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Impact Of Curling, Warping, And Other Early-Age Behavior On Concrete Pavement Smoothness: Early, Frequent, And Detailed (Efd) Study, Halil Ceylan, Sunghwan Kim, Dennis J. Turner, Robert Otto Rasmussen, George K. Chang, James Grove, Kasthurirangan Gopalakrishnan 2017 Iowa State University

Impact Of Curling, Warping, And Other Early-Age Behavior On Concrete Pavement Smoothness: Early, Frequent, And Detailed (Efd) Study, Halil Ceylan, Sunghwan Kim, Dennis J. Turner, Robert Otto Rasmussen, George K. Chang, James Grove, Kasthurirangan Gopalakrishnan

Halil Ceylan

This report summarizes the activities in Phase II of “Assessing the Impact to Concrete Pavement Smoothness from Curling, Warping, and other Early-Age Behavior: Early, Frequent, and Detailed (Project 16).” The purpose of this project is to obtain detailed information about factors affecting pavement smoothness during the critical time immediately following construction by conducting a controlled field evaluation of three concrete pavement construction projects. In Phase II, both field and laboratory testing of the materials and construction process were conducted for two newly constructed Jointed Plain Concrete Pavement (JPCP) test sections; one on highway U.S. 34 near Burlington and the ...


Rehabilitation Of Concrete Pavements Utilizing Rubblization And Crack And Seat Methods, Halil Ceylan, Brian J. Coree, Kasthurirangan Gopalakrishnan, Reshma Mathews, Tejeswi Kota 2017 Iowa State University

Rehabilitation Of Concrete Pavements Utilizing Rubblization And Crack And Seat Methods, Halil Ceylan, Brian J. Coree, Kasthurirangan Gopalakrishnan, Reshma Mathews, Tejeswi Kota

Halil Ceylan

Deterioration in portland cement concrete (PCC) pavements can occur due to distresses caused by a combination of traffic loads and weather conditions. Hot mix asphalt (HMA) overlay is the most commonly used rehabilitation technique for such deteriorated PCC pavements.However, the performance of these HMA overlaid pavements is hindered due to the occurrence of reflective cracking, resulting in significant reduction of pavement serviceability. Various fractured slab techniques, including rubblization, crack and seat, and break and seat are used to minimize reflective cracking by reducing the slab action.

However, the design of structural overlay thickness for cracked and seated and rubblized ...


Rehabilitation Of Concrete Pavements Utilizing Rubblization And Crack And Seat Methods (Phase Ii): Performance Evaluation Of Rubblized Pavements In Iowa, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim 2017 Iowa State University

Rehabilitation Of Concrete Pavements Utilizing Rubblization And Crack And Seat Methods (Phase Ii): Performance Evaluation Of Rubblized Pavements In Iowa, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim

Halil Ceylan

This Phase II follow-up study of IHRB Project TR-473 focused on the performance evaluation of rubblized pavements in Iowa. The primary objective of this study was to evaluate the structural condition of existing rubblized concrete pavements across Iowa through Falling Weight Deflectometer (FWD) tests, Dynamic Cone Penetrometer (DCP) tests, visual pavement distress surveys, etc. Through backcalculation of FWD deflection data using the ISU’s advanced layer moduli backcalculation program, the rubblized layer moduli were determined for various projects and compared with each other for correlating with the long-term pavement performance. The AASHTO structural layer coefficient for rubblized layer was also ...


Sensitivity Evaluation Of Mepdg Performance Prediction, Charles W. Schwartz, Rui Li, Sunghwan Kim, Halil Ceylan, Kasthurirangan Gopalakrishnan 2017 University of Maryland - College Park

Sensitivity Evaluation Of Mepdg Performance Prediction, Charles W. Schwartz, Rui Li, Sunghwan Kim, Halil Ceylan, Kasthurirangan Gopalakrishnan

Halil Ceylan

This report documents and presents the results of a study to evaluate the sensitivity of pavement performance predicted by the Mechanistic-Empirical Pavement Design Guide to the values of the design inputs. Global sensitivity analyses were performed for five pavement types under five climate conditions and three traffic levels. Design inputs evaluated in the analyses included traffic volume, layer thicknesses, material properties (e.g., stiffness, strength, HMA and PCC mixture characteristics, subgrade type), groundwater depth, geometric parameters (e.g., lane width), and others. Detailed traffic inputs were not considered. Depending on the base case, approximately 25 to 35 design inputs were ...


