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Civil Engineering Faculty Publications and Presentations

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Full-Text Articles in Civil Engineering

Developing A Non-Cooperative Optimization Model For Water And Crop Area Allocation Based On Leader-Follower Game, Abbas Sedghamiz, Mohammad Reza Nikoo, Manouchehr Heidarpour, Mojtaba Sadegh Dec 2018

Developing A Non-Cooperative Optimization Model For Water And Crop Area Allocation Based On Leader-Follower Game, Abbas Sedghamiz, Mohammad Reza Nikoo, Manouchehr Heidarpour, Mojtaba Sadegh

Civil Engineering Faculty Publications and Presentations

In this paper, a mathematical model for conflict resolution among a diverse set of agricultural water users in Golestan province, Iran, is developed. Given the bi-level nature of the distribution of power in the current problem, a combination of Leader–Follower game and Nash–Harsanyi bargaining solution method is employed to find optimal water and crop area allocations. The Golestan Regional Water Authority is the leader in this setting, controlling the total water allocations; and the agricultural sectors are the followers, competing over the allocated water. Two objectives for the leader are (i) maximizing profits, and (ii) maximizing share of green water …

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A New Normal For Streamflow In California In A Warming Climate: Wetter Wet Seasons And Drier Dry Seasons, Iman Mallakpour, Mojtaba Sadegh, Amir Aghakouchak Dec 2018

A New Normal For Streamflow In California In A Warming Climate: Wetter Wet Seasons And Drier Dry Seasons, Iman Mallakpour, Mojtaba Sadegh, Amir Aghakouchak

Civil Engineering Faculty Publications and Presentations

In this study, we investigate changes in future streamflows in California using bias-corrected and routed streamflows derived from global climate model (GCM) simulations under representative concentration pathways (RCPs): RCP4.5 and RCP8.5. Unlike previous studies that have focused mainly on the mean streamflow, annual maxima or seasonality, we focus on projected changes across the distribution of streamflow and the underlying causes. We report opposing trends in the two tails of the future streamflow simulations: lower low flows and higher high flows with no change in the overall mean of future flows relative to the historical baseline (statistically significant at 0.05 level). …

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Understanding Track Substructure Behavior: Field Instrumentation Data Analysis And Development Of Numerical Models, Huseyin Boler, Debakanta Mishra, Wenting Hou, Erol Tutumluer Dec 2018

Understanding Track Substructure Behavior: Field Instrumentation Data Analysis And Development Of Numerical Models, Huseyin Boler, Debakanta Mishra, Wenting Hou, Erol Tutumluer

Civil Engineering Faculty Publications and Presentations

Numerous studies have targeted using numerical modeling, field instrumentation, or combinations of both to gain insight into track substructure behavior under loading. In-depth understanding of track substructure behavior serving both passenger and freight trains is critical to developing suitable design and maintenance/rehabilitation methods to ensure adequate performance under loading. This manuscript presents findings from a recently completed study involving advanced instrumentation and numerical modeling to investigate track substructure-related issues at several problematic railroad bridge approaches in the United States. Multi-Depth Deflectometers (MDDs) were installed to measure transient as well as plastic deformations experienced by track substructure layers under loading. Strain …

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A Hybrid Clustering-Fusion Methodology For Land Subsidence Estimation, Narges Taravatrooy, Mohammad Reza Nikoo, Mojtaba Sadegh, Mohammad Parvinnia Nov 2018

A Hybrid Clustering-Fusion Methodology For Land Subsidence Estimation, Narges Taravatrooy, Mohammad Reza Nikoo, Mojtaba Sadegh, Mohammad Parvinnia

Civil Engineering Faculty Publications and Presentations

A hybrid clustering-fusion methodology is developed in this study that employs Genetic Algorithm (GA) optimization method, k-means method, and several soft computing (SC) models to better estimate land subsidence. Estimation of land subsidence is important in planning and management of groundwater resources to prevent associated catastrophic damages. Methods such as the Persistent Scatterer Interferometric Synthetic Aperture Radar (PS-InSAR) can be used to estimate the subsidence rate, but PS-InSAR does not offer the required efficiency and accuracy in noisy pixels (obtained from remote sensing). Alternatively, a fusion-based methodology can be used to estimate subsidence rate, which offers a superior accuracy as …

