Workforce Development Symposiums For Uhpc,
2019
New Mexico State University
Workforce Development Symposiums For Uhpc, Brad Weldon, Craig Newtson, Grace Mcmurry, Leticia Davila
Publications
Ultra-high performance concrete (UHPC) is a cementitious material with a dense microstructure that contributes to high compressive strengths as well as enhanced durability properties. UHPC also possesses significant post-cracking strength and ductility due to the addition of fibers. These characteristics produce a material that provides advantages over conventional concrete; however, high costs attributed to materials and production, lack of industry familiarity and knowledge, and the absence of standardized design procedures have impeded its widespread use. To help disseminate knowledge on UHPC, two workforce development symposiums on UHPC were held in Las Cruces, New Mexico. The symposiums consisted of presentations and …
A Comprehensive Framework For Life-Cycle Cost Assessment Of Reinforced Concrete Bridge Decks,
2019
Oklahoma State University
A Comprehensive Framework For Life-Cycle Cost Assessment Of Reinforced Concrete Bridge Decks, Mohamed Soliman, Samir Ahmed, Ligang Shen
Publications
Various environmental and mechanical stressors cause deterioration of concrete bridge decks. Normal wear and tear, freeze and thaw cycles, and chloride penetration due to deicing salts can cause aggressive deterioration that usually require frequent interventions during the life-cycle of the bridge. These interventions include deck maintenance and repairs (e.g., application of sealers or overlay placement) as well as bridge deck replacement. The quantification of the life-cycle cost of bridge decks considering maintenance and repair activities represents a significant challenge facing local and state transportation agencies. The life-cycle maintenance activities not only increase the direct life-cycle cost of the bridge, but …
Disaster Resilient And Self-Assessing Multifunctional Transportation Structures,
2019
Texas A&M University
Disaster Resilient And Self-Assessing Multifunctional Transportation Structures, Ibrahim Karaman, Darren Hartl
Publications
This research designs and characterizes multifunctional materials, in particular inexpensive shape memory alloys, for transportation structures that possess excellent mechanical properties and self-sensing capabilities for strengthening and health monitoring. The properties are the Fe-SMAs are sensitive to part size in that the grain size of the material, which can be grown to several inches, should exceed the smallest dimension of the part. In the current work, maximum part size of the large dimension Fe-SMA rods were determined through detailed microstructural investigations. Samples were subjected to abnormal grain growth heat treatments and found out that part size be increased up to …
Structural Vulnerability Of Coastal Bridges Under Extreme Hurricane Conditions,
2019
University of Texas at San Antonio
Structural Vulnerability Of Coastal Bridges Under Extreme Hurricane Conditions, Arturo Montoya, Adolfo Matamoros, Firat Testik, Reza Nasouri, Adnan Shahriar, Arsalan Majlesi
Publications
This work presents the results of a numerical study evaluating the response of coastal bridges due to hurricane-induced waves. The analyses were conducted using the Coupled Eulerian-Lagrangian (CEL) approach, available on the commercial finite element software Abaqus, which allows modeling the interaction between water and the bridge. The work concentrated on (1) establishing an approach for modeling the desired wave characteristics (i.e., wave height, and frequency) within the CEL simulation, (2) conducting simulations using actual bridge dimensions of historically damaged bridges, (3) analyzing a range of foundation flexibilities to determine its effect on the uplift and shear forces acting on …
Probabilistic Analysis Of Slide-Rocking Structures Under Earthquake Loads,
2019
University of Nebraska-Lincoln
Probabilistic Analysis Of Slide-Rocking Structures Under Earthquake Loads, Taylor J. Knickerbocker
Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research
