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Articles 1 - 30 of 204
Full-Text Articles in Entire DC Network
Low-Cement Concrete Mixture For Bridge Decks And Rails, Soumitra Das, George Morcous Ph.D., Jiong Hu
Low-Cement Concrete Mixture For Bridge Decks And Rails, Soumitra Das, George Morcous Ph.D., Jiong Hu
Nebraska Department of Transportation: Research Reports
Right after construction, drying shrinkage of restrained concrete bridge decks and rails causes early-age cracking, insertion of water and chemicals, and corrosion of reinforcing steel that eventually leads to delamination and spalling of concrete. The main objective of this research is to control early-age shrinkage cracking by reducing cementitious material content in bridge deck and rail concrete mixtures. Several reduced cementitious materials concrete (RCMC) mixtures were developed by optimizing aggregate particle packing and conducting overall performance evaluation. This evaluation was carried out in three phases. The first phase investigated the feasibility of new RCMC mixtures by testing workability, compressive strength, …
Load Determination, Strengthening, And Behavior Study Of Prestressed Concrete Channel Bridge Girders In South Carolina, Elhussien Khaled Elbatanouny
Load Determination, Strengthening, And Behavior Study Of Prestressed Concrete Channel Bridge Girders In South Carolina, Elhussien Khaled Elbatanouny
Theses and Dissertations
The South Carolina Department of Transportation (SCDOT) is currently engaged in a multi-year effort to assess the structural integrity of its inventory of over 9,000 bridges. This assessment process is expected to result in an increase in the number of bridges that require load postings, repairs, or replacements across South Carolina. This could potentially lead to adverse economic repercussions due to restricted truck routes, bridge closures, repair work, and the need for bridge replacements. To alleviate the escalating costs associated with these challenges, it is imperative to explore methods aimed at reducing the need for load postings and bridge closures …
Tehachapi Mountain Trail Association – Trail Bridge Construction, Michael Bowman
Tehachapi Mountain Trail Association – Trail Bridge Construction, Michael Bowman
Construction Management
The Tehachapi Mountain Trail Association is a nonprofit organization which operates 32 miles of hiking and mountain biking trails year-round. The 650-acre property is located in the foothills above Tehachapi, CA and offers local residents and enthusiasts from around the area an area to exercise and enjoy nature. TMTA is able to operate through yearly memberships that allow the association to hold insurance as well as continue to maintain and build new trails year-round. After completing a separate project for TMTA in Winter 2022 for CM 420 Construction Service Learning, the President, Brandon Griffiths approached me with the idea of …
Assessment Of Bridge Pier Response To Fire, Vehicle Impact, And Air Blast, Chen Fang, Qusai Alomari, Daniel G. Linzell
Assessment Of Bridge Pier Response To Fire, Vehicle Impact, And Air Blast, Chen Fang, Qusai Alomari, Daniel G. Linzell
Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research
Highway bridges exposed to intentional or unintentional fire followed by combined vehicle impact and air blast are at risk of significant damage and, possibly, collapse. Limited studies examining the complex effects of these extreme demands on bridge support elements and parametrizing their response and damage are found in the open literature. Research that is presented is part of an ongoing numerical investigation examining round, multi-column, reinforced concrete (RC), bridge pier behavior subject to multi-hazard scenarios involving fire, vehicle impact, and air blast. Detailed nonlinear finite element analysis models of single columns and multi-column piers supported by a pile foundation system …
Fatigue Performance Of Flexural Retrofits For Precast Slab Bridges, Ian Stewart
Fatigue Performance Of Flexural Retrofits For Precast Slab Bridges, Ian Stewart
All Theses
This thesis discusses flexural and cyclic load testing of two potential retrofits for pre-cast slab bridges. These slabs came from South Carolina Department of Transportation (SCDOT) decommissioned bridges as a part of an ongoing project with SCDOT. The first is a Carbon Fiber Reinforced Plate (CFRP) retrofit where four CFRP plates were adhesively bonded to the bottom of a slab. The second is a steel plate that was mechanically attached to the bottom of a slab using bolted connections. The bolts were cast into grouted holes in the slab. To better understand the failure mode of these retrofits and their …
Uhpc Decked I-Beam For Accelerated Bridge Construction, George Morcous, Maher K. Tadros
Uhpc Decked I-Beam For Accelerated Bridge Construction, George Morcous, Maher K. Tadros
Nebraska Department of Transportation: Research Reports