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Effect Of Geogrid Reinforcement On Railroad Ballast Performance Evaluated Through Triaxial Testing And Discrete Element Modeling, Yu Qian, Erol Tutumluer, Debakanta Mishra, Hasan Kazmee Nov 2018

Effect Of Geogrid Reinforcement On Railroad Ballast Performance Evaluated Through Triaxial Testing And Discrete Element Modeling, Yu Qian, Erol Tutumluer, Debakanta Mishra, Hasan Kazmee

Civil Engineering Faculty Publications and Presentations

Geogrids have been found to effectively improve the performance of unbound aggregate layers in transportation applications by providing confinement and arresting movement through interlock between individual aggregate particles and their apertures. Geogrid reinforcement offers an effective remedial measure when railroad track structures are susceptible to track geometry defects resulting from excessive movement and particle reorientation within the ballast layer. This paper presents an ongoing research study at the University of Illinois aimed at quantifying the effects of geogrid reinforcement on the shear strength and permanent deformation behavior of railroad ballast. Geogrids with triangular, rectangular, and square apertures were tested in …

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Optimal And Objective Placement Of Sensors In Water Distribution Systems Using Information Theory, Mohammad S. Khorshidi, Mohammad Reza Nikoo, Mojtaba Sadegh Oct 2018

Optimal And Objective Placement Of Sensors In Water Distribution Systems Using Information Theory, Mohammad S. Khorshidi, Mohammad Reza Nikoo, Mojtaba Sadegh

Civil Engineering Faculty Publications and Presentations

Optimization-based deployment of contamination warning system in water distribution systems has been widely used in the literature, due to their superior performance compared to rule- and opinion-based approaches. However, optimization techniques impose an excessive computational burden, which in turn is compensated for by shrinking the problem’s decision space and/or using faster optimization algorithms with less accuracy. This imposes subjectivity in interpretation of the system and associated risks, and undermines model’s accuracy by not exploring the entire feasible space. We propose a framework that uses information theoretic techniques, including value of information and transinformation entropy, for optimal sensor placement. This can …

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Climate-Informed Environmental Inflows To Revive A Drying Lake Facing Meteorological And Anthropogenic Droughts, Mojtaba Sadegh Aug 2018

Climate-Informed Environmental Inflows To Revive A Drying Lake Facing Meteorological And Anthropogenic Droughts, Mojtaba Sadegh

Civil Engineering Faculty Publications and Presentations

The rapid shrinkage of Lake Urmia, one of the world’s largest saline lakes located in northwestern Iran, is a tragic wake-up call to revisit the principles of water resources management based on the socio-economic and environmental dimensions of sustainable development. The overarching goal of this paper is to set a framework for deriving dynamic, climate-informed environmental inflows for drying lakes considering both meteorological/climatic and anthropogenic conditions. We report on the compounding effects of meteorological drought and unsustainable water resource management that contributed to Lake Urmia’s contemporary environmental catastrophe. Using rich datasets of hydrologic attributes, water demands and withdrawals, as well …

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Investigating The Pavement Vibration Response For Roadway Service Condition Evaluation, Zhoujing Ye, Yang Lu, Linbing Wang Jul 2018

Investigating The Pavement Vibration Response For Roadway Service Condition Evaluation, Zhoujing Ye, Yang Lu, Linbing Wang

Civil Engineering Faculty Publications and Presentations

Dynamic response of pavement provides service condition information and helps with damage prediction, while limited research is available with the simulation of pavement vibration response for evaluating roadway service condition. +is paper presents a numerical model for the analysis of the pavement vibration due to the dynamic load created by a passing vehicle. A quarter vehicle model was used for the determination of the vehicle moving load. Both random and spatial characteristics of the load were considered. The random nonuniform moving load was then introduced in a 3D finite element model for the determination of the traffic-induced pavement vibration. The …

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Multihazard Scenarios For Analysis Of Compound Extreme Events, Mojtaba Sadegh Jun 2018

Multihazard Scenarios For Analysis Of Compound Extreme Events, Mojtaba Sadegh

Civil Engineering Faculty Publications and Presentations

Compound extremes correspond to events with multiple concurrent or consecutive drivers (e.g., ocean and fluvial flooding, drought, and heat waves) leading to substantial impacts such as infrastructure failure. In many risk assessment and design applications, however, multihazard scenarios of extremes and compound events are ignored. In this paper, we review the existing multivariate design and hazard scenario concepts and introduce a novel copula-based weighted average threshold scenario for an expected event with multiple drivers. The model can be used for obtaining multihazard design and risk assessment scenarios and their corresponding likelihoods. The proposed model offers uncertainty ranges of most likely …

