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LSU Master's Theses

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Full-Text Articles in Civil and Environmental Engineering

Travel Time Tomographic Imaging Of The Distribution Of The Effective Stress In Clean Sand Under A Model Footing, William M. Tanner Jan 2004

Travel Time Tomographic Imaging Of The Distribution Of The Effective Stress In Clean Sand Under A Model Footing, William M. Tanner

LSU Master's Theses

The use of high-speed data acquisition systems, inexpensive and reliable transducers, and better models of interpretation have combined to make elastic wave tomographic imaging of geotechnical engineering systems easier to accomplish both in the laboratory and in the field. An important application of these developments is that the evaluation of states of effective stress in soils using images of elastic wave velocity distribution. As a consequence, it is possible to experimentally estimate the state of induced and in-situ effective stresses and to compare these results with established models of stress distribution based on the theory of elasticity (e.g., Boussinesq’s solution). …

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Biological Treatment Of Industrial Wastewater Containing High Concentrations Of Linear Alkylbenzene Sulfonate (Las), Luis Alberto Espinoza Jan 2004

Biological Treatment Of Industrial Wastewater Containing High Concentrations Of Linear Alkylbenzene Sulfonate (Las), Luis Alberto Espinoza

LSU Master's Theses

Lauryl Alkylbenzene Sulfonate (LAS) is the major anionic surfactant used worldwide in detergent and household cleaning product formulations. Its biodegradation and removal has been extensively studied in wastewater treatment facilities and laboratory-scale tests at low concentrations (<10 mg/L) typical of those encountered in municipal wastewater treatment plants. Less effort, however, has been expended investigating degradation of higher concentrations of LAS representative of those expected in wastewater generated at LAS manufacturing operations. The research described in this thesis was conducted to study biological processes for treating wastewaters containing high concentrations (e.g., 400 mg/L) of LAS. Initial experiments were carried out using a respirometry technique, and subsequently, three different laboratory-scale bioreactor systems. The three systems studied were a Sequencing Batch Reactor (SBR), a Sequencing Batch Biofilm Reactor (SBBR), and an Intermittent Cycle Extension Aeration System (ICEAS). The SBR and ICEAS were operated on a five-day cycle basis with a hydraulic retention time of four days. The SBBR was operated mainly in a two-day cycle having a hydraulic retention time of ten days as well, and polyurethane foam cubes were used as a support medium for attached biomass growth. The three systems were compared on their ability to remove LAS measured in terms of total organic carbon (TOC) and methylene blue active substances (MBAS). The reactors were also compared on the basis of foam production. The ICEAS showed the best performance in terms of controllable foam production while exhibiting a capacity for effectively dealing with transient periods of elevated loading. When a short Fill period was used, the SBR and SBBR had the disadvantage of producing excessive foaming, and an intermittent aeration strategy was required avoid overflow.

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Modeling Of River Hydrodynamics And Active Cap Effectiveness In The Anacostia River, Keegan L. Roberts Jan 2004

Modeling Of River Hydrodynamics And Active Cap Effectiveness In The Anacostia River, Keegan L. Roberts

LSU Master's Theses

The Anacostia Active Capping Project (AACP) is a United States Environmental Protection Agency (EPA) funded initiative to develop and implement, on a field scale, active capping barrier technologies. Overseen by the Hazardous Substance Research Center, South and Southwest (HSRC), the AACP plans to demonstrate the ability of active capping barrier technologies to prevent the migration of contaminants from the sediment bed to the overlying water column of the Anacostia River. The demonstration project will involve the placement and monitoring of four individual types of capping materials (apatite, Aquablok, coke breeze, and sand) and the monitoring of one control (i.e. uncapped) …

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Experimental And Computational Modeling Of Granular Materials, Orlando Boscan Jan 2004

Experimental And Computational Modeling Of Granular Materials, Orlando Boscan

LSU Master's Theses

4-inch cubical sand specimens were been tested under drained conditions using a wide range of stress paths. The testing was performed by means of a true (cubical) triaxial device that has been conditioned for this study. This testing set-up consisted of a servo-controlled, single-boundary type apparatus, with six flexible membranes that create a center cavity surrounding the soil specimens. This thesis illustrates the functioning of the triaxial device, including detailed descriptions of the device components, sample preparation, and a practical application related to the mechanical characterization of granular materials using critical state soil mechanics. An experimental program, based on the …

