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Full-Text Articles in Civil and Environmental Engineering

The Professional Constructor, Full Issue, Volume 49, Number 01 Mar 2024

The Professional Constructor, Full Issue, Volume 49, Number 01

The Professional Constructor

No abstract provided.


Mixed Reality For In-Field Construction Activities: A Systematic Literature Review To Identify Challenges And Solutions, Sumanth Sai. P., Jason Lucas Mar 2024

Mixed Reality For In-Field Construction Activities: A Systematic Literature Review To Identify Challenges And Solutions, Sumanth Sai. P., Jason Lucas

The Professional Constructor

With the new industrial revolution, “Industry 4.0,” it is important to understand and incorporate the new standards and technologies evolving in the market. Industry 4.0 relies on the integrated use of big data and analytics coupled with various technologies to help make decisions and manage projects. This revolution has brought Mixed Reality (MR) into the construction field. Mixed reality (MR) offers significant benefits for smart industries, such as enhancing productivity, training, manufacturing, error correction, assembly, and packaging processes. But how feasible are Mixed Reality Technologies (MRTs) considering the high initial investment required for acquiring devices, subscribing to services, planning and …


Computer-Integrated Construction Management With Procore, Vedanth Ashoka, M.G. Matt Syal Mar 2024

Computer-Integrated Construction Management With Procore, Vedanth Ashoka, M.G. Matt Syal

The Professional Constructor

The construction industry faces difficulties in managing the enormous amounts of data generated at each stage of a project, impacting project coordination and decision-making. Currently the industry is facing the issue of a lack of interoperability among the multiple software programs being used for different functions. To address this lack of interoperability, there is a need for an integrated environment that allows seamless flow of data between different functions. Among the few software tools that have emerged in recent year, Procore, a cloud-based construction project management software, has emerged as a widely used solution in the industry, enabling collaboration among …


Wave Overtopping Layer Thickness On The Crest Of Rubble Mound Seawalls, Ali Koosheh, Amir Etemad-Shahidi, Nick Cartwright, Rodger Tomlinson, Marcel R. A. Van Gent Mar 2024

Wave Overtopping Layer Thickness On The Crest Of Rubble Mound Seawalls, Ali Koosheh, Amir Etemad-Shahidi, Nick Cartwright, Rodger Tomlinson, Marcel R. A. Van Gent

Research outputs 2022 to 2026

During storms, ensuring the protection of people, vehicles and infrastructure on the crest of coastal structures from wave overtopping hazards is crucial. The thickness of the wave overtopping layer is a key variable used for assessing safety and maintaining a secure design. Traditionally, this parameter is associated with the height difference between the fictitious wave run-up level exceeded by 2% of waves and the crest freeboard of coastal structures. This study aims to investigate the wave overtopping layer thickness on the crest of rubble mound seawalls. To achieve this, a series of 125 small-scale 2D physical model tests were conducted …


Applicability Of Using Bio-Receptive Concrete For Building Facades In Egypt, Gina Roupheil Feb 2024

Applicability Of Using Bio-Receptive Concrete For Building Facades In Egypt, Gina Roupheil

Theses and Dissertations

The significant increase in carbon dioxide emissions caused by the construction industry is detrimental to our planet. This is rapidly increasing with the urbanization of cities that is gradually taking its toll on the available green spaces, which help in balancing such emissions. Recently, researchers have been trying to make use of bio-receptivity to create biomaterial systems that could be spread on building envelopes and support the growth of small plant species and microorganisms to establish on. Out of those materials, comes the concrete as a promising material for bio-colonization.

Within this context, this study aims at investigating the applicability …


Thermal Insulation And Fire Protection Plaster For Frp System Incorporating Aerogel Nanoparticles And Phyllosilicates, Athnasious Ghaly Feb 2024

Thermal Insulation And Fire Protection Plaster For Frp System Incorporating Aerogel Nanoparticles And Phyllosilicates, Athnasious Ghaly

Theses and Dissertations

For more than two decades, new innovative materials have been introduced to the market such as nano materials that can be utilized for their high performance in different aspects of the construction industry. Structural repair and strengthening is one of the most demanding fields in the construction industry for innovative and high-performance materials due to its specialty. Time, quality, economy, and sustainability are the main factors that control this field, and for that, new systems keep being introduced to the market to reduce the time of repair and enhance its efficiency. Fiber Reinforced Polymers (FRP) Systems are the most advanced …


