The Effects Of Long-Duration Subduction Earthquakes On Inelastic Behavior Of Bridge Pile Foundations Subjected To Liquefaction-Induced Lateral Spreading,
2018
Atlas Geotechnical
The Effects Of Long-Duration Subduction Earthquakes On Inelastic Behavior Of Bridge Pile Foundations Subjected To Liquefaction-Induced Lateral Spreading, Jonathan Nasr, Arash Khosravifar
Civil and Environmental Engineering Faculty Publications and Presentations
Effective-stress nonlinear dynamic analyses (NDA) were performed for a large-diameter reinforced concrete (RC) pile in multi-layered liquefiable sloped ground. The objective was to assess the effects of earthquake duration on the combination of inertia and liquefaction-induced lateral spreading. A parametric study was performed using input motions from subduction and crustal earthquakes covering a wide range of motion durations. The NDA results showed that the pile head displacements increased under liquefied conditions, compared to nonliquefied conditions, due to liquefaction-induced lateral spreading. The NDA results were used to develop a displacement-based equivalent static analysis (ESA) method that combines inertial and lateral spreading …
Repairable Precast Buildings And Bridges,
2018
South Dakota State University
Repairable Precast Buildings And Bridges, Abdullah Boudaqa
Electronic Theses and Dissertations
A new moment-resisting precast connection is developed in the present work through experimental and analytical studies to accelerate construction of bridges and buildings, to improve their seismic performance, and to quickly repair them through replacement of exposed reinforcement. The new precast joint detailing incorporates (1) detachable external reinforcing steel bars restrained against buckling, which is referred to as buckling restrained reinforcement (BRR), to develop plastic bending moments, (2) a steel pipe connecting the precast members through a pin connection to resist plastic shear forces, and (3) detachable mechanical bar splices to assemble and disassemble BRR at any time specifically after …
Modified Design Procedures For Bridge Pile Foundations Subjected To Liquefaction-Induced Lateral Spreading,
2018
Portland State University
Modified Design Procedures For Bridge Pile Foundations Subjected To Liquefaction-Induced Lateral Spreading, Arash Khosravifar, Jonathan Nasr
Civil and Environmental Engineering Faculty Publications and Presentations
Effective-stress nonlinear dynamic analyses (NDA) were performed for piles in the liquefiable sloped ground to assess how inertia and liquefaction-induced lateral spreading combine in long- and short-duration motions. A parametric study was performed using input motions from subduction and crustal earthquakes covering a wide range of durations and amplitudes. The NDA results showed that the pile demands increased due to (a) longer duration shakings, and (b) liquefaction-induced lateral spreading compared to nonliquefied conditions. The NDA results were used to evaluate the accuracy of the equivalent static analysis (ESA) recommended by Caltrans/ODOT for estimating pile demands. Finally, the NDA results were …
Methodology For Load Rating Double-Tee Girder Bridges,
2018
South Dakota State University
Methodology For Load Rating Double-Tee Girder Bridges, Sandip Rimal
Electronic Theses and Dissertations
The most common type of bridge on South Dakota (SD) local roads is precast prestressed double-tee (DT) girders. More than 700 DT bridges are currently in-service in SD. Structural detailing, aging, traffic volume, and environmental conditions affect the structural performance, integrity, and capacity of DT bridges. When a bridge is affected by one or more of the aforementioned parameters, the estimation of the bridge safe live loads is necessary to ensure the safety of the traveling public and to prevent excessive bridge damage and collapse. Load rating of damaged bridges is challenging mainly because of a lack of information regarding …
Behavior Of Eb Frp Masonry Bond Under Service Temperature,
2018
Missouri University of Science and Technology
Behavior Of Eb Frp Masonry Bond Under Service Temperature, Zuhair Al-Aljaberi, John J. Myers, K. Chandrashekhara
Civil, Architectural and Environmental Engineering Faculty Research & Creative Works
The interest in advanced composites in repairing and strengthening infrastructure systems has considerably increased, especially as the application externally bonded (EB) fiber reinforced polymer (FRP) has become more well established. Previous research on bond behavior has focused on impact of durability by considering exposure to harsh environmental conditions and testing the specimens after exposure, rather than testing bond performance during exposure. The influence of directly applying temperature on bond behavior represents an open topic that needs to be investigated in more detail. This study is one of the first studies to investigate the bond behavior when the composite is subjected …
