Civil and Environmental Engineering Commons^™

Numerical And Analytical Methods To Predict Behavior Of Reinforced Ductile Concrete Composites, Mandeep Pokhrel

Dissertations

Structural components constructed with ductile concrete composites, such as high-performance fiber-reinforced cementitious composites (HPFRCC), are known to perform exceptionally well under extreme mechanical and environmental loading conditions compared to traditional concrete. HPFRCC flexural components exhibit enhanced performance in terms of displacement ductility, energy dissipation capacity, and damage tolerance capacity. However, recent research suggests that the flexural behavior of reinforced HPFRCCs in terms of crack progression, reinforcement plasticity, and failure mechanism is significantly different than conventional reinforced concrete. Specifically, the failure mode of flexural members is found to be predominantly through the fracture of longitudinal reinforcement rather than compression crushing of …

The Impact Of Conversion On The Durability Of Calcium Aluminate Cement Concrete Systems, Marwa Mohsen Korayem

Dissertations

The deterioration of infrastructure in North America has resulted in a significant need for concrete repair materials that can be used to maintain service life of these structures. Hydraulic cement based rapid repair materials can be used to repair pavement and bridge deterioration with minimal impact on economic activities such as freight handling or public transportation. While there are many options for use in repair situations, calcium aluminate cements have become more popular recently, particularly in situations where repairs must be completed rapidly.

Calcium aluminate cement (CAC) is a cement characterized by its rapid strength gain, even at low temperatures …

Enhanced Removal Of Perfluorooctanoic Acid (Pfoa) Via Microwave-Fenton-Reactive Membrane Filtration, Fangzhou Liu

Theses

Perfluorooctanoic Acid (PFOA), one of the common per- and poly fluorinated alkylated substances (PFASs), is increasingly detected in the environment due to the diverse industrial applications and high resistance to degradation processes. This study evaluated degradation of PFOA in microwave-assistant catalytic membrane filtration, a process that integrates microwave catalytic reactions into a ceramic membrane filtration. First, water permeation of the pristine and catalyst-coated membranes were examined under the influence of microwave irradiation to analyse the impacts of the coating layer and water temperature increase on permeate flux, which were well interpreted by three models. Then, the PFOA removal was first …

Recovery Of Valuable Metals From Spent Lithium-Ion Batteries Using Organic Acids: Assessment Of Technoeconomic Feasibility, Leqi Lin

Theses

Lithium ion batteries (LIBs) are used in diverse electronic products with anticipated over 500 thousand tonnes of the waste LIBs globally in 2020. To protect the environment and also recover valuable materials such as lithium (Li) and cobalt (Co), our research employed a hydrometallurgy method and demonstrated that exposure of spent LIBs to Organic Aqua Regia (OAR) could leach Li and Co without the pre-separation of cathode from Al foil using organic solvents such as Dimethylformamide (DMF) and N-Methyl-2-pyrrolidone (NMP). The leaching efficiency of 99% and 94% for Li and Co were obtained with a leaching rate of 0.021, 0.167 …

Backing Up Into Advocacy: The Case Of Smartphone Driver Distraction, Robert Rosenberger

The Journal of Sociotechnical Critique

For the last decade, I’ve been studying the topic of the driving impairment of smartphones. While this began as an exclusively academic project, it has increasingly compelled public engagement. One example of this came in an opinion piece I wrote in 2018 in response to a new traffic law. I take the opportunity here to fill out the academic backstory of this particular op-ed, reflect on how this larger project has evolved to include an unanticipated public-facing edge, and abstract some lessons about public writing.

Fast Summarizing Algorithm For Polygonal Statistics Over A Regular Grid, Scott Haag, David G. Tarboton, Martyn Smith, Ali Shokoufandeh

Publications

We describe a data structure and associated algorithm called Fast Zonal Statistics (FZS) for the retrieval of the summary characteristics of an arbitrary polygon derived from a regular grid. The FZS algorithm can return numerical (e.g., mean, sum, and count) attributes for a polygonal object over a regular grid (e.g., raster data model). The computational complexity of the FZS algorithm is constant in relation to the length of the polygon perimeter. This contrasts with existing approaches which scale in relation to the polygon area, therefore we expect and measure geometric decreases in execution time using the proposed approach for simple …

