Thin-Film Sensor For Fatigue Crack Sensing And Monitoring In Steel Bridges Under Varying Crack Propagation Rates And Random Traffic Loads, Xiangxiong Kong, Jian Li, Caroline Bennett, William Collins, Simon Laflamme, Hongki Jo
Civil, Construction and Environmental Engineering Publications
Fatigue cracks are critical structural concerns for steel highway bridges, and fatigue initiation and propagation activity continues undetected between physical bridge inspections. Monitoring fatigue crack activity between physical inspections can provide far greater reliability in structural performance and can be used to prevent excessive damage and repair costs. In this paper, a thin-film strain sensor, called a soft elastomeric capacitor (SEC) sensor, is evaluated for sensing and monitoring fatigue cracks in steel bridges. The SEC is a flexible and mechanically robust strain sensor, capable of monitoring strain over large structural surfaces. By deploying multiple SECs in the form of dense ...
Cementitious Sensors Exhibiting Stopbands In Acoustic Transmission Spectra, 2018 University of New Mexico, Albuquerque
Cementitious Sensors Exhibiting Stopbands In Acoustic Transmission Spectra, Shreya Vemuganti
Shared Knowledge Conference
Ultrasonic monitoring in cementitious materials is challenging due to the high degree of attenuation. In wellbore environments, monitoring becomes more challenging due to inaccessibility. Meta materials, also known as acoustic bandgap materials, exhibit an interesting feature of forbidding the propagation of elastic/sound waves and isolate vibration in a certain frequency band. Traditionally, acoustic bandgap materials are developed with inclusions such as tin, aluminum, gold, steel in a polymer matrix. In this study, we present the development of three-dimensional cementitious sensors capable of exhibiting stopbands in the acoustic transmission spectra using carbon nanotubes. Relatively wide stopbands were engineered using Floquet-Bloch ...
Survival Analysis Of Bridge Superstructures In Wisconsin, 2018 University of Wisconsin-Milwaukee
Survival Analysis Of Bridge Superstructures In Wisconsin, Azam Nabizadeh, Habib Tabatabai, Mohammad A. Tabatabai
Civil and Environmental Engineering Faculty Articles
Although survival analyses have long been used in biomedical research, their application to engineering in general, and bridge engineering in particular, is a more recent phenomenon. In this research, survival (reliability) of bridge superstructures in Wisconsin was investigated using the Hypertabastic accelerated failure time model. The 2012 National Bridge Inventory (NBI) data for the State ofWisconsin were used for the analyses. A recorded NBI superstructure condition rating of 5 was chosen as the end of service life. The type of bridge superstructure, bridge age, maximum span length (MSL) and average daily traffic (ADT) were considered as possible risk factors in ...
Corrosion Resistance Of Pipeline Steel With Damaged Enamel Coating And Cathodic Protection, 2018 Missouri University of Science and Technology
Corrosion Resistance Of Pipeline Steel With Damaged Enamel Coating And Cathodic Protection, Liang Fan, Signo Tadeu Dos Reis, Genda Chen, Michael L. Koenigstein
This paper presents the first report on the corrosion resistance of pipeline steel with damaged enamel coating and cathodic protection in 3.5 wt % NaCl solution. In particular, dual cells are set up to separate the solution in contact with the damaged and intact enamel coating areas, to produce a local corrosion resistance measurement for the first time. Enamel-coated steel samples, with two levels of cathodic protection, are tested to investigate their impedance by electrochemical impedance spectroscopy (EIS) and their cathodic current demand by a potentiostatic test. Due to its glass transition temperature, the enamel-coated pipeline can be operated on ...
Uav-Enabled Measurement For Spatial Magnetic Field Of Smart Rocks In Bridge Scour Monitoring, 2018 Missouri University of Science and Technology
Uav-Enabled Measurement For Spatial Magnetic Field Of Smart Rocks In Bridge Scour Monitoring, Genda Chen
Foundation scour is the main cause of bridge collapses in the U.S. In 2011, the principal investigator (PI) proposed smart rocks with embedded magnets for bridge scour monitoring. Once deployed around a bridge pier, smart rocks as field agents offer mission-critical information about the maximum depth of a scour hole developed around the bridge foundation – the key parameter that is used to assess foundation stability in engineering design and retrofit. Smart rocks have recently been deployed and tested at three bridge sites in California and Missouri. With multiple measurements, they can be located with an accuracy of 0.5 ...
