Engineering Commons^™

A Thermo-Mechanical Analysis Of The Well-Structure Integrity In Enhanced Geothermal Systems Using Numerical Simulation, John Alfred Ganal Acevedo

Theses and Dissertations

This thesis will investigate the well structure integrity of enhanced geothermal systems. Enhanced geothermal system is a type of renewable energy generation that utilizes heat from a rock reservoir deep within the Earth’s subsurface delivered by circulating working fluids through kilometers-long well structures. However, due to the surrounding environment and harsh operating conditions, the well structures are vulnerable to deterioration and cracking, which can lead to structural failure of wells and reduced energy efficiency. The study seeks to gain a better understanding of the vulnerability of the well structure. A finite element model of a well structure was developed, and …

Degradation Products And Microbial Communities Associated With The Conversion Of Five Long-Chain Fatty Acids Relevant For Anaerobic Co-Digestion Of Fog With Sludge, Claire Funk

All Theses

Anaerobic digestion is a technology that allows wastewater treatment plants to convert sludge to energy by recovering the biogas produced during the breakdown of proteins, carbohydrates, and lipids. Furthermore, adding fats, oils, and greases (FOG) through co-digestion with wastewater sludge can increase energy production as lipids have a higher methane yield than proteins and carbohydrates. However, adding FOG can also lead to operational problems in the digester due to the potential accumulation of certain long-chain fatty acids (LCFAs). Current research is limiting in the degradation pathways of prominent LCFAs in FOG and the microbial communities responsible for their degradation

The …

Proportioning And Performance Of Ultra-High Performance Concrete (Uhpc) For High Friction Surface Treatment (Hfst) On Pavement And Bridge Decks, Adam R. Biehl

All Theses

High Friction Surface Treatment (HFST) is a roadway remediation technique used to improve pavement’s coefficient of friction, to enhance roadway safety. The application of HFSTs has repeatedly demonstrated the ability to significantly reduce crashes in both wet and dry conditions. Typically, epoxy-resins and calcined bauxite aggregate are used in HFST treatment. However, the high material costs and scarcity of calcined bauxite render this form of HFST an expensive and limited option for roadway rehabilitation. Therefore, the identification of alternative binders and HFST aggregates is needed for broad scale implementation. One potential alternative binder is Ultra-High-Performance Concrete (UHPC), a specialty cementitious …

Advancing Unmanned Ground Vehicle Path Planning With Quantified Map Uncertainty, Israel Afriyie

All Theses

This thesis addresses the complex challenge of path planning for Unmanned Ground Vehicles (UGVs) in areas where traditional navigation systems are inadequate, such as unstructured or off-road military zones. Recognizing the limitations of current path planning algorithms, which primarily focus on optimizing for the shortest path and often fail to account for variability and risks, this research proposes an enhanced Hyperstar algorithm. This approach not only considers the fastest route but also integrates maximum delays and visibility risks into its computation, ensuring a balance between swift mission completion and concealment from adversaries.

Utilizing terrain maps and incorporating uncertainties in map …

Ultra High-Performance Concrete As A High Friction Surface Treatment For Pavements And Bridges, Kyle Maeger

All Dissertations

High Friction Surface Treatment (HFST) is a proven technology to reduce crashes on roadways by increasing the coefficient of friction between vehicle tires and the pavement. However, it is an expensive solution due to the high cost of the two commonly used constituent materials, calcined bauxite aggregate and epoxy resin binders.

This study evaluated the abrasion resistance performance of four alternative HFST aggregates to calcined bauxite using Los Angeles Abrasion and Micro-Deval Abrasion tests, and studied the surface texture utilizing a high-resolution laser scanner and friction utilizing the British Pendulum Test.

