Engineering Commons^™

Detection Method Of Rural Road Pavement Damage Based On Smart Phone, Zhang Yang, He Li, Tang Qingzhou, Zhang Dejin

Journal of China & Foreign Highway

Automatic detection of rural road pavement damage is a critical prerequisite for scientific maintenance. To address issues such as high false detection rates, missed detection, and the inability to quantify damage when using smartphones for pavement damage detection, this paper proposes a novel detection method. The proposed method involves using a smartphone to capture pavement images. A region of interest is first selected in the image, followed by weighted least-squares filtering, Canny edge detection, and Hough transform line detection to identify the pavement, minimizing environmental interference and reducing false detection rates. Perspective transformation is then applied to the pavement region …

Analysis Of Socket Depth Between Bridge Pier And Cap With Improved Socket Connection, Ge Jiping, Lai Luqi, Wang Zhigang

Journal of China & Foreign Highway

Traditional prefabricated socket-type bridge piers are limited in engineering applications due to the requirement for deep socket connections. This paper proposes an improved socket connection design incorporating measures such as side shear keys, U-shaped anti-punching reinforcement at the pier base, high-strength non-shrink grouting materials, and large-diameter corrugated metal pipe constraints. The current formulas for calculating socket depth in socket-type connections are reviewed, and a modified calculation formula for improved socket-type piers is presented. The influence of factors such as axial compression ratio and concrete strength on socket depth is discussed. The analysis shows that the improved socket connection reduces socket …

Finite Element Model Updating Of Long Span Suspension Bridge Based On Optimized Radial Basis Function Neural Network, Yang Wenfu, Chen Xin

Journal of China & Foreign Highway

To achieve accurate prediction and analysis of the structural behavior of long-span suspension bridges, a finite element model updating method is proposed. An optimized radial basis function neural network (RBFNN) is constructed using a genetic algorithm to map the relationship between structural responses and parameters. Using structural dynamic responses as inputs, the model updating was performed on a long-span suspension bridge using both numerical simulation data and actual data from a health monitoring system. The results show that the optimized RBFNN effectively represents the functional relationship between structural responses and parameters to be updated. Model updating via the optimized RBFNN …

Key Technology For Design Of Composition Section Of Hybrid Girder Cable‐Stayed Bridge, Tian Bo, Song Lubing

Journal of China & Foreign Highway

The main bridge of the Yibin Nanxi (Xianyuan) Yangtze River Bridge adopts an asymmetric hybrid girder cable-stayed design with a 572 m main span. The main span and the north-side span utilize hybrid girders, while the south-side span uses a concrete girder. A steel-concrete composite section is introduced between the south-side span and the main span. This paper explores multiple schemes for the location and key structural design of the steel-concrete composite section, prioritizing a full-section rib connection with a pressure-bearing shear transfer transition structure. The structural rationality and construction feasibility were verified through on-site static model tests, failure model …

Analysis And Reinforcement Measures For Unconventional Cracks In Gravity U‐Type Abutment, Cheng Kun, Du Yinguang, Liu Zhang

Journal of China & Foreign Highway

Horizontal cracking at the foundation level is uncommon in gravity U-type abutments. This paper investigates the causes and reinforcement measures for unconventional horizontal cracks in the foundation and vertical cracks in the abutment wall of a gravity U-type abutment on a highway bridge. Survey and analysis results show that the vertical cracks in the abutment wall are structural cracks caused by excessive reaction forces from permanent loads combined with the impact loads from vehicles at expansion joints. The horizontal foundation cracks result from the presence of filler interlayers at the foundation, which softened over time due to water exposure, leading …

Analysis On Vehicle‐Bridge Interaction Of High‐Pier Continuous Rigid Frame Bridge, Liu Huaquan, Yang Dehai, Cai Chengqi, Huang Zhenming, Chen Zhouqi

