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Non-Destructive Evaluation Of In-Place Rehabilitated Concrete Pavements, Kasthurirangan Gopalakrishnan, Sunghwan Kim, Halil Ceylan 2017 Iowa State University

Non-Destructive Evaluation Of In-Place Rehabilitated Concrete Pavements, Kasthurirangan Gopalakrishnan, Sunghwan Kim, Halil Ceylan

Halil Ceylan

Several in-place rehabilitation techniques have been used before placing an Asphalt Concrete (AC) overlay on Portland Cement Concrete (PCC) pavements in attempts to minimize reflection cracking. Among these techniques, "rubblization" of PCC has been recognized to be the most utilized procedure for the mitigation of reflection cracking in US. This paper presents the practices on the use of rubblization in US and discusses the performance of this technique based on field evaluation. The specifications for the rubblization procedure used by state Department of Transportation (DOT) in US were reviewed. To evaluate the performance of rubblization technique, the structural and the ...


Knowledge Discovery And Data Mining In Pavement Inverse Analysis, Kasthurirangan Gopalakrishnan, Ankit Agrawal, Halil Ceylan, Sunghwan Kim, Alok Choudhary 2017 Iowa State University

Knowledge Discovery And Data Mining In Pavement Inverse Analysis, Kasthurirangan Gopalakrishnan, Ankit Agrawal, Halil Ceylan, Sunghwan Kim, Alok Choudhary

Halil Ceylan

This paper describes the use of data mining tools for predicting the non-linear layer moduli of asphalt road pavement structures based on the deflection profiles obtained from non-destructive deflection testing. The deflected shape of the pavement under vehicular loading is predominantly a function of the thickness of the pavement layers, the moduli of individual layers, and the magnitude of the load. The process of inverse analysis, more commonly referred to as backcalculation, is used to estimate the elastic (Young's) moduli of individual pavement layers based upon surface deflections. A comprehensive synthetic database of pavement response solutions was generated using ...


Neural Networks Applications In Pavement Engineering: A Recent Survey, Halil Ceylan, Mustafa Birkan Bayrak, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Neural Networks Applications In Pavement Engineering: A Recent Survey, Halil Ceylan, Mustafa Birkan Bayrak, Kasthurirangan Gopalakrishnan

Halil Ceylan

The use of neural networks (NNs) has increased tremendously in several areas of engineering over the last three decades. This paper is intended to provide a state-of-the-art survey of NN applications in pavement engineering over the last three decades. The reported studies are briefly summarized under eight different categories: (1) prediction of pavement condition and performance, (2) pavement management and maintenance strategies, (3) pavement distress forecasting, (4) structural evaluation of pavement systems, (5) pavement image analysis and classification, (6) pavement materials modeling, and (7) other miscellaneous transportation infrastructure applications. To maintain consistency, the review was primarily based on archival journal ...


Initial Smoothness Of Concrete Pavements Under Environmental Loads, S. Kim, Halil Ceylan, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Initial Smoothness Of Concrete Pavements Under Environmental Loads, S. Kim, Halil Ceylan, Kasthurirangan Gopalakrishnan

Halil Ceylan

In the current paper, the effect of curling and warping, caused by environmental ambient conditions, on the initial smoothness of concrete pavements is discussed. Surface profile measurements were made during the hours of the early morning and late afternoon on an instrumented jointed plain concrete pavement (JPCP) on highway US-30 near Marshalltown, Iowa during the first seven days after construction in summer 2005. Variations in temperature and moisture during this critical period were monitored using the temperature and relative humidity sensors installed within the test sections at the time of construction. Based on the measured surface profile data, it was ...