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Closure To The Discussion Of “Long-Term Performance Of A Highway Embankment Build With Lightweight Aggregates”, Anand J. Puppala, Sireesh Saride, Raja V. Yenigalla, Bhaskar C. S. Chittoori, Ekarut Archeewa Jun 2018

Closure To The Discussion Of “Long-Term Performance Of A Highway Embankment Build With Lightweight Aggregates”, Anand J. Puppala, Sireesh Saride, Raja V. Yenigalla, Bhaskar C. S. Chittoori, Ekarut Archeewa

Civil Engineering Faculty Publications and Presentations

The authors thank Dr. Diyaljee for his interest on the subject and providing assessments based on the two research articles (Saride et al. 2010 and Puppala et al. 2017). Authors appreciate the comprehensive analysis done in the discussion. Following the comments noted in the discussion, we would like to provide our explanations on the discussion.

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Shuffled Complex-Self Adaptive Hybrid Evolution (Sc-Sahel) Optimization Framework, Mojtaba Sadegh Jun 2018

Shuffled Complex-Self Adaptive Hybrid Evolution (Sc-Sahel) Optimization Framework, Mojtaba Sadegh

Civil Engineering Faculty Publications and Presentations

Simplicity and flexibility of meta-heuristic optimization algorithms have attracted lots of attention in the field of optimization. Different optimization methods, however, hold algorithm-specific strengths and limitations, and selecting the best-performing algorithm for a specific problem is a tedious task. We introduce a new hybrid optimization framework, entitled Shuffled Complex-Self Adaptive Hybrid EvoLution (SC-SAHEL), which combines the strengths of different evolutionary algorithms (EAs) in a parallel computing scheme. SC-SAHEL explores performance of different EAs, such as the capability to escape local attractions, speed, convergence, etc., during population evolution as each individual EA suits differently to various response surfaces. The SC-SAHEL algorithm …

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Ltpp Data Analysis: Factors Affecting Pavement Roughness For The State Of California, Pedro Zavanga, Alisha Khanal, Mena I. Souliman May 2018

Ltpp Data Analysis: Factors Affecting Pavement Roughness For The State Of California, Pedro Zavanga, Alisha Khanal, Mena I. Souliman

Civil Engineering Faculty Publications and Presentations

The contributions of pavement structure and features, rehabilitation techniques, climatic conditions, traffic levels, layer materials and properties, pavement distress, and other factors causing changes in pavement smoothness are not well documented. As a result, it becomes difficult to select the appropriate pavement structure, design features and rehabilitation strategies to ensure pavement smoothness. This study focuses on analysing the available LTPP data for asphalt pavements in California by investigating the correlation between the pavement roughness and the effect of pavement temperature, precipitation, fatigue, age of pavement, rutting, and the average annual daily truck traffic. IRI has been identified as the factor …

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The Quest For Hydrological Signatures: Effects Of Data Transformation On Bayesian Inference Of Watershed Models, Mojtaba Sadegh, Morteza Shakeri Majd, Jairo Hernandez, Ali Torabi Haghighi Mar 2018

The Quest For Hydrological Signatures: Effects Of Data Transformation On Bayesian Inference Of Watershed Models, Mojtaba Sadegh, Morteza Shakeri Majd, Jairo Hernandez, Ali Torabi Haghighi

Civil Engineering Faculty Publications and Presentations

Hydrological models contain parameters whose values cannot be directly measured in many field-scale projects, hence need to be meaningfully inferred through calibration against historical records. Much progress has been made in development of efficient search algorithms in order to find optimal parameter values and their underlying uncertainty distributions. Yet, relatively little is known about the effects of calibration data (or error residual) transformations on the identifiability of model parameters and reliability of model predictions. Effects of calibration data transformations on the posterior parameter distribution and predictive capability of two parsimonious hydrological models are analyzed herein. Our results depict that calibration …