Hyperspectral Image Analysis For Mechanical And Chemical Properties Of Concrete And Steel Surfaces, 2018 Missouri University of Science and Technology
Hyperspectral Image Analysis For Mechanical And Chemical Properties Of Concrete And Steel Surfaces, Genda Chen
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 ...
Webinar: Addressing Bicycle-Vehicle Conflicts With Alternate Signal Control Strategies, 2018 Portland State University
Webinar: Addressing Bicycle-Vehicle Conflicts With Alternate Signal Control Strategies, Sirisha Kothuri
TREC Webinar Series
There is nationwide interest in supporting sustainable and active transportation modes such as bicycling and walking due to the many benefits associated with them, including reduced congestion, lower emissions and improved health. Although the number of bicyclists is increasing, safety remains a top concern. In urban areas, a common crash type involving bicycles at intersections is the “right hook” where a right-turning vehicle collides with a through bicyclist. While geometric treatments and pavement markings have been studied, there is a lack of research on signal timing treatments to address right-hook bicycle-vehicle conflicts.
The Subject Librarian Newsletter, Engineering And Computer Science, Fall 2017, 2018 University of Central Florida
The Subject Librarian Newsletter, Engineering And Computer Science, Fall 2017, Buenaventura "Ven" Basco
Buenaventura "Ven" Basco
No abstract provided.
Adaptive Wavelet Neural Network For Terrestrial Laser Scanner-Based Crack Detection, 2018 Oregon State University
Adaptive Wavelet Neural Network For Terrestrial Laser Scanner-Based Crack Detection, Yelda Turkan, Jonathan Hong, Simon Laflamme, Nisha Puri
Civil, Construction and Environmental Engineering Publications
Objective, accurate, and fast assessment of civil infrastructure conditions is critical to timely assess safety risks. Current practices rely on visual observations and manual interpretation of reports and sketches prepared by inspectors in the field, which are labor intensive, subject to personal judgment and experience, and prone to error. Terrestrial laser scanners (TLS) are promising for automatically identifying structural condition indicators, as they are capable of providing coverage for large areas with accuracy at long ranges. Major challenges in using this technology are in storing significant amount of data and extracting appropriate features enabling condition assessment. This paper proposes a ...
Experimental Tests And Numerical Simulations For Failure Investigation On Corrugated Boxes Used On Household Appliance Packaging, Diego Fernandes Rodrigues, José Carlos Pereira
Journal of Applied Packaging Research
Packages made of corrugated paper are fundamental to the protection, transportation and handling of the appliance product market. During the storage and sales stages of a product, the package must resist compressive loads in different directions beyond moderate impacts. In this context, the objective of this work is to develop and implement a post-processor that allows the simultaneous analysis of two of the most common failure modes of packages made of corrugated paper: failure due to tensile or compressive stress limit, and failure due to local buckling, when the buckling of the faces of the corrugated paper between two peaks ...
A Deep Learning-Based Approach For Fault Diagnosis Of Roller Element Bearings, 2018 Iowa State University
A Deep Learning-Based Approach For Fault Diagnosis Of Roller Element Bearings, Mohammakazem Sadoughi, Austin Downey, Garrett Bunge, Aditya Ranawat, Chao Hu, Simon Laflamme
Civil, Construction and Environmental Engineering Conference Presentations and Proceedings
Condition monitoring and fault detection of roller element bearings is of vital importance to ensuring safe and reliable operation of rotating machinery systems. Over the past few years, convolutional neural network (CNN) has been recognized as a useful tool for fault detection of roller element bearings. Unlike the traditional fault diagnosis approaches, CNN does not require manually extracting the fault-related features from the raw sensor data and most CNN-based fault diagnosis approaches feed the raw or shallowly pre-processed data as the training/testing inputs to a CNN model, thereby avoiding the need for manual feature extraction. As such, these approaches ...
