Architectural Engineering Commons^™

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 …

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 …

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 …

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 …

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) …

Application Of Multidisciplinary Community Resilience Modeling To Reduce Disaster Risk: Building Back Better, Wanting "Lisa" Wang, John W. Van De Lindt, Blythe Johnston, P. Shane Crawford, Guirong Grace Yan, Thang Dao, Trung Do, Katie Skakel, Mojtaba Harati, Tu Nguyen, Robinson Umeike, Silvana Croope, Andre R. Barbosa

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

From december 10 to december 11, 2021, a deadly tornado outbreak struck across several states in the us, including arkansas, illinois, kentucky, and tennessee. This tornado outbreak resulted in at least $3.9 Billion in damage, more than 90 fatalities, and hundreds of injuries. Mayfield, kentucky, a small city in the eastern united states, was hit by a long-track tornado rated as an enhanced fujita 4 (ef4) scale and was one of the communities most heavily damaged during the tornado outbreak. Following the 2021 tornado event, an analysis was performed in the interdependent networked community resilience modeling environment (in-core) for the …

Cardboard Concrete Column Formwork, Danny Shrestha, Joelle Schalesky

Architectural Engineering

This project is an exploration of cardboard as a potential material for construction formwork for concrete columns. Multiple material tests were conducted to explore the behavior of cardboard and concrete. Multiple specimens of cardboard were tested for modulus of elasticity, moment of inertia, and tensile strength. Concrete was tested for its apparent lateral fluid pressure under vibration. Cardboard formwork was then designed and constructed based on these tested behaviors. The final design of the formwork consisted of folding cardboard sheets lined with hardboard, supported by wood studs, and tied by plastic banding straps.

Ultimately, two concrete columns―8' and 10' in …

Ace Mentor Program - Central Coast Chapter, Brayden Samuel Groshart

Construction Management

For my senior project, I established a chapter of the ACE (Architecture, Construction, and Engineering) Mentor Program in San Luis Obispo, California. This program provides high school students with hands-on experience and exposure to careers in the architecture, construction, and engineering industries. The program spanned eight weeks, balancing theoretical knowledge and practical application. The curriculum began with sessions on the fundamentals of architecture, engineering, and construction. In order to expose the students to real world practices, we organized tours of an architecture firm, an engineering firm, and an active construction site. These visits allowed students to engage with professionals, observe …

Construction Of Lightly Reinforced Concrete Shear Wall And Footings, Luke Jackson Method

Construction Management

This paper details the construction of two cast in place foundations as well as a lightly reinforced cast in place wall. The project, located inside the high bay, provides the Architectural Engineering (ARCE) department with an opportunity to test Fiber Reinforced Polymer wrap as a retrofitting option for walls dating back to pre-1980s. Due to site conditions, and project design, this project required extensive planning and communication within our team, faculty advisors, and shop technicians. This paper will discuss the phasing of construction and procurement of material that was required for the completion of this project. It also aims to …

Son Care Foundation – Lean To Shade Structure Design And Construction, Ryan Joseph Mccann

Construction Management

This paper discusses the design and construction of a lean-to-shade structure built for the Son Care Foundation in San Luis Obispo. The Son Care Foundation is a nonprofit organization that raises guide dogs for veterans and first responders with PTSD. This shade structure is 16 feet long and 6 feet wide, its height slopes from 9 feet in the front down to 8 feet in the back creating a roof pitch of 2:12. The sheet metal roof also has an overhang of approximately 1 foot. As requested by the client, the shade structure was designed to fit the aesthetic of …

Restoration Of The Cantilever Deck In Poly Canyon, Calvin S. Morgan, Calvin P. Vigeant, Roger G. Biddle

Construction Management

This interdisciplinary project aims to restore the Cantilever Deck in the Experimental Structures Laboratory back to an operational condition. As of Spring 2023, the deck has fallen into a state of disrepair and has been deemed structurally unsound by the university. The structural disrepair is concentrated around the wooden beams underneath the deck, but the handrails and overall color of the assembly have also fallen to levels deemed undesirable. The Restoration will remedy all these issues as well as guarantee that our repairs will last long into the future. This project is an interdisciplinary effort, the team consists of ARCE …

