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Human-Centered Approach For Resilience Assessment Of Healthcare Networks Subjected To Sequential Earthquakes, Emad Hassan, Hussam Mahmoud Nov 2024

Human-Centered Approach For Resilience Assessment Of Healthcare Networks Subjected To Sequential Earthquakes, Emad Hassan, Hussam Mahmoud

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Healthcare services are critical for community resilience and stability as their role after disastrous events is indispensable to reducing casualties and returning the community to normalcy. Sequential mainshock-aftershock events can damage hospital components, reduce utility availability, and cause multiple patient surges. No studies have been conducted to evaluate the impact of mainshock-aftershock events on healthcare resilience. Accordingly, here we investigate the impact of multiple earthquakes on the healthcare network in Shelby County, Tennessee, and determine the optimal resources needed to enhance its functionality. The functionality is estimated by combining functionality quantity and quality terms. The quantity is calculated based on …


Pozzolanic Reactivity Of Carbonated High-Calcium Fly Ash: A Mechanism Study, Gao Deng, Nannan Zhang, Wenyu Liao, Hongyan Ma, Yongjia He, Linnu Lu, Lingyu Chi Oct 2024

Pozzolanic Reactivity Of Carbonated High-Calcium Fly Ash: A Mechanism Study, Gao Deng, Nannan Zhang, Wenyu Liao, Hongyan Ma, Yongjia He, Linnu Lu, Lingyu Chi

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This research investigates the impact of accelerated carbonation treatment on the pozzolanic reactivity of high-calcium fly ash (HFA) by monitoring the reaction heat of HFA/carbonated HFA (CFA)-calcium hydroxide (CH) blends and elucidates the underlying factors influencing the pozzolanic reactivity. The results indicate that in HFA/CFA-CH blends, CFA exhibits a comparable pozzolanic reactivity to that of HFA. This is attributed to the carbonation products accelerating the formation of MonoCarb aluminate (main) and C-S-H, compensating for the reduced heat resulting from the diminished highly reactive components after the carbonation treatment. Additionally, the increased surface area due to carbonation treatment is favorable for …


Common Ground Newsletter Fall 2024, Missouri University Of Science And Technology Sep 2024

Common Ground Newsletter Fall 2024, Missouri University Of Science And Technology

Common Ground

-Internship Experiences

-Lady Softball Trio

-Summer Camps

-Design Teams


Reduction In Scc Form Pressure Through In-Situ Co2 Mineralization, Sean Monkman, Soo Duck Hwang, Kamal Khayat Sep 2024

Reduction In Scc Form Pressure Through In-Situ Co2 Mineralization, Sean Monkman, Soo Duck Hwang, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

One challenge of using self-consolidating concrete (SCC) for cast-in-place structural applications is that the rheological properties of the concrete (low yield stress and low plastic viscosity) can lead to increased lateral pressure exerted on the formwork. High structural build up and thixotropy can reduce the lateral pressure, thereby allowing for simpler formwork and faster construction. The addition of CO2 to SCC, in proportions from 0.063 % to 0.250 %, by weight of cement, was investigated as a rheology modifier. The CO2 served to increase the plastic viscosity with little impact on the dynamic yield stress up to a …


Molecular Dynamics Simulation Insights Into Rejuvenating Aged Asphalt With Waste Soybean Oil And Polymers, Ke Shi, Feng Ma, Zhen Fu, Jenny Liu, Ruimeng Song, Dongdong Yuan, Yujie Tang Aug 2024

Molecular Dynamics Simulation Insights Into Rejuvenating Aged Asphalt With Waste Soybean Oil And Polymers, Ke Shi, Feng Ma, Zhen Fu, Jenny Liu, Ruimeng Song, Dongdong Yuan, Yujie Tang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study utilized molecular dynamics simulations to assess the rejuvenation of aged asphalt (AA) with waste soybean oil (WSO) and functionalized SBS polymers, focusing on: 1) constructing and validating models for virgin asphalt (VA), AA, and composite rejuvenated asphalt with WSO and polymers; 2) analyzing diffusion effects and binding abilities in these rejuvenated models; 3) evaluating interface binding and diffusion behaviors in composite rejuvenated models. The addition of functionalized SBS molecules and WSO improved the diffusion rates of various components within these models. Specifically, functionalized linear-SBS (LSBS) molecules demonstrated superior diffusion performance compared to star-SBS (SSBS) molecules. Incorporating WSO and …