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A Digital Image Analysis Of Gravel Aggregate Using Ct Scanning Technique, Jiangfeng Wu, Linbing Wang, Yue Hou, Haocheng Xiong, Yang Lu, Lei Zhang Mar 2018

A Digital Image Analysis Of Gravel Aggregate Using Ct Scanning Technique, Jiangfeng Wu, Linbing Wang, Yue Hou, Haocheng Xiong, Yang Lu, Lei Zhang

Civil Engineering Faculty Publications and Presentations

Particle shape was one of the most important factors which affects the gravel aggregate’s properties. It was also one of the important factors that directly affects the performance of asphalt pavements. In this paper, the gravel aggregate of quartzite was studied by using the industrial CT instrument. MATLAB was used to capture the aggregate slice properties including reverse color, median filtering, noise reduction, binarization and so on. The 3D aggregate model was reconstructed by using the software of MIMICS. The three-dimensional model of the aggregate was further optimized. The best fitting cuboid, cylinder, cone and sphere information of the aggregate …

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Effects Of Short-Term Aging On Asphalt Binders And Hot Mix Asphalt At Elevated Temperatures And Extended Aging Time, Rubben Lolly, Waleed Zeiada, Mena Souliman, Kamil Kaloush Jan 2018

Effects Of Short-Term Aging On Asphalt Binders And Hot Mix Asphalt At Elevated Temperatures And Extended Aging Time, Rubben Lolly, Waleed Zeiada, Mena Souliman, Kamil Kaloush

Civil Engineering Faculty Publications and Presentations

The production process of Hot Mix Asphalt (HMA) causes a short term aging (STA) to asphalt binder due to the heating of both asphalt binder and aggregates before mixing together. Laboratory protocols are followed to simulate the STA conditions for both asphalt binders and asphalt mixtures. STA protocols expose asphalt binders or asphalt mixtures to specific aging temperature for a specific period of time to produce stiffening that is similar to that of actual production conditions. Successful construction of HMA in cold season/regions may require elevating the production temperature of HAM to achieve proper compaction of HMA layers. Producing HMA …

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Evaluating The Effectiveness Of Soil-Native Bacteria In Precipitating Calcite To Stabilize Expansive Soils, Bhaskar C. S. Chittoori, Malcolm Burbank, Md Touhidul Islam Jan 2018

Evaluating The Effectiveness Of Soil-Native Bacteria In Precipitating Calcite To Stabilize Expansive Soils, Bhaskar C. S. Chittoori, Malcolm Burbank, Md Touhidul Islam

Civil Engineering Faculty Publications and Presentations

The use of chemical additives to stabilize expansive soils is a common practice. However, the environmental concerns associated with the greenhouse gas generation during the production of these chemicals have launched engineers in search of sustainable stabilization alternatives. Microbial induced calcite precipitation (MICP) is a bio-cementation technique that could be a potential solution to this problem. Typically, MICP is achieved via bio-augmentation; however, bio-stimulation was argued to be a more realistic alternative due to its field implementation potential. Hence, in this research study, two expansive soils with varying plasticity characteristics were examined to understand the potential of MICP in treating …

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Evaluating The Application Of Microbial Induced Calcite Precipitation Technique To Stabilize Expansive Soils, Bhaskar Chittoori, Sikha Neupane Jan 2018

Evaluating The Application Of Microbial Induced Calcite Precipitation Technique To Stabilize Expansive Soils, Bhaskar Chittoori, Sikha Neupane

Civil Engineering Faculty Publications and Presentations

Expansive soils, also known as swell-shrink soils have been a problem for civil infrastructures including roads and foundations from ancient times. The use of chemical additives such as cement and lime to stabilize expansive soils is a common practice among geotechnical engineers, especially for lightly loaded structures. However, several occurrences of subgrade failures have been observed after stabilizing with chemical additives. Hence, engineers are in search of sustainable stabilization alternatives. Microbial Induced Calcite Precipitation (MICP) is gaining attention as an environmentally friendly soil improvement technique. Several researchers have successfully tested its feasibility in mitigating liquefaction-induced problems in sandy soils. In …

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Effect Of Polypropylene Fiber Reinforcement On The Consolidation, Swell And Shrinkage Behavior Of Lime Blended Expansive Soil, Arif Ali Baig Moghal, Bhaskar C.S. Chittoori, B. Munwar Basha Jan 2018

