Neural Network-Based Backcalculation Models For Non-Destructive Evaluation Of Rigid Airfield Pavement Systems, 2017 Iowa State University
Neural Network-Based Backcalculation Models For Non-Destructive Evaluation Of Rigid Airfield Pavement Systems, M. Birkan Bayrak, Kasthurirangan Gopalakrishnan, Halil Ceylan
Heavy Weight Deflectometer (HWD) tests were routinely conducted on three Portland Cement Concrete (PCC) test items in the Federal Aviation Administration’s (FAA's) National Airport Pavement Test Facility (NAPTF) to verify the uniformity of the test pavement structures and to measure pavement responses during full-scale traffic testing. A six-wheel aircraft landing gear with dual-tridem configuration was trafficked on the north side of the test pavement while the south side was trafficked by a four-wheel landing gear with dual tandem configuration. HWD tests were conducted before and during traffic testing at slab center, at longitudinal joints and at transverse joints ...
Neural Networks Based Models For Mechanistic-Empirical Design Of Rubblized Concrete Pavements, 2017 Iowa State University
Neural Networks Based Models For Mechanistic-Empirical Design Of Rubblized Concrete Pavements, Halil Ceylan, Kasthurirangan Gopalakrishnan
Rubblization is an in-place rehabilitation technique that involves breaking the concrete pavement into pieces. This process results in a structurally sound, rut resistant base layer which prevents reflective cracking (by obliterating the existing concrete pavement distresses and joints) that can then be overlaid with Hot-Mix Asphalt (HMA). The design of the structural overlay thickness for rubblized projects is difficult as the resulting structure is neither a true rigid pavement nor a true flexible pavement. The HMA overlay thickness design methodology currently used in the state of Iowa is purely empirical. In the Mechanistic-Empirical (M-E) design approach developed for the analysis ...
Performance Engineered Mixtures For Concrete Pavements In The Us, 2017 Iowa State University
Performance Engineered Mixtures For Concrete Pavements In The Us, Peter C. Taylor, Ezgi Yurdakul, Halil Ceylan
Many concrete pavement mixtures in the US are proportioned based on recipes that have been used before, or on prescriptive specifications. As budgets grow tighter and increasing attention is being paid to sustainability metrics, greater attention is beginning to be focused on making mixtures that are more efficient in their usage of materials, yet do not compromise engineering performance. While the technology is largely available in the concrete industry, a number of challenges are slowing the development of more performance-based specifications and mixtures in the US market. These include resistance to change from familiar to less known, resistance to any ...
Rigid Pavement Backcalculation Using Differential Evolution, 2017 Iowa State University
Rigid Pavement Backcalculation Using Differential Evolution, Kasthurirangan Gopalakrishnan, Halil Ceylan
The backcalculation of pavement layer moduli from Falling Weight Deflectometer (FWD) measured surface deflections is a challenging task. It can also be formulated as a global optimization problem with the objective of finding the optimal pavement layer moduli values that minimize the error between measured and computed surface deflections. Over the years, several backcalculation methodologies have been developed including the use of soft computing techniques such as Neural Networks (NNs), Genetic Algorithms (GAs), etc. In this paper, Differential Evolution (DE), a stochastic parallel direct search evolution strategy optimization method is integrated with rapid surrogate mapping of Finite Element (FE) solutions ...
Greenhouse Gas Emission Analysis For Heated Pavement System, 2017 Iowa State University
Greenhouse Gas Emission Analysis For Heated Pavement System, Weibin Shen, Kasthurirangan Gopalakrishnan, Sunghwan Kim, Halil Ceylan
Anthropogenic greenhouse gas (GHG) emissions have become significant environmental indicators in analyzing the comparative environmental impacts of conventional and newly developed alternative systems or techniques. Life Cycle Assessment (LCA) is considered an accepted and systematic methodology to calculate the amount of carbon released from all the processes of a system/technique, helping users select the best environmental-friendly alternative. The use of automated heating based snow removal systems is gaining attention as an alternative strategy to traditional ice and snow removal practices such as the use of anti-icing chemicals and snowplowing vehicles. Most previous studies on heated pavement systems have focused ...
Effect Of Pcc Material Properties On Mepdg Jointed Plain Concrete Pavement (Jpcp) Performance Prediction, 2017 Iowa State University
Effect Of Pcc Material Properties On Mepdg Jointed Plain Concrete Pavement (Jpcp) Performance Prediction, Halil Ceylan, Sunghwan Kim, Charles W. Schwartz, Rui Li, Kasthurirangan Gopalakrishnan
This paper focuses on comprehensive sensitivity analyses of various rigid pavement scenarios. Jointed Plain Concrete Pavement (JPCP) sections designed for three traffic levels in each of five climate zones are evaluated in the sensitivity analyses. One-at-a-time (OAT) local sensitivity analysis was implemented using a design limit normalized sensitivity index (NSI) to provide both quantitative and qualitative sensitivity information. All portland cement concrete (PCC) material properties examined showed sensitivity to at least one rigid pavement performance measure. The highest ranked sensitive inputs for JPCP analysis include the PCC strength and stiffness properties and the curling and warping related properties. The findings ...