Investigation Of The Cohesive Behavior Of Water-Intervened Rejuvenated Sbs-Modified Bitumen, Ke Shi, Feng Ma, Zhen Fu, Jenny Liu, Ruimeng Song, Dongdong Yuan, Yujie Tang Aug 2024

Investigation Of The Cohesive Behavior Of Water-Intervened Rejuvenated Sbs-Modified Bitumen, Ke Shi, Feng Ma, Zhen Fu, Jenny Liu, Ruimeng Song, Dongdong Yuan, Yujie Tang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

When water interacts with bitumen, the diffusion and cohesion characteristics between the components of bitumen are negatively impacted. Molecular dynamics simulations were employed to construct various bitumen models, including bitumen–bitumen (without water), water-containing single bitumen, water-containing bitumen–bitumen, and bitumen–water–bitumen models. The primary research objectives were as follows: comparing the changes in the densities of bitumen models with and without water, analyzing the interlayer cohesive energies of bitumen models interacting with water, evaluating the hydrogen bonds in water-containing bitumen models, and characterizing the diffusion behaviors of bitumen components. The results indicated that when water interacted with the bitumen, it filled internal …


Effect Of Superabsorbent Polymer On 3d Printing Characteristics As Rheology-Modified Agent, Yu Cun Gu, Kamal H. Khayat Aug 2024

Effect Of Superabsorbent Polymer On 3d Printing Characteristics As Rheology-Modified Agent, Yu Cun Gu, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study aims to investigate the effects of two superabsorbent polymer (SAP) types, S1 and S2 (with continual absorption and rapid desorption, respectively) as rheology-modified agent on 3D printing characteristics. Three base mixtures were selected with different thixotropic behaviors (i.e., mixtures with high re-flocculation (τfloc), high structuration rate (Athix), and both low τfloc and Athix, respectively). The initial mini-slump flow of 190±10 mm was secured by adjusting superplasticizer (SP) or water demand (increasing w/b by either 0.025 or 0.05). An extrudable region was determined within the range of τfloc (200-890 Pa) and Athix (15-60 Pa/min). The use of the S2 …


Coupled Effect Of Fiber Type And Reinforcement Ratio On Flexural Behavior Of Reinforced Beams Cast With Super Workable Concrete, Jingjie Wei, Le Teng, Kamal H. Khayat Aug 2024

Coupled Effect Of Fiber Type And Reinforcement Ratio On Flexural Behavior Of Reinforced Beams Cast With Super Workable Concrete, Jingjie Wei, Le Teng, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigated the effect of 5-dimensional hooked-end fiber (5D) on the structural performance of beams and compared its efficiency with other fibers in strengthening structural performance of reinforced concrete (RC) beams with an increase in reinforcement ratio (ρ). The potential of using fibers to reduce the longitudinal rebar based on various design criteria was investigated. The fibers included 5D, a combination of 80 % 3-dimensional hooked-end and 20 % short steel fibers (STST), and two combinations of macro synthetic fibers A and B (MSF). Experimental results indicated that, compared to non-fibrous beams, using 5D was the most efficient in …


Extrudability Window And Offline Test Methods To Predict Buildability Of 3d Printing Concrete, Yu Cun Gu, Kamal H. Khayat Aug 2024

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 Aug 2024

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 …


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 Aug 2024

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 …


Indefinability Of Effective Stress For Unsaturated Soils, Xiong Zhang, Sandra Houston Aug 2024

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 …


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 Aug 2024

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 …


Development Of Multivariate-Coupled Grouting Diffusion Model For Rcc, Xiao Sun, Yao Wang, Hengrui Liu, Zhuanjia Yang, Hongyan Ma Jul 2024