Finite Element Based Hybrid Evolutionary Optimization Approach To Solving Rigid Pavement Inversion Problem, Halil Ceylan, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Finite Element Based Hybrid Evolutionary Optimization Approach To Solving Rigid Pavement Inversion Problem, Halil Ceylan, Kasthurirangan Gopalakrishnan

Halil Ceylan

This paper focuses on the development of a new backcalculation method for concrete road structures based on a hybrid evolutionary global optimization algorithm, namely shuffled complex evolution (SCE). Evolutionary optimization algorithms are ideally suited for intrinsically multi-modal, non-convex, and discontinuous real-world problems such as pavement backcalculation because of their ability to explore very large and complex search spaces and locate the globally optimal solution using a parallel search mechanism as opposed to a point-by-point search mechanism employed by traditional optimization algorithms. SCE, a type of evolutionary optimization algorithms based on the tradeoff of exploration and exploitation, has proved to be ...


Moisture Susceptibility Of Subgrade Soils Stabilized By Lignin-Based Renewable Energy Coproduct, Sunghwan Kim, Kasthurirangan Gopalakrishnan, Halil Ceylan 2017 Iowa State University

Moisture Susceptibility Of Subgrade Soils Stabilized By Lignin-Based Renewable Energy Coproduct, Sunghwan Kim, Kasthurirangan Gopalakrishnan, Halil Ceylan

Halil Ceylan

Sustainable use of biomass as a renewable source of energy can be an alternative solution to the cost of fossil-based energy and global warming. Production of biofuel from plant biomass results not only in bio-based energy, but also in coproducts containing lignin, modified lignin, and lignin derivatives. This paper discusses the moisture susceptibility of subgrade soil stabilized by bio-based energy coproducts containing lignin, with the aim of establishing a new application for bio-based energy coproducts in soil stabilization. An experimental test program was conducted to compare the moisture susceptibility of lignin coproduct-treated soils and traditional fly ash stabilizer-treated soil samples ...


Effect Of M-E Design Guide Inputs On Flexible Pavement Performance Predictions, Sunghwan Kim, Halil Ceylan, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Effect Of M-E Design Guide Inputs On Flexible Pavement Performance Predictions, Sunghwan Kim, Halil Ceylan, Kasthurirangan Gopalakrishnan

Halil Ceylan

In support of the initiatives for implementing the new Mechanistic- Empirical Pavement Design Guide (MEPDG) in Iowa, a preliminary sensitivity study was undertaken to assess the comparative effect of design input parameters pertaining to material properties, traffic and climate on performance of two existing flexible pavements in Iowa with relatively thick Asphalt Concrete (AC) layers. A total of 20 individual inputs were evaluated by studying the effect of each input on five different performance measures (longitudinal cracking, alligator cracking, transverse cracking, rutting, and roughness) for each pavement structure resulting in about 200 simulations using the MEPDG software. The results showed ...


Global Sensitivity Analysis Of Jointed Plain Concrete Pavement Mechanistic-Empirical Performance Predictions, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim, Charles W. Schwartz, Rui Li 2017 Iowa State University

Global Sensitivity Analysis Of Jointed Plain Concrete Pavement Mechanistic-Empirical Performance Predictions, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim, Charles W. Schwartz, Rui Li

Halil Ceylan

The new AASHTO Mechanistic-Empirical Pavement Design Guide (MEPDG) provides pavement analysis and performance predictions for various what-if scenarios. MEPDG performance predictions for anticipated climatic and traffic conditions will depend on the values of the input parameters that characterize pavement materials, layers, design features, and condition. A comprehensive global sensitivity analysis methodology is proposed for evaluating performance predictions for jointed plain concrete pavement to MEPDG inputs for five climatic conditions and three traffic levels. MEPDG inputs evaluated in the analysis include traffic volume, layer thicknesses, material properties, groundwater depth, and geometric parameters. Correlations between MEPDG inputs were considered as appropriate. The ...


