Open Access. Powered by Scholars. Published by Universities.®

Civil and Environmental Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 13171 - 13200 of 39816

Full-Text Articles in Civil and Environmental Engineering

Modeling And Simulation Of Damage In The Brazilian Indirect Tension Test Using The Finite-Discrete Element Method, Jeremiah C. Leyba Aug 2018

Modeling And Simulation Of Damage In The Brazilian Indirect Tension Test Using The Finite-Discrete Element Method, Jeremiah C. Leyba

Civil Engineering ETDs

The Brazilian indirect tension test is used to investigate possible correlations between progressive damage and associated permeability changes. The test offers ease of replicability with a damage behavior known to lead to fracture openings as a tool for interpreting the indirect tensile strength of concrete and rocks. This behavior can lend insight into the nature of tensile damage and fracture progression in association with changes in permeability. The nature of these brittle materials is known to exhibit rapid failures in the Brazilian indirect tension test and require a method to retard the progression of damage for the possibility of acquiring …


Safety Ramifications Of A Change In Pedestrian Crosswalk Law: A Case Study Of Oregon, Usa, Yue Ke, Konstantina Gkritza Aug 2018

Safety Ramifications Of A Change In Pedestrian Crosswalk Law: A Case Study Of Oregon, Usa, Yue Ke, Konstantina Gkritza

Lyles School of Civil Engineering Faculty Publications

Pedestrians are some of the most vulnerable road users as they are not protected by safety devices, and must also share the road with vehicles traveling at dangerous speeds, particularly during road crossings. In 2011, the state of Oregon changed their traffic laws to be more accommodating to pedestrians by giving right of way to pedestrians using a crosswalk, regardless if whether the crosswalk is marked or unmarked. This paper estimates a panel logit model to evaluate the efficacy of the law in preventing pedestrian fatalities. Pedestrian fatalities are shown to decrease over time, with smaller likelihood of a fatality …


Analysis And Research Of Cruise Ship Safety At Wusongkou International Cruise Ship Terminal, Zhanglong Wang Aug 2018

Analysis And Research Of Cruise Ship Safety At Wusongkou International Cruise Ship Terminal, Zhanglong Wang

Maritime Safety & Environment Management Dissertations (Dalian)

No abstract provided.


Horizontal Integration In The Port Industry In China Challenges And Outlook, Jiren Chen Aug 2018

Horizontal Integration In The Port Industry In China Challenges And Outlook, Jiren Chen

World Maritime University Dissertations

No abstract provided.


A Study Of Bus High-Resolution Gps Speed Data Accuracy, Miguel Figliozzi, Nicholas B. Stoll Aug 2018

A Study Of Bus High-Resolution Gps Speed Data Accuracy, Miguel Figliozzi, Nicholas B. Stoll

Civil and Environmental Engineering Faculty Publications and Presentations

The recent availability of high-frequency transit (HFT) GPS data for buses has allowed the estimation of detailed bus-travel speed profiles between bus stops. HFT data are defined as data comprising GPS vehicle trajectory recorded at or less than 5 s intervals. With HFT data it is now possible to measure changes in bus speed at specific locations of interest, such as intersections, ramps, crosswalks, and so on. Previous research efforts have not compared GPS-based bus speeds with general traffic speeds at specific locations between stops. This research fills this knowledge gap, utilizing accurate stationary radar speed data as a baseline …


Characterization Of Grain-Size Distribution, Thermal Conductivity, And Gas Diffusivity In Variably Saturated Binary Sand Mixtures, T.K.K. Chamindu Deepagoda, Kathleen Smits, J.R.R.N. Jayarathne, Benjamin M. Wallen, Timothy J. Clough Aug 2018

Characterization Of Grain-Size Distribution, Thermal Conductivity, And Gas Diffusivity In Variably Saturated Binary Sand Mixtures, T.K.K. Chamindu Deepagoda, Kathleen Smits, J.R.R.N. Jayarathne, Benjamin M. Wallen, Timothy J. Clough