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The Determination Of Appropriate Phosphogypsum: Class C Fly Ash : Portland Type Ii Cement Compositions For Use In Marine Applications, Pradyot Sudhakar Deshpande Jan 2003

The Determination Of Appropriate Phosphogypsum: Class C Fly Ash : Portland Type Ii Cement Compositions For Use In Marine Applications, Pradyot Sudhakar Deshpande

LSU Master's Theses

Phosphogypsum (PG, CaSO4·2H2O) is a waste by-product produced during the wet manufacturing phosphoric acid process. Phosphoric acid is manufactured by processing phosphate rock that contains relatively high concentrations of naturally occurring radioactive impurities which makes PG a radioactive material. PG also contains certain trace metals including As, Ba, Cd, Cr and Pb and radioactive contaminants such as Radium226 and Uranium238 that pose potential hazard to human health and the environment. According to USEPA, the current allowable disposal method for PG is stack piling. This research was focused on stabilizing PG with Portland Type II …

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Mathematical Modeling Analysis Of Floating Bead Biofilter Applications To Domestic Wastewater Treatment, Qiang Wu Jan 2003

Mathematical Modeling Analysis Of Floating Bead Biofilter Applications To Domestic Wastewater Treatment, Qiang Wu

LSU Master's Theses

Floating Bead Biofilters (FBFs) have been applied to aquacultural recirculating tanks and domestic wastewater treatment systems for controlling total ammonia nitrogen (TAN), biochemical oxygen demand (BOD), and total suspended solids (TSS). Support modified media in these FBFs provide a large surface area (1150~1475 m2/m3) so that the active biofilm can be retained in the FBF by attaching to the media surface. Understanding the theories involved in biofilm processes greatly helps in sizing, designing, and modeling of FBF systems. Fundamental biofilm processes like mass transport of various substrates into the biofilm and the substrate utilization within the biofilm were studied. A …

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Evaluation Of Static Low Density Media Filters For Use In Domestic Wastewater Treatment, Cynthia Wagener Jan 2003

Evaluation Of Static Low Density Media Filters For Use In Domestic Wastewater Treatment, Cynthia Wagener

LSU Master's Theses

Static Low Density Media (SLDM) filters are submerged granular medium filters that contain a static matrix of floating media. These filters provide concurrent biological and physical treatment, and are therefore classified as bioclarifiers. Through different design and operation strategies, SLDM filters may be used for a variety of functions such as: solid-liquid separation alone, organic conversion and solids capture, nitrification and solids capture, and denitrification and solids capture. For operation as an aerobic unit, an external aeration strategy was developed to preserve the static nature of the bed. In this study, SLDM filters treated a highly variable flow domestic wastewater …

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A Hybrid Model-Based And Memory-Based Short-Term Traffic Prediction System, Ciprian Danut Alecsandru Jan 2003

A Hybrid Model-Based And Memory-Based Short-Term Traffic Prediction System, Ciprian Danut Alecsandru

LSU Master's Theses

Short-term traffic forecasting capabilities on freeways and major arterials have received special attention in the past decade due primarily to their vital role in supporting various travelers' trip decisions and traffic management functions. This research presents a hybrid model-based and memory-based methodology to improve freeway traffic prediction performance. The proposed methodology integrates both approaches to strengthen predictions under both recurrent and non-recurrent conditions. The model-based approach relies on a combination of static and dynamic neural network architectures to achieve optimal prediction performance under various input and traffic condition settings. Concurrently, the memory-based component is derived from the data archival system …

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Staying Afloat: A Risk Analysis Study Of Flooding In South Louisiana, Marlene Tomaszkiewicz Jan 2003

Staying Afloat: A Risk Analysis Study Of Flooding In South Louisiana, Marlene Tomaszkiewicz

LSU Master's Theses

For decades, South Louisiana has been battling with flood risk. The area has been inundated with flood waters several times, whether it is due to tropical weather, strong rainfall events, or rising waters. This has resulted in millions of dollars in damages, and in some instances, the same home has been affected multiple times. Many agree that South Louisiana is just not a livable area to begin with; the risk is just too great. However, abandoning the area is simply not an option. As a result, the flood risk battle ensues. How much risk are we talking about? The Federal …

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Development Of A Performance-Based Design Approach And Related Loads For Facilities Designated As Essential During A Hurricane Event, Joffrey Elliott Easley Jan 2003

Development Of A Performance-Based Design Approach And Related Loads For Facilities Designated As Essential During A Hurricane Event, Joffrey Elliott Easley