Estimates of rare seismic hazard are essential for the resilience of critical infrastructure and facilities. However, these estimates are highly uncertain at long return periods due to the lack of observed earthquake records. Several ground motion prediction equations have been proposed to close this gap and estimate rare seismic demands; however, these models were developed based on more moderate earthquake records and can yield physically unrealizable ground motions when extrapolated to long return periods. For this reason, seismologists have proposed using precariously balanced rocks (PBRs) as a way to constrain rare seismic hazard. PBRs are a type of fragile geologic …
Experimental Investigation Of Whitmore Section And Block Shear Failures In Steel Gusset Plates Using Digital Image Correlation,
2019
University of Texas,Tyler
Experimental Investigation Of Whitmore Section And Block Shear Failures In Steel Gusset Plates Using Digital Image Correlation, Prajwal Pokhrel
Civil Engineering Theses
Gusset plates are necessary for transferring loads from one structural member to another. During load transfer gussets can undergo shear, net section rupture and gross section yielding. Gusset design is a complex process and there is still a lack of knowledge regarding the stress and strain distribution in gusset plates. Current design practices which use Whitmore method, may not be sufficient to accurately predict the capacity of a gusset plate. An experimental study was conducted at The University of Texas at Tyler to understand the failure mechanism of gusset plates under uniaxial tensile loading. Variables considered for the experiment are …
Reliability Of Corroding Reinforced Concrete Structures,
2019
Louisiana State University and Agricultural and Mechanical College
Reliability Of Corroding Reinforced Concrete Structures, Travis Honore
LSU Master's Theses
The enhanced performance due to the addition of steel within concrete elements has thrust reinforced concrete structures to be one of the most commonly used construction materials in the world. Reinforced concrete structures are exposed to a variety of deterioration mechanisms during their operational existence, each of which contributes to reducing their service life, durability, and load bearing capacity. The longevity of these reinforced concrete structures is strongly connected to degradation processes, whose origin is environmental and/or functional. Among these processes is the initiation and evolution of corrosion on the steel reinforcement. Steel reinforcement has direct effects on the durability, …
Load Distribution Of A Prestressed Self-Consolidating Concrete Bridge,
2019
Missouri University of Science and Technology
Load Distribution Of A Prestressed Self-Consolidating Concrete Bridge, Eli S. Hernandez, John J. Myers
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
Bridge A7957 is the first Missouri Department of Transportation (MoDOT) large-scale project using self-consolidating concrete (SCC) and high-strength self-consolidating concrete (HS-SCC). The objective of this research was to monitor the initial in-service behavior of the precast-prestressed concrete primary elements of Bridge A7957 and to obtain the load distribution of the bridge using field and finite element models (FEM) data. An initial series of diagnostic load tests was conducted on the bridge superstructure. Embedded sensors recorded strain variations at different section of the instrumented girders for different load configurations. An automated total station (ATS) collected the vertical deflection of the girders …
Cost-Effective Methods To Retrofit Metal Culverts Using Composites,
2019
University of New Mexico
Cost-Effective Methods To Retrofit Metal Culverts Using Composites, Mahmoud Reda Taha, Susan Bogus Halter
Data
One of the current pressing problems for all DOTs is the corrosion-oriented deterioration of existing metal culverts. These metal culverts typically are designed for a life of 50 years. However, corrosion is making them last no longer than 30 years. A Glass Fiber Reinforced Polymers (GFRP) pipe section has been evaluated as a fit-in GFRP profile liner for complete repair and rehabilitation of the corroded metal culvert with an expected life of 75 years. This is mainly because of the corrosion free nature of the GFRP material. A comprehensive rehabilitation methodology and laboratory scale three-point bending test was conducted to …
Effect Of External Expanded Polystyrene (Eps) Panels On Slabs Subjected To Impact Load,
2019
The British University in Egypt
Effect Of External Expanded Polystyrene (Eps) Panels On Slabs Subjected To Impact Load, Yosra El Maghraby
Civil Engineering
No abstract provided.