Vertical Shear Wave Velocity Profiles Generated From Spectral Analysis Of Surface Waves: Field Examples, 2018 Missouri University of Science and Technology
Vertical Shear Wave Velocity Profiles Generated From Spectral Analysis Of Surface Waves: Field Examples, Neil Lennart Anderson, Genda Chen, Siasi Kociu, Ronaldo Luna, Thanop Thitimakorn, Alexi A. Malovichko, D. Malovichko, D. Shylakov
Surface wave (Rayleigh wave) seismic data were acquired at six separate bridge sites in southeast Missouri. Each acquired surface wave data set was processed (spectral analysis of surface waves; SASW) and transformed into a site-specific vertical shear-wave velocity profile (SASW shear-wave velocity profile). The SASW shear-wave velocity profiles generated for each bridge site were compared to other geotechnical data including seismic cone penetrometer shear-wave velocity profiles, cross-borehole shear-wave velocity profiles, and borehole lithology logs. The geotechnical data presented herein indicate the SASW shear-wave velocity profiles correlate well with subsurface lithology logs and available cross-borehole shear-wave velocity control. More specifically, clays ...
Unbonded Portland Cement Concrete Overlay/Pavement Monitoring With Integrated Grating And Scattering Optical Fiber Sensors, 2018 Missouri University of Science and Technology
Unbonded Portland Cement Concrete Overlay/Pavement Monitoring With Integrated Grating And Scattering Optical Fiber Sensors, Genda Chen, Ying Huang, Yi Bao
This report summarizes the findings and results from a laboratory and field study on the strain distribution and crack development in 3" thick concrete panels cast on top of existing concrete pavements as a rapid rehabilitation strategy for roadways. Both fiber Bragg gratings (FBG) and Brillouin Optical Time Domain Reflectometry/Analysis (BOTDR/A) were applied and tested for their feasibility and effectiveness in distributed strain measurement and crack detection. For laboratory tests, six 6'×6" panels were cast similar to their corresponding field construction. Each was tested under both truck loads and under threepoint loads. The performance of distributed BOTDR ...
Temperature And Strain Measurements With Fiber Optic Sensors For Steel Beams Subjected To Fire, 2018 Missouri University of Science and Technology
Temperature And Strain Measurements With Fiber Optic Sensors For Steel Beams Subjected To Fire, Yi Bao, Yizheng Chen, Matthew S. Hoehler, Christopher M. Smith, Matthew F. Bundy, Genda Chen
This paper presents measurements of high temperatures using a Brillouin scattering based fiber optic sensor and large strains using an extrinsic Fabry-Perot interferometric sensor for assessing the thermo-mechanical behaviors of simply supported steel beams subjected to combined thermal and mechanical loading. The distributed fiber optic sensor captures detailed, non- uniform temperature distributions that are compared with thermocouple measurements resulting in an average relative difference of less than 5 % at 95 % confidence level. The extrinsic Fabry- Perot interferometric sensor captures large strains at temperatures above 1000 C. The strain results measured from the distributed fiber optic sensors and extrinsic Fabry-Perot interferometric ...
Structural Assessment Of Highway "N" Power Substation Under Earthquake Loads, 2018 Missouri University of Science and Technology
Structural Assessment Of Highway "N" Power Substation Under Earthquake Loads, Genda Chen, Dongming Yan, Zuocai Wang, Seth Justin, J. David Rogers, Kazi Rezaul Karim
In this study, the Highway N Substation was analyzed with a finite element model (FEM) for its vulnerability. The 'rigid' bus and electric switch components were characterized with full scale shake table tests. Each component of the substation was carefully modeled with due considerations of mass density, stiffness and geometries. Based on the FEM, modal analysis was conducted to identify the natural frequencies of the structure along with their corresponding mass participation factors. In response spectrum and time history analyses, the dynamic responses of main components, such as 'rigid' buses and switches, were evaluated. The magnitude and location of the ...