Impact Of Curling And Warping On Concrete Pavement, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim, Peter Taylor, Ahmad Abdulraheem Alhasan, Shuo Yang 2017 Iowa State University

Impact Of Curling And Warping On Concrete Pavement, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim, Peter Taylor, Ahmad Abdulraheem Alhasan, Shuo Yang

Halil Ceylan

Portland cement concrete (PCC) pavement undergoes repeated environmental load-related deflection resulting from temperature and moisture variations across the pavement depth. This phenomenon, referred to as PCC pavement curling and warping, has been known and studied since the mid-1920s. Slab curvature can be further magnified under repeated traffic loads and may ultimately lead to fatigue failures, including top-down and bottom-up transverse, longitudinal, and corner cracking. It is therefore important to measure the “true” degree of curling and warping in PCC pavements, not only for quality control (QC) and quality assurance (QA) purposes, but also to achieve a better understanding of its ...


Adaptive Neuro-Fuzzy Inference System-Based Backcalculation Approach To Airport Pavement Structural Analysis, Kasthurirangan Gopalakrishnan, Halil Ceylan 2017 Iowa State University

Adaptive Neuro-Fuzzy Inference System-Based Backcalculation Approach To Airport Pavement Structural Analysis, Kasthurirangan Gopalakrishnan, Halil Ceylan

Halil Ceylan

This paper describes the application of adaptive neuro-fuzzy inference system (ANFIS) methodology for the backcalculation of airport flexible pavement layer moduli. The proposed ANFIS-based backcalculation approach employs a hybrid learning procedure to construct a non-linear input-output mapping based on qualitative aspects of human knowledge and pavement engineering experience incorporated in the form of fuzzy if-then rules as well as synthetically generated Finite Element (FE) based pavement modeling solutions in the form of input-output data pairs. The developed neuro-fuzzy backcalculation methodology was evaluated using hypothetical data as well as extensive non-destructive field deflection data acquired from a state-of-the-art full-scale airport pavement ...


A Predictive Model For Uniaxial Compressive Strength Of Carbonate Rocks From Schmidt Hardness, Murat Yurdakul, Halil Ceylan, Hurriyet Akdas 2017 Iowa State University

A Predictive Model For Uniaxial Compressive Strength Of Carbonate Rocks From Schmidt Hardness, Murat Yurdakul, Halil Ceylan, Hurriyet Akdas

Halil Ceylan

Uniaxial compressive strength (UCS) is considered to be one of the important parameters in rock engineering projects. In order to determine UCS, direct and indirect techniques are employed. In the direct approach, UCS is determined from the laboratory UCS test. In indirect techniques determine UCS based on the nondestructive test findings which can be easily and quickly performed and require relatively simple or no sample preparation. Indirect techniques are commonly preferred by rock and mining engineers because of their low cost and ease. This study presents the findings of an Artificial Neural Networks (ANN) based model for the prediction of ...


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 ...


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 ...


Concrete Pavement Mixture Design And Analysis (Mda): Application Of A Portable X-Ray Fluorescence Technique To Assess Concrete Mix Proportions, Peter Taylor, Ezgi Yurdakul, Halil Ceylan 2017 Iowa State University

Concrete Pavement Mixture Design And Analysis (Mda): Application Of A Portable X-Ray Fluorescence Technique To Assess Concrete Mix Proportions, Peter Taylor, Ezgi Yurdakul, Halil Ceylan

Halil Ceylan

Any transportation infrastructure system is inherently concerned with durability and performance issues. The proportioning and uniformity control of concrete mixtures are critical factors that directly affect the longevity and performance of the portland cement concrete pavement systems. At present, the only means available to monitor mix proportions of any given batch are to track batch tickets created at the batch plant. However, this does not take into account potential errors in loading materials into storage silos, calibration errors, and addition of water after dispatch. Therefore, there is a need for a rapid, cost-effective, and reliable field test that estimates the ...


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 ...


