Architectural Engineering Commons^™

Effect Of Absorption Kinetics Of Superabsorbent Polymers On Printability And Interlayer Bond Of 3d Printing Concrete, Yu Cun Gu, Shuyi Zheng, Hongyan Ma, Wu Jian Long, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study examines the effect of the material characteristics of superabsorbent polymers (SAPs) on the printability and interlayer bond strength of 3D printing concrete. Three types of SAP, including two acrylamide-co-acrylic polymers with coarse and fine particle sizes (S1 and S2) and an acrylic copolymer (S3), were employed. The investigated mortar mixtures had a fixed initial mini-slump flow of 195 ± 10 mm and yield stress of 290 ± 25 Pa. The fluidity of SAP-incorporated mortars was maintained by either adjusting the superplasticizer dosage or increasing the water content. Test results indicate that particle flocculation is dependent on SAP absorption …

Extrudability Window And Offline Test Methods To Predict Buildability Of 3d Printing Concrete, Yu Cun Gu, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This Study Investigates the Effect of Thixotropy and Stiffness Evolution on the Extrudability and Buildability of 3D Printing Concrete. Different Types of Supplementary Cementitious Materials and Limestone Filler Were Used to Prepare Mortars with Varying Levels of Thixotropy and Early-Age Stiffness. Mixtures with Yield Stress and Flocculation (Τfloc) of 180–400 and 420–950 Pa, Respectively, Exhibited Adequate Extrudability Without Plastic Collapse. the Printing Was Completed 8–15 Min after Mixing at a Vertical Build-Up Rate of 138 Mm/min. Several Process Parameters, Including Rest Time to Secure a Penetration Resistance of 150 KPa (T150) and Penetration Resistance at Various Rest Times Were Developed …

Rheology Modification Of Flowable Mortar With Co2, Sean Monkman, Soo Duck Hwang, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Rheological Properties of Mortar Samples with Different Additions of CO₂ during Mixing Were Determined. Flowable Cement-Based Mortars at Three Different W/c (0.55, 0.45 and 0.35) Were Produced and the Effects of CO₂ Gas Were Examined on the Fresh Properties of Slump Flow, Yield Stress and Plastic Viscosity. According to the Experimental Results, the Mortar Yield Stress and Plastic Viscosity Increased Faster over Time Than in a Reference System with the Increasing Addition of CO₂ and Greater Effects Were Seen at the Lowest W/c of 0.35 Than at the Others. the Impact of the CO₂ on …

Indefinability Of Effective Stress For Unsaturated Soils, Xiong Zhang, Sandra Houston

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

For decades, researchers have searched for an unsaturated soil effective stress that performs analogously to effective stress for saturated soils and provides some simplifications over net stress and suction approaches. A recent debate is whether problems identified with unsaturated soil effective stress can be resolved via elastoplastic analyses. Effective stress equations are reviewed and categorized as being based on volume change, shear strength, yield, or degree of saturation. These equations are evaluated for consistency with saturated soil effective stress expectations using the Barcelona basic model (BBM), simplified into an integrated elastoplastic framework using the modified state surface approach (MSSA). Under …

Timber Buckling Restrained Brace, Finn K. Burke

Architectural Engineering

Buckling Restrained Brace Frames (BRBs) are a lateral force resisting system providing near equal compressive and tensile capacities through the mitigation of compression buckling. BRBs have traditionally existed in the steel building market, with limited use in wood construction. The proposal of a Timber Bucking Restrained Brace Frame (TBRB) presents a BRB option for the low-rise and mid-rise wood framed market, using readily available materials within the low/mid-rise construction cost bracket. Five previous TBRB iterations have been built and tested, with results showing promising results for further TBRB development and exploration. The sixth and current iteration of the TBRB builds …

Carbon Capture And Renewable Energy Policies: Could Policy Harmonization Be A Puzzle Piece To Solve The Electricity Crisis?, Mahelet G. Fikru, Fateh Belaïd, Hongyan Ma

