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Articles 1081 - 1110 of 4011
Full-Text Articles in Civil and Environmental Engineering
Pedestrian Bridge In Tanzania, Maja Sagaser, Karina Rosales
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, Colin S. Ridgley
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, Julia Fremuth Sargent
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, Aditi S. Kuchi
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 …
Proposed New Military Live Load For Highway Bridges In The United States, Walter P. Parker
Proposed New Military Live Load For Highway Bridges In The United States, Walter P. Parker
LSU New Orleans Theses and Dissertations
This thesis presents the results of a mathematical analysis of various live load combinations on highway bridge spans up to 304.8 meters (1,000 feet) total lengths. The analysis included continuous beams, but only the results for simple beams is presented. The analysis was performed using an independently developed Microsoft EXCEL spreadsheet computation, based on superposition and classical mechanics.
In this thesis, several actual bridge live loadings and several hypothetical live loadings were analyzed and compared to the American Association of State Highway and Transportation Officials Load and Resistance Factor Design method. Also considered was the new bridge design method adopted …
Advanced Removal Of 4-Nitrophenol By Emerging And Intensifying Technology Of Emulsion Liquid Membrane With Magnetic Nanoparticles, Qusay Al-Obaidi, Muthanna H. Al-Dahhan
Advanced Removal Of 4-Nitrophenol By Emerging And Intensifying Technology Of Emulsion Liquid Membrane With Magnetic Nanoparticles, Qusay Al-Obaidi, Muthanna H. Al-Dahhan
Chemical and Biochemical Engineering Faculty Research & Creative Works
4-nitrophenol is one of the phenolic compounds found in industrial wastes that needs to be removed from treated wastewater. Emulsion liquid membrane (ELM) has been introduced as a developing technology for advanced wastewater and water treatment. This emerging technology of treatment can be intensified by strategically adding nanoparticles to organic membrane phase (O). To facilitate the industrial implementation of ELM with nanoparticles, we used magnetic iron nanoparticles added to the organic phase (O) in order to recover them by a magnet for reuse. This also assists in de-emulsification step. The results show that with the use of 1% (W/W) of …
Validation Of The State Based Peridynamic Lattice Model, Anima Bista
Validation Of The State Based Peridynamic Lattice Model, Anima Bista
Civil Engineering ETDs
This thesis presents a study performed to validate the State-based Peridynamic Lattice Model (SPLM) using results obtained from laboratory experiments. The SPLM is capable of modeling cracking of solids using particle lattices. We use a plane stress, elastic-plastic damage SPLM model for the simulations. The SPLM model is appropriate for computational simulations of cementitious materials as it automatically allows cracks to develop. In this study, the lattices are rotated through different angles and the variations of the cracking patterns are studied. In the laboratory, we performed nine Brazilian split cylinder tests, three anchor pullout/direct tensile tests, and eight compression tests …
Development Of A Mechanical Device For Measuring Connection Rotations During Seismic Loading, Garrett Tatum
Development Of A Mechanical Device For Measuring Connection Rotations During Seismic Loading, Garrett Tatum
Civil Engineering Undergraduate Honors Theses
This engineering design project sought to design a cheap and easy-to-use sensor to monitor seismic connection rotations in steel buildings during earthquakes by using a linear ratchet mechanism. The idea for the project goes against the mainstream of research that is seeking to develop complex digital networks for monitoring structures in earthquake regions. Whereas many modern sensor networks require high-cost, professionally maintained digital networks, an analog sensor could provide much of the same information at a fraction of the cost, allowing sensors to be more widely utilized, particularly in developing countries. This project required an iterative engineering design process to …
Point Cloud Technology For Analysis Of Existing Structures, Jacob Cano
Point Cloud Technology For Analysis Of Existing Structures, Jacob Cano
Electronic Theses and Dissertations
For this thesis, a study was completed on two different structures on the UCF Orlando campus through the use of both structural plans and point cloud technology. The results sought to understand the viability of point cloud technology as an accurate tool for the static and dynamic modal analysis of existing structures. For static analysis, a portion of the framing of Spectrum Stadium was rendered, modeled, analyzed and compared to a previous case study. The results emphasized how different users can render dissimilar member sizes and lengths due to human judgment on point cloud visuals. The study also found that …