Mechanical Bar Splices For Accelerated Construction Of Bridge Columns,
2018
South Dakota State University
Mechanical Bar Splices For Accelerated Construction Of Bridge Columns, Puskar Kumar Dahal
Electronic Theses and Dissertations
Mechanical bar splicing is an alternative method of connecting reinforcing bars in concrete structures compared to conventional lap splicing mainly to reduce bar congestion in joints. Recently, mechanical bar splices, which are also referred to as bar couplers, have been used to connect precast members to accelerate construction of concrete bridges and buildings. Current codes prohibit the use of couplers in the plastic hinge regions of bridge columns in high seismic zones. This may be because of a lack of systematic test data on the coupler performance, limited experimental studies on mechanically spliced bridge columns, and an engineering precaution. The …
Cyclic Axial Compression Behavior Of Concrete-Filled Hybrid Large Rupture Strain Frp Tubes,
2018
Missouri University of Science and Technology
Cyclic Axial Compression Behavior Of Concrete-Filled Hybrid Large Rupture Strain Frp Tubes, Monika Nain
Masters Theses
"This study introduces an experimental investigation of the behavior of concrete filled fiber reinforced polymer (FRP) tubes (CFFTs) under cyclic axial compression. The FRP used in this study were either small rupture strain FRP (SRS-FRP) or large rupture strain FRP (LRS-FRP). This paper also presents the first-ever experimental study on the behavior of concrete confined using hybrid LRS-FRP and SRS-FRP. LRS-FRP included PEN (polyethylene napthalate) and PET (polyethylene terephthalate) where both of them having ultimate axial strain larger than 5%, and low stiffness. SRP-FRP included carbon and glass FRP having small rupture strains, smaller than 2%, and high stiffness. The …
Investigation Of Ribbed Dome Including Tuned Mass Damper,
2018
Old Dominion University
Investigation Of Ribbed Dome Including Tuned Mass Damper, Ali Parva
Civil & Environmental Engineering Master's Projects
This research report presents the outcome of an investigation of lightweight ribbed steel dome structure. The proposed ribbed dome structure is studied both numerically and experimentally under static, natural vibration, and base excitation conditions. The base excitation is considered in the form of a sinusoidal as well as seismic loading in the form of a scaled-down 1940 El Centro earthquake. A numerical study of the ribbed dome is also conducted including a tuned mass damper (TMD). The performance of the dome is also compared with that of a hexagonal vertical structure showing a superior response of the dome under seismic …
Building Entry Flood Barrier,
2018
The University of Akron
Building Entry Flood Barrier, Richard Esker, Shannon Mccall, Andrew Udovich, Brian Foust
Williams Honors College, Honors Research Projects
The purpose of this project is to develop a flood barrier that would resist flood water from entering through the doorways of a building. The goal is to mitigate extensive flooding within a structure. After the disastrous weather events that impacted American citizens late in the year of 2017, the team was inspired to develop a project to help disaster victims. Through extensive preliminary and market research, it was discovered that flooding is a serious issue that affects people all over the world. A product to stop flooding could benefit people in developed countries, but it could also help citizens …
Investigation Of Rapid Remote Sensing Techniques For Forensic
Wind Analyses,
2018
University of Nebraska - Lincoln
Investigation Of Rapid Remote Sensing Techniques For Forensic Wind Analyses, Yijun Liao, Richard L. Wood, Mohammad Ebrahim Mohammadi, Peter J. Hughes, J. Arn Womble
Department of Civil and Environmental Engineering: Faculty Publications
Perishable damage data resulting from severe windstorms require efficient and rapid field collection techniques. Such datasets permit forensic damage investigations and characterization of civil infrastructure. Ultimately, observed structural damage serves as a proxy approach to estimate wind speeds for storms that include hurricanes, tornadoes, straight-line winds, etc. One of the more common methods to collect, preserve, and reconstruct three-dimensional damage scenes is the use of an unmanned aerial system (UAS), commonly known as a drone. Onboard photographic payloads permit scene reconstruction via structure-from-motion; however, such approaches often require direct site access and survey points for accurate results, which limit its …
Behavior Of Cold-Formed Steel Metal Industrial
Buildings,
2018
University of Massachusetts Amherst
Behavior Of Cold-Formed Steel Metal Industrial Buildings, Adrianna M. Early, Mohammad Ebrahim Mohammadi, Richard L. Wood, Kara D. Peterma
Department of Civil and Environmental Engineering: Faculty Publications