Civil Engineering Faculty Publications - Archive

Characterization of differently textured porous materials, as well as different volumetric porous media mixtures, in relation to mass and heat transport is vital for many engineering and research applications. Functional relations describing physical (e.g., grain-size distribution, total porosity), thermal, and gas diffusion properties of porous media and mixtures are necessary to optimize the design of porous systems that involve heat and gas transport processes. However, only a limited number of studies provide characterization of soil physical, thermal, and gas diffusion properties and the functional relationships of these properties under varying soil water contents, especially for soil mixtures, complicating optimization efforts. …


Development Of Self-Healing Mechanisms For Asphalt Pavements, Max Abelardo Aguirre Deras Aug 2018

Development Of Self-Healing Mechanisms For Asphalt Pavements, Max Abelardo Aguirre Deras

LSU Doctoral Dissertations

Self-healing mechanisms, such as microcapsules or hollow-fibers, filled with an asphalt rejuvenator present an emerging technology that would enhance an asphalt mixture’s resistance to cracking damage caused by vehicular and environmental loading. The objectives of this study were to: (a) Evaluate the effects of asphalt rejuvenators on hot-mix asphalt mixtures in order to test its effects on the fundamental engineering properties of the mixtures at high and intermediate temperatures; (b) Develop a synthesis procedure for production of microcapsules and hollow-fibers containing an asphalt rejuvenator; (c) Evaluate the self-healing efficiency of double-walled microcapsules and hollow-fibers filled with an asphalt rejuvenator, through …


Evaluation Of Site Variability And Its Application In Design, Abu Hakim Muhammad Hasan Faisal Aug 2018

Evaluation Of Site Variability And Its Application In Design, Abu Hakim Muhammad Hasan Faisal

LSU Master's Theses

Geotechnical characterization has an important role in engineering geology as well as in implementation of any project. There are several variables and uncertainties involved in characterizing a project site. Four different sources of uncertainties represent the characterization of geotechnical variability, which include spatial variability, measurement error, statistical error and model bias. Spatial variability is expressed in terms of the mean, variance, and scale of fluctuation. Several statistical techniques such as the Gauge R & R, which includes X-Bar/R and ANOVA, and the Second Moment can be applied to compute site variability in terms of the coefficient of variations. Measurement error …


Developing Multi-Scale Models For Water Quality Management In Drinking Water Distribution Systems, Ahmed A. Abokifa Aug 2018

Developing Multi-Scale Models For Water Quality Management In Drinking Water Distribution Systems, Ahmed A. Abokifa

McKelvey School of Engineering Graduate Student Theses & Dissertations

Drinking water supply systems belong to the group of critical infrastructure systems that support the socioeconomic development of our modern societies. In addition, drinking water infrastructure plays a key role in the protection of public health by providing a common access to clean and safe water for all our municipal, industrial, and firefighting purposes. Yet, in the United States, much of our national water infrastructure is now approaching the end of its useful life while investments in its replacement and rehabilitation have been consistently inadequate. Furthermore, the aging water infrastructure has often been operated empirically, and the embracement of modern …


Concurrency Platforms For Real-Time And Cyber-Physical Systems, David Ferry Aug 2018

Concurrency Platforms For Real-Time And Cyber-Physical Systems, David Ferry

McKelvey School of Engineering Graduate Student Theses & Dissertations

Parallel processing is an important way to satisfy the increasingly demanding computational needs of modern real-time and cyber-physical systems, but existing parallel computing technologies primarily emphasize high-throughput and average-case performance metrics, which are largely unsuitable for direct application to real-time, safety-critical contexts. This work contrasts two concurrency platforms designed to achieve predictable worst case parallel performance for soft real-time workloads with millisecond periods and higher. One of these is then the basis for the CyberMech platform, which enables parallel real-time computing for a novel yet representative application called Real-Time Hybrid Simulation (RTHS). RTHS combines demanding parallel real-time computation with real-time …


Synthesis Of Crumpled Graphene And Titanium Dioxide Based–Nanomaterials And The Application To Carbon Dioxide Photoreduction, Yao Nie Aug 2018

Synthesis Of Crumpled Graphene And Titanium Dioxide Based–Nanomaterials And The Application To Carbon Dioxide Photoreduction, Yao Nie

