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Computationally Efficient Surrogate Response Models For Mechanistic-Empirical Pavement Analysis And Design, Halil Ceylan, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Computationally Efficient Surrogate Response Models For Mechanistic-Empirical Pavement Analysis And Design, Halil Ceylan, Kasthurirangan Gopalakrishnan

Halil Ceylan

This paper proposes the use of neural network- (NN-) based pavement structural analysis tools as surrogates for the flexible pavement response analysis in the new mechanistic empirical pavement design guide (MEPDG) developed for the American State Highway and Transportation Officials (AASHTO). Some of the recent successful applications of NN-based structural analysis models for predicting critical flexible pavement responses and nonlinear pavement layer moduli from falling weight deflectometer (FWD) deflection basins are highlighted. Because NNs excel at mapping in higher-order spaces, such models can go beyond the existing univariate relationships between pavement structural responses and performance (such as the subgrade strain ...


Calibration Of Pavement Me Design And Mechanistic-Empirical Pavement Design Guide Performance Prediction Models For Iowa Pavement Systems, Sunghwan Kim, Halil Ceylan, Di Ma, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Calibration Of Pavement Me Design And Mechanistic-Empirical Pavement Design Guide Performance Prediction Models For Iowa Pavement Systems, Sunghwan Kim, Halil Ceylan, Di Ma, Kasthurirangan Gopalakrishnan

Halil Ceylan

The AASHTO Mechanistic-Empirical Pavement Design Guide (MEPDG) pavement performance models and the associated AASHTOWare® Pavement ME Design software are nationally calibrated using design inputs and distress data largely from the national Long-Term Pavement Performance (LTPP). Further calibration and validation studies are necessary for local highway agencies’ implementation by taking into account local materials, traffic information, and environmental conditions. This study aims to improve the accuracy of MEPDG/Pavement ME Design pavement performance predictions for Iowa pavement systems through local calibration of MEPDG prediction models. A total of 70 sites from Iowa representing both jointed plain concrete pavements (JPCPs) and Hot ...


Dynamic Characterization Of A Soft Elastomeric Capacitor For Structural Health Monitoring, Simon Laflamme, Filippo Ubertini, Hussam Saleem, Antonella D'Alessandro, Austin R.J. Downey, Halil Ceylan, Annibale L. Materazzi 2017 Iowa State University

Dynamic Characterization Of A Soft Elastomeric Capacitor For Structural Health Monitoring, Simon Laflamme, Filippo Ubertini, Hussam Saleem, Antonella D'Alessandro, Austin R.J. Downey, Halil Ceylan, Annibale L. Materazzi

Halil Ceylan

Structural health monitoring of civil infrastructures is a difficult task, often impeded by the geometrical size of the monitored systems. Recent advances in conducting polymers enabled the fabrication of flexible sensors capable of covering large areas, a possible solution to the monitoring challenge of mesoscale systems. The authors have previously proposed a novel sensor consisting of a soft elastomeric capacitor (SEC) acting as a strain gauge. Arranged in a network configuration, the SECs have the potential to cover very large surfaces. In this paper, understanding of the proposed sensor is furthered by evaluating its performance at vibration-based monitoring of large-scale ...


Advanced Approaches To Hot-Mix Asphalt Dynamic Modulus Prediction, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim 2017 Iowa State University

Advanced Approaches To Hot-Mix Asphalt Dynamic Modulus Prediction, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim

Halil Ceylan

The dynamic modulus (|E*|) is one of the primary hot-mix asphalt (HMA) material property inputs at all three hierarchical levels in the new Mechanistic-empirical pavement design guide (MEPDG). The existing |E*| prediction models were developed mainly from regression analysis of an |E*| database obtained from laboratory testing over many years and, in general, lack the necessary accuracy for making reliable predictions. This paper describes the development of a simplified HMA |E*| prediction model employing artificial neural network (ANN) methodology. The intelligent |E*| prediction models were developed using the latest comprehensive |E*| database that is available to researchers (from National Cooperative ...