This paper presents research focused on understanding the observed behavior of cold-formed steel (CFS) metal buildings during Hurricane Harvey, which made landfall Friday, August 25, 2017 between Port Aransas and Port O’Connor, Texas. Through the Geotechnical Extreme Event Reconnaissance (GEER) association (funded by the National Science Foundation) a team of structural engineers and researchers performed rapid and detailed assessments of structural damage caused by the hurricane. The National Science Foundation gathered photographs, damage assessments sheets, and three-dimensional laser point cloud data of severely damaged cold-formed steel industrial buildings. The Port Aransas County Airport experienced severe damage to several cold-formed steel …
Post-Earthquake Structural Damage Assessment Through Point Cloud Data,
2018
University of Nebraska-Lincoln
Post-Earthquake Structural Damage Assessment Through Point Cloud Data, Mohammad Ebrahim Mohammadi, Richard L. Wood
Department of Civil and Environmental Engineering: Faculty Publications
Structural damage assessment following an extreme event can provide valuable information and insight into unanticipated damage and failure modes to improve design philosophies and design codes as well as reduce vulnerability. Oftentimes, structural engineers create finite element models (FEM) of the structure in which numerous model parameters require calibration to simulate the current state. This information may include structural plan details (geometry), material characteristics (strength and stiffness parameters), as well as observed damage patterns (cracks, spalling, etc.). Ground-based lidar (GBL) scans and Structure-from-Motion (SfM) can rapidly capture dimensionally accurate point clouds of the structure or facility of interest. Furthermore, point …
Damage Assessment Of Built-Up Areas Via Uas-Sfm Derived Point Cloud Data,
2018
University of Nebraska - Lincoln
Damage Assessment Of Built-Up Areas Via Uas-Sfm Derived Point Cloud Data, Mohammad Ebrahim Mohammadi, Richard L. Wood
Department of Civil and Environmental Engineering: Faculty Publications
In the aftermath of extreme events (e.g., earthquakes, tsunami, tornados, etc.), rapid and reliable identification of the damage in a built-up area are crucial in to rescue, recovery, and reconstruction operations. While it is critical to conduct efficient emergency response management, lack of classified or tagged damaged regions due to communications and accessibility limitations can further delay recovery operations, rescue efforts, and resource management. Furthermore, critical and perishable damage scenes can also be lost during recovery and cleanup operations immediately following the event. In recent decades, advances in remote sensing technologies demonstrate a great potential to perform rapid reconnaissance and …
Evaluation Of The Effect Of Tack Coat Type, Application Rate, And Surface Type On Interlayer Shear Strength,
2018
South Dakota State University
Evaluation Of The Effect Of Tack Coat Type, Application Rate, And Surface Type On Interlayer Shear Strength, Chamika Prashan Dharmarathna
Electronic Theses and Dissertations
Tack coat is an asphaltic material applied between asphalt pavement layers. Since pavement is a multilayered structure, it is highly important to make proper bond between the layers to achieve a monolithic behavior. Hence, inadequate bond due to application of inadequate amount of tack coat may lead to poor structural behavior and premature failure. Also, applying excessive amount of tack coat may lead to layer slippage and binder migration. Therefore, it is highly important to apply an optimum amount of tack coat between layers. Over the past decades several studies have been conducted to determine the optimum tack coat application …
Designing And Testing 3-D Printed Wafer-Box With Embedded Pzt Sensors To Identify The Shape Effect On Energy Harvesting,
2018
Georgia Southern University
Designing And Testing 3-D Printed Wafer-Box With Embedded Pzt Sensors To Identify The Shape Effect On Energy Harvesting, Ahmad Jami Safayet
College of Graduate Studies: Theses & Dissertations
Piezoelectric energy has been recently paid attention in the field of alternative energy. Day by day the traditional energy sources including Coal tar and oils are becoming scarce. People are heading to an alternative energy source to meet the future energy demand. Piezoelectric energy is one of the competitive energy sources compared to the conventional renewable energy sources including solar, wind, and geothermal power and so on. This energy production method bears enormous research potential because it can be used as the roadway for a new method of power generation. This research project aimed to identify which shaped wafer-box produced …
Critical Buckling And Post-Buckling Behavior Of Thin-Walled Liners Encased By Underground Pipelines In Saturated Soils,
2018
Missouri University of Science and Technology