This study also assessed the performance of non-proprietary Ultra …

Base Case Shear-Wave Velocity Profiles And Non-Linear Material Property Models Of Local Site Conditions In South Carolina For Seismic Site Response Analyses, Ali Sedaghat Shirehjini

All Dissertations

This dissertation presents the development of base case small-strain shear-wave velocity ( ) profiles and non-linear materials property models of local site conditions in South Carolina for seismic site response analyses. The need to address South Carolina's seismic hazards is partly motivated by the 1886 Charleston earthquake (moment magnitude, M_w= 6.7 to 7.5). Required inputs for seismic site response analysis include profile down to a specified reference outcrop condition and non-linear material properties for each layer in the profile. Although firm rock (i.e., ≥ 2,500 ft/s) or hard rock (i.e., ≥ 9,850 ft/s) is commonly assumed for the …

An Emergency Response System To Assist The Movement Of Vehicles During Emergency Operations In Urban Transportation Networks, Jamal Nahofti Kohneh

All Dissertations

Emergency responders need to arrive at the emergency scene as soon as possible, but operating vehicles under emergency conditions can pose a risk to both the responders and other road users, potentially resulting in crashes or delays in emergency operations. In this research, an emergency response system is proposed to assist emergency and non-emergency response vehicles (ERVs and non-ERVs) during emergency operations in a connected vehicle environment. This system collects the information from connected ERVs and non-ERVs, utilizes this information as inputs in the proposed models, and sends instruction messages back to vehicles. The proposed models provide the fastest ERV …

Improving The Long-Term Maintenance And Durability Of Pervious Concrete Pavements, Kate Elizabeth Christiansen

All Graduate Theses and Dissertations, Fall 2023 to Present

Impervious concrete is constructed for most new infrastructure such as housing developments, commercial projects, and industrial facilities, which prevents stormwater runoff from infiltrating into groundwater storage. Pervious concrete is a sustainable, economical, and safe alternative to collect runoff and prevent the issues resulting from increased land development.

Although pervious concrete has the benefit of a large porous structure for water infiltration, this high porosity leads to issues with debris, sand, and other materials clogging the porous areas. Pervious concrete also has the challenge of non-standardized material preparation techniques, testing, and construction practices. As such, more research is needed to improve …

Method Development For The Extraction And Analysis Of Per- And Polyfluoroalkyl Substances (Pfas) In Wastewater And Biosolids, Victoria Krull

All Graduate Theses and Dissertations, Fall 2023 to Present

Per and poly-fluorinated alkyl substances (PFAS) are manufactured chemicals that have water and grease repellant properties and do not readily biodegrade. PFAS are present in many consumer products and end up in waste systems and the environment. Studies have shown that PFAS can have adverse health effects on humans and animals.

There are many challenges to processing and analyzing samples containing PFAS including: adsorption of PFAS to equipment, contamination from equipment containing PFAS, and the high sensitivity needed to analyze for PFAS in the parts per trillion detection range. The United States Environmental Protection Agency (EPA) has been developing methods …

Application Of Electrical Impedance Tomography To Cementitious Composites, Hugo Zazueta

Theses and Dissertations

This thesis explores the feasibility of using Electrical Impedance Tomography (EIT) for detecting damage in cementitious composites. Cementitious composites, such as concrete and cement mortar, are insulating; any conductive properties arise from the moisture within their pores and capillary structures. The proposed concept herein is that formed internal damages in cementitious composites consequently alter their pore and capillary structure, which can then be detected through EIT imaging. To construct tomographic images, the Gaussian Newton (GN) reconstruction algorithm, enhanced with priors, was employed. The results were then compared across different reconstruction processes. Cylindrical cement pastes and cement mortar samples were prepared, …

Trip Production Models For Persons With Disabilities, Pouyan Saeidian

All Graduate Theses and Dissertations, Fall 2023 to Present

Nearly 13% of the US population consists of people with disabilities, yet finding an equitable and comprehensive approach to meet their travel needs remains a challenge. Our research delves into the mobility patterns of people with disabilities to understand how their daily travel—both the frequency of trips and the distance covered—compares to those without disabilities. We also explore the factors influencing their travel behaviors and how these insights can guide policymakers in improving accessibility and mobility for this community. Utilizing data from the 2022 US National Household Travel Survey, we applied a blend of statistical analysis and machine learning methods. …

Evaluation Of Unreinforced And Geosynthetic-Reinforced Subgrade Material Performance With Large-Scale Tracking Wheel Tests And Dynamic Cone Penetrometer Tests, Kenaz Owusu

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Subgrade has a significant impact on the performance of a pavement as it serves as the foundation layer on which traffic loads are transferred. Many pavement failures can be attributed to weak subgrade strength. The integration of geosynthetics in road pavements has been identified as an effective solution for enhancing subgrade performance to withstand imposed traffic. This study evaluated the performance of unreinforced and geosynthetic-reinforced subgrades in Nebraska to quantify the contribution of geosynthetics to unpaved layer systems.