Strengthening Of Rural Bridges Using Rapid-Installation Frp Technology: Route 63 Bridge No. H356, Phelps County, 2018 Missouri University of Science and Technology
Strengthening Of Rural Bridges Using Rapid-Installation Frp Technology: Route 63 Bridge No. H356, Phelps County, Dongming Yan, Jianbo Li, Chenglin Bob Wu, Genda Chen
This report presents the use of externally bonded fiber reinforced polymers (FRP) laminates for the flexural strengthening of a concrete bridge. The bridge selected for this project is a two-span simply supported reinforced concrete slab with no transverse steel reinforcement located in Phelps County, MO. The original construction combined with the presence of very rigid parapets caused the formation of a 1-inch wide longitudinal crack, which resulted in the slab to behave as two separate elements. The structural behavior was verified using a finite element model (FEM) of the bridge. The bridge analysis was performed for maximum loads determined in ...
Strain Distribution And Crack Detection In Concrete Overlays With Pulse Pre-Pump Brillouin Optical Time Domain Analysis, 2018 Missouri University of Science and Technology
Strain Distribution And Crack Detection In Concrete Overlays With Pulse Pre-Pump Brillouin Optical Time Domain Analysis, Yi Bao, Genda Chen
This report is focused on the measurement of strain distributions and crack detection in unbonded and bonded pavement overlays. The main objectives of this study are: (a) to characterize the strain sensing properties of distributed fiber optic sensors with recently developed pulse pre-pump Brillouin optical time domain analysis (PPP-BOTDA), (b) to develop an installation method for real world applications, (c) to document the performance of the PPP-BOTDA technology in unbonded/bonded pavement applications, and (d) to develop a numerical model to facilitate the analysis of mechanical behavior of unbonded pavement overlay under vehicle wheel loads. A thin concrete layer can ...
Steel Building Assessment In Post-Earthquake Fire Environments With Fiber Optical Sensors, 2018 Missouri University of Science and Technology
Steel Building Assessment In Post-Earthquake Fire Environments With Fiber Optical Sensors, Genda Chen, Ying Huang, Hai Xiao
No abstract provided.
Signal Mast Arm Fatigue Failure Investigation, 2018 Missouri University of Science and Technology
Signal Mast Arm Fatigue Failure Investigation, Genda Chen, Michael G. Barker, Lokeswarappa R. Dharani, Christopher W. Ramsay
The Missouri Department of Transportation (MoDOT) has discovered and documented failures in several cantilever mast arms in the recent years. The failures were primarily by fatigue at the weld of the arm to the base plate attached to the mast. With over 6000 mast arms in service in Missouri, the failures raised concerns with the existing mast arm inventory and future mast arm design. This report presents findings from an effort to determine the cause of unexpected cracking in Missouri mast arms. Three causes of premature failure were investigated: the stress ranges experienced at the weld detail were higher than ...
Smart Rocks And Wireless Communication System For Real-Time Monitoring And Mitigation Of Bridge Scour -- A Proof-Of-Concept Study, 2018 Missouri University of Science and Technology
Smart Rocks And Wireless Communication System For Real-Time Monitoring And Mitigation Of Bridge Scour -- A Proof-Of-Concept Study, Genda Chen, David Pommerenke, Y. Rosa Zheng, Andriy V. Radchenko, Yan Tang, Brandon P. Schafer, Ying Huang, Z. L. Yang
This study aims to integrate commercial measurement and communication components into a scour monitoring system with magnets or electronics embedded in smart rocks, and evaluate and improve its performance in laboratory and field conditions for the movement of smart rocks. Properly-designed smart rocks were found to be automatically rolled into the very bottom of a scour hole and can give critical information about the maximum scour depth and effectiveness of rip-rap mitigation strategies. Four types of smart rock technologies were investigated in this proof-of-concept phase of study, including passive with embedded magnets, active with magneto-inductive communication, active with controllable magnet ...