Lateral Torsional Buckling Resistance Of Continuous Steel Stringers In Existing Bridges,
2021
Louisiana Tech University
Lateral Torsional Buckling Resistance Of Continuous Steel Stringers In Existing Bridges, Dinesha Malky Kuruppuarachchi Kuruppuarachchi Appuhamilage Don
Master's Theses
Some of the Louisiana’s bridges built in the 1950s and 1960s used two-girder or truss systems, in which floorbeams are carried by main members and the continuous (spliced) stringers are supported by the floorbeams. The main members are either two edge (fascia) girders or trusses. When the flexural capacity of continuous stringers is calculated, the moment gradient factor (Cb) is not accurately calculated considering the lateral torsional buckling (LTB) at the negative moment section. In particular, the bracing effect of the non-composite concrete deck is not accounted for, and as a result, the current practice has underestimated the LTB strength …
Environmental Geotechnics: Challenges And Opportunities In The Post-Covid-19 World,
2021
Boise State University
Environmental Geotechnics: Challenges And Opportunities In The Post-Covid-19 World, Arvin Farid
Civil Engineering Faculty Publications and Presentations
The outbreak of the coronavirus disease 2019 (Covid-19) pandemic not only has created a health crisis across the world but is also expected to impact negatively the global economy and societies at a scale that is maybe larger than that of the 2008 financial crisis. Simultaneously, it has inevitably exerted many negative consequences on the geoenvironment on which human beings depend. The current paper articulates the role of environmental geotechnics in elucidating and mitigating the effects of the current pandemic. It is the belief of all authors that the Covid-19 pandemic presents not only significant challenges but also opportunities for …
Lateral Torsional Buckling Resistance Of Continuous Steel Stringers In Existing Bridges,
2021
Louisiana Tech University
Lateral Torsional Buckling Resistance Of Continuous Steel Stringers In Existing Bridges, Dinesha Malky Kuruppuarachchi Kuruppuarachchi Appuhamilage Don
Doctoral Dissertations
Some of the Louisiana’s bridges built in the 1950s and 1960s used two-girder or truss systems, in which floorbeams are carried by main members and the continuous (spliced) stringers are supported by the floorbeams. The main members are either two edge (fascia) girders or trusses. When the flexural capacity of continuous stringers is calculated, the moment gradient factor (Cb) is not accurately calculated considering the lateral torsional buckling (LTB) at the negative moment section. In particular, the bracing effect of the non-composite concrete deck is not accounted for, and as a result, the current practice has underestimated the LTB strength …
Shallow 3d Shear Wave Velocity Model And Revised Site Period Prediction Map For The Mexico City Basin,
2021
University of Arkansas, Fayetteville
Shallow 3d Shear Wave Velocity Model And Revised Site Period Prediction Map For The Mexico City Basin, Rendon Martin Rieth
Graduate Theses and Dissertations
The goal of this study was to revise the existing site period prediction map and to develop a shallow 3D shear wave velocity model of the Mexico City Basin. To accomplish this goal, an extensive literature review was performed to compile as much pertinent shear wave velocity and site period data for the region. In total, 75 sites were used to revise the site period prediction map and 40 sites were used to develop the shear wave velocity model. The 2004 Complementary Technical Standards of Mexico site period prediction map was adjusted with new site period measurements across the basin …
Comparison Of The Resistance Of Belitic Calcium Sulfoaluminate Cement And Portland Cement To Sulfate Attack And Sulfuric Acid,
2021
University of Arkansas, Fayetteville
Comparison Of The Resistance Of Belitic Calcium Sulfoaluminate Cement And Portland Cement To Sulfate Attack And Sulfuric Acid, Rilye Dillard
Graduate Theses and Dissertations
Microbially induced corrosion (MIC) is a fairly common concrete deterioration mechanism with many negative effects. MIC is a complex chemical and biological process that occurs in sewage systems and is nearly impossible to replicate in a laboratory setting. For this study, sulfate and sulfuric acid attack on concrete were studied to mimic two stages of the MIC process. The ASTM C1012, Standard Test Method for Length Change of Hydraulic-Cement Mortars Exposed to a Sulfate Solution and a modified ASTM C1012 accelerated method were used to compare the sulfate resistance of belitic calcium sulfoaluminate (BCSA) cement, portland cement (PC), and PC-fly …
Experimental Design And Preliminary Testing For Skewed Special Moment Frame Prequalification,