Effect Of Polypropylene Fiber Reinforcement On The Consolidation, Swell And Shrinkage Behavior Of Lime Blended Expansive Soil, Arif Ali Baig Moghal, Bhaskar C.S. Chittoori, B. Munwar Basha

Civil Engineering Faculty Publications and Presentations

In this article, synthetic fibers in the presence of lime stabilization are proposed as an alternative to overcome the issues related to shrink-swell distress in expansive soils. Two types of synthetic fibers, Fiber Cast® (FC) and Fiber Mesh® (FM), were studied by conducting one dimensional fixed ring Oedometer swell-consolidation and bar linear shrinkage tests. Three dosages (0.2, 0.4 and 0.6% percent by weight of soil) and two lengths of the fibers (6 and 12 mm) were evaluated with and without lime treatments. The results indicated that FC fibers had better swell restricting performance in the absence of lime treatment, while …

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Addressing Clay Mineralogy Effects On Performance Of Chemically Stabilized Expansive Soils Subjected To Seasonal Wetting And Drying, Bhaskar C.S. Chittoori, Anand J. Puppala, Aravind Pedarla Jan 2018

Addressing Clay Mineralogy Effects On Performance Of Chemically Stabilized Expansive Soils Subjected To Seasonal Wetting And Drying, Bhaskar C.S. Chittoori, Anand J. Puppala, Aravind Pedarla

Civil Engineering Faculty Publications and Presentations

Premature failures in chemically stabilized expansive soils cause millions of dollars in maintenance and repair costs. One of the reasons for these failures is the inability of existing stabilization design guidelines to consider the complex interactions between clay minerals and the stabilizers. It is vital to understand these complex interactions, as they are responsible for the strength improvement and swell/shrink reduction in these soils, in turn affecting the overall health of the infrastructure. Hence, this research study examined the longevity of chemically stabilized expansive soils subjected to wetting/drying conditions with a major focus on clay mineralogy. Eight different natural soils …

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Unified Approach To Sustainability, Resiliency And Risk Assessments, Thomas Robbins, Bhaskar Chittoori, Amit Gajurel, Robert Hamilton Jan 2018

Unified Approach To Sustainability, Resiliency And Risk Assessments, Thomas Robbins, Bhaskar Chittoori, Amit Gajurel, Robert Hamilton

Civil Engineering Faculty Publications and Presentations

Generally, researchers consider sustainability and resiliency aspects of infrastructure projects independently, without considering the relationship that exists between them. Unified approaches that combine sustainability, resiliency, and analyze risk are very minimal. This paper proposes a unified approach to assessing sustainability, resiliency, and risk for infrastructure via evaluating the performance of a tailings dam under various earthquake magnitudes. A tailings dam is typically in operation for many years, which means they may have a direct impact on the local environment, society, and economy. Due to the extended life of the dam, the probability of a major event occurring that could negatively …

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Prediction Of Average Annual Surface Temperature For Both Flexible And Rigid Pavements, Karthikeyan Loganathan, Mena I. Souliman Dec 2017

Prediction Of Average Annual Surface Temperature For Both Flexible And Rigid Pavements, Karthikeyan Loganathan, Mena I. Souliman

Civil Engineering Faculty Publications and Presentations

The surface temperature of pavements is a critical attribute during pavement design. Surface temperature must be measured at locations of interest based on time-consuming field tests. The key idea of this study is to develop a temperature profile model to predict the surface temperature of flexible and rigid pavements based on weather parameters. Determination of surface temperature with traditional techniques and sensors are replaced by a newly developed method. The method includes the development of a regression model to predict the average annual surface temperature based on weather parameters such as ambient air temperature, relative humidity, wind speed, and precipitation. …

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Dense-Graded Aggregate Base Gradation Influencing Rutting Model Predictions, Issam I. A. Qamhia, Liang Chern Chow, Debakanta Mishra, Erol Tutumluer Dec 2017

Dense-Graded Aggregate Base Gradation Influencing Rutting Model Predictions, Issam I. A. Qamhia, Liang Chern Chow, Debakanta Mishra, Erol Tutumluer