Performance Of Co2-Cured Alkali-Activated Blast-Furnace Slag Incorporating Magnesium Oxide, Yubin Jun, Seong Ho Han, Jae Hong Kim

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigated characteristics of alkali-activated slags incorporating magnesium oxide (MgO) subjected to CO₂ curing. The samples were prepared by adding 2%, 5%, and 10% MgO to the total binder mass. The mixture was activated with potassium hydroxide (KOH) and cured in a CO₂ incubator for 3 days. The compressive strength of the MgO-incorporated CO₂-cured alkali-activated slag was higher than that of the conventional alkali-activated slag at all ages up to 28 days. No reduction in the strength was observed over time. The enhanced strength was independent of MgO content. Combined X-ray diffraction with thermogravimetric analysis …

Advancing Simultaneous Extraction And Sequential Single-Particle Icp-Ms Analysis For Metallic Nanoparticle Mixtures In Plant Tissues, Lei Xu, Xingmao Ma, John Yang, Joel G. Burken, Paul Ki-Souk Nam, Honglan Shi, Hu Yang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Engineered Nanoparticles (ENPs) Have Been Increasingly Used in Agricultural Operations, leading to an Urgent Need for Robust Methods to Analyze Co-Occurring ENPs in Plant Tissues. in Response, This Study Advanced the Simultaneous Extraction of Coexisting Silver, Cerium Oxide, and Copper Oxide ENPs in Lettuce Shoots and Roots using Macerozyme R-10 and Analyzed Them by Single-Particle Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Additionally, the Standard Stock Suspensions of the ENPs Were Stabilized with Citrate, and the Long-Term Stability (Up to 5 Months) Was Examined for the First Time. the Method Performance Results Displayed Satisfactory Accuracies and Precisions and Achieved Low Particle Concentration …

Chloride Binding Mechanism In Seawater-Mixed Uhpc, Wei Zhang, Dawei Ding, Mengmeng Li, Tiao Wang, Hongyan Ma, Binmeng Chen, Hongxing Hu, Jizhou Chen, Xiaomin Liu, Dongshuai Hou

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The rapid development of marine concrete structures and the sharp shortage of freshwater resources contribute to the wide investigation of seawater-mixed ultra-high-performance concrete (swuhpc). However, few studies have investigated the chloride ions (cl-) binding mechanism of swuhpc. Herein, the chloride binding experiments and molecular dynamics (md) simulation were carried out to reveal the physically and chemically bound cl- mechanisms of swuhpc. The results of the experiments clearly demonstrate that the addition of silica fume (sf) led to a significant decrease in the capacity of cl- binding. Conversely, the incorporation of metakaolin (mk) resulted in a marked increase in the content …

Raising The Green Roof: Enhancing Youth Water Literacy Through Built Environment Education, Laura B. Cole, Lilian Priscilla, Laura Zangori, Beth Kania-Gosche, Joel G. Burken

Teacher Education and Certification Faculty Research & Creative Works

Green Roofs Cool Cities, Clean the Air, Provide Habitat, and Manage Stormwater. They Are Compelling Tools to Teach Interconnected Human-Ecological Systems. This Study Included the Design, Pilot, and Evaluation of a Fourth-Grade Science Unit Entitled "Raising the Green Roof", Exploring These Connections. Five Classrooms in Two Midwestern U.S. Public Elementary Schools Participated, and 4th-Grade Students (N = 73) Drew Systems Models at Three Time Points (212 Models) and Wrote their Ideas. Qualitative Content Analyses of the Models Showed that Learners Were Increasingly Combining Social Systems (Green Roof Infrastructure) with Ecological Systems (Water Cycle) Across the Unit. Students Also Increasingly Evidenced …

Four-Way Cfd-Dem Coupling To Simulate Concrete Pipe Flow: Mechanism Of Formation Of Lubrication Layer, Tooran Tavangar, Masoud Hosseinpoor, Jeffrey S. Marshall, Ammar Yahia, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study introduced a four-way CFD-DEM coupling approach to simulate the shear-induced particle migration (SIPM) mechanism leading to formation of the lubrication layer (LL) during concrete pumping. The CFD-DEM simulations considered the coupled effect of concentration (10 %–40 %) and wide size distribution (1–17 mm) of aggregate and rheology of the mortar for forces between the suspending matrix and the particles (and vice versa), as well as force transmission directly between particles (and the pipe wall). The formation of the LL was successfully simulated through a more realistic understanding the SIPM mechanism and rheological evaluation across the pipe with comparable …