Advanced Approaches To Characterizing Nonlinear Pavement System Responses, Halil Ceylan, Kasthurirangan Gopalakrishnan, Alper Guclu 2017 Iowa State University

Advanced Approaches To Characterizing Nonlinear Pavement System Responses, Halil Ceylan, Kasthurirangan Gopalakrishnan, Alper Guclu

Halil Ceylan

The use of falling weight deflectometer—based backcalculation techniques to determine pavement layer moduli is a cost-effective and widely used method for the structural evaluation of an existing pavement. The nonlinear stress-sensitive response of pavement geomaterials has been well established, and mechanistic-based pavement design can be improved by inclusion of these nonlinear material properties. To further the science of nonlinear backcalculation, the TRB Strength and Deformation Characteristics of Pavement Sections Committee has assembled four data sets that can be used to demonstrate the ability to derive stress-dependent moduli for pavement layers. In this study, validated artificial neural network (ANN)—based ...


A Simplified Approach For Predicting Early-Age Concrete Pavement Deformation, Sunghwan Kim, Kasthurirangan Gopalakrishnan, Halil Ceylan 2017 Iowa State University

A Simplified Approach For Predicting Early-Age Concrete Pavement Deformation, Sunghwan Kim, Kasthurirangan Gopalakrishnan, Halil Ceylan

Halil Ceylan

Studies on deformation characteristics of early-age Jointed Plain Concrete Pavements (JPCP) due to environmental effects have drawn significant interest over the years. However, the complex nature of the problem arising from interacting environmental factors has resulted in difficulties in predicting the JPCP deformation characteristics. This study introduces a simplified approach for predicting the early-age deformation of JPCP due to environmental factors using an equivalent temperature difference concept. A newly constructed JPCP section on highway US-30 near Marshalltown, Iowa was instrumented to monitor the pavement response to variations in temperature and moisture during the first seven days after construction. Based on ...


Hot Mix Asphalt Dynamic Modulus Prediction Using Kernel Machines, Kasthurirangan Gopalakrishnan, Sunghwan Kim, Halil Ceylan 2017 Iowa State University

Hot Mix Asphalt Dynamic Modulus Prediction Using Kernel Machines, Kasthurirangan Gopalakrishnan, Sunghwan Kim, Halil Ceylan

Halil Ceylan

This paper explores the feasibility of applying support vector regression (SVR) kernel-based supervised learning method to develop hot mix asphalt (HMA) dynamic modulus (|E*|) predictive models. SVR-based prediction models were developed using the latest comprehensive |E*| database that is available to the researchers. The SVR model predictions were compared with the existing regression-based prediction model which is employed in the Mechanistic-Empirical Pavement Design Guide (MEPDG). The SVR based |E*| models show better prediction accuracy compared to the existing regression models. The determination of optimal function and parameters for SVR algorithm is recommended to improve the prediction performance of SVR based ...


Impact Of Farm Equipment Loading On Rigid Pavement Performance Using Finite Element Analysis, Shiyun Wang, Halil Ceylan, Sunghwan Kim, Kasthurirangan Gopalakrishnan, Lev Khazanovich, Shongtao Dai 2017 Iowa State University

Impact Of Farm Equipment Loading On Rigid Pavement Performance Using Finite Element Analysis, Shiyun Wang, Halil Ceylan, Sunghwan Kim, Kasthurirangan Gopalakrishnan, Lev Khazanovich, Shongtao Dai

Halil Ceylan

The increase in agricultural product sales in recent years has led to the use of larger hauling and application equipment to transfer farm productions. This rapid shift in equipment size has raised a concern about their potential to cause significant damage in pavements and bridges. The study reported in this paper (part of a larger pooled fund study initiated in 2007) discusses the impact of farm equipment loading on rigid pavement performance based on Finite Element (FE) analysis. The study considered various types of farm equipment to determine the pavement responses and to quantify their damage on rigid pavement systems ...