Journal of China & Foreign Highway

To study the dynamic response characteristics of the vehicle-bridge system under moving vehicle loads, a three-span high-pier continuous rigid frame bridge was selected as the research object. A 2-axle, 7-degree-of-freedom vehicle model was applied to explore the effects of vehicle speed, number of vehicles, and vehicle load on the dynamic response of the vehicle-bridge system. The results show that vehicle speed has minimal impact on the peak displacement response of the bridge. However, when vehicles travel at the same speed, the peak displacement response differs across bridge spans, with resonance occurring at a vehicle speed of 40 km/h. As the …

Research On Application Of Equivalent Stiffened Plate Elements In Local Stability Calculation Of U‐Shaped Stiffened Plates, Chen Xiangjun

Journal of China & Foreign Highway

To address the issue of excessively large computational models in the numerical simulation of U-shaped stiffened plates in large-span flat steel box girder main girders, this paper proposes a finite element calculation theory using equivalent stiffened plate elements and a simplified method for U-shaped stiffened plates. By simplifying the U-shaped small box ribs in U-shaped stiffened plates into equivalent stiffening strips, the transverse stiffness of the cover plate is redistributed, and the effect of equivalent stiffeners on the stress of the plates is calculated. Stability analysis was conducted using Fortran language developed on the Ansys platform, and the results were …

Optimization Research Of Laying Method And Material Type Selection Of Thermal Insulation Layer For Tunnels In Cold Region, Wu Tao, Liu Zhichun, Liu Xuejiao, Zhang Hongfei

Journal of China & Foreign Highway

To address the issue of frost damage in tunnels in cold regions, research on thermal insulation and frost prevention is crucial. This paper utilizes an improved analytic hierarchy process combined with grey relational analysis to identify optimal insulation materials suitable for different laying methods that provide effective insulation. Numerical simulation methods were then used to calculate and analyze the tunnel temperature field under various combinations of insulation materials and laying methods. Based on the “composite temperature field” comparison results, the optimal insulation scheme was determined. The results show that the “off-wall laying + Furritek insulation board” combination is the optimal …

Experimental Study On Influence Of Phosphorus Slag Powder On Pervious Concrete, Lou Jianxin, Yang Jianyong, Zhang Yuxian, Li Jun, Wang Jie, Liu Jian

Journal of China & Foreign Highway

This paper investigates the effects of replacing cement with phosphorus slag powder on the mechanical properties, permeability, and pavement performance of pervious concrete. The results show that incorporating a certain amount of phosphorus slag powder as a partial replacement for cement in pervious concrete is feasible. When the replacement ratio of phosphorus slag powder is within 10%, it enhances the strength of pervious concrete. The optimal replacement ratio of phosphorus slag powder is 8%, achieving a compressive strength of 24.18 MPa, a void ratio of 15.37%, and a permeability coefficient of 2.45 mm/s, which meet the requirements for fully permeable …

Dynamic Load Response Analysis Of Rubber Powder Modified Asphalt Mixture, Yang Sanqiang, Sun Shuang, Li Qian, Liu Xinlei, Qin Lusheng

Journal of China & Foreign Highway

To investigate the mechanical response of rubber powder modified asphalt pavement under dynamic loads, this paper, based on the “Full-Scale Accelerated Pavement Loading Testing” project, designed experimental schemes for asphalt mixtures with varying rubber powder contents. The paper employed accelerated loading test equipment to evaluate the stress and deformation of pavement structures, obtaining dynamic strain response data to analyze the strain response patterns of various structural layers. Combining finite element numerical simulations and a custom loading program, the paper examined the dynamic responses of rubber powder modified asphalt pavements under variable temperature conditions. The results show that through microscopic testing, …

Aging Asphalt Concrete Cracking Performance Under Different Cyclic Loading Frequencies, Yan Jingchen, Ma Yanpei, Yan Junjie