Properties Of Portland Cement Concrete Incorporating Basalt-Based Pozzolanic Cement, Rana Khalil Feb 2024

Properties Of Portland Cement Concrete Incorporating Basalt-Based Pozzolanic Cement, Rana Khalil

Theses and Dissertations

Over the last decade, the world's population has increased dramatically. Due to this growth, the demand for concrete and Portland cement, in return, have increased. Manufacturing of Portland cement is an energy-intensive process that, alone, contributes to about 8% of global CO2. For decades, efforts have been exerted to reduce the harmful environmental impacts of Portland cement by reducing its use in concrete as well as considering alternate binders that may fully or partially replace it. This study aims to assess the properties of concrete incorporating a novel basalt-based pozzolanic cement. To meet this objective, four sets of concrete mixtures …


Prediction Of Distresses In Pavement Networks: A Machine Learning Approach, Mahmoud Kotb Feb 2024

Prediction Of Distresses In Pavement Networks: A Machine Learning Approach, Mahmoud Kotb

Theses and Dissertations

The quality of pavement networks is greatly affected by different distresses. These distresses appear in many forms, such as cracking, potholes, rutting and different types of deformation. As a result, to ensure effective pavement management, accurate modeling of these different distresses has become essential. Moreover, machine learning models have shown great potential in modeling pavement performance in recent years. The objective of this research is to develop machine learning models for modeling key parameters of pavement distress, specifically the International Roughness Index (IRI), fatigue and longitudinal cracking. Data for this investigation were extracted from the Long-Term Pavement Performance (LTPP) database, …


Assessing Adoption Barriers Of Sustainable Packaging In Egypt, Carol Ramses Morgan Feb 2024

Assessing Adoption Barriers Of Sustainable Packaging In Egypt, Carol Ramses Morgan

Theses and Dissertations

Sustainable packaging has become an essential part of business decisions and corporate directions. With the rise of environmental damages due to improper waste management and unsustainable practices, businesses have a major responsibility to analyze their products’ life cycles and redesign them with sustainability in mind. Applying sustainable packaging could save companies large amounts of resources, therefore cutting costs, while also achieving the legal and social duty as a corporation towards society and the environment. Many developing countries, with specific focus on Egypt, have recently focused on legislative and corporate decisions in order to encourage more sustainable practices. Egypt’s new Waste …


Research And Optimization Of Yolo-Based Method For Automatic Pavement Defect Detection, Hui Yao, Yaning Fan, Xinyue Wei, Yanhao Liu, Dandan Cao, Zhanping You Feb 2024

Research And Optimization Of Yolo-Based Method For Automatic Pavement Defect Detection, Hui Yao, Yaning Fan, Xinyue Wei, Yanhao Liu, Dandan Cao, Zhanping You

Michigan Tech Publications

According to the latest statistics at the end of 2022, the total length of highways in China has reached 5.3548 million kilometers, with a maintenance mileage of 5.3503 million kilometers, accounting for 99.9% of the total maintenance coverage. Relying on inefficient manual pavement detection methods is difficult to meet the needs of large-scale detection. To tackle this issue, experiments were conducted to explore deep learning-based intelligent identification models, leveraging pavement distress data as the fundamental basis. The dataset encompasses pavement micro-cracks, which hold particular significance for the purpose of pavement preventive maintenance. The two-stage model Faster R-CNN achieved a mean …


Dynamics Of Nanocluster Aerosol In The Indoor Atmosphere During Gas Cooking, Satya S. Patra, Jinglin Jiang, Xiaosu Ding, Chunxu Huang, Emily K. Reidy, Vinay Kumar, Paige Price, Connor Keech, Gerhard Steiner, Philip Stevens, Nusrat Jung, Brandon E. Boor Feb 2024

Dynamics Of Nanocluster Aerosol In The Indoor Atmosphere During Gas Cooking, Satya S. Patra, Jinglin Jiang, Xiaosu Ding, Chunxu Huang, Emily K. Reidy, Vinay Kumar, Paige Price, Connor Keech, Gerhard Steiner, Philip Stevens, Nusrat Jung, Brandon E. Boor