I-Back: Iowa's Intelligent Pavement Backcalculation Software, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim 2017 Iowa State University

I-Back: Iowa's Intelligent Pavement Backcalculation Software, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim

Halil Ceylan

The Iowa Department of Transportation (DOT) has been collecting falling weight deflectometer (FWD) data on a regular basis. However, the pavement layer moduli backcalculation techniques used so far have been cumbersome and time consuming. More efficient and faster methods in FWD test data analysis were demanded and deemed necessary for routine analysis. Researchers at Iowa State University (ISU) have developed a suite of advanced pavement layer moduli backcalculation models using the artificial neural networks (ANN) methodology for flexible, rigid, and composite pavements. The current study aims to develop a fully automated backcalculation software system, referred to as I-BACK, with improved ...


Hot Mix Asphalt Dynamic Modulus Prediction Models Using Neural Networks Approach, Halil Ceylan, Sunghwan Kim, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Hot Mix Asphalt Dynamic Modulus Prediction Models Using Neural Networks Approach, Halil Ceylan, Sunghwan Kim, Kasthurirangan Gopalakrishnan

Halil Ceylan

The primary objective of this study is to develop a simplified Hot Mix Asphalt (HMA) dynamic modulus (|E*|) prediction model with fewer input variables compared to the existing regression based models without compromising prediction accuracy. ANN-based prediction models were developed using the latest comprehensive |E*| database that is available to the researchers containing 7,400 data points from 346 HMA mixtures. The ANN model predictions were compared with the existing regression-based prediction models which are included in the latest Mechanistic-Empirical Pavement Design Guide (MEPDG). The ANN based |E*| models show significantly higher prediction accuracy compared to the existing regression models ...


Simulation Of Early-Age Jointed Plain Concrete Pavement Deformation Under Environmental Loading Using The Finite Element Method, Sunghwan Kim, Halil Ceylan, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Simulation Of Early-Age Jointed Plain Concrete Pavement Deformation Under Environmental Loading Using The Finite Element Method, Sunghwan Kim, Halil Ceylan, Kasthurirangan Gopalakrishnan

Halil Ceylan

The objective of this study was to quantify the early-age Portland Cement Concrete (PCC) slab deformations due to pure environmental loading at critical periods immediately following construction. A newly constructed Jointed Plain Concrete Pavement (JPCP) section on highway US-30 near Marshalltown, Iowa, USA was instrumented to monitor the pavement response to variations in temperature and moisture during the first seven days after construction in the summer of 2005. Temperature and humidity sensors installed within the test sections monitored the variations in temperature and moisture. The PCC slab deformations were measured using the Linear Variable Differential Transducers (LVDTs) installed at corner ...


Preliminary Investigation On Determining The Minimum Cement Content In Rigid Pavements, Ezgi Yurdakul, Peter Taylor, Halil Ceylan, Fatih Bektas 2017 Iowa State University

Preliminary Investigation On Determining The Minimum Cement Content In Rigid Pavements, Ezgi Yurdakul, Peter Taylor, Halil Ceylan, Fatih Bektas

Halil Ceylan

This paper presents the preliminary results of an experimental program that consists of testing of concrete mixtures with varying water-to-binder ratios (w/b) and cementitious contents. The purpose of this laboratory study is to investigate the minimum cement content that can be used in rigid pavements without sacrificing the performance (i.e., strength and durability). Initially, 16 mixes using only portland cement and 48 mixes incorporating supplementary cementitious materials, namely class F fly ash, class C fly ash and slag as portland cement replacement at levels of 20%, 20% and 40%, respectively, were planned. This paper reports the results of ...