LSU Master's Theses

Historically, shelters and other facilities designated as "essential" during hurricanes have experienced unacceptable damage during recent hurricanes, exposing the occupants to uncomfortable and dangerous conditions. One of the reasons for this is the lack of standards or design guidelines addressing the special considerations required for such facilities. A new approach to the design of essential facilities in hurricane regions is proposed. The goal of this work is to create a tool for improving the safety and serviceability of evacuation shelters and other critical facilities utilized during hurricane events. This is achieved by developing a new philosophy based on selection of …

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Analysis Of Laboratory And Field Pull-Out Tests Of Geosynthetics In Clayey Soils, Ather Mohiuddin Jan 2003

Analysis Of Laboratory And Field Pull-Out Tests Of Geosynthetics In Clayey Soils, Ather Mohiuddin

LSU Master's Theses

Soil reinforcement interaction is a key issue in the design of reinforced soil structures. Therefore, it is important to analyze the pull-out mechanism, and to evaluate the interaction between the soil and geosynthetic reinforcement. Majority of pull-out tests performed to date were in granular soils, and very few tests were reported in cohesive soils. The shortage of in-situ granular materials and the availability of cohesive soils in Louisiana have initiated a growing interest in using the marginal soils as backfill material. To investigate the soil-geosynthetic interaction parameters, series of laboratory and field pull-out tests were conducted using various geosynthetics (geogrids: …

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Dechlorination Of 1,2,3,4-Tetrachlorobenzene In Organic Matter- And Mineral-Dominated Soils And Effects Of Typha Latifolia Roots, Lizhu Lin Jan 2003

Dechlorination Of 1,2,3,4-Tetrachlorobenzene In Organic Matter- And Mineral-Dominated Soils And Effects Of Typha Latifolia Roots, Lizhu Lin

LSU Master's Theses

A variety of environments are contaminated with chlorinated benzenes. Therefore, investigating the biodegradation of chlorobenzenes in different types of soils is useful in assessing the feasibility of bioremediation. One mineral-dominated soil: PPI (Petro Processors Inc. site) soil, and three organic matter-dominated soils (natural wetland soil, constructed wetland soil (a mixture of peat, compost and sand), and river sediment) were used to investigate anaerobic biodegradation of 1,2,3,4-Tetrachlorobenzene (1,2,3,4-TeCB) using laboratory microcosms. To determine whether methanogens were directly responsible for dechlorination, a comparative study using 2-bromoethanesulfonic acid (BES) for inhibition of methanogenesis was conducted. Hydrogen and methane concentrations, and microbial diversities were …

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Exploring Geometric, Kinematic And Behavioral Scalability Of Microscopic Traffic Simulation Systems, Srikanth Chakravarthy Jan 2003

Exploring Geometric, Kinematic And Behavioral Scalability Of Microscopic Traffic Simulation Systems, Srikanth Chakravarthy

LSU Master's Theses

Even with today's remarkable advancement in computing power, microscopic simulation modeling remains a computationally intensive process that imposes limitations on its potential use for modeling large-scale transportation networks. Research and practice have repeatedly demonstrated that microscopic simulation runs can be excessively time-consuming, depending on the network size, the number of simulated entities (vehicles), and the computational resources available. While microscopic features of a simulated system collectively define the overall system characteristics, it is argued that the microscopic simulation process itself is not necessarily free of redundancy, which if reduced, could substantially improve the computational efficiency of simulation systems without compromising …

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Laboratory Evaluation Of In-Situ Tests As Potential Quality Control/Quality Assurance Tools, Ekrem Seyman Jan 2003

Laboratory Evaluation Of In-Situ Tests As Potential Quality Control/Quality Assurance Tools, Ekrem Seyman

LSU Master's Theses

There are new in-situ test devices such as the Geogauge, Light Falling Weight Deflectometer (LFWD) and Dynamic Cone Penetrometer (DCP). Unlike the nuclear density gauge, the new methods provide measurements based on the engineering properties (strength/stiffness) of soil instead of physical properties like field density and moisture content. However the geogauge, LFWD and the DCP are not yet proven to be reliable and the correlations of these tests with standard tests are limited. An extensive laboratory investigation was carried out to evaluate the Geogauge, LFWD and DCP as potential tests to measure in-situ stiffness of highway materials and embankments. In …