Purdue University Libraries Open Access Publishing Fund

Nanocluster aerosol (NCA: particles in the size range of 1–3 nm) are a critically important, yet understudied, class of atmospheric aerosol particles. NCA efficiently deposit in the human respiratory system and can translocate to vital organs. Due to their high surface area-to-mass ratios, NCA are associated with a heightened propensity for bioactivity and toxicity. Despite the human health relevance of NCA, little is known regarding the prevalence of NCA in indoor environments where people spend the majority of their time. In this study, we quantify the formation and transformation of indoor atmospheric NCA down to 1 nm via high-resolution online …


Developing And Forecasting The Egyptian Construction Cost Index, Mayada Elsaied Feb 2024

Developing And Forecasting The Egyptian Construction Cost Index, Mayada Elsaied

Theses and Dissertations

Accurate cost estimation is pivotal for the success of construction projects, yet the industry grapples with challenges related to cost overruns. Uncertainties and unforeseen variables often introduce discrepancies, particularly during the planning phase. Economic changes, considered uncontrollable risks, significantly influence these fluctuations. Various research endeavors have quantified the impact of economic conditions on construction costs, emphasizing the correlation between economic indicators and project expenses. Addressing these challenges, the Construction Cost Index (CCI), a tool introduced by Engineering News Record (ENR), accurately delineates the correlation between economic changes and construction costs. Despite its global efficacy, an Egyptian Construction Cost Index is …


Water Stress Index And Stomatal Conductance Under Different Irrigation Regimes With Thermal Sensors In Rice Fields On The Northern Coast Of Peru, Lia Ramos-Fernández, Maria Gonzales-Quiquia, José Huanuqueño-Murillo, David Tito-Quispe, Elizabeth Heros-Aguilar, Lisveth Flores Del Pino, Alfonso Torres-Rua Feb 2024

Water Stress Index And Stomatal Conductance Under Different Irrigation Regimes With Thermal Sensors In Rice Fields On The Northern Coast Of Peru, Lia Ramos-Fernández, Maria Gonzales-Quiquia, José Huanuqueño-Murillo, David Tito-Quispe, Elizabeth Heros-Aguilar, Lisveth Flores Del Pino, Alfonso Torres-Rua

Civil and Environmental Engineering Faculty Publications

In the face of the climate change crisis, the increase in air temperature negatively impacts rice crop productivity due to stress from water scarcity. The objective of this study was to determine the rice crop water stress index (CWSI) and stomatal conductance (Gs) under different irrigation regimes, specifically continuous flood irrigation treatments (CF) and irrigations with alternating wetting and drying (AWD) at water levels of 5 cm, 10 cm, and 20 cm below the soil surface (AWD5, AWD10, and AWD20) in an experimental area of INIA-Vista Florida and in six commercial areas of the …


Reliability Improvement In The Traction System Of Tanzania Standard Gauge Railway, Yusufu Katuga Feb 2024

Reliability Improvement In The Traction System Of Tanzania Standard Gauge Railway, Yusufu Katuga

Tanzania Journal of Engineering and Technology (TJET)

In recent years, many African governments have been developing Standard Gauge Railway (SGR) to replace the old after becoming absolute, inefficient Meter Gauge System (MGR) to carry more loads at high mileage and speed while combating the oil and environmental crises. With the increase of SGR, the amount of traction systems has grown sharply, the service life of the traction system has increased gradually, and the components of the vehicle traction system have become worn and aged as a result. While Tanzania is transitioning to SGR with its gradually increasing traction systems, reliability improvement becomes a key for the sustainability …


Absorbance Enhancement Of A Treated Tanzanian Kaolin For Removal Of Synthetic Dyes From Water, Samwel Paul Mziray Feb 2024

Absorbance Enhancement Of A Treated Tanzanian Kaolin For Removal Of Synthetic Dyes From Water, Samwel Paul Mziray

Tanzania Journal of Engineering and Technology (TJET)

The absorbance efficiency of local kaolin clay from Tanzania (Pugu kaolin) has been enhanced to improve its utilization in removal of textile dyes from water. The clay was acid-activated using H2SO4, after calcination at 750oC. Characterization by XRF, XRD, ATR-FTIR and Porosimeter showed kaolinite [Al2Si2O5(OH)4], silica (SiO2) and microcline [KAlSi3O8] as the main phases. Upon acid treatment, silica increased from 44.18% to 58.81% due to the appearance of tridymite, and alumina decreased from 26.70% to 12.74% due to disappearance of the kaolinite. Surface area increased from 15.36 to 149.61 m2/g due to removal of acid-soluble impurities. The chemical composition showed …