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 …


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 Jul 2024

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 …


Freezing-Thawing Hysteretic Behavior Of Soils, Jidong Teng, Antai Dong, Sheng Zhang, Xiong Zhang, Daichao Sheng Jul 2024

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 Jun 2024

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 …


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 Jun 2024

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 …


3d Printing Of Fiber-Reinforced Calcined Clay-Limestone-Based Cementitious Materials: From Mixture Design To Printability Evaluation, Haodao Li, Jingjie Wei, Kamal H. Khayat Jun 2024

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) …


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 May 2024

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 May 2024

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 May 2024

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 …


A Review Of Whipple Shield Ballistic Limit Equations, S. Ryan, W. (William) P. Schonberg May 2024

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 …


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 May 2024

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 …


Analyzing The Viability Of Novel Reactor Technology, Auston Obsuth Apr 2024

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 …


Using Virtual Reality Technologies In Built Environment Education, Rebekah Floyd, Kayla Walters, Stuart Werner Baur Apr 2024

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 …


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 Apr 2024

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 …


Feature Engineering And Supervised Machine Learning To Forecast Biogas Production During Municipal Anaerobic Co-Digestion, Hunter W. Schroer, Craig L. Just Mar 2024

Feature Engineering And Supervised Machine Learning To Forecast Biogas Production During Municipal Anaerobic Co-Digestion, Hunter W. Schroer, Craig L. Just

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Municipalities with excess anaerobic digestion capacity accept offsite wastes for co-digestion to meet sustainability goals and create more biogas. Despite the benefits inherent to co-digestion, the temporal and compositional heterogeneity of external waste streams creates operational challenges that lead to upsets or conservative co-digestion. Given the complex microbial bioprocesses occurring during anaerobic digestion, prediction and modeling of the outcomes can be challenging, and machine learning has the potential to improve understanding and control of co-digestion processes. Biogas flows are a surrogate for process health, and here, we predicted biogas production from historical data collected by a water resource recovery facility …


Characterizing Chemistry And Microbiomes During Continuous Anaerobic Codigestion Of Organics And Cattle Manure Digestate, Emily V. Schmitz, Hunter W. Schroer, Timothy E. Mattes, Craig L. Just Mar 2024

Characterizing Chemistry And Microbiomes During Continuous Anaerobic Codigestion Of Organics And Cattle Manure Digestate, Emily V. Schmitz, Hunter W. Schroer, Timothy E. Mattes, Craig L. Just

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

We characterized chemical and microbial responses to changes in the carbon-to-nitrogen ratio (C:N) and organic loading rate (OLR) during anaerobic codigestion (ACoD) of cattle manure digestate mixed with industrial organics. C:Ns of 25 and 35, both operating at OLRs ≤ 4 gVS L-1 d-1, sustained methane production averages of 0.36 ± 0.03 L gVS-1 d-1 and 0.32 ± 0.05 L gVS-1 d-1, respectively, throughout a 15-day period. Using 16S rRNA high-throughput sequencing coupled with PICRUSt2, taxonomy and predicted gene abundances were mapped to the major ACoD stages. C:N (25, 35) and the OLR (2, 4 gVS L-1 d-1) had minimal …


Methodology To Design Eco-Friendly Fiber-Reinforced Concrete For 3d Printing, Haodao Li, Alfred Addai-Nimoh, Eric Kreiger, Kamal H. Khayat Mar 2024

Methodology To Design Eco-Friendly Fiber-Reinforced Concrete For 3d Printing, Haodao Li, Alfred Addai-Nimoh, Eric Kreiger, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Greater use of locally available supplementary cementitious materials (SCM) to reduce cement content and addition of fiber reinforcement can enhance the performance of 3D printing (3DP) technology in construction. In this study, three classes of eco-friendly 3D printable fiber-reinforced mixtures were targeted, namely ultra-high-performance concrete (UHPC), high-performance concrete (HPC), and conventional concrete (CC). A step-by-step methodology was proposed to maximize the substitution rate of cement with SCM and limestone filler and optimize fiber volume for the successful development of 3D printable fiber-reinforced materials. Binder combinations were initially investigated on the paste level to determine the packing density and robustness. Selected …