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Wind Loads On Multiple Cylinders Arranged In Tandem With Effects Of Turbulence And Surface Roughness, Xianzhi Liu Jan 2003

Wind Loads On Multiple Cylinders Arranged In Tandem With Effects Of Turbulence And Surface Roughness, Xianzhi Liu

LSU Master's Theses

The goal of this study is to investigate the characteristics of mean drag and lift forces for a series of cylinders arranged in tandem with varying flow turbulence and surface roughness. This goal was fulfilled by building a wind tunnel test section capable of generating both smooth flow and turbulent flow, and by adopting cylinder models with certain types of surface roughness as well as the smooth surface. In both smooth flow and grid-turbulence flow conditions, single cylinders as well as multiple cylinders were tested. The tested Reynolds number ranged from 2.7×104 to 8.6×104. For multiple-cylinder tests, a majority of …

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Computational Model For Heat Transfer In The Human Eye Using The Finite Element Method, Umit Cicekli Jan 2003

Computational Model For Heat Transfer In The Human Eye Using The Finite Element Method, Umit Cicekli

LSU Master's Theses

In this work a finite element model for the human eye presented. Thermal analysis was done in order to capture the temperature variation in the human eye. The model was created using advance finite element program ABAQUS. In the model each of the eye's component (cornea, sclera, lens, iris, aqueous and vitreous humor) has own material property. Specific boundary conditions were used for the model. The model incorporates the interaction between eyes components. The Comparisons were done with the available experimental results. The results show that there is a temperature variation in the human eye components with the increasing the …

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Contraflow Evacuation On The Westbound I-10 Out Of The City Of New Orleans, Gregoris Theodoulou Jan 2003

Contraflow Evacuation On The Westbound I-10 Out Of The City Of New Orleans, Gregoris Theodoulou

LSU Master's Theses

In this study, CORSIM 5.0 simulation model results were used to evaluate the effectiveness of the contraflow segment on westbound I-10 out of the City of New Orleans. The Louisiana State Police plan for the contraflow segment was used to construct the CORSIM network. Alternative plans were also developed in this study to compare the effectiveness of the contraflow operation. With the use of CORSIM, traffic flow on the contraflow segment was determined based on the amount of evacuating vehicles leaving the exit nodes. In addition the time and speed to travel the contraflow segment was estimated. The results showed …

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The Fate Of Nitrogen In The Marshland Upwelling System, Jeremy Fontenot Jan 2003

The Fate Of Nitrogen In The Marshland Upwelling System, Jeremy Fontenot

LSU Master's Theses

The Marshland Upwelling System (MUS) is an alternative method for coastal dwellers to treat their wastewater. Past studies have dealt with the removal of fecal pathogens from wastewater. However the objectives of this research were to: 1) evaluate the treatment capability of the MUS under high hydraulic loadings and cool temperatures with respect to CBOD5, TKN, TAN, NO2--N, NO3--N, TP, and PO4-P, and 2) determine the ideal flowrate and injection frequency to achieve satisfactory nitrogen removal without hydraulic failure. The artificial wastewater study was performed to evaluate the treatment of …

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A Screening Assessment Of Solidification/Stabilization For Storm Water Residuals, Erin Ezell Krielow Jan 2003

A Screening Assessment Of Solidification/Stabilization For Storm Water Residuals, Erin Ezell Krielow

LSU Master's Theses

Metal species infused particulate matter associated with urban rainfall-runoff is a unique and profuse source of pollution. Generated from urban activities, such as traffic activity and vehicular/infrastructure abrasion, contaminated residual material is deposited to roadways during dry weather and transported to surrounding environments and/or best management practice (BMP) treatment facilities during wet-weather events. These particulates range in size from 1 ƒÝm to 10000 ƒÝm and are contaminated with metal species that originate from such sources as vehicular body wear (Cu), tire wear (Zn), and brake dust (Pb). Depending on the efficiencies of the BMP treatment facilities, these containment systems have …

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A Methodology For Deriving Performance Measures From Spatio-Temporal Traffic Contour Maps Using Digital Image Analysis Procedures, Prashanth Kotha Jan 2003

A Methodology For Deriving Performance Measures From Spatio-Temporal Traffic Contour Maps Using Digital Image Analysis Procedures, Prashanth Kotha