McKelvey School of Engineering Graduate Student Theses & Dissertations

With the rapid development of the economy, increasing combustion of fossils fuels has caused an increase in the atmospheric carbon dioxide (CO2) level, and has led to global climate change. As a mitigation approach, CO2 capture and conversion (CCC) can not only capture CO2, but also convert it to useable products, such as hydrocarbon fuels. Photocatalytic reduction is an attractive CCC option that directly harnesses inexpensive and abundant solar energy. Titanium dioxide (TiO2) is a widely used semiconductor for photocatalysis, and graphene nanosheets are a promising material for use in fabricating graphene-TiO2 hybridized photocatalysts. To realize the application of these …


Pedestrian Bridge Test Demonstration, Genda Chen, R. Zoughi Aug 2018

Pedestrian Bridge Test Demonstration, Genda Chen, R. Zoughi

INSPIRE-UTC Annual Meetings

The INSPIRE UTC, with permission and the cooperation of Missouri S&T Facilities Operations, is conducting research testing on the Computer Science Pedestrian Bridge through the end of September 2018. The technologies employed in the Pedestrian Bridge test include: microwave imaging, ground penetrating radar and impact-echo tests, hyperspectral, and thermal imaging.


Developing A Robotic Simulator And Video Games For Professional And Public Training, Sushil Louis Aug 2018

Developing A Robotic Simulator And Video Games For Professional And Public Training, Sushil Louis

INSPIRE-UTC Annual Meetings

Civil engineers are not educated with robotics. They need to be trained on the job with effective tools. The most recent simulation trainer that the PI has built is currently being used by the United States Navy to train surface warfare officers in decision making under stress. In a crowded in-port environment, the crew on a ship’s bridge is trained to probe and identify suspicious boat behavior within the port’s traffic pattern. Officers in charge of the simulation training lesson use software for high-level control of dozens of other ships, boats, and aircrafts that quickly react and adapt to the …


Training Framework Of Robotic Operation And Image Analysis For Decision-Making In Bridge Inspection And Preservation, Ruwen Qin Aug 2018

Training Framework Of Robotic Operation And Image Analysis For Decision-Making In Bridge Inspection And Preservation, Ruwen Qin

INSPIRE-UTC Annual Meetings

Inspection and preservation of existing transportation infrastructure to extend their service life is an effective way of mitigating the pressure of steadily growing transportation demands on the aging infrastructure. Their current practice, though, represents one of the most costly operations in state departments of transportation.

The INSPIRE University Transportation Center will develop a remotely-controlled robotic platform that helps with these labor-intensive tasks and allows engineers to focus on decision-making processes. An important mission of INSPIRE is to leverage users’ capability of implementing, and interacting with, the robotic platform. Therefore, a long-term plan has been made to create a framework of …


Autonomous Wall-Climbing Robots For Inspection And Maintenance Of Concrete Bridges, Jizhong Xiao Aug 2018

Autonomous Wall-Climbing Robots For Inspection And Maintenance Of Concrete Bridges, Jizhong Xiao

INSPIRE-UTC Annual Meetings

Since 2002, the PI’s group has developed four generations of wall-climbing robots for NDE inspection of civil infrastructure. These robots combine the advantages of aerodynamic attraction and suction to achieve a desirable balance of strong adhesion and high mobility. They don’t require perfect sealing and can thus move on smooth and rough surfaces, such as brick, concrete, stucco, wood, glass, and metal. For example, Rise-Rover uses two drive modules to carry their middle compartment with payload up to 450 N. Ground penetrating radar (GPR)-Rover and Mini GPR-Rover are custom designed to carry a GSSI’s GPR antenna for subsurface defect detection …


Climbing Robots With Automated Deployment Of Sensors And Nde Devices For Steel Bridge Inspection, Hung La Aug 2018

Climbing Robots With Automated Deployment Of Sensors And Nde Devices For Steel Bridge Inspection, Hung La

INSPIRE-UTC Annual Meetings

The PI was a research scientist/faculty at Rutgers University who successfully developed in 2014 a Robotic Assisted Bridge Inspection Tool (RABIT) for bridge deck inspections. Other bridge elements, such as girders and columns, or even underside of bridge decks are difficult to access and remain a challenge for efficient inspection. Like visual inspection, current practices for bridge maintenance are equally time consuming and expensive. Automation of simple maintenance actions such as bearing cleaning and concrete sealing with robots will lead to a leap forward to the next-generation strategy of bridge maintenance.