Civil Engineering Faculty Publications and Presentations

This paper presents findings from an ongoing research study at the University of Illinois focused on developing and calibrating an improved permanent deformation model for unbound aggregate materials through laboratory testing and characterization. The project scope included testing sixteen aggregate materials, commonly used in the state of North Carolina for pavement base courses, in the laboratory through monotonic and repeated load triaxial testing. This paper primarily focuses on quantifying effects of aggregate gradation on permanent deformation behavior. To accomplish this, four materials were tested at both: (1) “source gradations,” i.e. original gradations from quarry, and (2) an “engineered gradation,” i.e., …

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Mechanical And Economical Impacts Of Adding Polymers Into Asphalt Mixtures, Mena Souliman, Waleed Zeiada, Lubinda Walubita Sep 2017

Mechanical And Economical Impacts Of Adding Polymers Into Asphalt Mixtures, Mena Souliman, Waleed Zeiada, Lubinda Walubita

Civil Engineering Faculty Publications and Presentations

Load associated fatigue cracking is one of the major distress types occurring in flexible pavements. Flexural bending beam fatigue laboratory test has been used for several decades and is considered an integral part of the Superpave advanced characterization procedure. One of the most significant solutions to sustain the fatigue life for an asphaltic mixture is to add sustainable materials such as polymers to the asphalt mixture. A laboratory testing program was performed on two gap-graded mixtures: unmodified and polymer-modified asphalt mixtures. Strain controlled fatigue tests were conducted according to the AASHTO T321 procedure. The results from the beam fatigue tests …

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Increasing Probability Of Mass-Mortality During Indian Heatwaves, Mojtaba Sadegh Jun 2017

Increasing Probability Of Mass-Mortality During Indian Heatwaves, Mojtaba Sadegh

Civil Engineering Faculty Publications and Presentations

Rising global temperatures are causing increases in the frequency and severity of extreme climatic events such as floods, droughts, and heatwaves. Here, we analyze changes in summer temperatures, the frequency, severity and duration of heatwaves, and heat-related mortality in India between 1960 and 2009, using data from the India Meteorological Department. Mean temperatures across India have risen by more than 0.5 °C over this period, with statistically significant increases in heatwaves. Using a novel probabilistic model, we further show that the increase in summer mean temperatures in India over this period corresponds to a 146% increase in the probability of …

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Target Reliability Approach To Study The Effect Of Fiber Reinforcement On Ucs Behavior Of Lime Treated Semi-Arid Soil, Arif Ali Baig Moghal, Bhaskar C.S. Chittoori, B. Munwar Basha, Mosleh Ali Al-Shamrani Jun 2017

Target Reliability Approach To Study The Effect Of Fiber Reinforcement On Ucs Behavior Of Lime Treated Semi-Arid Soil, Arif Ali Baig Moghal, Bhaskar C.S. Chittoori, B. Munwar Basha, Mosleh Ali Al-Shamrani

Civil Engineering Faculty Publications and Presentations

This paper evaluates the effectiveness of stabilizing expansive soil with two different types of fibers, Fiber Mesh® (FM) and Fiber Cast® (FC), in conjunction with chemical stabilization. The intention of this study is to evaluate the effect of these fibers and lime in stabilizing expansive soil by improving its UCS behavior. The effect of varying lengths (6 mm and 12 mm) and amounts (0.2, 0.4 and 0.6% dosage by weight of soil) of FC and FM fibers and curing periods (0, 7, 28, 60, 120, 180 and 360 days) on the UCS and on secant modulus of a semi-arid expansive …

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Multivariate Copula Analysis Toolbox (Mvcat): Describing Dependence And Underlying Uncertainty Using A Bayesian Framework, Mojtaba Sadegh, Elisa Ragno, Amir Aghakouchak Jun 2017

Multivariate Copula Analysis Toolbox (Mvcat): Describing Dependence And Underlying Uncertainty Using A Bayesian Framework, Mojtaba Sadegh, Elisa Ragno, Amir Aghakouchak

Civil Engineering Faculty Publications and Presentations

We present a newly developed Multivariate Copula Analysis Toolbox (MvCAT) which includes a wide range of copula families with different levels of complexity. MvCAT employs a Bayesian framework with a residual-based Gaussian likelihood function for inferring copula parameters and estimating the underlying uncertainties. The contribution of this paper is threefold: (a) providing a Bayesian framework to approximate the predictive uncertainties of fitted copulas, (b) introducing a hybrid-evolution Markov Chain Monte Carlo (MCMC) approach designed for numerical estimation of the posterior distribution of copula parameters, and (c) enabling the community to explore a wide range of copulas and evaluate them relative …