Reliability Analysis Of Concrete Gravity Dams Under Earthquake Loads, Anu Abraham

LSU Master's Theses

Dams are infrastructure assets of extreme importance; the failure of which can have catastrophic consequences on adjacent communities. Therefore, it is prudent for authorities to evaluate the safety of existing dams in seismically active regions. This thesis focuses on carrying out a reliability analysis of concrete gravity dams under earthquake loads using an enhanced finite element model. For many years, reliability studies on concrete gravity dams were performed using a finite element model that considered a massless foundation and assumed that water is incompressible. Moreover, the design ground motion was applied without any modification either at the bottom fixed boundary …

Study Of The Effect Of Heating - Cooling Cycles On The Clay - Concrete Pile Interface Characteristics, Abedalqader Ahmad Idries

LSU Master's Theses

This study aimed at investigating the effect of heating-cooling cycles on the interface strength parameters of clay soil-concrete for potential applications to improve the side capacity of piles driven in clayey soil by the heating process, and also to assess the behavior of geothermal piles regarding interface shear strength parameters. A modified large-size direct shear test device with the dimensions 12” x 12” x 8”, was used in this study. A concrete block (12” x 12” x 4”) of similar texture and smoothness to the concrete piles was used to simulate the pile interface. The tested clays are low plasticity …

Identification Of Top-Down, Bottom-Up, And Cement-Treated Reflective Cracks Using Convolutional Neural Network And Artificial Neural Network, Nirmal Dhakal

LSU Doctoral Dissertations

The objective of this study was to formulate a Convolutional Neural Networks (CNN) model and to develop a decision-making tool using Artificial Neural Networks (ANN) to identify top-down, bottom-up, and cement treated (CT) reflective cracking in in-service flexible pavements. The CNN’s architecture consisted of five convolutional layers with three max-pooling layers and three fully connected layers. Input variables for the ANN model were pavement age, asphalt concrete (AC) thickness, annual average daily traffic (AADT), type of base, crack orientation, and crack location. The ANN network architecture consisted of an input layer of six neurons, a hidden layer of ten neurons, …

Enhancing Facility Management For Existing Facilities With Building Information Modeling, Ryan Loeh

Theses and Dissertations

Building information modeling (BIM) refers to the process of creating a comprehensive three-dimensional (3D) model that allows for a seamless transition from design and construction to operation & maintenance during a building's lifecycle. While a majority of past research for building information modelling was focused on design and construction, research has shifted to operation, maintenance and renovation. This study investigates the feasibility of integrating BIM (Autodesk Revit) and facility management (BUILDER SMS). BUILDER SMS is currently used at the sponsor's facilities to encourage proactive maintenance and provide updated condition assessments. While both datasets have their own benefits, this study investigates …

Implications Of Soil And Canopy Temperature Uncertainty In The Estimation Of Surface Energy Fluxes Using Tseb2t And High-Resolution Imagery In Commercial Vineyards, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Héctor Nieto, Mac Mckee, Lawrence Hipps, Joseph Alfieri, John H. Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Luis Sanchez, Nick Dokoozlian

Civil and Environmental Engineering Faculty Publications

Estimation of surface energy fluxes using thermal remote sensing–based energy balance models (e.g., TSEB2T) involves the use of local micrometeorological input data of air temperature, wind speed, and incoming solar radiation, as well as vegetation cover and accurate land surface temperature (LST). The physically based Two-source Energy Balance with a Dual Temperature (TSEB2T) model separates soil and canopy temperature (Ts and Tc) to estimate surface energy fluxes including Rn, H, LE, and G. The estimation of Ts and Tc components for the TSEB2T model relies on the linear relationship between the composite land surface temperature and a vegetation index, namely …

To What Extent Does The Eddy Covariance Footprint Cutoff Influence The Estimation Of Surface Energy Fluxes Using Two Source Energy Balance Model And High-Resolution Imagery In Commercial Vineyards?, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Héctor Nieto, Mac Mckee, Lawrence Hipps, Joseph Alfieri, John H. Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Louis Sanchez, Nick Dokoozlian