Minimizing Cementitious Content For Performance And Sustainability In Rigid Pavements, 2017 Iowa State University
Minimizing Cementitious Content For Performance And Sustainability In Rigid Pavements, Ezgi Yurdakul, Peter C. Taylor, Halil Ceylan, Fatih Bektas
The production of each ton of portland cement clinker emits approximately 1 ton of carbon dioxide. Therefore, there is a demand on the industry to reduce its carbon footprint by environmental agencies. A solution for the concrete construction industry is to use cement more efficiently. However, many concrete specifications impose minimum cementitious contents that may be in excess of those required to achieve desired durability and strength, leading to increased costs and increased carbon loading on the environment. In addition, in some cases, excessive cementitious content adversely affects concrete performance and durability by causing shrinkage related cracking. Therefore, minimizing the ...
Natural Selection Of Asphalt Mix Stiffness Predictive Models With Genetic Programming, 2017 Iowa State University
Natural Selection Of Asphalt Mix Stiffness Predictive Models With Genetic Programming, Kasthurirangan Gopalakrishnan, Sunghwan Kim, Halil Ceylan, Siddhartha K. Khaitan
Genetic Programming (GP) is a systematic, domain-independent evolutionary computation technique that stochastically evolves populations of computer programs to perform a user-defined task. Similar to Genetic Algorithms (GA) which evolves a population of individuals to better ones, GP iteratively transforms a population of computer programs into a new generation of programs by applying biologically inspired operations such as crossover, mutation, etc. In this paper, a population of Hot-Mix Asphalt (HMA) dynamic modulus stiffness prediction models is genetically evolved to better ones by applying the principles of genetic programming. The HMA dynamic modulus (|E*|), one of the stiffness measures, is the primary ...
Heated Transportation Infrastructure Systems: Existing Ande Emerging Technologies, 2017 Iowa State University
Heated Transportation Infrastructure Systems: Existing Ande Emerging Technologies, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim, W. Cord
Ice and snow on pavement surfaces cost the U.S. national economy in snow removal, damaged pavement and lost man-hours due to travel delay. Common practices for removing ice and snow from pavement surfaces include spraying anti-ice chemicals on the ground and deploying snowplowing vehicles. These methods are labor-intensive, occasionally ineffective at extremely low temperatures and have associated environmental concerns with possible contamination of nearby water bodies. Heated pavement systems (i.e., the concept of supplying heat to the pavement through an external or internal source) melt snow and ice without the need for anti-ice chemicals and snowplowing vehicles. A ...
Cost Comparison Of Alternative Airfield Snow Removal Methodologies, 2017 Iowa State University
Cost Comparison Of Alternative Airfield Snow Removal Methodologies, Pritha Anand, Halil Ceylan, Konstantina Gkritza, Peter Talor, Vasiliki Dimitra Pyrialakou, Sunghwan Kim, Kasthurirangan Gopalakrishnan
Maintaining operational safety and status of airport runways during snowfall events is a challenging issue that many airports are grappling with. Ice and snow impacts on transportation infrastructure systems add significant costs to the American economy in the form of snow removal, damaged pavement and lost productivity due to travel delays. Most transport category aircraft are prohibited from operating on runways covered by untreated ice or by more than ½ inch of snow or slush. Hence, it is imperative that both small and large airports maintain operational status during snowfall events to support the existing operations. Conventional ice and snow ...
Characterization Of Asphalt Materials Using X-Ray High-Resolution Computed Tomography Imaging Techniques, 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
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 Feasibility Study On Embedded Micro-Electromechanical Sensors And Systems (Mems) For Monitoring Highway Structures, Halil Ceylan, Kasthurirangan Gopalakrishnan, Peter Taylor, Pranav Shrotriya, Sunghwan Kim, Maxim Mikhaylovich Prokudin, Shiyun Wang, Ashley F. Buss, Jiake Zhang
Micro-electromechanical systems (MEMS) provide vast improvements over existing sensing methods in the context of structural health monitoring (SHM) of highway infrastructure systems, including improved system reliability, improved longevity and enhanced system performance, improved safety against natural hazards and vibrations, and a reduction in life cycle cost in both operating and maintaining the infrastructure. Advancements in MEMS technology and wireless sensor networks provide opportunities for long-term, continuous, real-time structural health monitoring of pavements and bridges at low cost within the context of sustainable infrastructure systems.
The primary objective of this research was to investigate the use of MEMS in highway structures ...