Surface Coating Method For Cement-Based Materials To Improve Chloride Ion Penetration Resistance Using Amine-Based Co2 Solvent, Seongho Han, Tae Hoon Han, Jae Hong Kim

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The application of coatings on concrete surfaces serves as a protective shield, guarding the structure against chlorides and averting corrosion of the reinforcement, consequently enhancing its durability. This study investigates the resistance of cement mortar samples to chloride ion penetration when coated with an amine-based carbon dioxide (CO2) solvent. Various factors, including monoethanolamine (MEA) concentrations of 1, 10, and 30 wt.%; water-to-cement ratios (w/cm) of 0.35, 0.4, and 0.5; coating timings on day 3 and day 27; and pre-conditioning methods such as air drying, are investigated for their impact on the performance of chloride penetration resistance. Specifically, pre-conditioning significantly enhanced …

A Review Of Whipple Shield Ballistic Limit Equations, S. Ryan, W. (William) P. Schonberg

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Ballistic limit equations (BLEs) are semi-analytical expressions used to predict the risk posed by micrometeoroid and orbital debris (MMOD) impacts on a spacecraft. A foundational BLE, known as the new non-optimum (NNO) equation was published by Eric Christiansen of NASA Johnson Space Center in 1990 for application on Whipple shields – two-plate configurations consisting of a thin sacrificial plate located at some standoff in front of the spacecraft pressure hull or structural wall. Today, BLEs for almost all multi-plate spacecraft structures, e.g., honeycomb sandwich panels, monolithic structures with thermal insulation blankets, etc., are based on the NNO Whipple BLE. We …

Using Virtual Reality Technologies In Built Environment Education, Rebekah Floyd, Kayla Walters, Stuart Werner Baur

Undergraduate Research Conference at Missouri S&T

Virtual reality (VR) offers transformative potential in built environment education, including human-made surroundings like buildings and infrastructure. This review explores VR's benefits, challenges, and trends in this field. VR fosters immersive learning, allowing students to explore architectural designs and urban planning scenarios. It provides hands-on experiences, enhancing spatial understanding and critical thinking. Simulations enable safe experimentation with design ideas and construction techniques without the real-life limitations or risk holding students back. However, challenges include high costs, technical limitations, and the need for educator training. Ensuring accessibility for all students is crucial. Despite challenges, VR's potential to revolutionize built environment education …

Analyzing The Viability Of Novel Reactor Technology, Auston Obsuth

Undergraduate Research Conference at Missouri S&T

This study explores an innovative anaerobic digestion reactor technology aimed at improving the sustainability and efficiency of organic waste management. By employing a system without mechanical parts, it seeks to significantly enhance energy conversion from waste, tackling waste accumulation and the need for renewable energy sources. The project will use a multidisciplinary approach, incorporating economics, engineering management, and environmental science, to thoroughly evaluate the reactor's performance in terms of gas production, stability, and efficiency. Additionally, it will assess the economic viability and environmental impact, emphasizing advantages such as waste reduction and decreased greenhouse gas emissions. Additionally, preliminary market analysis and …

Effects Of Rest Time And Curing Regime On Short- And Long-Term Strength Of Class C Fly Ash-Based Alkali-Activated Mortars, Cedric Kashosi, Ahmed Gheni, Eslam Gomaa, Mohamed Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigated how different rest times affect the strength development of fly-ash-based alkali-activated mortar (aam) over a period of 90 days. Two types of fly ash with varying calcium oxide contents of 37 and 21% were used. The rest times ranged from 2 to 36 h, and three curing methods (ambient, oven, and steam) were tested. The results showed that the rest time significantly influenced the compressive strength of the aam. The optimal rest time was found to be between 12 and 30 h depending on the curing method and fly ash type. Beyond this range, there were only …