LSU Master's Theses

The main focus of this study is to improve the data analysis tools used in performance monitoring and level of service assessment of freeway systems. The proposed study presents a methodology to develop new second-order statistical measures that are derived from texture characterization techniques in the field of digital image analysis. The new measures are capable of extracting properties such as smoothness, homogeneity, regularity, and randomness in traffic behavior from the spatio-temporal traffic contour maps. To study the new performance measures a total of 14270, 15-min traffic contour maps were generated for a section of 3.4 miles of I-4 in …

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Experimental Evaluation Of Temporal Particle Agglomeration And Metal Partitioning Of Urban Rainfall-Runoff, Aimee Ann Blazier Jan 2003

Experimental Evaluation Of Temporal Particle Agglomeration And Metal Partitioning Of Urban Rainfall-Runoff, Aimee Ann Blazier

LSU Master's Theses

Rainfall-runoff quantity and quality control presents unique challenges due to the complexity and variability of hydrology and rainfall-runoff chemistry as well as the variable nature of constituent-producing processes in the environment. This study investigates two fundamental processes in rainfall-runoff: temporal particle agglomeration and metal partitioning between the solid and aqueous phase. A series of rainfall-runoff events were captured at an urban, Portland concrete cement (PCC) paved site in Baton Rouge, Louisiana and characterized with respect to particle gradation and metal phase fractions (dissolved and particulate) over time from a well-mixed, batch experimental system. Results indicate that equilibria and kinetics of …

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Modeling And Evaluating Evacuation Contraflow Termination Point Designs, Yu Yik Lim Jan 2003

Modeling And Evaluating Evacuation Contraflow Termination Point Designs, Yu Yik Lim

LSU Master's Theses

Prior studies showed that most evacuation contraflow designs have never been implemented. As a result, the effectiveness of these contraflow termination point designs remains unknown. To address this problem, a microscopic traffic simulation tool, CORSIM 5.0, was used. Ten simulation models were conducted and determined the factors that affect traffic operations in the vicinity of the various planned contraflow termination point with median crossover designs. The performance of various models was ranked by statistical test in terms of the total number of vehicles processed, traffic flow, speed, density and delay. The results that were based on theoretical simulations and assumptions …

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Treatment Of Mixtures Of Methyl Ethyl Ketone (Mek) And Toluene Using Continuous And Sequencing Batch Operated Biofilters, Jorge C. Atoche Jan 2003

Treatment Of Mixtures Of Methyl Ethyl Ketone (Mek) And Toluene Using Continuous And Sequencing Batch Operated Biofilters, Jorge C. Atoche

LSU Master's Theses

During the past decade, biofiltration has increasingly been applied as an air pollution control technology to minimize or eliminate emissions of volatile organic compounds from industrial sources. Although of the ability of this technology to maintain high removal efficiency during relatively steady conditions has been well established for many waste streams, a limitation of this technology has been its inability to maintain high removal efficiency during transient loading conditions typical of industrial operations. In the research described herein, a conventional continuous-flow biofilter (CFB) and a sequencing batch biofilter (SBB) were operated for more than 295 days to treat a model …

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Strength Properties Of Granular Materials, Brenda Novoa-Martinez Jan 2003

Strength Properties Of Granular Materials, Brenda Novoa-Martinez

LSU Master's Theses

This thesis presents the results of the experimental work conducted on glass beads in order to investigate the effects of particle size, confining pressure, and surface roughness on the strength properties of the particulate media. Conventional triaxial compression tests were conducted to investigate those effects. Three different sizes of beads were tested: small (diameter = 0.75 – 1.00 mm), medium (diameter = 1.55 – 1.85 mm), and large (diameter = 3.30 – 3.60 mm). The glass beads were subjected to three different confining pressures: 25-, 100-, and 400-kPa. Smooth and etched beads were tested; the etched surface was achieved by …

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Assessing Sample Bias And Establishing Standardized Procedures For Weighting And Expansion Of Travel Survey Data, Fahmida Nilufar Jan 2003

Assessing Sample Bias And Establishing Standardized Procedures For Weighting And Expansion Of Travel Survey Data, Fahmida Nilufar

LSU Master's Theses

Recent household travel surveys are encountering problems with non-response, non-coverage, non-reporting, and even incorrect or incomplete reporting of trips. In addition, data from survey samples are affected by the social, and economic conditions of the respondents, as well as the survey instrument used to collect the data. As a result, household travel survey data are invariably associated with some level of bias. These threats to the integrity of the data are often ignored while analyzing the sample survey data. However, considering the importance of information derived from such surveys, it is necessary that the survey must provide an accurate reflection …