2021
University of Arkansas, Fayetteville
Experimental Design And Preliminary Testing For Skewed Special Moment Frame Prequalification, Sara Alimirzaei
Graduate Theses and Dissertations
Special moment frames having specially detailed connections are common in high seismic regions, providing architectural flexibility for passageways and views without brace obstructions. In situations where the building framing layout requires deviation from typical rectangular framing, skew in the moment frame connections may be required. Currently, the AISC prequalified connections only include testing of orthogonal moment frame connections and it is unclear whether the existing design methods can accommodate skew at the beam-to- column connections. To investigate the effect of out-of-plane skew on the performance of reduced beam section special moment frame connections, an experimental test is designed and a …
Development Of An Ultraviolet Absorbance Assay To Estimate Air Entrainer Dosing For Concrete Containing Fly Ash,
2021
University of Arkansas, Fayetteville
Development Of An Ultraviolet Absorbance Assay To Estimate Air Entrainer Dosing For Concrete Containing Fly Ash, James Spencer
Graduate Theses and Dissertations
Fly ash is a coal combustion byproduct that can be used as a supplementary cementitious material (SCM) in concrete, offering benefits such as increased workability, durability, and strength. Fly ash can be used as a partial replacement to cement, reducing concrete productions costs and decreasing disposal in landfills. However, variability of fly ash properties (e.g., carbon content, adsorption site density) confounds estimates of the air entraining admixture (AEA) dose needed to achieve a specified air content in concrete. Air entrainment is needed to improve freeze-thaw resistance and limit concrete cracking. The foam index (FI) test is currently used to estimate …
Vistas: Vocational Immersive Storytelling Training And Support Framework For Augmenting Work Performance,
2021
University of Texas at Arlington
Vistas: Vocational Immersive Storytelling Training And Support Framework For Augmenting Work Performance, Sanika Doolani
Civil Engineering Theses - Archive
Training and assessment of novice workers are the most vital part of any vocational industry. Innovations in science and technology have led to the creation of new industries and occupations, enhanced productivity and quality of work-life, and increased the potential for more people to participate in the workforce. However, these come at the risk and disadvantage of an increased cost of training and lack of proper training in industries, such as manufacturing. Recently, the use of Extended Reality (XR) systems has been on the rise to tackle various domains such as training, education, safety, etc. With the recent advances in …
Numerical Simulation Of Anchor Group Effects On Concrete Breakout Strength Within Steel Fiber Reinforced Concrete,
2021
University of Texas at Arlington
Numerical Simulation Of Anchor Group Effects On Concrete Breakout Strength Within Steel Fiber Reinforced Concrete, Harjasdeep Singh Chauhan
Civil Engineering Theses - Archive
This study aims to investigate numerically, the effect of anchor groups on concrete breakout strength using nonlinear finite element analysis. Steel headed studs were cast in place within concrete of different amounts of steel fibers. Different proportions of steel fibers (0%, 0.5%, 1%, 1.5%) were utilized within steel fiber reinforced concrete (SFRC) for the numerical simulation. The physical properties of SFRC were modelled with respect to its composite compressive and tensile strength obtained from the experiments. The analysis was conducted on the concrete breakout strength of anchor bolts within SFRC. A good agreement was achieved between the numerical and the …
Effect Of Modified Moisture Barrier In Mitigating Pavement Distresses Due To Expansive Subgrade,
2021
University of Texas at Arlington
Effect Of Modified Moisture Barrier In Mitigating Pavement Distresses Due To Expansive Subgrade, Pratibha Pandey
Civil Engineering Dissertations - Archive
Surficial distresses in roadways of Texas are very common due to presence of high plastic clayey soil in the subgrade. Increased sensitivity of high plastic clay towards seasonal moisture change results in repeated swelling and shrinkage, and ultimately the development of pavement cracks. Annual expenses of such distresses impose huge financial liability to maintenance authorities. Studies have indicated rainwater intrusion into underlying expansive subgrade soil coupled with inadequate drainage as the main cause of pavement damage in semi-arid regions. The inability of drainage layer to laterally drain the excess moisture may lead to moisture accumulation within the base layer which …