Local Calibration Studies On Darwin-Me/Mechanistic-Empirical Pavement Design Guide Jointed Plain Concrete Pavement Performance Prediction Models, Sunghwan Kim, Halil Ceylan, Di Ma, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Local Calibration Studies On Darwin-Me/Mechanistic-Empirical Pavement Design Guide Jointed Plain Concrete Pavement Performance Prediction Models, Sunghwan Kim, Halil Ceylan, Di Ma, Kasthurirangan Gopalakrishnan

Halil Ceylan

The AASHTO Mechanistic-Empirical Pavement Design Guide (MEPDG) pavement performance models and the associated AASHTOWare® pavement design software of DARWin-ME are nationally calibrated using design inputs and distress data largely from the national Long-Term Pavement Performance (LTPP). Further calibration and validation studies are necessary for local highway agencies’ implementation by taking into account local materials, traffic information, and environmental conditions. This study aims to improve the accuracy of MEPDG/ DARWin-ME pavement performance predictions for Iowa jointed plain concrete pavements (JPCPs) through local calibration of MEPDG prediction models. The accuracy of the nationally calibrated MEPDG prediction models for Iowa conditions was evaluated ...


Impact Of Bio-Fuel Co-Product Modified Subgrade On Flexible Pavement Performance, Sunghwan Kim, Kasthurirangan Gopalakrishnan, Halil Ceylan 2017 Iowa State University

Impact Of Bio-Fuel Co-Product Modified Subgrade On Flexible Pavement Performance, Sunghwan Kim, Kasthurirangan Gopalakrishnan, Halil Ceylan

Halil Ceylan

This study explored the feasibility of lignin based biofuel co-product (BCP) for subgrade soil stabilization, and more specifically, its impact on Hot-Mix Asphalt (HMA) pavement performance using the Mechanistic-Empirical Pavement Design Guide (MEPDG). The HMA pavement systems with BCP stabilized subgrade under different traffic and climate conditions were modeled using mechanistic based damage analysis system. The performances of BCP stabilized subgrade and natural soil subgrade sections were compared in terms of fatigue (alligator) cracking and rutting predictions on HMA pavements. The results of this study indicate that BCP stabilization of subgrade soil could achieve more sustainable HMA pavements under different ...


Mechanistic-Based Characterization Of Non-Linear Pavement Mechanical Properties With Evolving Intelligent Information Processing Systems, Kasthurirangan Gopalakrishnan, Halil Ceylan, Sunghwan Kim 2017 Iowa State University

Mechanistic-Based Characterization Of Non-Linear Pavement Mechanical Properties With Evolving Intelligent Information Processing Systems, Kasthurirangan Gopalakrishnan, Halil Ceylan, Sunghwan Kim

Halil Ceylan

The backcalculation methodology is an inverse process to determine in-situ materials stiffness of pavement layer from Non-Destructive Test (NDT) surface deflections using iterative optimization or more recently, computational intelligence techniques. Intelligent Information Systems (IIS) have been developed with the idea of dealing with information in a way a human expert would by incorporating abilities to learn fast from a large amount of data, dynamically create new modules, connections and neurons, accommodate imprecise or uncertain knowledge, etc. Evolving Connectionist Systems (ECOS) are IIS created with such requirements in mind. This paper explores the feasibility of applying an ECOS methodology, namely Dynamic ...


Non-Linear Inverse Analysis Of Transportation Structures Using Neuro-Adaptive Networks With Hybrid Learning Algorithm, Kasthurirangan Gopalakrishnan, Siddhartha K. Khaitan, Halil Ceylan 2017 Iowa State University

Non-Linear Inverse Analysis Of Transportation Structures Using Neuro-Adaptive Networks With Hybrid Learning Algorithm, Kasthurirangan Gopalakrishnan, Siddhartha K. Khaitan, Halil Ceylan

Halil Ceylan

The load-bearing capacity of pavement structures is a fundamental structural performance metric of transportation infrastructure networks in the context of safe and efficient movement of people and goods from one place to another. Non-destructive test (NDT) methods are typically employed to routinely evaluate the structural condition of pavement structures, their lifespan and the appropriate maintenance activities to be carried out. This involves computing the Young’s modulus of each layer of the pavement structure through inverse analysis of acquired NDT data. Over the past two decades, soft computing techniques such as Artificial Neural Networks (ANNs), Genetic Algorithms (GAs), and Fuzzy ...