Journal of China & Foreign Highway

Using digital speckle technology, this paper examines the crack propagation behavior of asphalt concrete under repeated loading, analyzing the crack propagation mechanism from macro- and micro-perspectives under different aging conditions and loading frequencies for four types of asphalt concrete. The results show that the basalt fiber-reinforced asphalt concrete beam specimens delay the onset of the unstable crack propagation phase, thus extending the service life of the asphalt concrete. Aging accelerates the progression of asphalt concrete to the unstable crack propagation point, advancing this stage by 4%-5%. Under repeated loading frequencies of 5 Hz, 10 Hz, and 15 Hz, the damage …

Design And Development Of Two And Three Dimensional Integration System For Highway Based On Webgis, Che Defu, Zhou Huajun

Journal of China & Foreign Highway

To address the inefficiencies, lengthy cycles, and high resource demands in the process of determining the annual project database for highway maintenance quotas in Liaoning Province, a 2D and 3D integration system for highways based on WebGIS was designed and developed. This system not only provides a macroscopic view of the geographic distribution and overall characteristics of highways but also offers a detailed and intuitive representation of the spatial relationships and conditions of roadbeds and pavement damage. The system meets the needs of modern highway management and can serve as a reference for other highway maintenance quota tasks.

Study On Relationship Of Solar Radiation Temperature And Pier‐Top Displacement Of Ultra‐High Thin‐Walled Hollow Pier, Liu Zhishen, Zhang Yifei, Song Fei, Su Jufeng, Ren Xiang

Journal of China & Foreign Highway

Thin-walled hollow piers are widely used in high-pier and long-span continuous rigid-frame bridges. Solar radiation-induced displacements at the tops of ultra-high thin-walled hollow piers can negatively affect the structural alignment and stress during construction and post-construction phases. Based on a 180 m high thin-walled hollow pier of a large bridge in Shaanxi Province, this paper analyzes the temperature field and pier-top displacement using data collected during two 24-hour periods: August 28-29 and October 11-12. The temperature field and pier-top displacement patterns over time were studied using finite element analysis. The results show that the temperature difference between the north and …

Model Test Study On Mechanical Characteristics Of Spherical Joints In Multi‐Point Support Swivel System, Zeng Lifei

Journal of China & Foreign Highway

As a critical load-bearing component in bridge swivel systems, the mechanical behavior of spherical joints is essential for the safety of bridge swiveling operations. This study focuses on the spherical joints of a multi-point support swivel system for the bridge over the Xiangyang North Marshalling Yard. Model tests were conducted to analyze the effects of the number of supporting legs, swivel speed, track smoothness, and wind load on the stress of spherical joints. The stress variation patterns of spherical joints under different working conditions were investigated. The results show that increasing the number of supporting legs improves the uniformity of …

Selection Of Phase Change Materials For Asphalt Pavement Based On Molecular Dynamics Simulation, Liu Fujun, Tian Xin, Liang Meichen, Guo Meng

Journal of China & Foreign Highway

Phase change materials (PCMs) have significant application potential in temperature regulation for asphalt pavements. To select suitable PCMs for road applications, this paper utilizes molecular dynamics simulation to analyze the molecular behaviors of lauric acid and polyethylene glycol (PEG). Experimental studies were conducted to validate the simulation results. The results show that molecular dynamics simulation provides an efficient and convenient method for comparing the performance of PCMs. PEG outperforms lauric acid in terms of molecular density, cohesive energy density, solubility parameters, and thermal conductivity, making it more suitable as a phase change material for asphalt pavements.