Evaluation And Retrofitting Of Prestressed Concrete Girder Bridge With Excessive Vibration,
2021
University of Texas at Arlington
Evaluation And Retrofitting Of Prestressed Concrete Girder Bridge With Excessive Vibration, Ikram Hasan Efaz
Civil Engineering Dissertations - Archive
Vibration of a highway bridges is a serviceability issue according to American Association of State Highway and Transportation Officials (AASHTO). Though vibration is one of the primary reasons of bridge deck cracking, AASHTO only has a deflection limit to counterpart vibration which is not adequate according to many researchers. For instance, SH-75 SB Bridge over Wilson Creek in McKinney, Texas was observed to have excessive vibration and cracking on the concrete deck. To evaluate the condition of the bridge, Ground Penetrating Radar (GPR) and Impact Echo (IE) were used on the deck as Non-Destructive Evaluation (NDE) methods. A diagnostic load …
Effect Of Sludge Content On Different Types Of Food Waste Degradation In Anaerobic Digester,
2021
University of Texas at Arlington
Effect Of Sludge Content On Different Types Of Food Waste Degradation In Anaerobic Digester, Mumtahina Binte Latif
Civil Engineering Theses - Archive
Food waste (FW) is the second-largest component in landfills which impacts environments adversely by generating excessive leachate and greenhouse gas. Generally, conventional anaerobic digester and composting can be used for FW disposal. However, the former is highly expensive while the latter is energy inefficient. In contrast, household or community level underground anaerobic digester offers a cost-efficient solution as well as retrieves valuable energy from FW. The addition of nutrients such as sludge to organic waste especially FW accelerates the production of energy by limiting volatile fatty acid (VFA) accumulation. The objective of the current study is to find out the …
An Analytical, Numerical, And Experimental Study Of Automated Damage Assessment For Concrete Structures,
2021
University of Texas at Arlington
An Analytical, Numerical, And Experimental Study Of Automated Damage Assessment For Concrete Structures, Sanggoo Kang
Civil Engineering Dissertations - Archive
This dissertation presents the automated damage assessment studies for concrete structure. Three major studies are performed to: 1) understand the theoretical wave scattering model to evaluate the internal vertical crack, 2) to validate the theoretical wave scattering model through FE simulations with experimental measurements, and 3) to advance practical automated crack evaluation (ACE) system for vertical crack and delamination detection. Firstly, singular integral solutions are studied to investigate scattering of Rayleigh waves by subsurface cracks. Defining a wave scattering model by objects, such as cracks, still can be quite a challenge. The model’s analytical solution uses five different numerical integration …
Understanding Process Controls On Flow Duration Curves Through A Novel Framework,
2021
University of Central Florida
Understanding Process Controls On Flow Duration Curves Through A Novel Framework, Saba Ghotbi
Electronic Theses and Dissertations, 2020-2023
Flow duration curve (FDC) is a hydrologically representation of the statistical distribution of daily streamflows. For a long time, hydrologists have sought deeper understanding of the process controls on the shape of FDC, which has been a challenge due to contrasting processes controlling the fast flow and slow flow components of streamflow and their interactions. This dissertation addresses the challenge by outlining a novel framework to explore the physical controls on FDC. The framework involves separating streamflow into fast flow and slow flow and studying their duration curves separately then combining them statistically to obtain FDC. Initially, the potential of …
Characterization Of Msw And Plastic Waste Volume Estimation During Covid-19 Pandemic,
2021
University of Texas at Arlington
Characterization Of Msw And Plastic Waste Volume Estimation During Covid-19 Pandemic, Sehneela Sara Aurpa
Civil Engineering Theses - Archive
COVID-19 has appeared and shook all aspects of our life. Starting from panic buying prior lockdown to the availability of vaccine, the whole world has gone through a pandemic situation which bounded people to live a life that never seemed normal before. Lockdown and risk of spreading disease forced people to stay at home and generate more waste, especially plastic waste. The effect on municipal solid waste characteristics due to this shift in the way of living is assessed in this study. In this study, municipal solid waste was collected from the working face of Irving Hunter Ferrell landfill. Waste …