Sustainable Use Of Lignocellulosic Biorefineries Co-Products In Geotechnical Bulk Applications: Comparative Analysis Of Lab Data, Kasthurirangan Gopalakrishnan, Halil Ceylan, Sunghwan Kim 2017 Iowa State University

Sustainable Use Of Lignocellulosic Biorefineries Co-Products In Geotechnical Bulk Applications: Comparative Analysis Of Lab Data, Kasthurirangan Gopalakrishnan, Halil Ceylan, Sunghwan Kim

Halil Ceylan

This paper discusses the effect of two co-products from lignocellulosic biorefineries on a typical Iowa subgrade soil in terms of laboratory measured strength and compaction properties. Emphasis is given to detailed data analysis of laboratory test results in comparing treated soils with untreated soils under different moisture conditions and additive concentrations. Results reveal that the bio-energy co-product (BCP) additives investigated in this study are promising materials to improve strength property of the typical Iowa soil classified to CL or A-6(8) for geotechnical applications. Especially, the co-product A containing higher lignin content is a more effective additive to reduce plastic ...


Smart Airport Pavement Instrumentation And Health Monitoring, Shuo Yang, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim 2017 Iowa State University

Smart Airport Pavement Instrumentation And Health Monitoring, Shuo Yang, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim

Halil Ceylan

Realistic characterization of pavement layer properties and responses under in-situ field conditions is critical for accurate airport pavement life predictions, planning pavement management activities as well as for calibration and validation of mechanistic-based pavement response prediction models. The recent advancements in Micro-Electro-Mechanical Sensor (MEMS)/Nano-Electro-Mechanical Sensor (NEMS) technologies and wireless sensor networks combined with efficient energy scavenging paradigms provide opportunities for long-term, continuous, real-time response measurement and health monitoring of transportation infrastructure systems.

This paper presents a summary review of some recent studies that have focused on the development of advanced smart sensing and monitoring systems for highway pavement system ...


Statistical Model Of Tyre-Road Noise For Thin Layer Surfacing, M. Li, W. van Keulen, Halil Ceylan, M.F.C van de Ven, A.A.A Molenaar 2017 Research Institute of Highway Ministry of Transport

Statistical Model Of Tyre-Road Noise For Thin Layer Surfacing, M. Li, W. Van Keulen, Halil Ceylan, M.F.C Van De Ven, A.A.A Molenaar

Halil Ceylan

Noise produced from the tyre - road surface interface is one of the most important contributions to the overall traffic noise, and there is an increasing requirement for predicting the trye - road noise leaves prior to road construction in the Netherlands. In practice, a model with a simple structure as well as a high accuracy is applicable in road engineering. And material properties are preferred to be used as input variables of the prediction model, which will facilitate the pavement design. Based on these considerations, models are developed for evaluating the tyre - road noise from the asphalt mixture compositions and road ...


Structural Evaluation Of Rubblized Concrete Pavements In Iowa, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim 2017 Iowa State University

Structural Evaluation Of Rubblized Concrete Pavements In Iowa, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim

Halil Ceylan

Rubblization is one of the surface preparation techniques before placing a Hot Mix Asphalt (HMA) overlay that involves breaking the Portland Cement Concrete (PCC) pavement into pieces. This paper describes the structural assessment related to the long term performance of rubblized concrete pavements in Iowa. The structural performance of seven representative in-service rubblized concrete pavement sections across Iowa were evaluated through Falling Weight Deflectometer (FWD) and Dynamic Cone Penetrometer (DCP) tests, and visual pavement distress surveys. Through backcalculation of FWD deflection data using the Iowa State University (ISU) layer moduli backcalculation program, the pavement layer moduli values were determined and ...


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