Ultra-High-Performance Concrete (UHPC) is an excellent material for bridge construction due to its exceptional durability and superior mechanical properties. Several Departments of Transportations (DOTs), including NDOT, have limited the use of UHPC in bridge construction to joints and connections between bridge components due to the relatively high materials cost of commercially UHPC products. Recently, NDOT has sponsored a research project to develop a non-proprietary UHPC using local materials to reduce materials cost and ensure its availability to local contractors and precast producers. The project was completed successfully and an economical UHPC mix that satisfied all workability, durability, and strength requirements …
Sensor Equipped Uas For Non-Contact Bridge Inspections: Field Application, Roya Nasimi, Fernando Moreu, G. Matthew Fricke
Sensor Equipped Uas For Non-Contact Bridge Inspections: Field Application, Roya Nasimi, Fernando Moreu, G. Matthew Fricke
Department of Civil and Environmental Engineering: Faculty Publications
In the future, sensors mounted on uncrewed aerial systems (UASs) will play a critical role in increasing both the speed and safety of structural inspections. Environmental and safety concerns make structural inspections and maintenance challenging when conducted using traditional methods, especially for large structures. The methods developed and tested in the laboratory need to be tested in the field on real-size structures to identify their potential for full implementation. This paper presents results from a full-scale field implementation of a novel sensor equipped with UAS to measure non-contact transverse displacement from a pedestrian bridge. To this end, the authors modified …
Damage Detection And Damage Localization In Bridges With Low-Density Instrumentations Using The Wave-Method: Application To A Shake-Table Tested Bridge, Mehran Rahmani, Xintong Ji, Sovann Reach Kiet
Damage Detection And Damage Localization In Bridges With Low-Density Instrumentations Using The Wave-Method: Application To A Shake-Table Tested Bridge, Mehran Rahmani, Xintong Ji, Sovann Reach Kiet
Mineta Transportation Institute
This study presents a major development to the wave method, a methodology used for structural identification and monitoring. The research team tested the method for use in structural damage detection and damage localization in bridges, the latter being a challenging task. The main goal was to assess capability of the improved method by applying it to a shake-table-tested prototype bridge with sparse instrumentation. The bridge was a 4-span reinforced concrete structure comprising two columns at each bent (6 columns total) and a flat slab. It was tested to failure using seven biaxial excitations at its base. Availability of a robust …
Dataset For Large-Scale, Lateral-Torsional Buckling Tests Of Continuous Beams In A Grillage System, Ahmed Rageh, C. Shawn Sun, Daniel G. Linzell, Jay A. Puckett
Dataset For Large-Scale, Lateral-Torsional Buckling Tests Of Continuous Beams In A Grillage System, Ahmed Rageh, C. Shawn Sun, Daniel G. Linzell, Jay A. Puckett
Department of Civil and Environmental Engineering: Faculty Publications
A number of large-scale tests of a grillage system are summarized and reduced data are provided. The tests were completed in association with a Louisiana Transportation Research Center (LTRC) project for the Louisiana Department of Transportation and Development (LA DOTD) whose goal was to better quantify behavior and limit states of steel bridge floor systems to refine longitudinal member (stringer) load- rating calculations. A number of tests focused on the behavior of the stringers resting on transverse members (a floorbeam), a system akin to a grillage. The system was proportioned with the expectation that stringer lateral-torsional buckling, a key steel …
Phased Construction Bridges: Monitoring And Analysis For Traffic-Induced Vibration, Khalid Al-Kady, Christine E. Wittich, Richard L. Wood, George Morcous
Phased Construction Bridges: Monitoring And Analysis For Traffic-Induced Vibration, Khalid Al-Kady, Christine E. Wittich, Richard L. Wood, George Morcous
Nebraska Department of Transportation: Research Reports
Phased construction is a common technique utilized to allow bridges to remain partially open to traffic throughout the construction process. The segment of the bridge deck that is constructed second cures under the effect of traffic-induced vibration transmitted from the adjacent bridge-deck segment, which is open to traffic. However, subjecting bridge decks to traffic-induced vibration during early-age curing raises concerns about the durability of the decks. The primary goal of this study is to generate a fundamental understanding of the transmission of traffic-induced vibration, the extent of degradation on phased construction bridge decks, and the impact of potential mitigation measures. …
Bridge Project Prioritization, Bryan Gibson, Christopher Van Dyke, Sudhir Palle, Ryan Griffith, Doug Kreis