Civil and Environmental Engineering Faculty Publications

Validation of surface energy fluxes from remote sensing sources is performed using instantaneous field measurements obtained from eddy covariance (EC) instrumentation. An eddy covariance measurement is characterized by a footprint function / weighted area function that describes the mathematical relationship between the spatial distribution of surface flux sources and their corresponding magnitude. The orientation and size of each flux footprint / source area depends on the micro-meteorological conditions at the site as measured by the EC towers, including turbulence fluxes, friction velocity (u_star), and wind speed, all of which influence the dimensions and orientation of the footprint. The …

Understanding Air Pollutants And Meteorology Interactions Using Chemical Transport Models, Pengfei Wang

LSU Doctoral Dissertations

Air pollution is a worldwide threat to human health and ecosystems, especially in developing countries. After being emitted to the atmosphere, air pollutant concentrations are determined by chemical and physical processes including transport, transformation, and deposition, which are largely affected by meteorological variations. In turn, pollutants such as fine particulate matter (PM_2.5) affect meteorology by impacting solar radiation and cloud condensation processes. Thus, it is important and necessary to understand the interactions between air pollutants and meteorology for better designing effective air pollution control strategies and forecasting weather. In this study, two chemical transport models (CTMs) are applied …

Modeling Of Distributary Channels Formed By A Large Sediment Diversion In Broken Marshland, Dylan Blaskey

LSU New Orleans Theses and Dissertations

A 2-D DELFT3D model was developed to address the morphological response of Barataria Bay, the sediment deposition rate in the receiving basin, and the impact on the existing distributary channels within the broken marsh system due to the proposed Mid-Barataria Sediment Diversion. The model had a mesh size sufficient to accurately represent the development of the distributary channels, localized flooding, erosion, and salinity in the basin. The model predicts that the receiving basin will experience extensive erosion during the first year the diversion is open creating three major distributary pathways which flood much of the basin in freshwater. Most locations …

Response Of Large Diameter Offshore Wind Turbine Monopile Foundations To Extreme Event Loading Expected At U.S. Atlantic Coast Wind Energy Areas, Laura Hulliger

LSU New Orleans Theses and Dissertations

Extra-tropical (ETC) and tropical cyclones (TC) pose potential risks to offshore wind farms along the U.S. Atlantic coast, where the offshore wind energy industry is gaining momentum. This research aims to evaluate the stability of large diameter offshore wind turbine monopile foundations under these extreme conditions using the governing industry practice in IEC 61400-3-1. To quantify the risk at U.S. Atlantic coast wind energy areas (WEAs), the ETC and TC impact frequency and intensity are identified using the NHC Historical Hurricane Tracks Archive. Numerical simulations in Plaxis 3D are performed on foundations ranging from 8 to 12 meters in diameter …

Suitability Of Fusing Vehicle Probe Data And Vessel Data To Contextualize The Multimodal Interaction Impacts On Corridor Mobility – A New Orleans Case Study, Kirk Zeringue

LSU New Orleans Theses and Dissertations

Using New Orleans as a case study, this thesis explores the conflation of vehicle probe data with various vessel datasets to characterize the interactions between container vessels and motor vehicles as it relates to interstate congestion in a port city. The case study investigates the impact of container vessel presence/size, fluctuations in container volumes, and container on barge services on roadway congestion. The exploration relies on comparing different conditions using cumulative distribution functions and the Innovative Trend Analysis. The results showed that fusing vehicle and vessel data is achievable and appropriate, but temporal and data completeness issues can effect results. …

Evaporation From Undulating Soil Surfaces Under Turbulent Airflow Through Numerical And Experimental Approaches, Bo Gao, John Farnsworth, Kathleen M. Smits

Civil Engineering Faculty Publications - Archive

Evaporation from undulating soil surfaces is rarely studied due to limited modeling theory and inadequate experimental data linking dynamic soil and atmospheric interactions. The goal of this paper is to provide exploratory insights into evaporation behavior from undulating soil surfaces under turbulent conditions through numerical and experimental approaches. A previously developed and verified coupled free flow and porous media flow model was extended by incorporating turbulent airflow through Reynolds-averaged Navier–Stokes equations. The model explicitly describes the relevant physical processes and the key properties in the free flow, porous media, and at the interface, allowing for the analysis of coupled exchange …

Structural Reinforcement, Reinforced Structural Member And Related Method, Issam E. Harik, Nisal Abheetha Peiris, Drew Christian Thompson, David Cambron Murray, Clayten Nicholas Greenwell

Civil Engineering Faculty Patents

A structural reinforcement includes a plurality of individual reinforcing elements. Each of the plurality of reinforcing elements includes a first end segment, a second end segment and an intermediate segment between the first and second end segments. A support engages the plurality of individual reinforcing elements along the intermediate segments and holds the elements in parallel.