The strength and stiffness of different soil subgrades were assessed through unconfined compressive strength tests and repeated load triaxial (RLT) tests, which …

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. …

Investigating Productivity Of Modular Buildings, Sibgat Mehedi Hasan

UNLV Theses, Dissertations, Professional Papers, and Capstones

The modular construction industry has grown substantially, yet understanding of the relationships between project categories, sizes, and productivity remains limited. This study investigates these relationships in both permanent and relocatable modular construction projects across different sectors, including multifamily housing, dormitories, healthcare, education, retail, office, and workforce housing. Data from 303 permanent and 188 relocatable projects in the Modular Building Institute database were analyzed using Kendall's tau-b correlation and linear regression analyses. Key findings reveal that permanent projects outnumber and are generally larger than relocatable ones, with education being the most common project type. Significant positive correlations between project size and …

Evaluation Of Manual Thermal Brake Screening Systems, Jeeyen Koo, David Leddy, Jennifer Walton

Kentucky Transportation Center Research Report

In 2021, manual thermal brake screening systems were installed at Lyon EB and Rowan County weigh stations. Two additional units were installed at Laurel SB and Scott County weigh stations the following year. Although this system is called a thermal brake screening system, its thermal camera images are used to find both brake and tire-related violations. At the time of this project, Lyon (EB), Rowan, and Scott County inspection locations also had tire pressure detection systems in addition to manual thermal brake screening systems. Both systems can be used to identify tire-related violations, but inspectors prefer to use the tire …

Development Of A Turning Movement Estimator, Somayeh Nazari Enjedani

Boise State University Theses and Dissertations

Turning Movement (TM) counts at intersections are crucial for several reasons. There has been extensive research on this topic throughout the history of traffic research, which reflects its importance in transportation engineering and urban planning. It can be said that one of the most significant applications of TMs is signal timing at intersections. Signal timing design requires data on the turning decisions of vehicles that travel through intersections to allow enough time for each movement at the intersection. Most of organizations around the USA are still applying traditional methods for collecting TM data, such as manual counts. These methods are …

Time-To-Failure Prediction Of Fine-Grained Soil Slopes Subject To Weather-Driven Deterioration, Arm M. Morsy

Mineta Transportation Institute

Embankments have been widely used in the construction of transportation and flood defense infrastructure. Embankments constructed from clays experience a suite of weather-driven deterioration processes that lead to a progressive loss of hydromechanical performance, causing potentially severe and costly consequences. This study aimed to predict the time to failure of aging, deteriorating clay embankments supporting transportation infrastructure. A multi-phase numerical modeling approach was developed to replicate the long-term, weather-driven, hydromechanical behavior of clay embankments. This model simulated the behavior of a number of well-documented embankment failure case studies that had sufficient data to derive the necessary soil properties and climate …

Quantifying Lock Criticality For Inland Waterway Navigation Using An Agent-Based Simulation, Ashwin Narayan

Industrial Engineering Undergraduate Honors Theses

Inland waterway travel has tremendous potential to improve multimodal transportation in the United States due to its environment-friendly and safe nature. Waterway travel has proven to be much cheaper per ton-mile and more fuel efficient than trucks. Millions of dollars have recently been invested in inland waterway networks to facilitate travel. The waterway infrastructure must be resilient to enable efficient waterway travel and prevent unnecessary delays. Locks, an important component of waterway infrastructure, enable vessels to travel between waterways of varying depths and must be maintained consistently to avoid unexpected failures. However, with limited resources, it is difficult to preserve …

Analysis Of The Relationship Between Speed Consistency And Traffic Accident Probability (On The Mojokerto-Surabaya Toll Road), Riki Risfiandi, Martha Leni Siregar

Smart City

Vehicle speed consistency plays a crucial role in maintaining traffic safety, with speed limits set to reduce accident fatalities. While the direct impact of speed limits on vehicle speed is minimal, their implementation significantly influences driver behavior, with about 85% of drivers complying with speed limits. However, variables such as traffic volume, weather conditions, and travel urgency often cause drivers to be inconsistent in adhering to these limits, increasing accident risk. On the Mojokerto-Surabaya toll road, data from Traffic Corps and Jasa Marga recorded 193 accidents with 101 fatalities from 2018 to August 2023, mostly caused by driver behavior such …

