The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Khaled Ksaibati - One of the best experts on this subject based on the ideXlab platform.
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Assessing the applicability of the highway safety manual to Gravel Roads: A case study of Wyoming
Journal of Transportation Safety & Security, 2020Co-Authors: Ahmed Farid, Omar Albatayneh, Khaled KsaibatiAbstract:Gravel road safety is a crucial area of road safety since Gravel Roads represent a substantial proportion of the entirety of the nation’s roadway network. Also, Gravel Roads pose inherent hazards t...
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Complementary Modeling of Gravel Road Traffic-Generated Dust Levels Using Bayesian Regularization Feedforward Neural Networks and Binary Probit Regression
International Journal of Pavement Research and Technology, 2020Co-Authors: Omar Albatayneh, Milhan Moomen, Ahmed Farid, Khaled KsaibatiAbstract:Gravel Roads require extensive maintenance and rehabilitation. That is because of the dynamic behavior of Gravel road conditions. This study is aimed at investigating road condition factors affecting the traffic-generated dust on Gravel Roads. The study concerns Laramie County, Wyoming. The parametric binary probit regression structure and the non-parametric Bayesian regularization artificial neural network (BRANN) methods were implemented to model traffic-generated dust levels as a function of the factors that contribute to dust generation. The BRANNs method simplifies the model building process by precluding irrelevant and redundant weights of artificial neural networks (ANNs). In this study, the BRANN method is utilized with one single hidden layer using the MATLAB® function for neural networks. In the hidden layer, multiple neuron counts ranging from three to thirty were attempted. The parametric and non-parametric techniques mentioned were adopted to provide comprehensive insights into important factors that contribute to dust generation. Therefore, both techniques complement each other. A total of 206 Gravel road segments were used for model building for both analyses. As per the results of the BRANN model, it was found that twenty neurons produced the most accurate results. Furthermore, it was found that the BRANN model had more variables than the binary probit regression model, whereas the probit model provided general insights into the factors affecting the dust on Gravel Roads such as average travel speed and soil type. Also, it would be an easy-to-use method to assist local agencies and DOT practitioners in addressing the dust problems on Gravel Roads.
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effectiveness of the two chemical treatments cacl2 and mgcl2 as dust suppressants on Gravel Roads
International Journal of Pavement Engineering, 2020Co-Authors: Promothes Saha, Khaled KsaibatiAbstract:This study evaluates the effectiveness of dust treatments on Gravel Roads. Two dust suppressant types: CaCl2 and MgCl2 were used in this study on 26 Gravel roadway segments. Two dust measuring devi...
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developing an optimization tool for selecting Gravel Roads maintenance strategies using a genetic algorithm
Transportation Research Record, 2020Co-Authors: Waleed Aleadelat, Omar Albatayneh, Khaled KsaibatiAbstract:As part of the efforts by Wyoming Technology Transfer Center (WYT2/LTAP) to develop a Gravel Roads management system (GRMS) in Wyoming, this research study developed a user-friendly tool, using Jav...
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Developing an Optimization Tool for Selecting Gravel Roads Maintenance Strategies using a Genetic Algorithm
Transportation Research Record: Journal of the Transportation Research Board, 2020Co-Authors: Waleed Aleadelat, Omar Albatayneh, Khaled KsaibatiAbstract:As part of the efforts by Wyoming Technology Transfer Center (WYT2/LTAP) to develop a Gravel Roads management system (GRMS) in Wyoming, this research study developed a user-friendly tool, using JavaScript, which implements an optimization model based on genetic algorithms (GA). The developed tool will help decision makers and local agencies in managing Gravel Roads efficiently. Using this tool, a decision maker will be able to identify the most appropriate treatment type for each road, based on service level, estimated project costs, predicted road conditions, and whether to fund a project or not. The optimization model aims to maximize the overall condition of the Gravel Roads network subject to the average daily traffic (ADT) on each road. The developed tool can be applied to large-scale optimization problems (i.e., Gravel Roads network). The tool operates with minimal data requirements that are in line with procedures regularly followed at these agencies. In addition to having an engineered outcome, this tool can help local agencies in allocating their limited available funds efficiently, enhancing the planning process, maximizing the social welfare of the local economy, and promoting a sense of general satisfaction within the local community. A case study using data from Laramie County was used to validate this tool. The initial results were promising and in line with previous efforts to manage Gravel Roads in Wyoming.