Sustainability Of Simplified Sewer Systems: A Case Study Of Vingunguti Urban Settlement, Dar Es Salaam Region In Tanzania, Neema Kijazi Feb 2024

Sustainability Of Simplified Sewer Systems: A Case Study Of Vingunguti Urban Settlement, Dar Es Salaam Region In Tanzania, Neema Kijazi

Tanzania Journal of Engineering and Technology (TJET)

The universal access to safely managed sanitation remains one of the challenges to achieving the UN SDG target 6.2 in unplanned urban settlements including the Vingunguti area in Dar es Salaam City which is high-density populated. In an attempt to address this challenge, a simplified sewer system was piloted as an option for achieving safely managed sanitation in this particular area. The objective of this study was to assess the sustainability of the piloted simplified sewer system for its potentiality to up-scale and replication in areas with similar sanitation challenges in the country. Methodology involved collection of data on performance …


Steminism: Analyzing Factors That Improve Retention Of Women In Stem, Kira Carter, Jane Kelley, Jason Vasser-Elong, Rc Patterson Feb 2024

Steminism: Analyzing Factors That Improve Retention Of Women In Stem, Kira Carter, Jane Kelley, Jason Vasser-Elong, Rc Patterson

Dissertations

Our co-authored research ‘Steminism: Analyzing Factors That Improve Retention for Women as STEM Majors’ analyzed factors that contributed to the retention of women in science, technology, engineering, and mathematics (STEM) programs at Missouri University of Science & Technology (Missouri S&T). Women make up half of the US population, and while careers in (STEM) are an integral part of the US economy, women are underrepresented in these career fields. The purpose of our dissertation is to address the underrepresentation of women in STEM majors. Our methodology included homogeneous sampling to collect qualitative data. More specifically, we consulted with academic advisors and …


Hybrid Hydrolysis And Fermentation Of Prosopis Juliflora Pods For Biohydrogen Production By Dark Fermentation, Gayathri G Feb 2024

Hybrid Hydrolysis And Fermentation Of Prosopis Juliflora Pods For Biohydrogen Production By Dark Fermentation, Gayathri G

Theses and Dissertations

The rapid consumption of fossil fuels has resulted in the energy crisis and many environmental issues, including air pollution and the greenhouse effect. Hydrogen is the independent source of the highest energy content, with 122 KJ g-1. Biohydrogen produced from lignocellulosic biomass (LCB) is an excellent alternative fuel for its cleanability, renewability and sustainability. Biohydrogen production from dark fermentation using lignocellulosic biomass provides low cost and a sustainable pathway to utilize a vast amount of waste.

Dark fermentation has considerable potential for hydrogen production because it does not require sunlight, allowing for full-time operation and minimizing bioreactor complexity. The major …


Energy System For Evaluation Of Modification Methods On Energy Transfer Efficiency And Optimization Ofmembranes, Tian Li, Hong Zhou, Wei Ding, Jinjun Wang, Tiancheng Zhang Feb 2024

Energy System For Evaluation Of Modification Methods On Energy Transfer Efficiency And Optimization Ofmembranes, Tian Li, Hong Zhou, Wei Ding, Jinjun Wang, Tiancheng Zhang

Department of Civil and Environmental Engineering: Faculty Publications

Saving energy is crucial for utilizing membrane technology, but there is no energy parameter for understanding the relationships among membrane performance and energy. Here, φ is defined as the energy transfer efficiency of the membrane, and its numerical expression of membrane performance is poor (e.g., in the range of 10−23). The method of modifying membranes is a crucial determinant for developing membrane science, but researchers using current parameters to evaluate modification methods might lead to erroneous conclusions. Hence, the newly established system θ is used to analyze the influence of different modification methods on energy consumption, which not …


Evolution Of Sbs-Modified Asphalt Performance Under Aging And Rejuvenation Cycle Conditions, Ke Shi, Feng Ma, Jenny Liu, Zhen Fu, Ruimeng Song, Dongdong Yuan, Aboudou Wassiou Ogbon Feb 2024