In-Situ Field Monitoring Of A Uhpc And Hpc Bridge Superstructure Under Diagnostic Load Testing Using Digital Image Correlation, Prajwol Sharma
In-Situ Field Monitoring Of A Uhpc And Hpc Bridge Superstructure Under Diagnostic Load Testing Using Digital Image Correlation, Prajwol Sharma
Civil Engineering Theses
New innovative methods of bridge design are being sought to increase the service life of these structure. High Performance Concrete (HPC) and Ultra-High-Performance Concrete (UHPC) utilizes a mix of high strength concrete with steel fibers to create a strong and ductile reinforced concrete mix. While not new to civil engineering construction, this material still has some uncertainty of its performance both long and short term. As a result, in-situ experimental monitoring is important to verify methods of design and the suitability of the materials. A two-span pre-stressed UHPC and HPC reinforced concrete bridge superstructure was designed at New Mexico State …
Investigation Of Flexural Behavior Of Steel Fiber Reinforced Concrete And Steel Fiber Orientation Control During Construction, Maria Kolisnichenko
Investigation Of Flexural Behavior Of Steel Fiber Reinforced Concrete And Steel Fiber Orientation Control During Construction, Maria Kolisnichenko
Electronic Theses and Dissertations
Concrete is the most widely used construction material in the world, and its consumption has been increasing. The main benefits of concrete include its durability, availability of the components, and great strength in compression. Despite all these advantages, however, concrete is a brittle material with a relatively low tensile strength and deformation capacity. It is, therefore, vulnerable to cracking under tension, which can lead to sudden catastrophic failures of concrete structures. In order to control and reduce cracking, reinforcement of concrete is necessary.
The most commonly used reinforcement technique in structural application is the use of deformed steel bars. However, …
The Influence Of Citric Acid On Setting Time And Temperature Behavior Of Calcium Sulfoaluminate-Belite Cement, Edgar Soriano
The Influence Of Citric Acid On Setting Time And Temperature Behavior Of Calcium Sulfoaluminate-Belite Cement, Edgar Soriano
Civil Engineering Undergraduate Honors Theses
Today the need to opt for alternative cementitious materials is growing due to environmental reasons and construction time frames that portland cement cannot always satisfy. Calcium Sulfoaluminate (CSA) cements are a strong candidate to supplement or replace portland cement in the construction field for certain applications. In the United States, CSA cement has been limited mostly to pavement repairs because of its rapid initial setting time. The chemical compound responsible for this phenomenon is the alumina. This compound and sulfate are present in larger proportions compared to portland cement. The purpose of this research is to study how the use …
Tension Splitting Strength Of Bcsa Concrete Cylinders, Andrew Steven Deschenes
Tension Splitting Strength Of Bcsa Concrete Cylinders, Andrew Steven Deschenes
Civil Engineering Undergraduate Honors Theses
The focus of this research was to compare the tension splitting strength (TSS) of belitic calcium sufloaluminate (BCSA) cement concrete to tensile strength predicted by the American Concrete Institute (ACI) and to similarly proportioned portland cement (PC) concrete. BCSA is a rapid-setting cement with higher early strength, higher ettringite content, and lower calcium silicate hydrate (C-S-H) content than PC. PC and BCSA cement concrete cylinders were broken at different ages in both uniaxial compression and TSS. It was found that BCSA had a similar TSS to both the ACI prediction and PC TSS, but the results require further testing for …
Turbulent Effects On Building Pressure Using A Two-Dimensional Finite Element Program, Jonese Woods
Turbulent Effects On Building Pressure Using A Two-Dimensional Finite Element Program, Jonese Woods
Civil Engineering Undergraduate Honors Theses
Much of the knowledge about building aerodynamics today was obtained from physical testing like wind tunnel testing. Physical testing is time-consuming and very expensive. As a result, computational methods like the finite element method are being explored for use in building aerodynamics. Despite several years of research, there is still not a clear understanding of the peak pressure on buildings due to turbulence. Many of the research thus far has focused on comparing different computational methods. However, much work is needed in understanding the capability of the individual methods. In this work, a two-dimensional finite element program is used to …
Program Progress Performance Report #4, Missouri University Of Science And Technology. Inspire - University Transportation Center
Program Progress Performance Report #4, Missouri University Of Science And Technology. Inspire - University Transportation Center
Semi-Annual Progress Reports
No abstract provided.