Cost-Effective Methods To Retrofit Metal Culverts Using Composites,
2019
University of New Mexico
Cost-Effective Methods To Retrofit Metal Culverts Using Composites, Mahmoud Reda Taha, Susan Bogus Halter
Publications
One of the current pressing problems for all DOTs is the corrosion-oriented deterioration of existing metal culverts. These metal culverts typically are designed for a life of 50 years. However, corrosion is making them last no longer than 30 years. A Glass Fiber Reinforced Polymers (GFRP) pipe section has been evaluated as a fit-in GFRP profile liner for complete repair and rehabilitation of the corroded metal culvert with an expected life of 75 years. This is mainly because of the corrosion free nature of the GFRP material. A comprehensive rehabilitation methodology and laboratory scale three-point bending test was conducted to …
Experimental Study On The Effect Of Moisture On Bolt Embedment And Connection Loaded Parallel To Grain For Timber Structures,
2019
Department of Structural and Construction Engineering, Collage of Engineering and Technology, University of Dar es Salaam, P.O. Box 35131 Dare es Salaam, Tanzania
Experimental Study On The Effect Of Moisture On Bolt Embedment And Connection Loaded Parallel To Grain For Timber Structures, Henry Meleki Kiwelu
Tanzania Journal of Engineering and Technology (TJET)
Connections are critical parts of timber structures, transmitting static and dynamic forces between structural elements. The ultimate behaviour of a building depends strongly on the structural configuration and the capacity of its connections. The complete collapse of a building or other less extensive accidents that may occur usually start as a local failure inside or in the vicinity of a joint. The main aim of this study has been to investigate if the short-term capacity of steel-wood dowel joints loaded parallel to the grain is affected by variations in moisture content associated with post fabrication drying or wetting of the …
Influence Of Tempering And Cryogenic Treatment On Retained Austenite And Residual Stresses In Carbonitrided 18crnimo7-6 Low Alloy Steel,
2019
University of Dar es Salaam, Chemical and Mining Department, P.O. Box 35131, Dar es Salaam
Influence Of Tempering And Cryogenic Treatment On Retained Austenite And Residual Stresses In Carbonitrided 18crnimo7-6 Low Alloy Steel, Richard Katemi
Tanzania Journal of Engineering and Technology (TJET)
This work investigated the influence of tempering conditions coupled with cryogenic treatment on thermal stabilization of retained austenite and residual stress distributions in carbonitrided 18CrNiMo76 low alloy steel samples. The carbonitriding conditions were set to enable attaining surface carbon and nitrogen content of 0.87 and 0.34 mass.-percent respectively. After carbonitriding, some of the samples were subjected to varying tempering conditions followed by cryogenic treatment at-120 °C using nitrogen gas. Analysis of both retained austenite and residual stresses was conducted using X-ray diffraction. In the as-quenched state, carbonitrided samples contained 52 mass.-percent. Samples that were directly subjected to the cryogenic treatment …
Performance Based Design For Bridge Piers Impacted By Heavy Trucks,
2019
The City College of New York
Performance Based Design For Bridge Piers Impacted By Heavy Trucks, Anil K. Agrawal
INSPIRE Archived Webinars
Based on bridge failure data compiled by New York State Department of Transportation, collision, both caused by vessel and vehicles, is the second leading cause of bridge failures after hydraulic. Current AASHTO-LRFD (2012) recommends designing a bridge pier vulnerable to vehicular impacts for an equivalent static force of 600 kips (2,670 kN) applied in a horizontal plane at a distance of 5.0 feet above the ground level. This research presents a performance-based approach for designing a bridge pier subject to impacts by tractor-semi-trailer weighing up to 80,000 lb based on an extensive investigation using finite element model of a tractor-semitrailer …
Rubberized Chip Seal Implementation In Mid-Missouri,
2019
Missouri University of Science and Technology
Rubberized Chip Seal Implementation In Mid-Missouri, Alireza Pourhassan, Ahmed Gheni, Mohamed Elgawady
Civil, Architectural and Environmental Engineering Technical Reports
Chip seal is one of the most common and cost-effective maintenance treatment approaches to improve the life-time of pavements. Recently, the research team developed a rubberized chip seal where natural aggregate is replaced with crumb rubber obtained from recycled tires. During this study, chip seal specimens with crumb rubber and mineral aggregate were designed and constructed according to three different common methods including McLeod, Kearby, and modified Kearby.