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Field Evaluation Of In-Situ Test Technology For Qc/Qa During Construction Of Pavement Layers And Embankments, Munir Darwish Nazzal Jan 2003

Field Evaluation Of In-Situ Test Technology For Qc/Qa During Construction Of Pavement Layers And Embankments, Munir Darwish Nazzal

LSU Master's Theses

With the coming changes from an empirical to mechanistic-empirical pavement design, it becomes essential to move towards changing the quality control/quality assurance (QC/QA) procedures of compacted materials from a unit weight-based criterion to a stiffness/strength based criterion. The non-destructive in-situ tests such as Geogauge, Dynamic Cone Penetrometer (DCP), and Light Falling Weight Deflectometer (LFWD) can be used as effective tools in the assessment of subsurface conditions and in evaluating the stiffness of pavement materials and embankment. This thesis evaluates the potential use of these three devices to reliably measure the stiffness characteristics of highway materials for possible application in the …

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Modeling A Mississippi River Diversion Into A Louisiana Wetland, Stephan Alexander Capps Jan 2003

Modeling A Mississippi River Diversion Into A Louisiana Wetland, Stephan Alexander Capps

LSU Master's Theses

Wetland loss has significant impacts. Numerous loss mechanisms have been hypothesized, and a greater number of solutions have been proposed. One proposed solution is to divert river water into a degraded area with the intent of increasing sedimentation, introducing nutrients, and/or decreasing salinity within the wetland. However, wetland hydraulics and hydrology are complex processes and any hydrologic modification may result in unintended consequences. Predicting these consequences can be problematic due to the complexity and difficulty associated with proper modeling of the hydraulics and topography. The primary objective of this study is to evaluate the suitability of established one- and two-dimensional …

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Assessing The Feasibility Of Supplying Vehicle Activity Data To Mobile6 Using The Global Positioning System (Gps), Srinivas Varanasi Jan 2003

Assessing The Feasibility Of Supplying Vehicle Activity Data To Mobile6 Using The Global Positioning System (Gps), Srinivas Varanasi

LSU Master's Theses

MOBILE6 is a software program developed by the U.S. Environmental Protection Agency (EPA) to estimate current and future vehicle emissions. The EPA requires all states to develop emission inventories for State Implementation Plans (SIPs) and to demonstrate conformity in non-attainment areas. The primary objective of the MOBILE models is to develop emission inventories in compliance with EPA’s regulations. The research reported in this study is primarily a proof-of-concept study of the feasibility of the Global Positioning System (GPS) to supply vehicle activity data to MOBILE6. However, it also deals with identifying vehicle registration input to MOBILE6 using non-GPS sources. Input …

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The Interaction Between Hydrology And Water Quality For Urban Rainfall-Runoff: Implications For Management Strategies, Christopher Michael Dean Jan 2002

The Interaction Between Hydrology And Water Quality For Urban Rainfall-Runoff: Implications For Management Strategies, Christopher Michael Dean

LSU Master's Theses

In urban environments, anthropogenic activity deposits potentially hazardous residuals onto impervious surfaces. To investigate the process of wet-weather constituent transport, twelve rainfall/runoff events collected at an experimental catchment site in Baton Rouge, Louisiana were analyzed for temporal delivery of aggregate constituents (SSC, COD, TDS) as well as dissolved and particulate-bound metal concentrations (Cd, Cu, Pb and Zn). Event mean concentrations for the parameters analyzed often exceeded USEPA discharge limits. Rainfall-runoff events were characterized as either mass-limited or flow-limited. Events designated as mass-limited exhibited a high runoff volume, low vehicle to volume ratio (VPV), high stream power and a low correlation …

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Fine Aggregate Characterization Using Digital Image Analysis, Tongyan Pan Jan 2002

Fine Aggregate Characterization Using Digital Image Analysis, Tongyan Pan

LSU Master's Theses

A comprehensive literature review shows that performance of hot mix asphalt (HMA) is influenced by properties of aggregate. Current situation is that only limited efforts were dedicated to aggregate tests and criteria on aggregate, compared to researches on new binder tests, especially to that of fine aggregate. Superpave (Superior Performing Asphalt Pavement) tests/criteria on aggregate need to reflect those properties that influence performance. Representatives of the aggregate industry and the Superpave Mixture/Aggregate ETG (Expert Task Group) have reached the consensus for the need to improve aggregate tests and criteria as one of the most needed aspects left to complete in …

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