Evolution Of Sbs-Modified Asphalt Performance Under Aging And Rejuvenation Cycle Conditions, Ke Shi, Feng Ma, Jenny Liu, Zhen Fu, Ruimeng Song, Dongdong Yuan, Aboudou Wassiou Ogbon

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Improving the poor long-term service performance of rejuvenated SBS-modified asphalt (REF-LT) is highly challenging. In this study, a blend of aged and virgin binders was used to rejuvenate REF-LT and the evolution of the asphalt performance was observed during regeneration and reaging processes. An SBS-modified asphalt (SBM) and base asphalt (BA) were mixed with REF-LT in specified ratios to prepare SBM- and BA-rejuvenated asphalts. The rejuvenated asphalts were subjected to short- and long-term aging. The high/low-temperature rheological properties, fatigue resistance, rejuvenation mechanism, and changes in the functional groups of the rejuvenated and reaged asphalts were characterized using a dynamic shear …


Characterization Of Alkali-Silica Reaction (Asr) Products And C-S-H Using Swir Spectroscopy For Nondestructive Detection Of Asr, Pengfei Ma, Wenyu Liao, Ying Zhuo, Hongyan Ma, Yanping Zhu, Genda Chen Feb 2024

Characterization Of Alkali-Silica Reaction (Asr) Products And C-S-H Using Swir Spectroscopy For Nondestructive Detection Of Asr, Pengfei Ma, Wenyu Liao, Ying Zhuo, Hongyan Ma, Yanping Zhu, Genda Chen

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study explores the feasibility of characterizing alkali-silica reaction (ASR) products and calcium silicate hydrates (C-S-H) from short-wave infrared (SWIR) spectroscopy. ASR products and C-S-H samples with different Ca/Si ratios were synthesized and analyzed through XRD, 29Si nuclei magnetic resonance (NMR) and SWIR spectroscopy. Fourier-transform infrared spectroscopy (FTIR) was collected to help interpret the results from the SWIR spectroscopy. The obtained spectroscopic features were applied to quantify the ASR product abundance denoted by the length expansion of mortar bars after an accelerated ASR test. The results show that the SWIR spectra of the synthetic ASR gels are similar regardless of …


Numerical And Experimental Investigation Of Negative Stiffness Beams And Honeycomb Structures, Yasser Darwish, Mohamed A. Elgawady Feb 2024

Numerical And Experimental Investigation Of Negative Stiffness Beams And Honeycomb Structures, Yasser Darwish, Mohamed A. Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Metamaterial structures that exhibit negative stiffness (MSNS) behavior have shown the potential to be used as energy dissipation systems in different applications. Negative stiffness honeycomb structures consist of multiple pre-buckled beams that snapping through from one pre-buckled mode to another buckled mode, when subjected to transverse loads, displaying negative stiffness, and dissipating a significant portion of the input energy. This paper presents finite element models (FEMs) developed to investigate the performance of negative stiffness pre-buckled beams and honeycombs. The FEMs were validated using experimental results of single pre-buckled beams and honeycomb structures. The experimental testing of the pre-buckled beams was …


An Innovative Fracture Plugging Evaluation Method For Drill-In Fluid Loss Control And Formation Damage Prevention In Deep Fractured Tight Reservoirs, Chengyuan Xu, Lei Liu, Yang Yang, Yili Kang, Zhenjiang You Feb 2024

An Innovative Fracture Plugging Evaluation Method For Drill-In Fluid Loss Control And Formation Damage Prevention In Deep Fractured Tight Reservoirs, Chengyuan Xu, Lei Liu, Yang Yang, Yili Kang, Zhenjiang You

Research outputs 2022 to 2026

Lost circulation, resulting from the undesired loss of drilling fluid into formation fractures, stands as a significant technical obstacle in the exploration and production of oil, gas, and geothermal reservoirs. Effective mitigation of this challenge requires the development and application of robust experimental evaluation methods to assess the effectiveness of fracture plugging. The traditional approach to fracture plugging evaluation relies on a uniform evaluation index and experimental parameters for various lost circulation types. Unfortunately, this practice frequently results in inconsistent performance of loss control formulas during laboratory experiments and field tests. To address this issue, this paper introduces an innovative …


