nanotubes (CNTs) and carbon fibres (CFs) as a reference electrode for corrosion monitoring in reinforced concrete. For comparison, stainless-steel reference electrodes were also prepared. Both CNT/CF cement composite and stainless-steel electrodes were immersed in a 10% NaCl solution for three months to simulate a chloride-rich marine environment. The open circuit potential (OCP) of both reference electrodes was measured against a standard silver/silver chloride electrode (SSCE) over time. Two reinforced mortar samples and one reinforced concrete sample were tested under different exposure conditions. In Experimental Program 1, a mixed-in …

Utilisation Of Semi-Naturally Carbonated Steelmaking Slag As Concrete Aggregate, Sumire Nakamura, Yuichiro Kawabata

International Conference on Durability of Concrete Structures

Steelmaking slag has emerged as a promising material for low-carbon concrete, owing to its ability to sequester CO₂ through carbonation. However, CO2 sequestration by steelmaking slag and its utilisation is still far from practical application due to the high energy consumption and cost of the accelerated carbonation process. Anticipating that optimising the pre-natural carbonation during storage would reduce the energy and cost for accelerated carbonation, this study focused on the natural carbonation potential of steelmaking slag. In addition, the applicability of naturally carbonated steelmaking slag as aggregate for concrete was investigated. The long-term exposure experiment simulating outdoor storage demonstrated that …

The Effect Of Cracks On The Corrosion Distribution Along Rebar In A Chloride Contaminated Concrete, Shogo Kiriyama, Koichi Kobayashi

International Conference on Durability of Concrete Structures

Cracks in concrete allows the ingress of corrosive factors such as chloride ions, water, and oxygen, and reduce the durability of the structure. Therefore, the generation and the development of the cracks must be controlled within the extent with which they do not affect the durability. However, the influences of crack on the steel bar corrosion are still poorly understood. Therefore, in order to investigate how the ingress of corrosion factors through cracks affects rebar corrosion and corrosion distribution, accelerated deterioration tests simulating a chloride rich environment were conducted in this study, using bending crack width and corrosion acceleration period …

Deterioration Prediction And Optimal Repair Timing Assessment For Rc Abutments In Tidal River Environments, Yuto Suzuki, Nobuhiro Chijiwa, Kazuhide Nakayama, Mitsuyasu Iwanami, Amadou Sakhir Syll

International Conference on Durability of Concrete Structures

Reinforced concrete (RC) abutments constructed in tidal rivers are periodically exposed to saltwater due to tidal fluctuations, which can lead to rebar corrosion and a decline in structural performance. To maintain such infrastructure more efficiently and cost-effectively, high-resolution simulations in both time and space can help predict the timing of performance degradation with greater accuracy, enabling optimal repair and reinforcement scheduling. Achieving higher accuracy in these simulations requires appropriate modelling of continuous environmental variations, such as tidal fluctuations, temperature, and humidity. This study focuses on RC abutments located in tidal zones and examines a modelling approach to represent environmental conditions …

Simulation Analysis Of Secondary Creep Of Corrosion Damaged Reinforced Concrete Beams Based On Abaqus, Hao Guo, Wenbin Liu, Yixue Zhang, Weiliang Jin

International Conference on Durability of Concrete Structures

Concrete creep is defined as deformation over time under a sustained load. When a structure is subjected to additional actions such as corrosion, damage to its components can occur, leading to a deterioration in performance. The structure then develops a long-term deformation known as secondary creep, which is greater than the creep deformation that occurs under sustained loads alone. The problem of secondary creep caused by corrosion of reinforcing steel, which is a common durability issue, is still not well understood. Corrosion-induced degradation, including partial loss of reinforcement, bond degradation and concrete cracking, exacerbates creep deformation by altering stress distribution …

3d Rbsm Conduit Model For Simulating Moisture Transport In Compressively Damaged Concrete, Dawei Ren, Kohei Nagai

International Conference on Durability of Concrete Structures

This study investigates the simulation of moisture transport in concrete under compressive damage using the 3D RBSM Conduit model. The model combines stress-strain responses from concrete compression experiments with detailed crack data, providing a realistic representation of crack development under varying load conditions. By implementing both unlubricated and lubricated compression tests, different failure modes were observed, influencing penetration patterns. Simulations show that the distribution of cracks significantly accelerates moisture penetration within the concrete. Notably, uniformly distributed cracks, typical of lubricated tests, facilitate deeper and faster moisture transport compared to more localized cracks observed in unlubricated tests. This study validates the …

Numerical Study On The Flexural Behaviour Of Asr-Affected Prestressed Concrete Girders Considering Crack Morphology, Abdallah Mohamed Elmasry, Xi Ji, Hyo Eun Joo, Yuya Takahashi

International Conference on Durability of Concrete Structures

The alkali-silica reaction (ASR) significantly compromises the structural integrity of reinforced concrete members, underscoring the need for reliable computational models to assess ASR-affected infrastructure, especially in regions like Japan, where this issue is prevalent. Prestressed concrete (PC) girders develop anisotropic cracking under ASR-induced expansion, resulting in direction-dependent mechanical properties that can influence their global structural performance. In this study, the flexural behaviour of ASR-deteriorated PC girders with varying prestress and expansion levels is investigated numerically using the COM3 computational framework, which integrates constitutive laws for ASR-damaged concrete. The model’s ability to capture anisotropic mechanical behaviour is first evaluated by simulating …