Bridge Project Prioritization, Bryan Gibson, Christopher Van Dyke, Sudhir Palle, Ryan Griffith, Doug Kreis
Kentucky Transportation Center Research Report
Kentucky’s 14,000+ bridges are key nodes within the state’s surface transportation network. They facilitate the movement of freight, commercial vehicles, and personal vehicles alike. Historically, the Kentucky Transportation Cabinet (KYTC) has prioritized bridge maintenance projects using sufficiency ratings. These ratings are based on three factors — structural adequacy and safety, design obsolescence, and an asset’s importance within the roadway network. Although useful, sufficiency ratings do not account for factors that should be considered during the prioritization process (e.g., condition factors, risk). To address the shortcomings associated with using sufficiency ratings, KYTC — with the assistance of the Kentucky Transportation Center …
Updating The Bridge Construction Cost Database, Rachel Catchings, Ying Li, Ryan Griffith, Sudhir Palle
Updating The Bridge Construction Cost Database, Rachel Catchings, Ying Li, Ryan Griffith, Sudhir Palle
Kentucky Transportation Center Research Report
Adopting a comprehensive suite of methods to track, analyze, and maintain data on bridge construction costs can help state transportation agencies identify and implement strategies to mitigate the influence of factors which escalate project costs. This report discusses how the Kentucky Transportation Cabinet (KYTC) should approach updating, maintaining, and analyzing its bridge construction cost data. Based on a review of practices introduced at other agencies and interviews with public and private industry stakeholders, the report catalogues practical strategies for improving estimating procedures and tracking cost data as well as the most important cost drivers of bridge construction. Analysis of KYTC …
San Luis Obispo Botanical Garden Bridge Rebuild, Anthony T. Flores
San Luis Obispo Botanical Garden Bridge Rebuild, Anthony T. Flores
Construction Management
This paper will outline the process of designing, deconstructing, and reconstructing a utility bridge at the San Luis Obispo Botanical Garden. The San Luis Obispo Botanical Garden’s entrance was recently changed deeper into the property. The old entrance was at the front and was home to a bridge utilized by staff, volunteers, and visitors alike. This project’s goal was to rebuild the utility bridge so that it could be used by the facilities staff and volunteers when working on property. There was one student involved in this project who acted as the designer, performed the preconstruction work, and constructed the …
A Physical Model Of Deadmans Run, Quinn Brandt
A Physical Model Of Deadmans Run, Quinn Brandt
Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research
A physical model of Deadmans Run and a pair of railroad bridges was constructed to assess the impacts of the bridges on flood flows. Lower Platte South Natural Resources District is planning a series of improvements to Deadmans Run to improve flood conveyance capacity and remove approximately 500 homes and businesses from the floodplain. The rail bridges are located less than a mile from the confluence of Deadmans Run and Salt Creek, meaning the bridges present a significant bottleneck to the planned improvements. The physical model was used to characterize the drag effects caused by the bridges, which was used …
Evaluating The Effects Of Shored Construction On Steel Girder Composite Bridges, Parker Brooks
Evaluating The Effects Of Shored Construction On Steel Girder Composite Bridges, Parker Brooks
Doctoral Dissertations and Master's Theses
Steel composite girder bridges provide economic advantages and higher load-carrying capacity than non-composite alternatives. Over the years, a conventional sequence of un-shored construction for steel girder composite bridges has been developed. There is an alternative construction sequence, known as shored construction, that uses temporary supports (discretely or fully supported) for the superstructure during the installation of metal forms and the pouring of concrete. Shored construction also can be used in an Accelerated Bridge Construction (ABC) practice where construction occurs at a nearby site and fully-formed elements are transported to the final site using self-propelled modular transporters (SPMTs). In order to …
Estimation Of The Service Life Of Span Structures In Predicting The Durability Of Reinforced Concrete Bridges, Sh.B. Akhmedov, Kh. Almenov, Sh.Sh. Shojalilov, Sh.Sh. Safarov
Estimation Of The Service Life Of Span Structures In Predicting The Durability Of Reinforced Concrete Bridges, Sh.B. Akhmedov, Kh. Almenov, Sh.Sh. Shojalilov, Sh.Sh. Safarov
The Scientific Journal of Vehicles and Roads
In recent years, on the roads of Uzbekistan and other countries, there has been a dangerous increase in various damages in the operated superstructures, caused by an increase in the service life and traffic intensity of vehicles and cargo tension.