Blood Lead, Cadmium And Hair Mercury Concentrations And Association With Soil, Dust And Occupational Factors In E-Waste Recycling Workers In Bangladesh, Sarker Masud Parvez, Farjana Jahan, Jaynal Abedin, Mahbubur Rahman, Shaikh Sharif Hasan, Nafisa Islam, Nirupam Aich, Mohammad Moniruzzaman, Zahir Islam, Masatake Fujimura, Rubhana Raqib, Luke D. Knibbs, Peter D. Sly Feb 2024

Blood Lead, Cadmium And Hair Mercury Concentrations And Association With Soil, Dust And Occupational Factors In E-Waste Recycling Workers In Bangladesh, Sarker Masud Parvez, Farjana Jahan, Jaynal Abedin, Mahbubur Rahman, Shaikh Sharif Hasan, Nafisa Islam, Nirupam Aich, Mohammad Moniruzzaman, Zahir Islam, Masatake Fujimura, Rubhana Raqib, Luke D. Knibbs, Peter D. Sly

Department of Civil and Environmental Engineering: Faculty Publications

Background: Electronic waste (e-waste) recycling activities release toxic metals, which pose substantial hazard to the environment and human health. We evaluated metal concentrations in biological and environmental samples, and examined the associations between biological lead (Pb), cadmium (Cd), and mercury (Hg) with soil and dust metals, and other possible determinants, among populations exposed and non-exposed to e-waste in Bangladesh.

Methods: A total of 199 e-waste workers and 104 non-exposed individuals were recruited. We measured blood Pb (BPb) and Cd (BCd) concentrations and total Hg (THg) from hair samples. Data were collected on occupational, and behavioral factors. We fitted …


A Systematic Review Of Fourth Industrial Revolution Technologies In Smart Irrigation: Constraints, Opportunities, And Future Prospects For Sub-Saharan Africa, Joshua Wanyama, Erion Bwambale, Shafik Kiraga, Abia Katimbo, Prossie Nakawuka, Isa Kabenge, Isaac Oluk Feb 2024

A Systematic Review Of Fourth Industrial Revolution Technologies In Smart Irrigation: Constraints, Opportunities, And Future Prospects For Sub-Saharan Africa, Joshua Wanyama, Erion Bwambale, Shafik Kiraga, Abia Katimbo, Prossie Nakawuka, Isa Kabenge, Isaac Oluk

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The adoption of Fourth Industrial Revolution (4IR) technologies has revolutionized agricultural practices worldwide. However, their application in the context of sub-Saharan Africa remains a critical challenge. This study presents a systematic review that investigates the potential of 4IR technologies in smart irrigation. Sub- Saharan Africa faces multiple agricultural challenges, exacerbated by climate change, water scarcity, and inefficient irrigation practices. The need for sustainable, water-efficient, and data-driven irrigation systems is urgent to ensure food security and economic development in the region. This study addresses a crucial knowledge gap by assessing the constraints, opportunities, and prospects of implementing 4IR technologies for smart …


Advanced Shape Memory Alloy Fibers Designed To Enhance Crack Closure And Re-Centring Performance In Cement-Based Composites, Ayoub Dehghani, Farhad Aslani Feb 2024

Advanced Shape Memory Alloy Fibers Designed To Enhance Crack Closure And Re-Centring Performance In Cement-Based Composites, Ayoub Dehghani, Farhad Aslani

Research outputs 2022 to 2026

Crack-closing and re-centring attributes were observed in cementitious composites utilising segmented pseudoelastic shape memory alloy fibres (S-PSMAFs) developed in this study. S-PSMAFs, produced via laboratory deep drawing, displayed notable strain recovery capacity during detwinning and martensite phases in direct cyclic tensile tests. Cementitious composites incorporating S-PSMAFs at 0.5%, 0.75%, and 1.0% dosages underwent testing in static and cyclic flexure using both unnotched and notched beams. Results were compared with steel fibre (SF) reinforced specimens. Digital image correlation (DIC) provided full-field strain maps and crack propagation data. The cyclic testing allowed assessment of crack-closing and re-centring behaviour at varying deflections post-cracking …


Buckling Behavior Of Thin Wall Stiffened Cylindrical Shells Through Ml Techniques, Fnu Tabish, Muhammad Hamza Karim, Rajesh Godasu, Iraj H.P Mamaghani Feb 2024