Urban Underground Infrastructure Monitoring Iot: The Path Loss Analysis, Abdul Salam, Syed Shah
Urban Underground Infrastructure Monitoring Iot: The Path Loss Analysis, Abdul Salam, Syed Shah
Faculty Publications
The extra quantities of wastewater entering the pipes can cause backups that result in sanitary sewer overflows. Urban underground infrastructure monitoring is important for controlling the flow of extraneous water into the pipelines. By combining the wireless underground communications and sensor solutions, the urban underground IoT applications such as real time wastewater and storm water overflow monitoring can be developed. In this paper, the path loss analysis of wireless underground communications in urban underground IoT for wastewater monitoring has been presented. It has been shown that the communication range of up to 4 kilometers can be achieved from an underground …
2019 Student Steel Bridge Team, Kourtney Arena, Andrew Biglin, Brett Palmer, Nathaniel Maute, Kenneth Reiser, Jacob Dicks, Paul Kowaleski
2019 Student Steel Bridge Team, Kourtney Arena, Andrew Biglin, Brett Palmer, Nathaniel Maute, Kenneth Reiser, Jacob Dicks, Paul Kowaleski
STEM Student Research Symposium Posters
Every year AISC runs a regional and national steel bridge competition. The competition offers a chance for civil engineering students to gain valuable experience designing a bridge. In addition to this, mechanical engineering students are provided the opportunity to practice machining steel parts. For the competition, teams from participating schools are given a scenario with certain constraints to design a bridge for. At the competition, the bridges are ranked based on weight, structural efficiency, construction economy, assembly speed, deflection, aesthetics, and overall performance.
The program Risa 3D was used in order to design and perform analysis on the bridge. Using …
Unl-Cc Outdoor Education Center Master Plan, Marie Wagner
Unl-Cc Outdoor Education Center Master Plan, Marie Wagner
Honors Program: Senior Projects (Public)
The following report contains the work done by the group Griswold Engineering in completion of the Senior Design requirements for Civil Engineering and the Honors Requirements of the Project Manager. As the project manager, my job was to organize the project as a whole and to work alongside the Structural Engineer on the project. One of the main problems to overcome was the division of labor amongst the group. The project was originally conceived as a group project with one project manager and five other students to serve as the project engineers in each subdiscipline. Since this group only had …
Development Of Post-To-Deck Connections For Use In A Mash Tl-4 Steel-Tube Bridge Rail, Pascual Mauricio
Development Of Post-To-Deck Connections For Use In A Mash Tl-4 Steel-Tube Bridge Rail, Pascual Mauricio
Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research
A new post-to-deck connection was designed for mounting an upcoming Manual for Assessing Safety Hardware (MASH) Test Level 4 steel-tube bridge rail to the side of the bridge deck to limit impact load transferred to the deck and to minimize the propensity for deck damage during impacts. With preference for the bridge rail system to be compatible for use on all deck configurations, the Illinois and Ohio Departments of Transportation desired the new system to attach to bridge decks comprised of concrete slabs or precasted prestressed, concrete box-beam girders.
A new post-to-deck connection for a new MASH 2016 TL-4 steel-tube …
An Agent-Based Evacuation Model To Improve Safety In The Cascadia Subduction Zone, Haizhong Wang
An Agent-Based Evacuation Model To Improve Safety In The Cascadia Subduction Zone, Haizhong Wang
PSU Transportation Seminars
This seminar will present ongoing research into how integrated social, natural, and engineered systems can improve life safety under threat of multi-hazards. The targeted scenario is a magnitude 9.0 earthquake and tsunami from the Cascadia Subduction Zone, threatening communities along 1,000 miles of the US Pacific Northwest coastline.
Since the mid-1980’s scientific evidence has underscored the possibility of such an extreme event, and it has taken at least another decade or more before public attitudes and policy have begun to adapt to this new hazard. Life safety is a pressing issue for the near-field CSZ tsunami hazard for several reasons. …
Spectral Analysis Of Train-Rail-Bridge Coupling System Considering Frequency-Dependent Stiffness Of Rail Fastening Systems, Linya Liu, Jialiang Qin, Quanmin Liu, Jong-Dar Yau, Rui Song
Spectral Analysis Of Train-Rail-Bridge Coupling System Considering Frequency-Dependent Stiffness Of Rail Fastening Systems, Linya Liu, Jialiang Qin, Quanmin Liu, Jong-Dar Yau, Rui Song
Journal of Marine Science and Technology–Taiwan
A rubber rail-pad is typically inserted between the rail and the sleeper to attenuate wheel/rail vibrations for conventional train-rail-bridge (TRB) system. For mathematical modeling, a rail-fastener with rubber pad is simplified as a spring-dashpot unit, whose spring stiffness is related to the exciting frequency of external loads. To exhibit such characteristics of rail-pads on TRB dynamics, based on dynamic flexibility method, two computational models of constant/frequency-dependent stiffness (FDS) are considered for comparison. Numerical studies reveal that the FDS model provides a strengthening benefit for the wheelrail vibration, from which the shifted dominant frequencies in spectral response are observed.