Design And Detailing Of Cast-In-Place And Precast Concrete Approach Slabs, George Morcous, Mostafa Abo-Elkhier
Design And Detailing Of Cast-In-Place And Precast Concrete Approach Slabs, George Morcous, Mostafa Abo-Elkhier
Nebraska Department of Transportation: Research Reports
Approach slab is a structural concrete slab that spans from the backwall of the abutment (i.e. end of the bridge floor) to the beginning of the paving section. The purpose of the approach slab is to carry the traffic loads over the backfill behind the abutments to avoid differential settlement that causes bumps at the bridge ends. Cast- in-place concrete approach slab is the current practice in US with various spans, reinforcement, thicknesses, joints, and concrete covers. NDOT has observed premature cracking in a significant number of approach slabs, which could result in a shorter service life and costly repairs/replacements …
Bridge Prioritization And Preservation Along Route 66, Sarah Ballard
Bridge Prioritization And Preservation Along Route 66, Sarah Ballard
Open Access Theses & Dissertations
Eligible bridges around the United States receive federal funding every year for replacement or rehabilitation. The main criterion for allocation of this funding is based on engineering aspects (e.g., life safety, condition, functionality), often leaving the historical value of the bridge at the bottom of the importance level. One of the main historical roads known in America is Route 66, also known as the â??Mother Road.â?? This route was the road to opportunity in the 1930s. Many bridges with historical significance carry the route and represent an integral part of the history of the Mother Road. This research analyzes bridges …
Structural Identification And Damage Detection In Bridges Using Wave Method And Uniform Shear Beam Models: A Feasibility Study, Mehran Rahmani, Manan Naik
Structural Identification And Damage Detection In Bridges Using Wave Method And Uniform Shear Beam Models: A Feasibility Study, Mehran Rahmani, Manan Naik
Mineta Transportation Institute
This report presents a wave method to be used for the structural identification and damage detection of structural components in bridges, e.g., bridge piers. This method has proven to be promising when applied to real structures and large amplitude responses in buildings (e.g., mid-rise and high-rise buildings). This study is the first application of the method to damaged bridge structures. The bridge identification was performed using wave propagation in a simple uniform shear beam model. The method identifies a wave velocity for the structure by fitting an equivalent uniform shear beam model to the impulse response functions of the recorded …
Hydraulic Balsa Wood Rising Bridge, Kaitlyn Greenfield
Hydraulic Balsa Wood Rising Bridge, Kaitlyn Greenfield
All Undergraduate Projects
What is the solution to allowing tall vessels to navigate past a vehicle bridge that is less than 10 [ft] above the water? To answer this question, a balsa wood bridge was designed, constructed, and tested. The bridge needed to articulate by mechanical means, allow for travel through the bridge, and be able to withstand ample force while the main structure only being constructed of balsa wood and glue. The project was analyzed in sections. These sections include: the bridge structure and its members, the hydraulic lift, and the pins needed for the bridge and hydraulic lift to operate. The …
An Analysis Of A Hybrid Steel Bridge, Andrew Iglehart
An Analysis Of A Hybrid Steel Bridge, Andrew Iglehart
Mahurin Honors College Capstone Experience/Thesis Projects
The American Institute of Steel Construction hosts a competition for graduating college seniors each year. The competition is designing and fabricating a scaled steel bridge within certain parameters. Each year the parameters change to allow different seniors to face similar challenges without copying the previous year’s work. Before the outbreak of COVID-19, a bridge was fabricated as per the rules in the 2020, and the same bridge was used for the 2021 competition. With a bridge already fabricated and being used for the competition, a question arose about analyzing the bridge.