Buckling Behavior Of Thin Wall Stiffened Cylindrical Shells Through Ml Techniques, Fnu Tabish, Muhammad Hamza Karim, Rajesh Godasu, Iraj H.P Mamaghani

SDSU Data Science Symposium

Stiffened cylindrical shell buckling strength mainly depends on the geometric and stiffness properties. A detailed parametric study was conducted to investigate the influence of these properties on the stiffened aluminium cylindrical shell buckling strength. The proposed framework involves an integration of finite element method and various machine learning techniques. The dataset obtained from the eigenvalue buckling analysis of 350 numerical simulations using ANSYS workbench 2022; however, the FE simulation of ten ring-stiffened cylindrical specimens was initially substantiated by experimental work conducted in the literature. 350 sample specimens were categorized into seven groups based on the no. of stiffeners varying from …


Wearable Mxene-Graphene Sensing Of Influenza And Sars-Cov-2 Virus In Air And Breath: From Lab To Clinic, Yanxiao Li, Zhekun Peng, Jiaoli Li, Congjie Wei, Shangbin Liu, Weixing Hao, Huanyu Cheng, Casey Burton, Yang Wang, Yue-Wern Huang, Chang Soo Kim, Fang Yao Stephen Hou, Donghyun (Bill) Kim, Chenglin Wu Feb 2024

Wearable Mxene-Graphene Sensing Of Influenza And Sars-Cov-2 Virus In Air And Breath: From Lab To Clinic, Yanxiao Li, Zhekun Peng, Jiaoli Li, Congjie Wei, Shangbin Liu, Weixing Hao, Huanyu Cheng, Casey Burton, Yang Wang, Yue-Wern Huang, Chang Soo Kim, Fang Yao Stephen Hou, Donghyun (Bill) Kim, Chenglin Wu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The rapidly expanding severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants demand a continuous monitoring method through portable and wearable devices. Utilizing the rich surface chemistry and high chemical-to-electrical signal conversion of 2D MXene-graphene heterostructure thin films, a field-effect-transistor (FET) sensor, which has a flexible substrate to be assembled onto the mask and combines with a Bluetooth system for wireless transmission is developed, to detect the influenza and SARS-CoV-2 viruses in air and breath. At first, the developed sensors are examined in the laboratory through direct contact with sensing targets in solution form. The results show a low …


Synergistic Effect Of Macro Synthetic Fiber And Shrinkage-Reducing Admixture On Engineering Properties Of Fiber-Reinforced Super-Workable Concrete, Jingjie Wei, Nima Farzadnia, Kamal H. Khayat Feb 2024

Synergistic Effect Of Macro Synthetic Fiber And Shrinkage-Reducing Admixture On Engineering Properties Of Fiber-Reinforced Super-Workable Concrete, Jingjie Wei, Nima Farzadnia, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study aims to enhance fiber-reinforced super-workable concrete (FR-SWC) by optimizing the system of shrinkage-reducing admixture (SRA) and macro-synthetic fiber (MSF) for low shrinkage and uncompromised mechanical properties. A factorial design approach was employed to model the effect of fiber content, SRA dosage, and combined ratios of two types of MSF on performance of FR-SWC. MSF content had the greatest impact on mechanical properties, followed by SRA and MSF combination. Using MSF increased equivalent flexural strength ratio by 310% compared to the control mixture, regardless of MSF combination and SRA. SRA had the most significant effect on drying shrinkage, followed …


From Pumping To Deposition: A Comprehensive Review Of Test Methods For Characterizing Concrete Printability, Ali Fasihi, Nicolas A. (Ali) Libre Feb 2024

From Pumping To Deposition: A Comprehensive Review Of Test Methods For Characterizing Concrete Printability, Ali Fasihi, Nicolas A. (Ali) Libre

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

3D concrete printing (3DCP) technology has gained significant attention in the construction industry due to its potential to revolutionize the way buildings are designed and constructed. However, successful application of 3DCP requires robust standard test procedures to characterize the printability of concrete. Printability is a measure of workability for a printing material in the 3DCP process, which is characterized by pumpability, extrudability, and buildability. This paper presents a comprehensive review of the test methods that could be used for material characterization during various printing steps, including pumping, extrusion, and layer deposition. The underlying mechanisms relevant to each step, key governing …