Study On Alkali Excitation Mechanism Of Large Dosage Slag Fine Powder, Mei Yang

Journal of China & Foreign Highway

To reveal the alkali excitation mechanism of high-dosage slag, this paper combines a three-factor, three-level orthogonal design with macro- and micro-performance tests and microstructure analysis. The effects of different activators, including Ca(OH)2, Na2SiO3, Na2SO4, and CaSO4, in single and dual combinations on the initial and final setting times, pore solution pH, and strength of concrete were explored. The results show that the impact on the strength of hardened paste of composite cementitious materials is ranked as: activator type > dosage > dual-mix ratio. The optimal dual-mix dosage is 4%, with the best combination being Ca(OH)2 and Na2SiO3 at a ratio of 5:1. …

Study On Microstructure Of Asphalt Modified By Oil‐Coal Blend, Guo Pengfei, Zhou Xinfeng

Journal of China & Foreign Highway

To investigate the microstructure and modification mechanism of asphalt modified with oil-coal blend, SK-90# asphalt was mixed with 5%, 10%, 15%, 20%, and 25% (external blending method) oil-coal blend to produce modified asphalt. The performance and microstructural changes of the modified asphalt were analyzed using contact angle testing, infrared spectroscopy, cross-sectional SEM, and X-ray photoelectron spectroscopy. The results show that the oil-coal blend exhibits good compatibility with asphalt. During the modification process, esterification reactions occurred, resulting in a decrease in hydroxyl-containing aromatic compounds and an increase in carbonyl-containing aromatic compounds. Macroscopically, the oil-coal blend-modified asphalt demonstrated excellent high-temperature performance.

Analysis Of Expressway Routine Maintenance Performance Management Based On Dea, Li Yuhuan, Shi Xiaoli, Gao Nan

Journal of China & Foreign Highway

To allocate maintenance resources efficiently and improve management levels, this paper examines the maintenance performance and improvement strategies of routine maintenance projects for 23 expressways in Shaanxi Province using 2018 operational maintenance data and data envelopment analysis. The results show that for some inefficient subsidiaries, traditional radial- and slack-based performance improvement methods are challenging and impractical in the short term. Therefore, a scenario-dependent model-based long-term incremental improvement strategy is proposed. By leveraging relative improvement values, this strategy enables phased improvements for inefficient subsidiaries. It provides a feasible approach for subsidiaries to set lower short-term performance improvement targets while achieving gradual …

The Future Of Mobility-As-A-Service: Trust Transfer Across Automated Mobilities, From Road To Sidewalk, Jacob G. Hunter, Elise Ulwelling, Matthew Konishi, Noah Michelini, Akhil Modali, Anne Mendoza, Jessie Snyder, Shashank Mehrotra, Zhaobo Zheng, Anil R. Kumar, Kumar Akash, Teruhisa Misu, Neera Jain, Tahira Reid

School of Mechanical Engineering Faculty Publications

While trust in different types of automated vehicles has been a major focus for researchers and vehicle manufacturers, few studies have explored how people trust automated vehicles that are not cars, nor how their trust may transfer across different mobilities enabled with automation. To address this objective, a dual mobility study was designed to measure how trust in an automated vehicle with a familiar form factor—a car—compares to, and influences, trust in a novel automated vehicle—termed sidewalk mobility. A mixed-method approach involving both surveys and a semi-structured interview was used to characterize trust in these automated mobilities. Results found that …

Monitoring Pm2.5 Pollution In The North End Of Hartford, Ct, Jocelyn Phung, Kristina Wagstrom

Honors Scholar Theses

Particulate matter (PM) or particle pollution is one of the six criteria air pollutants that can cause harm to human health and the environment; yet, there is a lack of data in many areas of the United States. Particulate matter is a mixture of solid particles and liquid droplets suspended in the air (EPA). Exposure to PM2.5 has been linked to respiratory and cardiovascular conditions. People who live in urban areas are more likely to be exposed to particulate matter as many urban areas are known to have poor air quality. Our goal is to determine how particulate matter levels …

Enabling Security Analysis And Education Of The Ethereum Platform: A Network Traffic Dissection Tool, Joshua Mason Kemp