Economics Faculty Research & Creative Works

The electricity market crisis, driven by factors such as increased energy demand, rising fuel prices, aging infrastructure, and greenhouse gas emissions, requires a multifaceted approach including the strategic implementation of Carbon Capture and Storage (CCS) technologies, which despite high costs and potential adverse impact on renewable investments, can allow the use of fossil fuels to maintain grid stability, and simultaneously lower carbon footprint. Across the world, several nations are designing financial incentives and improving regulatory frameworks to reduce barriers to the deployment of CCS. However, it is not clearly understood whether and to what extent such policy support would affect …

Investigation Of Faults In Air-Conditioning Systems In Commercial Buildings: Occurrence, Diagnostic Validation, And Energy Impacts, Yuxuan Chen

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

In commercial buildings, fault detection and diagnosis (FDD) tools have been developed for detecting and diagnosing faults in building systems, which can provide useful information regarding fault locations and potential causes of faults, so that building operators and facility staff can be notified in time and quickly respond as problems arise. Nowadays, there are many commercial FDD tools available in the market, and these tools have been widely adopted in large- and medium-scale commercial buildings in the United States. Several studies have demonstrated the energy saving potential with the use of FDD in commercial HVAC systems, and one critical aspect …

Integrating Artificial Intelligence And Augmented Reality For Enhanced Task Performance In The Construction Industry, Aasish Chandrika Bhanu

All Dissertations

The Architecture, Engineering, and Construction (AEC) sector, characterized by its complex tasks, often faces challenges in adopting cutting-edge technologies, a trend that can significantly hinder productivity improvements compared to other industries. This dissertation explores the emerging integration of Artificial Intelligence (AI) and Augmented Reality (AR) within the AEC domain, investigating how effectively this can be implemented to potentially revolutionize industry practices. AI could be used in the AEC domain for advanced analytical and decision-making processes, while AR could be used for training, visualization, and remote collaboration.

In scenarios where construction site workers require expert guidance, these technologies could be helpful. …

Development Of Multivariate-Coupled Grouting Diffusion Model For Rcc, Xiao Sun, Yao Wang, Hengrui Liu, Zhuanjia Yang, Hongyan Ma

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Grouting Quality of Grout-Enriched Roller Compacted Concrete (RCC) is Difficult to Be Quantified Due to the Fact that the Crucial Effects, Such as Infiltration and the Compaction of the Skeleton of the RCC, Are Not Taken into Consideration. Combined with Model Testing, This Study Proposes an Improved Grouting Prediction Model Which Considers the Coupling Effect of Pore Fractal Properties, Time Variation of Grout Rheological Properties and Infiltration. Moreover, the Influence of Construction Parameters Such as Grouting Parameters, Construction Period Selection, Grouting Pipe Arrangement on the Grouting Effect Was Clarified. the Tests Indicated that the Maximum Diffusion Range of Slurry …

3d Printing Technology: Challenges, And Potentials In Achieving Sustainable Buildings, Sahar Mohamed Abd El Rahman, Sobhy Ibrahim Esmail

Journal of Engineering Research

The utilization of 3D printing technology in building construction has emerged as a promising approach with the potential to revolutionize the industry and significantly impact sustainability. This paper examines the role of 3D printing in building construction and explores its implications for sustainability. Through the ability to fabricate complex designs with precision and efficiency, 3D printing offers advantages such as reduced material waste, lower energy consumption, and decreased carbon emissions. Additionally, the use of locally sourced, recyclable materials combined with the customization capabilities of 3D printing enhances resource efficiency and minimizes environmental impact. Furthermore, the construction process is streamlined, leading …

Towards More Inclusive Cities By Promoting Diversity And Inclusion, Asmaa Mostafa Elshamy