This thesis encompasses the entire analysis of the steel …
Studies On Tornado-Structure Interactions And Guidance On Design Tornadic Wind Loading, Zhi Li
Studies On Tornado-Structure Interactions And Guidance On Design Tornadic Wind Loading, Zhi Li
Doctoral Dissertations
“Tornadoes are violent natural hazards that could caused significant property loss and fatalities. Statistical data indicates that most fatalities during tornado incidents were caused by the building failure under tornadoes. For example, in the 2011 Joplin Tornado, 161 people were killed, and 84 percent of the fatalities were related to the failure of buildings. In addition, most of the significant, tornado-induced property loss and fatalities are relevant to the tornadoes passing through the densely populated regions. Besides buildings, bridges were also severely damaged or destroyed by tornadoes in the United States. To reduce the tornado-induced loss, it is imperative to …
Lessons Learned From Six Different Structural Health Monitoring Systems On Highway Bridges, Abheetha Peiris, Charlie Sun, Issam E. Harik
Lessons Learned From Six Different Structural Health Monitoring Systems On Highway Bridges, Abheetha Peiris, Charlie Sun, Issam E. Harik
Kentucky Transportation Center Faculty and Researcher Publications
Structural health monitoring has been utilized in numerous ways to investigate the performance and integrity of highway bridges. This paper highlights the use of six structural health monitoring systems, which were deployed to monitor distinct behaviors on six bridges in Kentucky. The structural health monitoring systems are as follows: (1) Over-height truck impact detection and monitoring on the I-64 over US 60 bridge, (2) Barge impact detection and monitoring on northbound US 41 over the Ohio River, (3) effectiveness of carbon fiber-reinforced polymer retrofit evaluation based on prestressed concrete I-girder crack movement on the I-65 elevated expressway in Louisville, (4) …
Wooden Bridge Demolition And Reconstruction, Josh Simon Rogers
Wooden Bridge Demolition And Reconstruction, Josh Simon Rogers
Construction Management
The Conejo Recreation and Park District (CRPD) is a nonprofit city government organization that maintains the parks and hiking trails in Thousand Oaks, California. They were informed that one of the bridges at the Stagecoach Inn, a landmark park located in Thousand Oaks California, was old and sagging in a way that made interfered with the flow of the creek it spanned over. A plan to demolish the current bridge was created. Utilizing ArchiCAD and Microsoft Excel a design and an estimate were developed for a new bridge that would be built in its place. This bridge would be tall …
Construction Of The Slo Botanical Gardens Foot Bridge - Interdisciplinary Project, Connor N. Layman
Construction Of The Slo Botanical Gardens Foot Bridge - Interdisciplinary Project, Connor N. Layman
Construction Management
In the Winter quarter of 2020, a project based senior project was sought out by a Cal Poly Construction Management student, and he was connected with the San Luis Obispo Botanical Gardens (SLO BG). SLO BG is a non-profit organization located on 150 acres in the El Chorro Regional Park. After meeting with the SLO BG staff and exploring their many needed projects, the student and the staff mutually concluded that he would build a bridge and accompanying stairs which resided on a well-traveled trail on the property. He successfully developed the project schedule, budget, recruited an architect for design …
Load Truncation Approach For Development Of Live Load Factors For Bridge Rating, Sasan Siavashi, Christopher D. Eamon
Load Truncation Approach For Development Of Live Load Factors For Bridge Rating, Sasan Siavashi, Christopher D. Eamon
Civil and Environmental Engineering Faculty Research Publications