Development Of Mesoscale Model For Volumetric Deformation Of Cementitious Materials In Deep-Sea Environment, Taito Miura, Ryosuke Hatta, Ryuta Amatsubo, Yuchiro Kawabata, Keisuke Takahashi

International Conference on Durability of Concrete Structures

This study developed a mesoscale mechanical model capable of reproducing the volumetric deformation behaviour of cementitious materials in deep-sea environments. In the analysis, the rigid-body spring model (RBSM), a mesoscale mechanical model, was integrated with a truss network model (TNM) capable of evaluating mass transport, forming the RBSM-TNM framework. To assess the volumetric change of the skeleton under hydrostatic pressure, a creep model was applied to the mechanical springs representing the mechanical response of the skeleton. Additionally, the truss network model was employed to evaluate water penetration from the surface. Furthermore, based on the concept of poromechanics, the model was …

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 …

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 …

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.

Individuals’ Experiences Of Care Partner Involvement In Heart Disease Management: A Pilot Study, Elizabeth Richards

School of Nursing Faculty Publications

Introduction: Heart disease impacts both those diagnosed and their families, often due to lifestyle modifications that can alter family dynamics. While existing literature focuses on men and married individuals, understanding care partner involvement for both men and women independent of marital status is important, given gender disparities in heart disease experiences, caregiving roles, and widowhood rates. We explored differences in characteristics of men and women with heart disease, with and without a care partner. Additionally, we explored involvement of care partner beyond spousal relationships. We further examined gender differences in these experiences. Method: Cross-sectional Prolific survey pilot data of persons …

Reference At A Remote Field Station: A Case Study Of Ecology, Environmental Science And Geology Fieldwork At An Embedded Library, Thomas Gerrish

Libraries Faculty and Staff Scholarship and Research

Purpose Field station libraries, particularly those serving biological and marine research stations, represent a unique but understudied class of special libraries. This case study investigates reference services at the remote University of Michigan Biological Station (UMBS) to provide a baseline assessment of how such services support the information needs related to research in ecology, geology and environmental science.

Design/methodology/approach The study recorded, coded and analyzed 209 reference transactions from the 2022 and 2023 summer sessions, revealing trends in patron inquiries and the role of the reference desk. Further, the case study examined the organizational structure, community interaction and mission of …

Book Review Of Koan Khmer: A Novel, Christine Su

Journal of Southeast Asian American Education and Advancement

On rare occasions, I come across a book that truly resonates with me, with storylines and narrator enquiries that echo my own, and characters whose dispositions harken back to my own family members, friends, and myself. As the U.S.-born daughter of a Khmer (Cambodian) father, this is a rare occurrence. This is not to say that I do not enjoy reading works of fiction that transport me to other worlds or allow me to see things through the eyes of someone whose experiences are vastly different than mine—I do. Yet I long for narratives that offer familiarity, understanding, and a …

“If I Ruled The World”: Deploying Spatial Imaginaries For Examining Anti-Blackness And Space In Precollege Engineering Education, Christopher Wright, Monet V. F. Harbison

Journal of Pre-College Engineering Education Research (J-PEER)

Engineering’s systemic exclusion of Black people has been a decades-long inquiry. While critical race theory and community cultural wealth have been utilized to examine anti-Blackness in precollege engineering education, critical geographies have been underutilized. This essay contends that the deployment of a spatial imaginaries lens could be used to expand understandings of the spatial imaginary of anti-Blackness in the discipline. Using historical and contemporary data from an engineering high school as well as nonpositivist ways of knowing, the essay contends that examining spatial realities and underpinnings are opportune provocations for redefining purposes, assumptions, and values in precollege engineering education.

Public Perceptions Of Universities As Public Entities During The Covid-19 Pandemic Era, Jinho Jung, Laura Barrett, Nicole Olynk Widmar, Mario Ortez

Department of Agricultural Economics Faculty Publications

Higher education institutions are facing challenges in navigating social, cultural, and political issues. The online presence of higher education presents a new set of opportunities and challenges; knowledge, news, and continuing education are increasingly disseminated online. Additionally, the public, student bodies and stakeholders are increasingly looking at reviews or seeking opinions via online and social media to form opinions on institutions. This analysis uses online and social media to analyze and compare perceptions of two public universities in Indiana, namely Purdue University and Indiana University. These two Indiana institutions are located in the same state, allowing for comparisons of public …

Challenging The School Boundaries: Exploring Challenges And Opportunities In Homeschooling Engineering Education, Luis Montero-Moguel, Cynthia Lima, Guadalupe Carmona, Verónica Vargas-Alejo

Journal of Pre-College Engineering Education Research (J-PEER)

Homeschooling sparks controversy regarding the quality of education when compared to the traditional schooling system. However, homeschooling rates have doubled nationwide since the pandemic, especially among minorities. Funding and curricular material resources may be limited for homeschooling families, especially those from diverse backgrounds. Therefore, this essay discusses the need to expand the current boundaries of engineering education to include homeschooling communities. Drawing from our homeschooling experience, we present three recommendations that respect the cultures and unique characteristics of homeschooling to promote engineering practices in these communities. Our proposal challenges negative perceptions of homeschooling, enhancing our understanding of its unique characteristics …