Journal of Engineering Research

The primary goal of promoting diversity and inclusion in cities is to ensure that every individual regardless of race, gender, sexual orientation, socioeconomic status or ability feels valued, respected and included. It goes beyond mere tolerance and seeks to actively embrace and celebrate differences. By fostering inclusive environments, cities can harness the collective power and potential of their diverse populations, leading to enhanced social well-being, economic growth, and innovation. The need to harness the potential of diversity and inclusion to achieve full social, economic, and cultural benefits has become increasingly clear in recent years. This goes beyond just inclusion and …

Agility Opportunities In Construction Project Management “Exploring Opportunities In Construction Projects In Integration With Waterfall Methodology.”, Nevine G. Gado Dr., Noha A, Elsayed Dr

Journal of Engineering Research

The objective of project management for construction projects is to deliver projects that meet customer requirements, business values, and goals in the most efficient manner. Project management is considered one of the vastly debated fields currently while the commonly adopted approach is still the waterfall model. However, in today's construction market, the number of different stakeholders,’ and the way projects awarded are changing. This has created a gap between management's belief of how today's construction projects should be conducted and how they are executed. Despite the growing importance of traditional construction project management as the preferred project delivery method, there …

Spatial Environmental Suitability For The Localization Of Sanitary Waste Landfills In Egypt Using Environmental Information Systems: Applying To Safaga Qism, Wessam Mostafa Emam, Dalia Mahmoud Hassan

Journal of Engineering Research

This research focuses on the application of an environmental information system to help achieve balance and interrelation between the various environmental standards affecting the selection of the site to the sanitary landfill in the touristic Safaga qism of the Red Sea. According to the sustainable development strategy of Egypt’s Vision 2030, the issue of solid waste is one of the most important environmental challenge that faced sustainable development in Egypt. In light of the increasing number of unauthorized dumps of waste that pollute the environment, the Ministry of Environment adopted a national project to establish a network of sanitary landfills, …

Alhambra Alcazaba In Granada (Historical And Architectural Study), Ibrahim Abu Irmies

Journal of the Arab American University مجلة الجامعة العربية الامريكية للبحوث

The research focused on Alcazaba, fortress, of the Alhambra, located in the city of Granada in Al-Andalus, the reasons for its name, its geographical location, the reasons for its construction and how it is different from the old Alcazaba in Granada. It also discussed the historical stages of its construction since the era of the Umayyad State, the Zirid Dynasty as well as the era of the al-Muwahhidin and finally during the era of the state of Nasrid. The study was also supported by some evidence from the original historical sources, and important signs from the history of the internal …

The Architectural Characteristics Of The Palaces Of The Sultanate Of Al -Qaiti In Hadramout, Sabri Al-Tarimi, Fahed Jawher, Abdulaziz Al-Naggar

Journal of the Arab American University مجلة الجامعة العربية الامريكية للبحوث

The architectural characteristics of the Al -Qaiti palaces in Hadramout are one of the important topics that must be addressed to promote the architectural values and principles in those buildings and include them to the modern architectural style that expresses the architectural identity of the region. This study was divided into an introduction, analytical study, results and recommendations. The introduction included the research problem, the importance, objectives and methodology of research and the theoretical framework that included a historical overview of Hadramout and the history of the Sultanate of Al -Qaiti. In addition, a detailed and analytical explanation of the …

Form Pressure Exerted By Concrete For A Large-Scale Structure: Its Quantification And Physicochemical Interpretation, Tae Yong Shin, Seongho Han, Jin Hyun Lee, Jae Hong Kim

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Securing safety in formwork is one of the most important tasks to be carried out in the initial stage of construction. The form pressure exerted by fresh concrete needs to be identified, and it should be retained by a formwork system. A design pressure is given in literature and standards, but for large structures its precise prediction is required through a detailed analysis or a mock-up test. This study reports the lateral form pressure distribution generated by fresh concrete through a series of mock-up tests. The tests are designed considering the placement for nuclear containment structures; 3.4 m tall and …