Biofuel Co-Product Uses For Pavement Geo-Materials Stabilization, Kasthurirangan Gopalakrishnan, Halil Ceylan, Sunghwan Kim 2017 Iowa State University

Biofuel Co-Product Uses For Pavement Geo-Materials Stabilization, Kasthurirangan Gopalakrishnan, Halil Ceylan, Sunghwan Kim

Halil Ceylan

The production and use of biofuels has increased in the present context of sustainable development. Biofuel production from plant biomass produces not only biofuel or ethanol but also co-products containing lignin, modified lignin, and lignin derivatives. This research investigated the utilization of lignin-containing biofuel co-products (BCPs) in pavement soil stabilization as a new application area. Laboratory tests were conducted to evaluate the performance and the moisture susceptibility of two types of BCP-treated soil samples compared to the performance of untreated and traditional stabilizer-treated (fly ash) soil samples. The two types of BCPs investigated were (1) a liquid type with higher ...


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 ...


Application Of Shuffled Complex Evolution Optimization Approach To Concrete Pavement Backanalysis, Kasthurirangan Gopalakrishnan, Halil Ceylan 2017 Iowa State University

Application Of Shuffled Complex Evolution Optimization Approach To Concrete Pavement Backanalysis, Kasthurirangan Gopalakrishnan, Halil Ceylan

Halil Ceylan

This paper focuses on the development of a new backcalculation method for concrete pavements 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. Shuffled Complex Evolution (SCE), a type of evolutionary optimization algorithms based on the tradeoff of exploration and exploitation, has been ...


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 ...


Characterization Of Asphalt Materials Using X-Ray High-Resolution Computed Tomography Imaging Techniques, Kasthurirangan Gopalakrishnan, Halil Ceylan, Feyzi Inanc, Joseph Gray, Michael Alan Heitzman 2017 Iowa State University

Characterization Of Asphalt Materials Using X-Ray High-Resolution Computed Tomography Imaging Techniques, Kasthurirangan Gopalakrishnan, Halil Ceylan, Feyzi Inanc, Joseph Gray, Michael Alan Heitzman

Halil Ceylan

X-ray Computerized Tomography (CT) has emerged as a powerful, nondestructive tool to study and quantify the three-dimensional internal structure of HMA. Studies, in conjunction with modeling and computational techniques, have focused on characterization of HMA internal air-void distribution, internal structure evolution during laboratory compaction, damage evolution in specimens during laboratory tests, segregation analysis, forensic investigation of pavements using cores, and the quantification of HMA microstructural properties. The Center for Nondestructive Evaluation (CNDE) at Iowa State University (ISU) has an in-house built high-resolution CT system with customized software for data acquisition, volumetric file reconstruction, and visualization. Preliminary studies were conducted at ...


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 ...


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 ...


Biofuel Co-Product Uses For Pavement Geomaterials Stabilization, Kasthurirangan Gopalakrishnan, Halil Ceylan, Sunghwan Kim 2017 Iowa State University

Biofuel Co-Product Uses For Pavement Geomaterials Stabilization, Kasthurirangan Gopalakrishnan, Halil Ceylan, Sunghwan Kim

Halil Ceylan

Using biomass as a sustainable, renewable energy source can be part of a solution for reducing dependence on fossil fuel–based energy and mitigating global warming, and both the production and use of biofuels made from biomass have increased. Biofuel production creates not only biofuel or ethanol, but also co-products containing lignin, modified lignin, and lignin derivatives. The use of these co-products to help stabilize pavement soils and other geo-materials has been studied over the past decades. However, most lignin-related soil stabilization studies have investigated sulfite lignins (lignosulfonates) derived from the paper industry, while the lignins obtained from biofuel or ...


Identification Of Practices, Design, Construction, And Repair Using Trenchless Technology, Muhannad Suleiman, Larry J. Stevens, Charles T. Jahren, Halil Ceylan, William M. Conway 2017 Iowa State University

Identification Of Practices, Design, Construction, And Repair Using Trenchless Technology, Muhannad Suleiman, Larry J. Stevens, Charles T. Jahren, Halil Ceylan, William M. Conway

Halil Ceylan

Trenchless technologies are methods used for the construction and rehabilitation of underground utility pipes. These methods are growing increasingly popular due to their versatility and their potential to lower project costs. However, the use of trenchless technologies in Iowa and their effects on surrounding soil and nearby structures has not been adequately documented. Surveys of and interviews with professionals working in trenchless-related industries in Iowa were conducted, and the results were analyzed and compared to survey results from the United States as a whole. The surveys focused on method familiarity, pavement distress observed, reliability of trenchless methods, and future improvements ...


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