George Huntington - One of the best experts on this subject based on the ideXlab platform.
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performance of recycled asphalt pavement in Gravel Roads
Transportation Research Record, 2011Co-Authors: Scott Koch, Khaled Ksaibati, George HuntingtonAbstract:Because more recycled asphalt pavement (RAP) has become available to use in roadways, the Wyoming Technology Transfer-Local Technical Assistance Program Center and two Wyoming counties saw a need to investigate the use of RAP in Gravel Roads. The Wyoming Department of Transportation along with the Mountain Plains Consortium funded this study. The investigation explored the use of RAP as a means of dust suppression while considering road serviceability. Test sections were constructed in the two counties and were monitored for dust loss by means of the Colorado State University dustometer. Surface distress evaluations of the test sections were performed following a technique developed by the U.S. Army Corps of Engineers in Unsurfaced Road Maintenance Management (Special Report 92-26). The data collected were statistically summarized and then analyzed. The performance of RAP sections was compared with that of Gravel control sections. This comparison allowed fundamental conclusions and recommendations to be m...
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improvement recommendations for unsealed Gravel Roads
Transportation Research Record, 2011Co-Authors: George Huntington, Khaled KsaibatiAbstract:A method was developed to recommend improvements for unsealed earth and Gravel Roads that are not up to the standard expected for their functional class. As part of a pilot asset management program carried out by the Wyoming Technology Transfer Center, Roads were rated for several distresses, including corrugations-washboards, rutting, potholes, loose aggregate, drainage, dust, and overall condition by using a visual survey method. These ratings were used to calculate a surfacing serviceability index (SSI) for each road section. This SSI was compared with the minimum acceptable SSI for the section's functional class. When the section's SSI was below this threshold value, improvement tasks were selected from a decision matrix, and the most expensive task was recommended to address the section's inadequate surface condition. This process allows an agency to present its elected officials with a list of Roads in their network that need improvement, along with an estimate of the cost of these improvements. The...
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Implementation Guide for the Management of Unsealed Gravel Roads
Transportation Research Record, 2011Co-Authors: George Huntington, Khaled KsaibatiAbstract:To address the current lack of a Gravel Roads management system (GRMS) appropriate for the rural agencies of the Intermountain West and the Great Plains, the Wyoming Technology Transfer Center (T2/LTAP) consulted with a volunteer group of experts and practitioners in the fields of unsealed earth and Gravel Roads and roadway management to put together a set of recommendations and guidelines for managing unsealed Roads. This paper describes and summarizes the Gravel Roads management methodology developed by T2/LTAP under the guidance of this group. Steps in implementing a GRMS are described, beginning with an assessment stage in which an agency evaluates its current unsealed Roads information management and the resources available to improve it. Next, three elements of a GRMS are described: data management, inventory, and data collection. Eight maintenance tasks for unsealed Roads are described: blading, reshaping, reGraveling, dust control, stabilization, isolated repairs, major work, and drainage maintena...
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Unsealed Gravel Road Management Systems Programming and Data Management
2011Co-Authors: George Huntington, Khaled KsaibatiAbstract:This paper summarizes the processes a programmer or data manager should go through when assisting with implementing or upgrading an unsealed Gravel Roads management system (GRMS). It describes the process of getting critical inputs from Gravel road managers, the initial and ongoing inputs to a GRMS, the algorithms that should be used to analyze data inputs, and database structures for storing and managing the information needed to operate a GRMS. A cyclic maintenance scheduling procedure, triggered maintenance programs and network-level outputs, such as financial tables and performance assessments, are described. Issues relating to how Gravel Roads data are collected are discussed, particularly the effects of gathering data for accountants rather than for engineers. To address this issue, eight dirt and Gravel road maintenance tasks are proposed.