Synergetic Effect Of Viscosity Modifying Admixtures And Polycarboxylate Ether Superplasticizer On Key Characteristics Of Thixotropic Uhpc For Bonded Bridge Deck Overlay Rehabilitation, Le Teng, Ming Jin, Jiadi Du, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Thin bonded ultra-high-performance concrete (UHPC) overlay is an advanced technology for bridge deck rehabilitation. UHPC should be tailored to secure adequate flowability and high thixotropy to facilitate mixing and placement with a low risk of sagging of the material on sloped bridge deck surfaces. The synergetic effect between nano clay (NC) and polycarboxylate ether (PCE) superplasticizer or cellulose-based viscosity modifying admixture (VMA) and PCE on the rheological properties (yield stress, plastic viscosity, and thixotropy), cement hydration, autogenous shrinkage, compressive strength, and porosity was systematically investigated. The bond strength between conventional concrete (CC) representing existing bridge deck concrete and thixotropic UHPC …

In Situ Synthesis, Characterization And Photocatalytic Efficacy Of Silver-Enhanced Mxene And Graphene Nanocomposites, Kishore Chand, M. Mustafa Azeem, Muhammad Nazim Lakhan, Mukhtiar Ahmed, Muhammad Jehanzaib Aslam, Ahmer Hussain Shah

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The emergence of 2D materials has significantly expanded the wide range of nanomaterials with diverse applications. Notably, their high conductivity, catalytic efficiency, and hydrophobicity have fueled heightened research interests for water treatment applications. This research aimed to investigate the synthesis and characterization of MXene and reduced graphene oxide (rGO) nanocomposites with silver nanoparticles (Ag) for enhanced catalytic activity in the decomposition of Direct Blue-24 dye. In this study, we employed well-established methods, previously documented in the literature, to prepare two distinct nanocomposites. Novel nanocomposites, namely reduced graphene oxide–silver nanoparticles (rGO–Ag) and MXene–silver nanoparticles (MXene–Ag), were synthesized using the hydrothermal and …

In Situ Synthesis, Characterization And Photocatalytic Efficacy Of Silver-Enhanced Mxene And Graphene Nanocomposites, Kishore Chand, M. Mustafa Azeem, Muhammad Nazim Lakhan, Mukhtiar Ahmed, Muhammad Jehanzaib Aslam, Ahmer Hussain Shah

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The emergence of 2D materials has significantly expanded the wide range of nanomaterials with diverse applications. Notably, their high conductivity, catalytic efficiency, and hydrophobicity have fueled heightened research interests for water treatment applications. This research aimed to investigate the synthesis and characterization of MXene and reduced graphene oxide (rGO) nanocomposites with silver nanoparticles (Ag) for enhanced catalytic activity in the decomposition of Direct Blue-24 dye. In this study, we employed well-established methods, previously documented in the literature, to prepare two distinct nanocomposites. Novel nanocomposites, namely reduced graphene oxide–silver nanoparticles (rGO–Ag) and MXene–silver nanoparticles (MXene–Ag), were synthesized using the hydrothermal and …

New Method To Calculate Friction Velocity In Smooth Channel Flows Using Direct Numerical Simulation Data, Harshit Mishra, S. Karan Venayagamoorthy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this paper, we leverage the direct numerical simulation (DNS) data for closed-channel flow for a range of friction Reynolds number (Reτ∼180-5,000) to develop a new one-point friction velocity method (OPFVM) to calculate friction velocity U∗ in terms of free-surface velocity Um, flow depth h, and kinematic viscosity ν. In contrast to prevalent methods that require several cumbersome near boundary measurements to obtain friction velocity, the OPFVM relies on a single easy-to-measure free-surface velocity measurement. The formulation is used to obtain friction velocity for a closed-channel flow (CCF) DNS regime with Reτ=10,049 and on four open-channel flow (OCF) DNS regimes …

Freezing-Thawing Hysteretic Behavior Of Soils, Jidong Teng, Antai Dong, Sheng Zhang, Xiong Zhang, Daichao Sheng