Global Sensitivity Analysis Of Mechanistic–Empirical Performance Predictions For Flexible Pavements, Charles W. Schwartz, Rui Li, Halil Ceylan, Sunghwan Kim, Kasthurirangan Gopalakrishnan 2017 University of Maryland - College Park

Global Sensitivity Analysis Of Mechanistic–Empirical Performance Predictions For Flexible Pavements, Charles W. Schwartz, Rui Li, Halil Ceylan, Sunghwan Kim, Kasthurirangan Gopalakrishnan

Halil Ceylan

The new AASHTO Mechanistic–Empirical Pavement Design Guide (MEPDG) provides pavement analysis and performance predictions for various feasible design scenarios. The MEPDG performance predictions for the anticipated climatic and traffic conditions depends on the values of the input parameters that characterize the pavement materials, layers, design features, and condition. This paper focuses on comprehensive global sensitivity analyses of flexible pavement performance predictions to MEPDG design inputs under five climatic conditions and three traffic levels. Design inputs evaluated in the analyses include traffic volume, layer thicknesses, material properties, and groundwater depth. Correlations between design inputs were considered as appropriate. The global ...


Development Of A Neural Network Simulator For Studying The Constitutive Behavior Of Structural Composite Materials, Hyuntae Na, Seung-Yub Lee, Ersan Ustundag, Sarah L. Ross, Halil Ceylan, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Development Of A Neural Network Simulator For Studying The Constitutive Behavior Of Structural Composite Materials, Hyuntae Na, Seung-Yub Lee, Ersan Ustundag, Sarah L. Ross, Halil Ceylan, Kasthurirangan Gopalakrishnan

Halil Ceylan

This paper introduces a recent development and application of a noncommercial artificial neural network (ANN) simulator with graphical user interface (GUI) to assist in rapid data modeling and analysis in the engineering diffraction field. The real-time network training/simulation monitoring tool has been customized for the study of constitutive behavior of engineering materials, and it has improved data mining and forecasting capabilities of neural networks. This software has been used to train and simulate the finite element modeling (FEM) data for a fiber composite system, both forward and inverse. The forward neural network simulation precisely reduplicates FEM results several orders ...


Evaluation Of The Mechanistic-Empirical Pavement Design Guide For Implementation In Iowa, Halil Ceylan, Brian Coree, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Evaluation Of The Mechanistic-Empirical Pavement Design Guide For Implementation In Iowa, Halil Ceylan, Brian Coree, Kasthurirangan Gopalakrishnan

Halil Ceylan

With the release of the new Mechanistic-Empirical Pavement Design Guide (MEPDG) in the USA, there is a big shift in pavement analysis and design and many state highway agencies are undertaking initiatives to implement the MEPDG. The Iowa Department of Transportation (DOT) is one such highway agency in the USA interested in implementing the MEPDG. In order to effectively and efficiently transition to the MEPDG from the current empirical approach and accelerate its adoption, the Iowa DOT needs a detailed implementation and training strategy. In support of the MEPDG implementation initiatives, sensitivity studies were conducted using the MEPDG software to ...


Effect Of Water-To-Binder Ratio, Air Content, And Type Of Cementitious Materials On Fresh And Hardened Properties Of Binary And Ternary Blended Concrete, Ezgi Yurdakul, Peter C. Taylor, Halil Ceylan, Fatih Bektas 2017 Iowa State University

Effect Of Water-To-Binder Ratio, Air Content, And Type Of Cementitious Materials On Fresh And Hardened Properties Of Binary And Ternary Blended Concrete, Ezgi Yurdakul, Peter C. Taylor, Halil Ceylan, Fatih Bektas

Halil Ceylan

The purpose of this study is to investigate the effects of water-to-binder ratio (w/b), air content, and type of cementitious material on the fresh and hardened properties of binary and ternary blended concrete mixtures in pavements. This experimental program prepared a total matrix of 54 mixtures with w/b of 0.40 and 0.45; nominal air content of 2, 4, and 8%; and three types of supplementary cementitious materials and one ordinary portland cement in different combinations. Binder systems included ordinary portland cement, binary mixtures with slag cement, Classes F and C fly ash, and ternary mixtures containing ...