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Effects Of Tire Inclination (Turning Traffic) And Dynamic Loading On The Pavement Stress-Strain Responses Using 3-D Finite Element Modeling, Xiaodi Hu, Abu N.M. Faruk, Jun Zhang, Mena I. Souliman, Lubinda F. Walubita Apr 2017

Effects Of Tire Inclination (Turning Traffic) And Dynamic Loading On The Pavement Stress-Strain Responses Using 3-D Finite Element Modeling, Xiaodi Hu, Abu N.M. Faruk, Jun Zhang, Mena I. Souliman, Lubinda F. Walubita

Civil Engineering Faculty Publications and Presentations

In this study, ABAQUS finite element (FE) modeling in three-dimensional (3-D) loading mode was utilized to analytically investigate and quantify the effects of tire inclination and dynamic loading on the stress-strain responses of a pavement structure under varying loading and environmental conditions. The input variables for modeling consisted of actual laboratory and field data obtained from an in-service highway US 59 and included the in-situ pavement structure, material properties (i.e., modulus and shear strength), traffic, and climatic (i.e., temperature) data. Computational modeling and sensitivity analyses were conducted through variation of the following two input variables with a focus on the …

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A Mechanistic-Empirical Impact Analysis Of Different Truck Configurations On A Jointed Plain Concrete Pavement (Jpcp), Lubinda F. Walubita, Tito P. Nyamuhokya, Stefan A. Romanoschi, Xiaodi Hu, Mena I. Souliman Apr 2017

A Mechanistic-Empirical Impact Analysis Of Different Truck Configurations On A Jointed Plain Concrete Pavement (Jpcp), Lubinda F. Walubita, Tito P. Nyamuhokya, Stefan A. Romanoschi, Xiaodi Hu, Mena I. Souliman

Civil Engineering Faculty Publications and Presentations

Until the last decade, the 1993 American Association of State Highway and Transportation Officials (AASHTO) design guide has been traditionally used for the design of flexible and rigid pavements in the USA and some parts of the world. However, because of its inability to meet the new traffic and material challenges, a Mechanistic Empirical Pavement Design Guide (MEPDG) was introduced based on an NCHRP 1-37 A study conducted in 2004. This study used the MEPDG software and associated models to determine, through comparative truck damage analysis, the effects of nine different truck configurations on a 12 inch-jointed plain concrete pavement …

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Optimizing Fiber Parameters Coupled With Chemical Treatment: Promethee Approach, Arif Ali Baig Moghal, Ateekh Ur Rehman, Bhaskar Chittoori Jan 2017

Optimizing Fiber Parameters Coupled With Chemical Treatment: Promethee Approach, Arif Ali Baig Moghal, Ateekh Ur Rehman, Bhaskar Chittoori

Civil Engineering Faculty Publications and Presentations

In order to combat issues related to expansive soils, chemical stabilization augmented with use of synthetic fibers is gaining focus in recent times. However, in most of these applications, the practicing field engineers face difficulty in selecting the right mix of fiber size, fiber dosage and stabilizer content. The decision becomes more typical, as the target is to achieve or enhance multiple geotechnical properties which differ with fiber dosage and stabilizer content based on governing mechanisms. Addressing these issues, in this study an attempt is made to present an approach for selecting fibre dosage and lime mix for a typical …

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Concrete Pavement Service Condition Assessment Using Infrared Thermography, Yang Lu, Aidin J. Golrokh, M.D. Aminul Islam Jan 2017

Concrete Pavement Service Condition Assessment Using Infrared Thermography, Yang Lu, Aidin J. Golrokh, M.D. Aminul Islam

Civil Engineering Faculty Publications and Presentations

Infrared thermography (IRT), an effective nondestructive testing method, is used to obtain an initial evaluation of the concrete pavement surface and near surface in a time effective manner. In this paper, the effect of the depth of delamination inside concrete pavement on infrared thermography technique is studied for bridge decks inspection. To be able to mimic the delamination in subsurface, two Styrofoam cubes have been inserted in different depth near the surface of the concrete cylinder. After heating up the specimen, thermal images were taken from the surface using an infrared thermal camera to evaluate the effect of subsurface defects …

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