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The soil freezing characteristic curve (SFCC) plays a crucial role in investigating the soil freezing-thawing process. Due to the challenges associated with measuring the SFCC, there is a shortage of high-quality or rigorous test results with sufficient metadata to be effectively used for applications. Current researchers typically conduct freezing tests to measure the SFCC and assume a singular SFCC when studying the freezing-thawing process of soils, although limited studies indicated that there is a hysteresis during the freezing and thawing process. In this paper, a series of freezing-thawing tests were performed to assess the SFCC, utilizing a precise nuclear magnetic …

2023 Kahramanmaras Earthquake Sequence: Geospatial Visualization And Analysis Of Multiple Building Damage Datasets, Alejandra Bravo, Jerry Hue Truong Luong, Anahid Behrouzi

Architectural Engineering

To learn from past earthquake events, a critical task is validating observations with data. After a significant seismic event like the 2023 Kahramanmaras Türkiye earthquake series, various organizations perform reconnaissance efforts to collect building response data. Some reconnaissance missions focus on visiting fewer buildings and recording detailed information (high-resolution, HR), while others aim to visit as many buildings as possible recording basic information (low-resolution, LR). Both dataset types are vital for learning, and the next step is analyzing and visualizing the data to validate in-field observations. This paper has three purposes: 1) examine a HR dataset by Degenkolb with 138 …

Development Of An Undergraduate Course On Women In The Design Of The Built Environment, Anahid Behrouzi, Kira Hope Tolman, Paige Van Rossum

Architectural Engineering

The Cal Poly in San Luis Obispo (Cal Poly) Architectural Engineering (ARCE) department has seen significant progress in reaching gender equity as evidenced by recent student enrollment numbers. However, ARCE-affiliated technical and history classes still lack discussion of notable female practitioners or the value of input from women as project stakeholders. This educational shortcoming is likely true at many other civil or structural engineering, construction management, and architecture programs. To address this gap, the authors developed a new 1-credit hour course offered in Spring 2024 to Cal Poly Honors and ARCE students to expose them to the contributions and concerns …

Increasing Drift Capacity Of Non-Ductile Concrete Shear Walls Through Confinement With Fiber-Reinforced Polymer Application, Andrew Duong, Sophia Maglabe, Sheyna Rongong, Peter Laursen, Andrew Kline, Anahid Behrouzi

Architectural Engineering

The seismic response and laboratory testing of pre-1980s reinforced concrete (RC) shear walls commonly exhibit undesirable concrete crushing and rebar buckling in the wall end-zones leading to a flexural compressive failure. The lack of ductility of these walls is attributed to low reinforcement ratios and absence of special boundary elements (SBE) as required by modern design code. Thus, the authors are proposing a fiber reinforced polymer (FRP) retrofit method to provide confinement to the end-zones of pre-1980s walls equivalent to that of an SBE.

Current industry applications of FRP have largely been for shear strengthening of RC beams, columns, and …

The Impact Of Outdoor Thermal Comfort On Users’ Walkability: Case Study In Al Ain Square, Al Ain City, Uae, Alyazia Saeed Alnehayan

Thesis/ Dissertation Defenses

Living in a hot dry arid climate limits the walkability of its inhabitants. The excessive heat and dryness of the weather undoubtedly make walking a less tempting, encouraging, and pleasant choice for getting around the city. For that reason, this master thesis analyzes the various strategies used to enhance outdoor thermal comfort. Outdoor thermal comfort is controlled by numerous factors, including street and building orientation, vegetation, shading devices, and water bodies. The purpose of this study is to examine the relationship between walkability and UTCI values (universal thermal comfort index) in the context of Al Ain Square, a neighborhood in …

Rotational Rheometry Test Of Portland Cement-Based Materials – A Systematic Literature Review, Laura Silvestro, Artur Spat Ruviaro, Geannina Lima, Luís Urbano Durlo Tambara Júnior, Dimitri Feys, Ana Paula Kirchheim