Airfield Pavement Deterioration Assessment Using Stress-Dependent Neural Network Models, Kasthurirangan Gopalakrishnan, Halil Ceylan, Alper Guclu 2017 Iowa State University

Airfield Pavement Deterioration Assessment Using Stress-Dependent Neural Network Models, Kasthurirangan Gopalakrishnan, Halil Ceylan, Alper Guclu

Halil Ceylan

In this study, an artificial neural network (ANN)-based approach was employed to backcalculate the asphalt concrete and non-linear stress-dependent subgrade moduli from non-destructive test (NDT) data acquired at the Federal Aviation Administration's National Airport Pavement Test Facility (NAPTF) during full-scale traffic testing. The ANN models were trained with results from an axisymmetric finite element pavement structural model. Using the ANN-predicted moduli based on the NDT test results, the relative severity effects of simulated Boeing 777 (B777) and Boeing 747 (B747) aircraft gear trafficking on the structural deterioration of NAPTF flexible pavement test sections were characterized. The results indicate ...


Effect Of Concrete Strength And Stiffness Characterization On Predictions Of Mechanistic–Empirical Performance For Rigid Pavements, Charles W. Schwartz, Rui Li, Sunghwan Kim, Halil Ceylan, Kasthurirangan Gopalakrishnan 2017 University of Maryland - College Park

Effect Of Concrete Strength And Stiffness Characterization On Predictions Of Mechanistic–Empirical Performance For Rigid Pavements, Charles W. Schwartz, Rui Li, Sunghwan Kim, Halil Ceylan, Kasthurirangan Gopalakrishnan

Halil Ceylan

The hierarchical approach for specifying design inputs is a key feature of the new "Mechanistic–Empirical Pavement Design Guide" (MEPDG). The three levels of design input for the strength and stiffness characterization of portland cement concrete (PCC) range from a Level 1 laboratory measurement of modulus of elasticity and modulus of rupture at 7, 14, 28, and 90 days to a Level 3 estimation of the 28-day unconfined compressive strength. This paper evaluates the effect of design input level for PCC strength and stiffness properties on MEPDG performance predictions for jointed plain concrete pavements (JPCPs). The effects of the different ...


Environmental Effects On Deformation And Smoothness Behavior Of Early-Age Jointed Plain Concrete Pavements, Halil Ceylan, Sunghwan Kim, Kasthurirangan Gopalakrishnan, Kejin Wang 2017 Iowa State University

Environmental Effects On Deformation And Smoothness Behavior Of Early-Age Jointed Plain Concrete Pavements, Halil Ceylan, Sunghwan Kim, Kasthurirangan Gopalakrishnan, Kejin Wang

Halil Ceylan

In this paper, a study of environmental effects on the deformation and smoothness behavior of jointed plain concrete pavement (JPCP) during its early age is presented. A newly constructed JPCP on US-34 near Burlington, Iowa, was instrumented and monitored during the critical time immediately following construction to identify its early-age behavior regarding temperature variations. The surface profiles were measured in diurnal cycles. The primary objective of this research was to investigate the effect of the early-age curling and warping behavior on the initial smoothness of newly constructed JPCPs. Variations in temperature during these critical periods were monitored by temperature sensors ...


Design Of Rigid Pavements In Iowa Using The Mechanistic-Empirical Pavement Design Guide, Halil Ceylan, Brian Coree, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Design Of Rigid Pavements In Iowa Using The Mechanistic-Empirical Pavement Design Guide, Halil Ceylan, Brian Coree, Kasthurirangan Gopalakrishnan

Halil Ceylan

The Iowa Dept of Transportation (DOT) currently utilizes the empirically-based American Association of State Highway and Transportation Officials (AASHTO) pavement design procedures originally derived from the 1960 Road Test data. It is clear that these empirical procedures are no longer applicable to current conditions in Iowa. With the release of the new Mechanistic-Empirical Pavement Design Guide (MEPDG) in the USA, there is a big shift in pavement analysis and design and many state highway agencies undertake initiatives to implement the MEPDG. In order to effectively and efficiently transition to the MEPDG and accelerate its adoption, the Iowa DOT needs a ...