Determination Of The Optimal Location For Constructing Solar Photovoltaic Farms Based On Multi-Criteria Decision System And Dempster–Shafer Theory, Marzieh Mokarram, Mohammad J. Mokarram, Mohammad R. Khosravi, Ali Saber, Akbar Rahideh

Civil and Environmental Engineering and Construction Faculty Research

Considering environmental concerns regarding air pollution which is induced by burning fossil fuels to generate electrical power, utilizing solar energy as a green and sustainable energy source is of great interest. This study proposes a novel framework to determine the optimal location for constructing solar photovoltaic (PV) farms. To locate the suitable areas for PV farms, firstly, a fuzzy-based method is utilized to homogenize the input parameters, thereafter, the analytical hierarchy process (AHP) and Dempster-Shafer (DS) methods are independently used. In the AHP method, the proper weight for each input parameter is generated utilizing a pairwise comparison matrix. However, the …

Space And Depth-Resolved Naturally Occurring Toxic Groundwater Species In Bangladesh And Rwanda: Origination And Risk Analysis, Kenneth Hamilton

Civil and Environmental Engineering Theses and Dissertations

Access to safe potable water is a necessity for all. Groundwater is a commonly relied upon drinking water source for many areas around the world. This is especially true for communities in high density, rural settings. Such is the case for populations near Cox’s Bazaar, Bangladesh, and in the Bugesera region of Rwanda. Sediment and groundwater contamination, through toxic dissolved species, represents a significant public health risk to exposed populations. Tropical soils, such as the soil profiles in Bangladesh and Rwanda, often contain higher concentrations of heavy metals (Rieuwerts, 2007). Additionally, nitrate from fertilizers, are widely used on the soils …

Empirical Models For Predicting Water And Heat Flow Properties Of Permafrost Soils, Michael T. O'Connor, M. Bayani Cardenas, Stephen B. Ferencz, Yue Wu, Bethany T. Neilson, Jingyi Chen, George W. Kling

Publications

Warming and thawing in the Arctic are promoting biogeochemical processing and hydrologic transport in carbon‐rich permafrost and soils that transfer carbon to surface waters or the atmosphere. Hydrologic and biogeochemical impacts of thawing are challenging to predict with sparse information on arctic soil hydraulic and thermal properties. We developed empirical and statistical models of soil properties for three main strata in the shallow, seasonally thawed soils above permafrost in a study area of ~7,500 km² in Alaska. The models show that soil vertical stratification and hydraulic properties are predictable based on vegetation cover and slope. We also show that …

About Computer Simulation Of The Structure Of Cellular Concrete With A Tasked Heat Conductivity, Anvar Ishanovich Adilkhodjayev, S.S. Shaumarov, E.V. Shchipacheva

Journal of Tashkent Institute of Railway Engineers

This article presents the developed mathematical model of the structure of cellular concrete and its computer implementation in the form of a computational software package that allows you to determine pore sizes and characteristics of inter-pore walls, corresponding to the required thermal conductivity of the material. The stages of computer simulation of the macrostructure of cellular concrete are also given.

Calculation Of Hanging Shells Complex Geometry, Sayidmahsud Razzakov, Gennady Fridman, Rasul Khuzhakulov

Journal of Tashkent Institute of Railway Engineers

A method for calculating large-span, spatial hanging shells is presented. A resolving system of equations is obtained for determining the stress-strain state of the hanging shells, the support contour, bearing and stabilizing cables

Plastometry Application For Control Of Portland Cement Consumer Properties, Aleksandr Petrovich Nikolaev, Elena Vladimirovna Kondrashchenko, Valery Іvanovich Kondrashchenko

Journal of Tashkent Institute of Railway Engineers

It was shown that cements of the same strength grade substantially differ at initial dynamics of their interaction with water and structure-forming capacity din the course of stiffening. The necessity was substantiated for current control of Portland cement consumer properties in operation with cement from the same vendor. It was proved that the amount of added plasticizer for obtaining plastisized concrete on the basis of cements of the same strength grade from different vendors may differ several times. The efficiency was demonstrated of input control of Portland cement structure- forming capacity at plants manufacturing concrete and ferroconcrete products, using modified …