Masters Theses, 2020-current

Ethereum, the decentralized global software platform powered by blockchain technology known for its native cryptocurrency, Ether (ETH), provides a technology stack for building apps, holding assets, transacting, and communicating without control by a central authority. At the core of Ethereum’s network is a suite of purpose-built protocols known as DEVP2P, which provides the underlying nodes in an Ethereum network the ability to discover, authenticate and communicate confidentiality. This document discusses the creation of a new Wireshark dissector for DEVP2P’s discovery protocols, DiscoveryV4 and DiscoveryV5, and a dissector for RLPx, an extensible TCP transport protocol for a range of Ethereum node …

Du Undergraduate Showcase: Research, Scholarship, And Creative Works, Caitlyn Aldersea, Justin Bravo, Sam Allen, Anna Block, Connor Block, Emma Buechler, Maria De Los Angeles Bustillos, Arianna Carlson, William Christensen, Olivia Kachulis, Noah Craver, Kate Dillon, Muskan Fatima, Angel Fernandes, Emma Finch, Colleen Cassidy, Amy Fishman, Andrea Francis, Stacia Fritz, Simran Gill, Emma Gries, Rylie Hansen, Shannon Powers, Jacqueline Martinez, Zachary Harker, Ashley Hasty, Mykaela Tanino-Springsteen, Kathleen Hopps, Adelaide Kerenick, Colin Kleckner, Ci Koehring, Elijah Kruger, Braden Krumholz, Maddie Leake, Lyneé Alves, Seraphina Loukas, Yatzari Lozano Vazquez, Haley Maki, Emily Martinez, Sierra Mckinney, Audrey Mitchell, Kipling Newman, Audrey Ng, Megan Lucyshyn, Andrew Nguyen, Stevie Ostman, Casandra Pearson, Alexandra Penney, Julia Gielczynski, Tyler Ball, Anna Rini, Christina Rorres, Simon Ruland, Helayna Schafer, Emma Sellers, Sarah Schuller, Claire Shaver, Kevin Summers, Isabella Shaw, Madison Sinar, Claudia Pena, Apshara Siwakoti, Carter Sorensen, Madi Sousa, Anna Sparling, Alexandra Revier, Brandon Thierry, Dylan Tyree, Maggie Williams, Lauren Wols

DU Undergraduate Research Journal Archive

DU Undergraduate Showcase: Research, Scholarship, and Creative Works

Computational Analysis Of Steady Hypersonic Flow Fields Of Nasa Benchmark Geometries Utilizing Ansys Fluent, Aidan Murphy

McKelvey School of Engineering Graduate Student Theses & Dissertations

The Hypersonic International Flight Research Experimentation (HIFiRE) program explores and advances hypersonic aerospace systems by developing a multitude of test flight geometries and conducting experimental test flights to obtain data for use in validation of computational models and results. This study focuses on computational validation of heat flux, and calculation of static pressure profiles, skin friction coefficient profiles, and flow contours. The flow fields studied are for Mach number 7.18 and angles of attack (α) of 0° & 2°. These flow fields include many compressible flow features such as an expansion wave at the intersection of the cone and flat …

When Ai Moves Downstream, Frances S. Grodzinsky, Keith W. Miller, Marty J. Wolf

School of Computer Science & Engineering Faculty Publications

After computing professionals design, develop, and deploy software, what is their responsibility for subsequent uses of that software “downstream” by others? Furthermore, does it matter ethically if the software in question is considered to be artificial intelligent (AI)? The authors have previously developed a model to explore downstream accountability, called the Software Responsibility Attribution System (SRAS). In this paper, we explore three recent publications relevant to downstream accountability, and focus particularly on examples of AI software. Based on our understanding of the three papers, we suggest refinements of SRAS.