Influence Of Fly Ash Fineness And High Replacement Ratios On Concrete Properties, Shihwen Hsu, Maochieh Chi, Ran Huang
Influence Of Fly Ash Fineness And High Replacement Ratios On Concrete Properties, Shihwen Hsu, Maochieh Chi, Ran Huang
Journal of Marine Science and Technology–Taiwan
The influence of fly ash (FA) fineness and a high cement replacement ratio on concrete properties was investigated. Class F FA with an original fineness of 3,150 cm2 /g (3F) and a high fineness of 5,690 cm2 /g (5F) was used; high cement replacement ratios of 30%, 40%, 50%, and 60% by FA with different levels of fineness (two groups: 3F30, 3F40, 3F50, 3F60, and 5F30, 5F40, 5F50, 5F60 by weight of cement) were selected to produce the blended cement concrete. Tests regarding the heat of hydration, compressive strength, water absorption, rapid chloride penetration, and Mercury intrusion porosimetry were performed. …
Strength Of Steel-To-Steel Screw Connections -- Update To Provisions, Thomas Stevens, Thomas Sputo, Jennifer Bridge
Strength Of Steel-To-Steel Screw Connections -- Update To Provisions, Thomas Stevens, Thomas Sputo, Jennifer Bridge
American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)
The objective of this project is to review the existing provisions of the AISI S100-16 North American Specification for Cold-Formed Steel Structural Members, for screw connections loaded in shear and tension (but not combined actions). A recent study by the Steel Deck Institute (Sputo 2017) revealed possible unconservative results for screw pull-over, particularly in thinner sheets and/or lower ductility.
This study performed a comprehensive analysis of available steel-to-steel screw connection strength test data, totaling 702 shear tests, 143 pull-over tests, and 335 pull-out tests. The tested strength of these connections was compared to the predicted strength from the existing …
Behavior Of Geothermal Energy Piles Embedded In Rock, Ehab Sabi
Behavior Of Geothermal Energy Piles Embedded In Rock, Ehab Sabi
Civil and Environmental Engineering Theses and Dissertations
Geothermal energy piles are categorized as closed systems. Energy piles are a relatively new technology which couples the structural role of traditional pile foundations to that of heat exchangers to fulfill the required energy demand of buildings and infrastructures. These foundations are equipped with pipes embedded in the concrete forming the pile. While connected to a heat pump, the fluid circulating inside these pipes provides the exchange of heat with the ground for heating and cooling purposes. As the undisturbed temperature at the shallower depths of the ground stays comparatively constant the whole year, being warmer than the surrounding temperature …
Civil Engineering Design Of Cornhusker Council's Outdoor Education Center, Kelly Weiler
Civil Engineering Design Of Cornhusker Council's Outdoor Education Center, Kelly Weiler
Honors Program: Senior Projects (Public)
A team of geotechnical, structural, hydraulic, environmental, and transportation experts collaborated to provide engineering solutions to the Cornhusker Council in an effort to solve the current problems facing their Outdoor Education Center. This results of this project provided the structural design of three bridges on the property, transportation plans for two parking lots and roadway design, geotechnical recommendations for soil testing and erosion prevention, and an environmental and hydraulic analysis of the property. A major challenge in the design of this project is the consideration of the dangers and regulations that accompany the floodway and floodplain regions on site. Various …
Fiber-Reinforced Polymer Bridge Girders For Extremely Aggressive Environments, Abdellah Emad Azeez
Fiber-Reinforced Polymer Bridge Girders For Extremely Aggressive Environments, Abdellah Emad Azeez
Doctoral Dissertations and Master's Theses
In 2012, the federal government estimated that $17.5 billion was spent on inspection, rehabilitation, maintenance, and replacement of the nation’s bridges. While the average lifespan of steel and reinforced concrete bridges is 50 years, certain bridges subjected to extremely aggressive marine environments may not reach this desired target. This research paper investigates using fiber-reinforced polymer (FRP) materials as primary bridge girders in medium span bridges (30 ft. to 75 ft.). The goal of this research is to identify the most efficient and cost-effective alternative for these corrosion-resistant materials and potentially extend the lifespan of these bridges up to 75 years. …