This project aims to develop and prototype automated climbing …


Mobile-Manipulating Uavs For Sensor Installation, Bridge Inspection And Maintenance, Paul Oh Aug 2018

Mobile-Manipulating Uavs For Sensor Installation, Bridge Inspection And Maintenance, Paul Oh

INSPIRE-UTC Annual Meetings

Mobile manipulating UAVs have great potential for bridge inspection and maintenance. Since 2002, the PI has developed UAVs that could fly through in-and-around buildings and tunnels. Collision avoidance in such cluttered near-Earth environments has been a key challenge. The advent of light-weight, computationally powerful cameras led to breakthroughs in SLAM even though SLAM-based autonomous aerial navigation around bridges remains an unsolved problem.

In 2007, the PI integrated a mobile manipulation function into UAVs, greatly extending the capabilities of UAVs from passive survey of environments with cameras to active interaction with environments using limbs. Mobile-manipulating UAVs have since been demonstrated to …


Quantitative Bridge Inspection Ratings Using Autonomous Robotic Systems, Anil Agrawal Aug 2018

Quantitative Bridge Inspection Ratings Using Autonomous Robotic Systems, Anil Agrawal

INSPIRE-UTC Annual Meetings

The 2001 study sponsored by FHWA raised serious concern on the consistency and reliability of visual inspection. Although consistent ratings can be obtained with a good QA/QC program, based on a recent study by the PI, the concern for reliability of defect detection remains. With the adoption of the recent AASHTO Manuel for Bridge Element Inspection, the new inspection approach not only requires rating for bridge elements, but also the location and extent of deterioration. Since autonomous robotic systems generate an enormous amount of inspection data, deducing from the data to a simple rating along with the location and extent …


Hyperspectral Image Analysis For Mechanical And Chemical Properties Of Concrete And Steel Surfaces, Genda Chen Aug 2018

Hyperspectral Image Analysis For Mechanical And Chemical Properties Of Concrete And Steel Surfaces, Genda Chen

INSPIRE-UTC Annual Meetings

A typical human eye will respond to wavelengths from approximately 400 to 700 nm. A hyperspectral camera can extend the wavelength to as high as 2500 nm. This extension will allow engineers to find objects, identify materials, and detect processes on structural surface, which cannot be done with visual inspection.

This project aims to develop an open-source catalogue of concrete and steel surfaces and their spectral/spatial features (discoloration, characteristic wavelength, roughness, texture, shape, etc.), extract spatial/spectral features of hyperspectral images, and develop/train a multi-class classification or regression classifier through machine learnings (supervised and/or semi-supervised), and validate the classifier as a …


3d Microwave Camera For Concrete Delamination And Steel Corrosion Detection, R. Zoughi Aug 2018

3d Microwave Camera For Concrete Delamination And Steel Corrosion Detection, R. Zoughi

INSPIRE-UTC Annual Meetings

Corrosion of embedded steel reinforcement in concrete leads to concrete cracking and delamination, followed by increased salt and moisture permeation and further damage. Invisibility of the embedded rebar in combination with physical inaccessibility in elevated bridges presents a challenge in the assessment of RC bridge elements. Wideband (3D) microwave synthetic aperture radar (SAR) imaging techniques that can be integrated into a UAV offer a practical solution to overcome this challenge.

This project aims to develop and optimize a 3D microwave camera for bridge inspection on a UAV platform, quantify its performance for steel corrosion evaluation and concrete delamination detection in …


Thermally-Stable Passive Antenna Sensor For Strain And Crack Monitoring, Dan Li, Yang Wang Aug 2018

Thermally-Stable Passive Antenna Sensor For Strain And Crack Monitoring, Dan Li, Yang Wang

INSPIRE-UTC Annual Meetings

An RFID patch antenna sensor can be used to wirelessly measure the strain and/or crack on a structural surface through the shift of its electromagnetic resonance frequency. According to electromagnetic theory, the resonance frequency �R of a patch antenna has an approximately linear relationship with strain �: [Formula]