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Volume 3 Gravel Roads Management: Programming Guide
2010Co-Authors: George Huntington, Khaled KsaibatiAbstract:This report establishes procedures for managing dirt and Gravel Roads, with a primary focus on smaller agencies, such as Wyoming counties, that must manage their Roads with very limited resources. The report strives, first, to guide and assist smaller agencies by implementing asset and pavement management principles and, second, to encourage and facilitate the development of Gravel Roads management software. The overall effort required to implement a Gravel Roads management system (GRMS) for local agencies must be minimal. Data collection efforts must be limited and the analysis must be simple and transparent. The four basic steps are: assessment; inventory; cost and maintenance history, and condition monitoring. This report is divided into three volumes. FHWA-WY-10/03F Volume 1 “Gravel Roads Management.” This section outlines the Background, Problem Statement, Objectives, Report Organization, Analytical Methods, and Summary and Conclusions. FHWA-WY-10/03F Volume 2 “Gravel Roads Management: Implementation Guide.” This section is designed to assist local road and street departments with implementation or improvement of a Gravel Roads management system. It is written primarily for road managers tasked with acquiring the necessary information to develop an information systems process. FHWA-WY-10/03F Volume 3 “Gravel Roads Management: Programming Guide. This section is intended to assist programmers and database managers with programming the information needed to implement a Gravel Roads management system.
Sunanda Dissanayake - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of Criteria for Setting Speed Limits on Gravel Roads
Journal of Transportation Engineering, 2011Co-Authors: Sunanda Dissanayake, Litao LiuAbstract:Even though speed limits of Gravel Roads are typically set based on statutory guidelines, there are some instances where exceptions are allowed and in place. In the absence of detailed literature on the subject, this study made an effort to evaluate and compare two criteria used in setting speed limits on low-volume Gravel Roads, with the intention of providing guidelines for future use. Field speed data were collected at a number of straight, level sections of Gravel Roads in Kansas where there is sufficient sight distance. Several sites located in two adjoining counties that use two different criteria for setting speed limits were also specifically selected for comparison purposes. One of the two counties adopts 35-mph speed limits on Gravel Roads and posts speed limit signs similar to those on paved Roads. Characteristics of Gravel Roads in the adjoining county are very similar except that the speed limit is governed by the statutory limit (55 mph) and not posted. Collected actual speed data indicated no significant differences between the two speed data sets. In addition to operational speed comparisons, crash experience was also taken into consideration, which showed no major differences in terms of safety. When looking at the findings of this study, it is clear that lowered, posted speed limit values on Gravel Roads have not necessarily helped in improving either operational conditions or safety. Rather, reduced posted speed limits on Gravel Roads have increased the percentage of speed limit violators. Accordingly, care should be taken in making such decisions in the future for new situations.
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Geometric Design and Other Characteristics Affecting Operating SpeedsOn Gravel Roads
2010Co-Authors: Sunanda Dissanayake, Litao LiuAbstract:In the United States, there are nearly 1.6 million miles of unpaved Roads, which approximately represent about 53% of all Roads and consist mainly of Gravel Roads. Even though such Gravel Roads carry low volumes, they provide an invaluable service to the mobility and transportation needs of people living in rural areas. Operating speed on the other hand is extremely important for any type of a roadway. Even though speed limits of Gravel Roads are typically set based on statutory guidelines there are some instances where exceptions are in place. Other characteristics of Gravel Roads also vary significantly across Gravel Roads. Accordingly, the objective of this study was to evaluate various factors affecting the operating speeds on Gravel Roads. Field speed data were collected at number of sites located in the state of Kansas using automatic traffic data counters. Based on the speed data collected, comparisons were made based on various characteristics and simple linear regression models were developed to predict 85th speed and the mean speed of vehicles on Gravel Roads. The factors looked into and evaluated in this study include surface type, roadway width, speed limit, and percentage of heavy vehicles. Results of this study indicated that the 85th percentile speeds on Gravel Roads are affected by surface type, road width, and the percentage of heavy vehicles. Interestingly the speed limit was not a predictor of the operating speeds on Gravel Roads. Lowered posted speed limit values on Gravel Roads have also not helped in reducing operating speeds, but have increased the number and percentage of speed limit violators.
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factors affecting crash severity on Gravel Roads
Journal of Transportation Safety & Security, 2009Co-Authors: Litao Liu, Sunanda DissanayakeAbstract:This study focused on the characteristics of crashes reported on Gravel Roads, with the objective of identifying factors affecting severity of crashes on such Roads. Crash data from Kansas over a 10 year period was used in the analysis. Logistic regression models were developed to estimate the probability of having a crash of different level of severity for a given set of explanatory variables. The regression modeling considered 29 candidate variables related to driver, road, environment, and collision type, which have been recorded by the police. It was found that multiple factors were very significant in these models, such as safety equipment usage, driver ejection, alcohol involvement, speed limit, and some driver-related factors. Existence of these factors was very likely to result in high-severity crashes on Gravel Roads, compared to the circumstances without them. The magnitude of such contributing effects was also estimated by computing the conditional odds ratios for individual predictors.