Wavelet Transform On Digital Rainbow Hologram Based On Spectral Compression For Quality Enhancement In 3d Display Media, Ucuk Darusalam, Panca Dewi Pamungkasari
Wavelet Transform On Digital Rainbow Hologram Based On Spectral Compression For Quality Enhancement In 3d Display Media, Ucuk Darusalam, Panca Dewi Pamungkasari
Makara Journal of Technology
A digital rainbow hologram (DRH) is a potential next-generation three-dimensional display media for the development of modern and smart electronics devices. It is one of the methods that can support the characteristic whereby a realistic display media occupies the space that the real object would have occupied. Since a rainbow hologram records a large amount of spatial or temporal frequency component from the object that represents the rainbow spectrum, a large amount of information needs to be decoded digitally. In this paper, to reconstruct a DRH, we propose a novel method based on the modulation of red, green, and blue …
The Timber Buckling Restrained Brace Frame, Jessica Resta
The Timber Buckling Restrained Brace Frame, Jessica Resta
Architectural Engineering
With the increasing awareness on the topic of earthquake resistance, efficient, cost-effective, and environmentally friendly solutions in the structural field are on the rise. The purpose of this report is to investigate the Timber Buckling Restrained Brace (TBRB), a new lateral-resisting element made of steel and lumber, applicable in residential and small commercial units. In addition to the TBRBs’ materials being readily available, the braces are easy to manufacture, reducing overall costs of production and transportation. The brace, made partly of wood, has also a low environmental impact when compared to other lateral force resisting elements like concrete shearwalls or …
Molecularly Conductive Behavior Of Blended Polymer Electrolyte-Based Cmc/Pva, Noor Saadiah Mohd Ali, Dishen Zhang, Yuki Nagao, Ahmad Salihin Samsudin
Molecularly Conductive Behavior Of Blended Polymer Electrolyte-Based Cmc/Pva, Noor Saadiah Mohd Ali, Dishen Zhang, Yuki Nagao, Ahmad Salihin Samsudin
Makara Journal of Technology
This study investigated the electrical conduction and structural behavior of blended polymer electrolyte (BPE)-based carboxymethyl cellulose (CMC) and polyvinyl alcohol (PVA) in the development of solid-state electrochemical devices. Based on impedance spectroscopy and correlating Fourier transform infrared (FTIR) with thermogravimetric analysis, a framework was proposed to explain the structural enhancement of the BPE system. As revealed by FTIR, the optimum conductivity of CMC/PVA BPEs was 9.21 × 10−6 Scm−1 for 80:20 composition attributed to the intermolecular attraction between the polymers. Thermal stability of the CMC/PVA was influenced by the formation of a hydrogen bond between the hydroxyl (-OH), carboxylate (-COO-), …
Multistage Sonication Effect On The Composition And Properties Of Degraded Chitosan Product, Nurul Laili Arifin, Emma Savitri, Anjar Indah, Fesa Putra, Sumarno Sumarno
Multistage Sonication Effect On The Composition And Properties Of Degraded Chitosan Product, Nurul Laili Arifin, Emma Savitri, Anjar Indah, Fesa Putra, Sumarno Sumarno
Makara Journal of Technology
The sonication method randomly breaks polymer chains to produce a varied distribution of products. A scheme with multi-stage sonication steps is proposed to identify oligomers and low molecular weight chitosan based on changes to the degrad-ed product. For each sonication level, 1% (w/v) chitosan in 1% (v/v) aqueous acetic acid was sonicated for 120 min at 60 °C. The products of the sonication treatment were deprotonized by adding an alkali solution, freeze dried and insoluble product re-sonicated until a low molecular weight was produced. Low molecular weight chitosan/insoluble products were character-ized with Fourier-transform infrared spectra (FT-IR) and X-ray diffraction (XRD) …