Various local governments have developed state-specific vehicular live load factors for bridge rating. However, a significant computational demand is often associated with such an effort. This is due to the large size of the weigh-in-motion (WIM) databases frequently used in the procedure. In this study, a method is proposed that can significantly reduce the computational cost of the analysis, while still maintaining reasonable accuracy. The proposed approach develops approximate live load random variable statistics by truncating the WIM database based on gross vehicle weight, then a complete reliability analysis is conducted to develop new live load factors that meet AASHTO-specified …
Application Of Internal Curing To Improve Concrete Bridge Deck Performance, Arman Abdigaliyev, Yong-Rak Kim, Jiong Hu
Application Of Internal Curing To Improve Concrete Bridge Deck Performance, Arman Abdigaliyev, Yong-Rak Kim, Jiong Hu
Nebraska Department of Transportation: Research Reports
Due to the relatively high cement content and low water-to-cement ratio (w/c) used, bridge deck concrete is prone to premature cracking. Internal curing has been found to greatly reduce the chance of premature cracking as well as concrete deterioration. This research project was intended to develop internally cured bridge deck concrete based on a local mix design in Nebraska. Four different lightweight fine aggregate (LWFA) as internal curing agents were evaluated, and their effects on fresh, mechanical, durability, and shrinkage properties of concrete were studied. To identify the most effective LWFA dosage for shrinkage reduction, different replacement rates of sand …
Bridge Resilience Assessment With Inspire Data, Iris Tien, Yijian Zhang
Bridge Resilience Assessment With Inspire Data, Iris Tien, Yijian Zhang
Project RR-1
This project proposed a methodology to assess the impact of corrosion on the performance of bridges. The combined analytical and numerical modeling of shear-critical and lap-spliced columns is detailed, and outcomes are verified with previous experimental test data. The impact of corrosion on risk is assessed through conducting fragility analyses. Results quantify the increase in failure probabilities of these structures, measured by increasing probabilities of exceeding defined damage states, with increasing levels of corrosion. Corrosion is found to have a larger impact on increasing probabilities of exceeding more severe damage states. Twenty percent mass loss of reinforcement increases the probability …
Uav-Enabled Measurement For Spatial Magnetic Field Of Smart Rocks In Bridge Scour Monitoring -- Technical Report (2017-2020), Genda Chen, Haibin Zhang, Zhaochao Li
Uav-Enabled Measurement For Spatial Magnetic Field Of Smart Rocks In Bridge Scour Monitoring -- Technical Report (2017-2020), Genda Chen, Haibin Zhang, Zhaochao Li
Project SN-1
This project proposed an unmanned aerial vehicle (UAV)-based method to measure the change in magnetic field as a result of the movement of a smart rock to monitor the maximum depth of bridge scour. A high resolution 3-axis magnetometer and global positioning system (GPS) unit were installed on the UAV to obtain the magnetic field intensity and its corresponding coordinate. The optimization algorithm for the localization of smart rock was demonstrated and adopted. The impact factors on accurate smart rock positioning were experimentally investigated. Utilizing finite element method, the influence of steel reinforcing bars on the distribution of ambient magnetic …
Development Of An Ndt Tool For In-Situ Assessment Of Prestress Loss, Bibo Zhong, Jinying Zhu, George Morcous
Development Of An Ndt Tool For In-Situ Assessment Of Prestress Loss, Bibo Zhong, Jinying Zhu, George Morcous
Nebraska Department of Transportation: Research Reports
The research objective is to develop a non-destructive testing (NDT) method to evaluate the prestress loss in prestressed concrete bridge girders using ultrasonic waves. The work principle is based on acoustoelastic effect - ultrasonic wave velocity varies with stress level in prestressed concrete. A self-reference test setup was proposed to measure wave velocity in two orthogonal directions (prestress and unstressed directions) in the girder. This setup will be able to reduce effects of material variation and temperature change.
The concept was first validated on small concrete specimens (cylinders and beams) in laboratory. A signal analysis algorithm was developed to reliably …