The Engineering Challenges Of Designing And Manufacturing A Tensegrity Cup Stand, Yaniv Goulet, Daniel Ferro

Honors Theses

Progressing from a simple idea into a fully developed product is one of the main goals of any engineer. Through Haley Barbour Center for Manufacturing Excellence’s capstone program, the team was tasked with realizing a tensegrity cup stand. The tensegrity structure consists of a top and a bottom of some form only supporting itself by tension. The team had to research the concept, create an initial design, create a prototype of the product, improve the design after the prototype’s mistakes, apply lean principles to improve the manufacturing efficiency, and analyze all the economic impacts of the engineering decisions. In the …

The Design Estimate Of A Warehouse Refrigeration System, Jackson Dear

Honors Theses

The intention of this project was to provide a design and cost estimate for the refrigeration systems within an industrial cold storage distribution center for Magnolia Country Frozen Foods, Inc. in East Rutherford, NJ. The facility includes eighteen 300,000 ft3 units (200 ft x 100 ft x 15 ft). These units require 200 tons of refrigeration at a maintained temperature of 0oF. This project's scope included choosing an optimal refrigeration system, selecting a refrigerant for use within the system, and providing a cost estimate for the purchase of the refrigeration system equipment and for the yearly cost associated with running …

Detection Of Crypto-Ransomware Attack Using Deep Learning, Muna Jemal

Master of Science in Computer Science Theses

The number one threat to the digital world is the exponential increase in ransomware attacks. Ransomware is malware that prevents victims from accessing their resources by locking or encrypting the data until a ransom is paid. With individuals and businesses growing dependencies on technology and the Internet, researchers in the cyber security field are looking for different measures to prevent malicious attackers from having a successful campaign. A new ransomware variant is being introduced daily, thus behavior-based analysis of detecting ransomware attacks is more effective than the traditional static analysis. This paper proposes a multi-variant classification to detect ransomware I/O …

Efficient Approaches For Qubit Mapping On Nisq Computers, Sri Sesha Sailaja Lakshmi Tulasi Khandavilli

Master of Science in Computer Science Theses

—Quantum computing is gaining momentum in revolutionizing the way we approach complex problem-solving. However, the practical implementation of quantum algorithms remains a significant challenge due to the error-prone and hardware limits of near-term quantum devices. For instance, physical qubit connections are limited, which necessitates the use of quantum SWAP gates to dynamically transform the logical topology during execution. In addition, to optimize fidelity, it is essential to ensure that 1) the allocated hardware has a low error rate and 2) the number of SWAP gates injected into the circuit is minimized. To address these challenges, we propose a suite of …

Investigation Of Magnetic Bistability For A Wider Bandwidth In Vibro-Impact Triboelectric Energy Harvesters, Qais Qaseem

Mechanical Engineering Theses

Mechanical energy from vibrations is widespread in the ambient environment. It may be harvested efficiently using triboelectric generators. Nevertheless, the harvesters' effectiveness is restricted because of the limited bandwidth. This thesis proposed a comprehensive theoretical and experimental investigation of a variable frequency energy harvester, which integrates a Vibro-impact triboelectric-based harvester and magnetic nonlinearity to increase the operation bandwidth and improve the efficiency of conventional triboelectric harvesters. A cantilever beam with a tip magnet is aligned with another fixed magnet at the same polarity to induce a nonlinear magnetic repulsive force. A triboelectric harvester is integrated into the system by utilizing …

Sensitive And Makeable Computational Materials For The Creation Of Smart Everyday Objects, Te-Yen Wu Mr

Dartmouth College Ph.D Dissertations

The vision of computational materials is to create smart everyday objects using the materi- als that have sensing and computational capabilities embedded into them. However, today’s development of computational materials is limited because its interfaces (i.e. sensors) are unable to support wide ranges of human interactions , and withstand the fabrication meth- ods of everyday objects (e.g. cutting and assembling). These barriers hinder citizens from creating smart every day objects using computational materials on a large scale.

To overcome the barriers, this dissertation presents the approaches to develop compu- tational materials to be 1) sensitive to a wide variety of …