Developing Rigid Airport Pavement Multiple-Slab Response Models For Top-Down Cracking Mode Using Artificial Neural Networks, Halil Ceylan, Orhan Kaya, Adel Rezaei Tarahomi, Kasthurirangan Gopalakrishnan, Sunghwan Kim, David R. Brill
The Federal Aviation Administration (FAA) has recognized for some time that its current rigid 44 pavement design model, involving a single slab loaded at one edge by a single aircraft gear, is 45 inadequate to account for top-down cracking. Thus, one of the major observed failure modes for 46 rigid pavements is poorly represented in the FAA Rigid and Flexible Iterative Elastic Layer 47 Design (FAARFIELD) program. A research version of the FAARFIELD design software has 48 been developed (FAARFIELD 2.0), in which the single-slab three-dimensional finite element 49 (3D-FE) response model is replaced by a 4-slab 3D-FE model ...
Adaptive Neuro-Fuzzy Inference System-Based Backcalculation Approach To Airport Pavement Structural Analysis, 2017 Iowa State University
Adaptive Neuro-Fuzzy Inference System-Based Backcalculation Approach To Airport Pavement Structural Analysis, Kasthurirangan Gopalakrishnan, 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 ...
Comparative Performance Of Concrete Pavements With Recycled Concrete Aggregate (Rca) And Virgin Aggregate Subbases, Sunghwan Kim, Halil Ceylan, Kasthurirangan Gopalakrishnan, David J. White, Charles T. Jahren, Thang Huu Phan
Using recycled concrete aggregate (RCA) as base/subbase for road construction is alternative way to manage construction waste and reduces the need for virgin aggregates. This paper discusses the long-term performance of concrete pavements on RCA granular layer in comparison to concrete pavements on virgin aggregate granular layer. 18 representative RCA pavement sections across Iowa were primary selected considering state wide location and pavement age. Detailed visual distress surveys were conducted to identify the current pavement surface condition information and the primary distress on RCA granular layer pavement. The pavement information data for the surveyed RCA subbase sections and the ...
Application Of Shuffled Complex Evolution Optimization Approach To Concrete Pavement Backanalysis, 2017 Iowa State University
Application Of Shuffled Complex Evolution Optimization Approach To Concrete Pavement Backanalysis, Kasthurirangan Gopalakrishnan, 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 ...
A Predictive Model For Uniaxial Compressive Strength Of Carbonate Rocks From Schmidt Hardness, 2017 Iowa State University
A Predictive Model For Uniaxial Compressive Strength Of Carbonate Rocks From Schmidt Hardness, Murat Yurdakul, Halil Ceylan, Hurriyet Akdas
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 ...
Mepdg Work Plan Task No. 8: Validation Of Pavement Performance Curves For The Mechanistic-Empirical Pavement Design Guide, Halil Ceylan, Sunghwan Kim, Kasthurirangan Gopalakrishnan, Omar G. Smadi
The objective of this research is to determine whether the nationally calibrated performance models used in the Mechanistic-Empirical Pavement Design Guide (MEPDG) provide a reasonable prediction of actual field performance, and if the desired accuracy or correspondence exists between predicted and monitored performance for Iowa conditions. A comprehensive literature review was conducted to identify the MEPDG input parameters and the MEPDG verification/calibration process. Sensitivities of MEPDG input parameters to predictions were studied using different versions of the MEPDG software. Based on literature review and sensitivity analysis, a detailed verification procedure was developed. A total of sixteen different types of ...
Non-Destructive Evaluation Of Iowa Pavements Phase 2: Development Of A Fully Automated Software System For Rapid Analysis/Processing Of The Falling Weight Deflectometer Data, 2017 Iowa State University
Non-Destructive Evaluation Of Iowa Pavements Phase 2: Development Of A Fully Automated Software System For Rapid Analysis/Processing Of The Falling Weight Deflectometer Data, Halil Ceylan, Kasthurirangan Gopalakrishnan, Sunghwan Kim, Alper Guclu, M. Birkan Bayrak
The Office of Special Investigations at Iowa Department of Transportation (DOT) collects FWD data on regular basis to evaluate pavement structural conditions. The primary objective of this study was to develop a fully-automated software system for rapid processing of the FWD data along with a user manual. The software system automatically reads the FWD raw data collected by the JILS-20 type FWD machine that Iowa DOT owns, processes and analyzes the collected data with the rapid prediction algorithms developed during the phase I study. This system smoothly integrates the FWD data analysis algorithms and the computer program being used to ...
Investigation Of Electromagnetic Gauges For Determining In-Place Hma Density, 2017 Iowa State University
Investigation Of Electromagnetic Gauges For Determining In-Place Hma Density, Andrea N. Kvasnak, R. Christopher Williams, Halil Ceylan, Kasthurirangan Gopalakrishnan
Density is an important component of hot-mix asphalt (HMA) pavement quality and long-term performance. Insufficient density of an in-place HMA pavement is the most frequently cited construction-related performance problem.
This study evaluated the use of electromagnetic gauges to nondestructively determine densities. Field and laboratory measurements were taken with two electromagnetic gauges—a PaveTracker and a Pavement Quality Indicator (PQI). Test data were collected in the field during and after paving operations and also in a laboratory on field mixes compacted in the lab.
This study revealed that several mix- and project-specific factors affect electromagnetic gauge readings. Consequently, the implementation of ...