Previous design of antenna sensor with Rogers RT/duroid® 5880 substrate is sensitive to temperature change. A new RFID patch antenna sensor with thermally-stable substrate material Rogers RT/duroid® 6202 is designed and tested through both numerical simulation and laboratory experiments. A new RFID chip with much smaller footprint is adopted in the …


Deep Semantic 3d Visual Metric Reconstruction Using Wall-Climbing Robot, Liang Yang, Bing Li, Yong Chang, Jizhong Xiao Aug 2018

Deep Semantic 3d Visual Metric Reconstruction Using Wall-Climbing Robot, Liang Yang, Bing Li, Yong Chang, Jizhong Xiao

INSPIRE-UTC Annual Meetings

This project introduces an inspection method using a deep neural network to detect the crack and spalling defects on concrete structures performed by a wall-climbing robot. First, we create a pixel-level semantic dataset which includes 820 labeled images. Second, we propose an inspection method to obtain 3D metric measurement by using an RGB-D camera-based visual simultaneous localization and mapping (SLAM), which is able to generate pose coupled key-frames with depth information. Therefore, the semantic inspection results can be registered in the concrete structure 3D model for condition assessment and monitoring. Third, we present our new generation wall-climbing robot to perform …


Modeling Hose Dynamics For Unmanned Aerial Vehicles, Blake Hament, Paul Y. Oh, Autonomous Systems Lab (Dasl) Aug 2018

Modeling Hose Dynamics For Unmanned Aerial Vehicles, Blake Hament, Paul Y. Oh, Autonomous Systems Lab (Dasl)

INSPIRE-UTC Annual Meetings

Bridges and other large pieces of infrastructure accumulate massive amounts of dirt, dust, and other particulates that can obscure the structure when scanning to discern structural integrity. Traditionally, these particulates have been removed by humans operating handheld compressed-air hoses, often while mounting ladders -- a risky and inefficient task. To improve infrastructure scanning, unmanned aerial vehicles (UAV) equipped with hoses could be used to clean the structure in place of the current method.

The challenge in equipping a UAV with a hose is compensating for the reaction forces and torques produced by fluids expelled by the hose. In order to …


Parallel Manipulator-Gripper For Mobile Manipulating Uavs, Dongbin Kim, Paul Y. Oh, Autonomous Systems Lab (Dasl) Aug 2018

Parallel Manipulator-Gripper For Mobile Manipulating Uavs, Dongbin Kim, Paul Y. Oh, Autonomous Systems Lab (Dasl)

INSPIRE-UTC Annual Meetings

Unmanned Aerial Vehicles (UAVs) are originally developed for military, but have been developed over time to time for valuable roles in surveillance, work-assistant, and intelligence for both civilian and military operations.

The ability of UAVs that manipulate or carry objects can expand the type of tasks achieved by unmanned aerial systems. High degree of freedom robots with dexterous arm can lead to various applications. Most of manipulators are serial, each motor on each joint affects on stabilizing UAVs. Our lab , DASL , has presented parallel mechanism manipulator for UAVs. It results in less impact on center of gravity(CoG) of …


Integrated Fiber Optic Sensors For Strain, Temperature And Corrosion-Induced Mass Loss Measurement, Chuanrui Guo, Liang Fan, Genda Chen Aug 2018

Integrated Fiber Optic Sensors For Strain, Temperature And Corrosion-Induced Mass Loss Measurement, Chuanrui Guo, Liang Fan, Genda Chen

INSPIRE-UTC Annual Meetings

In this study, a fiber optic sensing system based on long period fiber gratings (LPFG) in LP06 and LP07 modes is designed, fabricated and tested for simultaneous measurements of strain, temperature and corrosion-induced mass loss. It consists of three steel tubes and several Fe-C coated LPFG sensors for long- and short-term corrosion monitoring, respectively, when deployed in proximity and parallel to a steel member. Graphene/silver nanowire (Gr/AgNW) composite was coated on the LPFG surface for efficient Fe-C electroplating due to its high optical transparency and conductivity. The sensor was subjected to both tensile strain and temperature, and submerged in 3.5 …


Bridge Resilience Assessment With Inspire Data, Yijian Albert Zhang, Reginald Desroches, Iris Tien Aug 2018

Bridge Resilience Assessment With Inspire Data, Yijian Albert Zhang, Reginald Desroches, Iris Tien