Feasibility Assessment Of Production Of Liquid Organic Fertilizer (Lof) From Food Waste For Sustainable Waste Management,
2021
University of Texas at Arlington
Feasibility Assessment Of Production Of Liquid Organic Fertilizer (Lof) From Food Waste For Sustainable Waste Management, Shadman Sakib
Civil Engineering Theses - Archive
The increasing volume of food waste is responsible for the generation of potent greenhouse gases and is resulting in the wastage of valuable resources. In all regions of the world, the percentage of food waste in municipal solid waste is greater. Due to the lack of waste segregation at collection points and modern waste disposal methods in developing countries, organic waste is piling up in the dumpsites and landfills. Besides due to poor harvest and post-harvest procedures and inefficient supply chain, almost 55% of the cultivated crops do not even reach the consumers and get wasted. On the other hand, …
A Comprehensive Framework To Mitigate Surficial Slope Failures,
2021
University of Texas at Arlington
A Comprehensive Framework To Mitigate Surficial Slope Failures, Burak Boluk
Civil Engineering Dissertations - Archive
Each year, numerous highway and dam slopes that are built with high plasticity clays experience shallow slope failures. Besides the high maintenance and repair costs, these failures negatively impact the public life by interrupting the traffic flow and causing serious safety hazards. The development of desiccation cracks due to weathering cycles deteriorates hydro-mechanical properties of soil, increases water infiltration, and ultimately results in surficial slope failure. Several slope rehabilitation methods have been developed to stabilize clayey soil slope sections affected by surficial failures. Lime stabilization is an effective treatment method that generally reduces the swell-shrink potential of expansive soil and …
Pavement Temperature Response To Cold Fronts: A Model Column Study In A Freezer Box,
2021
University of Texas at Arlington
Pavement Temperature Response To Cold Fronts: A Model Column Study In A Freezer Box, Taryn Dilorenzo
Civil Engineering Theses - Archive
The correlation of meteorological data and pavement conditions is crucial for winter pavement maintenance, this is the main reason that it is so important to understand in what ways pavement responds to cold fronts as well as when the formation of ice on a pavement surface can be expected. The pavement surface and its underlying subsurface layers combine to create a system with the behavior of the surface being influenced by both the air temperature above it, as well as the temperature and thermodynamic processes occurring in the sublayers below it. Both the pavement surface as well as the sublayers …
Flexural Strengthening Of Two-Way Slabs Using Cfrp External Laminates,
2021
University of Texas at Arlington
Flexural Strengthening Of Two-Way Slabs Using Cfrp External Laminates, Shams Abbas Naqvi
Civil Engineering Theses - Archive
Deterioration of reinforced concrete structures with time is a common phenomenon, which often leads to reduction in the load carrying capacity. To meet the coding requirements, strengthening of these structures is of utmost importance. Composite materials, such as Carbon Fiber Reinforced Polymers (CFRP), have shown effective results in external strengthening of these structures. However, premature delamination of CFRPs can decrease their efficiency. Recently, pre-saturated CFRP (PS-CFRP), a new type of CFRP pre-impregnated with epoxy resin, was introduced. Previous research has shown that PS-CFRP has shown improved results as compared to regular CFRP (R-CFRP) for strengthening beams and columns. However, no …
Investigating Topologic And Geometric Properties Of Synthetic And Natural River Networks Under Changing Climate,
2021
University of Central Florida
Investigating Topologic And Geometric Properties Of Synthetic And Natural River Networks Under Changing Climate, Shiblu Sarker
Electronic Theses and Dissertations, 2020-2023
River networks are important landscape features that collect and transport water, sediment and nutrients from regions of higher elevation to lower elevations. These networks have been studied for several decades from a range of geomorphological and hydrological perspectives. Investigating the geometric and topological properties of river networks is important for developing predictive models describing the network dynamics under changing climate as well as for quantifying the physical processes operating upon them. Although these networks have been characterized for a wide range of geomorphic properties, topological properties, and in particular, spectral properties of river networks received limited attention. In this dissertation, …