Road To Sustainability: Developing A Sustainability Performance Measurement Framework For City Logistics From A Multi-Stakeholder Perspective, Xu Zhang

Doctoral

Sustainability assessment in city logistics has been a perpetual and salient agenda among city managers and logistics industry practitioners, especially in light of the promotion of the new Corporate Sustainability Reporting Directive (CSRD) and European Sustainability Reporting Standards (ESRS). Research studies to date have tried to assess city logistics operations’ sustainability performance and their impact, but most endeavours have ended in vain due to elusive sustainability goals, inconsistent indicator quality, ambiguous stakeholder responsibility, and poor data availability on city levels.

To address these challenges, this study is advocating for a collaborative sustainability reporting and assessment process among public and private …

Effect Of Aging Temperature On Properties Of Sealant Under Field Construction Conditions, Liu Hanchao, Teng Xinhua, Zhang Jingyan, Zhang Kaihua, Lin Hui

Journal of China & Foreign Highway

In order to study the influence of short-term aging temperature on the properties of sealant,a sealant was prepared,and field construction conditions were simulated.The properties of the sealant before and after short-term aging at 180‒220 ℃ were tested.The viscoelastic properties,physicochemical properties,and microstructures of the sealant were studied,and the mechanism of property changes was discussed.The results show that the cone penetration and flow value of the aged sealant decrease,while the softening point and elastic recovery rate increase.Aging at high temperature (>180 ℃) for a short time and low temperature (160 ℃) for a long time will cause obvious property changes.The tensile …

Experimental Study On Capillary Water‑Holding Characteristics Of Loess Backfill In Ecological Ditches, Nan Yalin, Zhang Xiaoyu, Chen Hong, An Peng, Liu Kui, Camara Ibrahima Kalil

Journal of China & Foreign Highway

The municipal ecological ditches have the basic functions of accumulating water for infiltration in the rainy season and conserving moisture in the dry season.However，the design of loess backfill in ecological ditches is based on no evidence，which often leads to landscape vegetation drowning in the rainy season or dying in the dry season.For this reason，a study was carried out by remoulding loess with a small-size capillary water rise height test，a large-size water-holding characteristic model test，and an unsaturated numerical analysis.The results show that the final capillary water rise height of the soil column can reach 100 cm when the dry density is …

Research On Performance Of Coal Gangue Concrete, Wang Jiliang, Ma Wenhui, Xu Weidong, Lyu Zhigang

Journal of China & Foreign Highway

Coal gangue is an industrial solid waste produced in the process of raw coal mining.It has a large stock and a relatively low utilization rate.Using coal gangue as concrete aggregate can not only solve the environmental pollution caused by coal gangue storage but also make up for the shortage of natural sand and gravel resources，which opens up an effective way for the large-scale utilization of coal gangue.According to the application characteristics of coal gangue as concrete aggregate，the chemical component，mineral composition，and physical properties of coal gangue were systematically analyzed.The influence of coal gangue as aggregate on the working performance，mechanical properties，volume stability，and …

Experimental Study On Shear Performance Of Uhpc‑Nc Interface, Wan Zhiyong, Chen Jianping, He Shaohua, Huang Xu, Sun Xiangdong

Journal of China & Foreign Highway

Ultra-high performance concrete （UHPC） has great application prospects in engineering structure reinforcement.The reliability of the bonding properties at the interface between the new UHPC reinforcement layer and the old concrete structure is critical for ensuring the serviceability of the reinforced structures.To determine the influence of different interface treatments on the bonding properties at the interface between the UHPC and normal concrete （NC），six Z-shaped UHPC-NC bonding specimens were designed，and the bonding properties of the UHPC-NC with three different kinds of interface，namely smooth，chisel，chisel + reinforced，were investigated.In addition，nonlinear finite element models for the concrete interface were established to determine the distribution law of …

Application Of Sequential Quadratic Programming Method In Cable Force Adjustment Of Cable‑Stayed Bridges, Xu Yufeng, Zhu Mengyang, Chen Si, Xie Yunfei