Critical Buckling And Post-Buckling Behavior Of Thin-Walled Liners Encased By Underground Pipelines In Saturated Soils, Zhaochao Li
Doctoral Dissertations
"This study aims to investigate the structural stability of thin-walled liners encased in functionally-obsolete underground pipelines in saturated soil under external hydrostatic pressure, a concentrated load, temperature change or their combination, and develop a simplified circular arch model of thin-walled liners when not constrained by the pipelines. The friction and adhesion on the interface between a liner and its constraining surface (pipeline or grouting), and the pressure gradient on deeply-buried pipelines are neglected. The critical buckling load of elastic liners is analytically derived under a plane strain condition using the principle of minimum potential energy. The analytical solution is either …
Coupling Radio Frequency Energy Via The Embedded Rebar Cage In A Reinforced Concrete Structure For The Purpose Of Concrete Degradation Sensing,
2018
University of North Florida
Coupling Radio Frequency Energy Via The Embedded Rebar Cage In A Reinforced Concrete Structure For The Purpose Of Concrete Degradation Sensing, Ryan Campiz
UNF Graduate Theses and Dissertations
This study focuses on utilizing an energy harvesting system in which a dedicated Radio Frequency (RF) power source transmits RF power via rebar in a reinforced concrete column. The RF power is received and decoupled by a receiver, and is then rectified, boosted, and stored as electrical energy in a supercapacitor, later to be used to make measurements, process data, and communicate to the source via rebar. Two design attempts are presented in this study: (a) one uses single line conduction at 2.4 GHz for RF power transfer; (b) the other uses a more conventional two-line conduction at 8.0 kHz …
Tire-Derived Geo-Cylinders And Polymer Products For Enhancing The Properties Of Base/Sub Base Materials In Pavement Systems,
2018
Structural Engineering Institute Graduate Student Chapter at WVU
Tire-Derived Geo-Cylinders And Polymer Products For Enhancing The Properties Of Base/Sub Base Materials In Pavement Systems, Justin Scott Smith
Graduate Theses, Dissertations, and Problem Reports (ETD)
As a critical part of the transportation network, pavements offer a safe means for vehicular traffic. Pavements are subjected to many forms of stress during their service life, and they are susceptible to environment related cracking and failures. Failures can be attributed to poor subgrade, freeze-thaw variations, and fatigue under repetitive axle loadings. Reinforcement products such as tire-derived geo-cylinders (TDGC) which make-up mechanical concrete and geo-polymers have been utilized in civil engineering practice, and this research aims to understand the potential life of tested pavement system components set at displacement limitations when reinforced with TDGCs and geo-polymers from exposure to …
The Determination Of The Concrete Tensile Creep At Early Age Using The Ring Test,
2018
West Virginia University
The Determination Of The Concrete Tensile Creep At Early Age Using The Ring Test, Tadamon Mohammed
Graduate Theses, Dissertations, and Problem Reports (ETD)
In this study, the modified double power law (MDPL) model is used to determine the tensile creep of concrete at an early age based on the ASTM C1581 restrained shrinkage ring test. Three concrete mixes using Ordinary Portland Cement (OPC) were tested. The three concrete mixes were cast, and each underwent the ring tests up to cracking. Mechanical properties of concrete at the age of 1, 3, 7, 14, and 28 days were tested to find the compressive strength, tensile strength and Young’s Modulus of concrete. The strength tests results were obtained from both 4x8 inch and 6x12 inch cylinders. …
Moisture Induced Deformations In Glulam Members - Experiments And 3-D Finite Element Model,
2017
Department of Structural and Construction Engineering, Collage of Engineering and Technology, University of Dar es Salaam, P.O. Box 35131 Dare es Salaam, Tanzania
Moisture Induced Deformations In Glulam Members - Experiments And 3-D Finite Element Model, Henry Meleki Kiwelu
Tanzania Journal of Engineering and Technology (TJET)
Experiments were performed on scaled glue laminated bending specimens to observe time dependent development of deformations during drying and wetting. Measurements determined changes in the average moisture content and external shape and dimensions between when specimens were placed into constant or variable climates. Alterations in the external shape and dimensions reflected changes in the average value and distribution of moisture and mechanosorptive creep in the glulam. The results are being used to develop a sequentially-coupled three-dimensional hygrothermal Finite Element (FE) model for predicting temporally varying internal strains and external deformations of drying or wetting solid wood structural components. The model …