Finite Element Modeling Of Environmental Effects On Rigid Pavement Deformation, Sunghwan Kim, Halil Ceylan, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Finite Element Modeling Of Environmental Effects On Rigid Pavement Deformation, Sunghwan Kim, Halil Ceylan, Kasthurirangan Gopalakrishnan

Halil Ceylan

In this study, finite element (FE)-based primary pavement response models are employed for investigating the early-age deformation characteristics of jointed plain concrete pavements (JPCP) under environmental effects. The FE-based ISLAB (two-and-one-half-dimensional) and EverFE (three-dimensional) software were used to conduct the response analysis. Sensitivity analyses of input parameters used in ISLAB and EverFE were conducted based on field and laboratory test data collected from instrumented pavements on highway US-34 near Burlington, Iowa. Based on the combination of input parameters and equivalent temperatures established from preliminary studies, FE analyses were performed and compared with the field measurements. Comparisons between field measured ...


Effect Of Paste-To-Voids Volume Ratio On The Performance Of Concrete Mixtures, Ezgi Yurdakul, Peter C. Taylor, Halil Ceylan, Fatih Bektas 2017 Iowa State University

Effect Of Paste-To-Voids Volume Ratio On The Performance Of Concrete Mixtures, Ezgi Yurdakul, Peter C. Taylor, Halil Ceylan, Fatih Bektas

Halil Ceylan

The purpose of this study is to investigate the minimum paste volume required with an appropriate water-to-cementitious ratio (w/cm) to achieve required workability, strength, and durability requirements of concrete mixtures for pavements. In this experimental program, 64 concrete mixtures with varying w/cm, cementitious content, and binder type were prepared and tested. The fine aggregateto-total aggregate ratio was held constant for all the mixtures. Fresh and hardened concrete properties of the mixtures were determined at various ages. Test results have shown that approximately 1.5 times more paste by volume is required than voids between the aggregates to achieve ...


Early-Age Response Of Concrete Pavements To Temperature And Moisture Variations, Sunghwan Kim, Kasthurirangan Gopalakrishnan, Halil Ceylan, Kejin Wang 2017 Iowa State University

Early-Age Response Of Concrete Pavements To Temperature And Moisture Variations, Sunghwan Kim, Kasthurirangan Gopalakrishnan, Halil Ceylan, Kejin Wang

Halil Ceylan

In this paper, the early-age response of a Jointed Plain Concrete Pavement (JPCP) to temperature and moisture variations at the time of paving and immediately following construction is discussed. A newly constructed JPCP on US-30 near Marshalltown, Iowa, USA was instrumented and monitored during the critical time immediately following construction to identify its early-age behavior with respect to pavement deformation due to temperature and moisture variations. The instrumentation consisted of Linear Variable Differential Transducers (LVDTs) at the slab corner, center, and edges, and thermocouples and humidity sensors installed within the slab depth. The slab deformation associated with temperature and moisture ...


Accuracy Of Predictive Models For Dynamic Modulus Of Hot-Mix Asphalt, Halil Ceylan, Charles W. Schwartz, Sunghwan Kim, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Accuracy Of Predictive Models For Dynamic Modulus Of Hot-Mix Asphalt, Halil Ceylan, Charles W. Schwartz, Sunghwan Kim, Kasthurirangan Gopalakrishnan

Halil Ceylan

Various models have been developed over the past several decades to predict the dynamic modulus /E*/ of hot-mix asphalt (HMA) based on regression analysis of laboratory measurements. The models most widely used in the asphalt community today are the Witczak 1999 and 2006 predictive models. Although the overall predictive accuracies for these existing models as reported by their developers are quite high, the models generally tend to overemphasize the influence of temperature and understate the influence of other mixture characteristics. Model accuracy also tends to fall off at the low and high temperature extremes. Recently, researchers at Iowa State Univ ...


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