Journal of China & Foreign Highway

When the construction of a cable-stayed bridge enters the completion stage，due to various factors，there is a certain error between the actual alignment and internal force of the structure and the theoretical completion state，and it is usually necessary to adjust the cable force.In order to calculate the cable force adjustment of a cable-stayed bridge in the adjustment stage，a method based on an influence matrix and sequential quadratic programming was proposed to solve the cable force adjustment.A large-span hybrid girder cable-stayed bridge was taken as the background，and the alignment and internal force response values of the structure with varying cable units were …

Protection Design Of Middle Piers Of Overpass Bridges Based On Double Protection Concept, Lyu Sizhong, Wang Xin, Guo Jianmin, Liu Siyuan, Li Yuxin, Yang Fuyu

Journal of China & Foreign Highway

The collision accident types of middle piers of overpass bridges were summarized and analyzed，and it was proven that anti-collision and anti-scratching were two important requirements of pier protection.Then，the new concept of double protection and corresponding technical schemes were put forward.The first protection adopted the way of setting concrete barriers or ship-shaped elevating members on the periphery of the pier to prevent vehicles from impacting the pier，and the second protection used the self-wrapped steel plate or aluminum foam plate to prevent vehicles from scratching the pier.The safety of the pier protection structure schemes was verified by computer simulation and unit test，and …

Research On Yolov 5‑Ganomaly Joint Algorithm For High‑Strength Bolt Detection, Xie Haibo, Zhu Weijun, Zhang Bi2, Zhang Dahai

Journal of China & Foreign Highway

High-strength bolt loosening detection of bridges faces problems such as heavy workload，small targets，many anomalies，and difficult collection.Therefore，this paper proposed a semi-supervised deep learning model，which could obtain the bolt loosening detection model even with a small number of negative samples and solve the problem of unbalanced model training samples.The accuracy of the YOLOv 5-CT model for bolt target detection reached 98.33%.By preprocessing bolt data，the reconstruction ability of bolt images by the Ganomaly model was improved.When the hidden space vector value was 100，the model had the highest SAUC and the best discriminant performance.In the model test stage，the threshold of abnormal fraction was set …

Experimental Study On Effect Of Temperature On Bound Water Adsorption And Deformation Of High Liquid Limit Soil, Zi Yinhui, Shen Xuning, Zhang Hao, Zhang Rui, Li Lu

Journal of China & Foreign Highway

In order to study the effect of temperature change on the bound water content adsorbed by high liquid limit clay and the deformation law of high liquid limit clay embankment，the high liquid limit clay in Hainan Province was selected as the primary research object and compared with the low liquid limit sand in Hunan Province.The effect of temperature on the bound water content adsorbed by high liquid limit clay was explored through a nuclear magnetic resonance test.In addition，the effect of temperature on the deformation of high liquid limit clay embankments was analyzed through the consolidation test with a temperature-controlled consolidometer.The …

Temperature And Strain Development Characteristics Of Tunnel Concrete Based On Double Grating Sensors, Fang Jianping, Zhang Mengxi, Yao Xiaonan

Journal of China & Foreign Highway

In order to better prevent tunnel concrete from cracking，the development law of concrete temperature and strain was studied.Based on the connection project of Sanjiang Middle Road in the Smart New City of Quzhou，a data acquisition system was established to monitor concrete temperature and strain on site.The defects of the traditional method that the temperature and strain monitoring are insensitive，and the monitoring data is discontinuous were overcome.In addition，the high-performance double grating temperature-strain sensor was used to simultaneously monitor the temperature and strain at the same position，and the temperature compensation method was used to overcome the influence of the ambient temperature on …

Properties And Mechanism Of Reclaimed Asphalt Based On Sbs Structure Repair, Feng Xinjun, Yang Hongyang, Xiao Honghai, Zhu Ziqiang

Journal of China & Foreign Highway

At present，the common asphalt regenerant is used for treating the aged styrene-butadiene-styrene （SBS） modified asphalt in China，which fails to repair the SBS cross-networking structure，resulting in the poor regeneration effect of the aged SBS modified asphalt.In this study，a new reactive regenerator containing a structural repair agent，extractive oil，plasticizer，solubilizer，and a small amount of SBS was used to regenerate the aged SBS modified asphalt.The conventional properties and rheological properties of reclaimed SBS modified asphalt were studied by three index tests，Brookfield viscosity test，dynamic shear rheological test，and low temperature bending rheological test.Then，a fluorescence microscope and infrared spectrometer were used to study the regeneration mechanism of the …