Effectiveness Of Seismic Base Isolation In Reinforced Concrete Multi-Storey Buildings, Ravshanbek Abdujabborovich Mavlonov, Sohiba Ergashboevna Numanova

Journal of Tashkent Institute of Railway Engineers

The dynamic reaction of a building to earthquake ground motion is the most critical reason for earthquake actuated damage to structures. The basic concept in seismic isolation is to protect the structure from the damaging effects of an earthquake by introducing a flexible support isolating the building from the shaking ground. Seismic isolation consists of essentially the installation of mechanisms such as isolators which decouple the structure from base. In the present study, the seismic response of the reinforced concrete building, base isolated by lead rubber bearings (LRBs) is compared with the seismic response of the same structure which does …

Method Of Calendar Planning Of Construction Of The Complex At The Early Stage Of Design, M Mirakhmedov, M. Rasulmukhamedov, L.S. Yusupova

Journal of Tashkent Institute of Railway Engineers

The construction schedule developed in the construction organization project does not meet the requirements of the reserve for construction, is not based on the choice of construction and technological schemes and the method of construction organization, therefore, it is not sufficiently reliable, the evidence base stored in the project archive is not confirmed by calculations and Therefore, it cannot be subjected to reliable examination. To eliminate this drawback, a technique is proposed that takes into account the lack of information. The methodology is based on the graphanalytic model of the flow organization of the construction of the complex, which allows …

Adhesion Strength Of Modified Plaster Solutions For Restoration Of Rchitectural Monuments Of Bukhara, M.M. Vaxitov, A.A. Tulaganov, I.I. Tojiev

Journal of Tashkent Institute of Railway Engineers

In this work, the strength of historical mortars of brickwork of the Ismail Somoni mausoleum, the monument of architecture of the Kalyan minaret, the building of the Abdulazizkhan madrasah and the mausoleum of Abdukholik Gizhduvani were determined, and the compressive, tensile, bending and adhesion strengths of the developed modified gypsum mortars for restoration of the above architectural monuments were studied. It is shown that the adhesion strengths of modified gypsum mortars also meet the requirements of KMK 2-01-03-96.

Formation Of A Calculation Model, Study Of Stress-Strain State And Vibrations Of Composite Shell Constructions From Composite Materials, A Abdusattarov, Z.Z. Ergashev, F.E. Abdukadirov

Journal of Tashkent Institute of Railway Engineers

The article gives geometric and physical relationships for shell and ring elements. At the same time, it is assumed that the physical properties of the material of the shell element are described by equations of a viscoelastic medium, taking into account the influence of damage accumulation. Using an approximate method, namely, the “freeze” procedure, a canonical system of equations is obtained - in the form of first-order differential equations with complex coefficients. To solve boundary value problems, the Godunov matrix sweep method is used.

Research Deplanacion Cross-Section, Related To Them Size Under Torsion Fluctuation, Muradov Rustam Muradov, Abduvakhidov Mutakhkhirkhon Abduvakhidov

Journal of Tashkent Institute of Railway Engineers

In this work, the problem of torsional vibrations of rotating working bodies in the form of shafts is studied in case of violation of the assumption of flat sections under torsional strains associated with the peculiarities of torsion deformation of relatively short bodies. During torsional deformation caused by torsional vibrations, the initially rectilinear generators of the cylindrical surfaces of the shaft turn into screw curves of equal length. This causes the longitudinal displacements of their points and, as a result, the appearance of two types of deplanation of its cross sections. The first type of deplanation is associated with the …

Technology For Preparing A Fiber Filler From Rice Straw And Analysis Of Its Interaction With A Modified Gypsum Matrix, Anvar Ishanovich Adilkhodjayev, B.G. Igamberdiev

Journal of Tashkent Institute of Railway Engineers

The article presents research data on a composite material based on rice straw and construction gypsum. An overview of a method for preparing rice straw to increase the dispersion-reinforcing effect of the fiber filler is given. The results of the study of the synergistic effect of the “FremNanogis” modifying additive on the formation of the structure are presented.