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This Study Systematically Reviews 62 Papers on the Use of Rotational Rheometry to Assess the Fresh State Behavior of Portland Cement-Based Materials. the Research Highlights the Wide Variation in Test Methods and Aims to Provide a Comprehensive overview. Findings Reveal that 50.0% of Studies Employed Vane Geometry, despite its Limitations in Providing Transformation Equations. Regarding Dynamic Shearing Tests, 67.0% Followed a Consensus using a Pre-Shearing Step and a Stepwise Routine with Stabilization Times ≥ 10 S. While the Bingham Model is Commonly Used, the Study Emphasizes the Importance of Considering Shear-Thinning Behavior in Cementitious Materials. Models Like Herschel-Bulkley and Modified …

Sustainable Sensing With Paper Microfluidics: Applications In Health, Environment, And Food Safety, Sanjay Kumar, Jyoti B. Kaushal, Heow Pueh Lee

Durham School of Architectural Engineering and Construction: Faculty Publications

This manuscript offers a concise overview of paper microfluidics, emphasizing its sustainable sensing applications in healthcare, environmental monitoring, and food safety. Researchers have developed innovative sensing platforms for detecting pathogens, pollutants, and contaminants by leveraging the paper’s unique properties, such as biodegradability and affordability. These portable, low-cost sensors facilitate rapid diagnostics and on-site analysis, making them invaluable tools for resource-limited settings. This review discusses the fabrication techniques, principles, and applications of paper microfluidics, showcasing its potential to address pressing challenges and enhance human health and environmental sustainability.

3d Printing Of Fiber-Reinforced Calcined Clay-Limestone-Based Cementitious Materials: From Mixture Design To Printability Evaluation, Haodao Li, Jingjie Wei, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Sustainability and limitations in embedded reinforcement are the main obstacles in digital fabrication with concrete. This study proposed a 3D printable fiber-reinforced calcined clay-limestone-based cementitious material (FR-LC3). The binder systems incorporating calcined clay (CC) and limestone filler (LF) were optimized by determining the flow characteristics and water retention ability of the paste. The effect of fiber volume on the key fresh and mechanical properties of the fiber-reinforced mortars made with the optimized binder was evaluated. A combination of offline assessments and inline printing were employed to investigate the printability of the FR-LC3 with various binder systems and viscosity-modifying admixture (VMA) …

Design With, Not For, Local Community: Utilizing E- Participation Tools In The Design Of Socially Sustainable Vertical Emirati Public Housing, Omar Sherzad Shareef

Theses

Few years ago, local and federal governments in the UAE started to design and develop vertical public housing for Emirati residents as a new public housing typology that is believed to be more environmentally sustainable. Dibba Al-Hisn Housing Scheme in Sharjah and Al-Ghurfa Project in Al-Fujairah, are two recently developed vertical Emirati public housing projects developed by Sharjah Housing Directorate and Sheikh Zayed Housing Program (SZHP) respectively. Both projects, have been professionally designed, however, the residents’ opinions were not considered in the design process. Therefore, the main objective of this research is to explore the potentials of utilizing the advanced …

The Impact Of Outdoor Thermal Comfort On Users’ Walkability: Study Case In Al Ain Square, Al Ain City, Uae, Alyazia Saeed Alnehayan

Theses

Living in a hot dry arid climate limits the walkability of its inhabitants. The excessive heat and dryness of the weather undoubtedly make walking a less tempting, encouraging, and pleasant choice for getting around the city. For that reason, this master thesis analyzes the various strategies used to enhance outdoor thermal comfort. Outdoor thermal comfort is controlled by numerous factors, including street and building orientation, vegetation, shading devices, and water bodies. The purpose of this study is to examine the relationship between walkability and UTCI values (universal thermal comfort index) in the context of Al Ain Square, a neighborhood in …