The macrotexture of the laboratory specimens was investigated using the sand patch and image processing methods to show how each reflects on the skid resistance. The values of the mean texture depth …
Nonlinear Dynamic Analysis Of Long-Span Cable-Stayed Bridges With Train-Bridge And Cable Coupling,
2019
Central South University, China
Nonlinear Dynamic Analysis Of Long-Span Cable-Stayed Bridges With Train-Bridge And Cable Coupling, Zhihui Zhu, Lidong Wang, Michael T. Davidson, Issam E. Harik, Anand Patil
Civil Engineering Faculty Publications
Span lengths of newly constructed cable-stayed railway bridges continue to show increases relative to those of older bridges. Accompanying such increases is the importance of ensuring that vibrations of long-span cable-stayed bridges satisfy both safety and serviceability requirements, particularly for bridges that support train passages. In contrast to modern design of bridges that support roadway vehicles, current methods for analyzing cable-stayed railway bridges do not yet typically account for coupling effects that may occur between cables and the surrounding bridge structure during train passages. This paper presents a computational framework for the nonlinear dynamic analysis of railway bridges based on …
Pedestrian Bridge In Tanzania,
2019
California Polytechnic State University, San Luis Obispo
Pedestrian Bridge In Tanzania, Maja Sagaser, Karina Rosales
Architectural Engineering
This senior project originated to address the need of the community of Same, Tanzania. There is a deep and wide ravine which floods, making the path many adults and children take to the Majevu Primary School increasingly difficult and dangerous. This report encapsulates all of the steps taken to complete an approved final design for a footbridge to be constructed over this ravine. It includes the project overview, the architectural and structural design process, as well as the important considerations. There are also structural drawings that include plans, elevations, and details.
Steel Test Set-Up For Non-Ductile Concrete Shear Walls,
2019
California Polytechnic State University, San Luis Obispo
Steel Test Set-Up For Non-Ductile Concrete Shear Walls, Colin S. Ridgley
Architectural Engineering
The purpose of this project was to provide a robust test set-up for the thesis work being conducted by graduate students, Jerry Luong & Rory de Sevilla. Their research aims to evaluate the feasibility of using fiber-reinforced polymer wraps and splay anchors to retrofit non-ductile concrete shear walls through a series of tests on reinforced concrete walls.
Four key constraints governed the design of the test set-up. First, the wall can be cyclically, laterally loaded to develop data for comparison with theoretical analysis methods. Second, the wall can be axially loaded to simulate interaction effects and prevent a sliding failure …
In-Plane Cyclic Behavior Of A Steel Mesh Reinforced Cob Wall,
2019
California Polytechnic State University, San Luis Obispo
In-Plane Cyclic Behavior Of A Steel Mesh Reinforced Cob Wall, Julia Fremuth Sargent
Master's Theses
This thesis presents the results from in-plane cyclic testing of a reinforced cob wall. Cob is an earthen building material composed of sand, clay, straw and water. Cob is typically constructed with no steel reinforcement; however, the California Building Code requires reinforcement in all buildings for resisting seismic forces. The purpose of this thesis is to provide additional technical data to integrate cob into the building code.
Test results are reported for a 7’ x 8’ x 14” wall with two layers of welded wire steel reinforcement constructed on a reinforced concrete foundation. In-plane cyclic loading was performed on the …
Detection Of Sand Boils From Images Using Machine Learning Approaches,
2019
University of New Orleans
Detection Of Sand Boils From Images Using Machine Learning Approaches, Aditi S. Kuchi
LSU New Orleans Theses and Dissertations
Levees provide protection for vast amounts of commercial and residential properties. However, these structures degrade over time, due to the impact of severe weather, sand boils, subsidence of land, seepage, etc. In this research, we focus on detecting sand boils. Sand boils occur when water under pressure wells up to the surface through a bed of sand. These make levees especially vulnerable. Object detection is a good approach to confirm the presence of sand boils from satellite or drone imagery, which can be utilized to assist in the automated levee monitoring methodology. Since sand boils have distinct features, applying object …