INSPIRE-UTC Annual Meetings

In this research, we proposed analytical models validated with numerical results to assess how inspection-collected data on corrosion can be used to update bridge models and predict performance under future events. A detailed investigation of the vulnerability of bridges due to corrosion at both component and global levels. The results show the impact of corrosion-induced degradation on the seismic fragility of reinforced concrete columns under various failure modes, e.g., flexural, shear, and lap-spliced failures. As increasing amounts of data are collected on the states of bridges, the results show how these data can be used to update bridge assessments and …


Microwave Imaging For Corroded Rebars And Delamination In Concrete Structures, Matthew Dvorsky, Stephon Barker, Mohammad Tayeb Ahmad Ghasr, R. Zoughi Aug 2018

Microwave Imaging For Corroded Rebars And Delamination In Concrete Structures, Matthew Dvorsky, Stephon Barker, Mohammad Tayeb Ahmad Ghasr, R. Zoughi

INSPIRE-UTC Annual Meetings

Corrosion of embedded steel reinforcement bars (rebars) in concrete leads to concrete cracking and delamination, which in turn leads to increased salt and moisture permeation and further damage. This study aims to evaluate the effectiveness of microwave imaging for the characterization of this corrosionand delaminationof steel rebar embedded in concrete.


Hyperspectral Image Analysis For Mechanical And Chemical Properties Of Concrete And Steel Surfaces, Liang Fan, Paul Manley, Huaishuai Shang, Abdullah Alhaj, Hongyan Ma, Genda Chen Aug 2018

Hyperspectral Image Analysis For Mechanical And Chemical Properties Of Concrete And Steel Surfaces, Liang Fan, Paul Manley, Huaishuai Shang, Abdullah Alhaj, Hongyan Ma, Genda Chen

INSPIRE-UTC Annual Meetings

According to the 2017 ASCE Report Card, 39% and 15% of 614,387 bridges in the U.S. are more than 50 years and 40 to 49 years, respectively. The number of deficient bridges is increasing. One of the most common causes of reinforced concrete deterioration is corrosion of steel reinforcing bars. Currently, most bridges are visually inspected every two years using boom/snooper trucks to get access to various areas to be inspected. The subjective visual inspection often leads to inconsistent results that are less useful in bridge management. Hyperspectral camera, installed on an unmanned aerial vehicle, can potentially supplement visual inspection …


Uav-Enabled Measurement On Magnetic Field Of Smart Rocks For Bridge Scour Monitoring, Haibin Zhang, Zhaochao Li, Genda Chen Aug 2018

Uav-Enabled Measurement On Magnetic Field Of Smart Rocks For Bridge Scour Monitoring, Haibin Zhang, Zhaochao Li, Genda Chen

INSPIRE-UTC Annual Meetings

Scour and other hydraulic induced failures accounted for 58% of over 1,500 bridge collapses in the U.S. Bridge scour is the engineering term for the erosion of soil surrounding a bridge foundation as a result of water current. Monitoring with fixed and/or portable instrumentations is one of the most effective measures in mitigating scour hazards. However, fixed instrumentation with sensors installed prior to flood events cannot detect scour other than the area instrumented. It is susceptible to the harsh environment during a flood event. Portable instrumentation is difficult to deploy during a severe flood event due to safety consideration and/or …


Battery-Free Antenna Sensors For Strain And Crack Monitoring Of Bridge Structures, Yang Wang Aug 2018

Battery-Free Antenna Sensors For Strain And Crack Monitoring Of Bridge Structures, Yang Wang

INSPIRE-UTC Annual Meetings

Fatigue cracks need to be monitored in fatigue critical elements. Previous research by the PI produced a radiofrequency identification (RFID) sensor prototype that can accurately measure tens of micro-strains in laboratory. The antenna sensor was made on a glass microfiber-reinforced polymer substrate. Although accurate for strain measurement and detection of fatigue cracks, the sensor performs less satisfactorily in field conditions since the substrate material (RT/duroid® 5880) is susceptible to thermal effect. In addition, a wireless interrogation distance by a general-purpose commercial RFID reader is limited to the order of meter, which is not desirable with the operation of a UAV. …