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Criteria for Setting Speed Limits on Low-Volume Gravel Roads
2009Co-Authors: Sunanda Dissanayake, Liu LitaoAbstract:Even though speed limits of Gravel Roads are typically set based on statutory guidelines, there are some instances where exceptions are allowed and in place. In the absence of detailed literature on the subject, this study made an effort to evaluate and compare two criteria used in setting speed limits on low volume Gravel Roads, with the intention of providing guidelines for future use. Field speed data were collected at number of straight, level sections of Gravel Roads in Kansas. Several sites located in two adjoining counties that use two different criteria for setting speed limits were also specifically selected for comparison purposes. One of the two counties adopts 35 mph speed limits on Gravel Roads and posts the speed limit signs similar to those on paved Roads. Characteristics of Gravel Roads in the adjoining county are very similar except the fact that the speed limit is governed by the statutory limit (55 mph) and not posted. Collected actual speed data indicated that there are no significant differences between the two speed data sets. In addition to operational speed comparisons, crash experience was also taken into consideration, where it showed no major differences. When looking at the findings of this study, it is clear that lowered posted speed limit values on Gravel Roads has not necessarily helped in improving either operational conditions or safety. Rather, reduced posted speed limits on Gravel Roads have increased the percentage of speed limit violators. Accordingly, care should be taken in making such decisions in the future for new situations.
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Examination of Factors Affecting Crash Severity on Gravel Roads
2009Co-Authors: Liu Litao, Sunanda DissanayakeAbstract:This study focused on the characteristics of crashes that were reported on Gravel Roads with the objective of identifying factors affecting severity of injury crashes on Gravel Roads. Crash data from Kansas over a 10-year period was used in the analysis. Logistic regression models were developed to estimate the probability of having an injury crash of different level of severity for a given set of explanatory variables. The regression modeling considered about thirty candidate factors related to driver, road, environment, and collision types, which have been recorded by the police. It was found that a couple of factors were very significant in these models, such as safety equipment usage, driver ejection, alcohol involvement, speed limit, and some driver-related factors. The existence of these factors was very likely to result in high severity injury crashes, compared to the circumstances without them. The magnitude of such contributing effects was also estimated by computing the conditional odds ratios for individual predictors.
Donatas Čygas - One of the best experts on this subject based on the ideXlab platform.
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Soft Asphalt and Double Otta Seal—Self-Healing Sustainable Techniques for Low-Volume Gravel Road Rehabilitation
Sustainability, 2018Co-Authors: Audrius Vaitkus, Judita Gražulytė, Faustina Tuminienė, Viktoras Vorobjovas, Donatas ČygasAbstract:Increased traffic flow on low-volume Gravel Roads and deficiencies of national road infrastructure, are increasingly apparent in Lithuania. Gravel Roads do not comply with requirements, resulting in low driving comfort, longer travelling time, faster vehicle amortization, and dustiness. The control of dustiness is one of the most important road maintenance activities on Gravel Roads. Another important issue is the assurance of required driving comfort and safety. Soft asphalt and Otta Seal technologies were proposed as a sustainable solution for the improvement of low-volume Roads in Lithuania. Five Gravel Roads were constructed with soft asphalt, and 13 Gravel Roads were sealed with double Otta Seal, in 2012. The main aim of this research was to check soft asphalt and double Otta Seal’s ability to self-heal, on the basis of the results of the qualitative visual assessment of pavement defects and distress. The qualitative visual assessment was carried out twice a year following the opening of the rehabilitated road sections. The results confirmed soft asphalt and double Otta Seal’s ability to self-heal. The healing effect was more than 13% and 19% on Roads with soft asphalt and double Otta Seal, respectively. In addition, on some Roads, all cracks observed in spring self-healed during summer
Tauno Mäkiö - One of the best experts on this subject based on the ideXlab platform.
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Turning Deteriorated Paved Roads Back into Gravel Roads: Sheer Lunacy or Sustainable Maintenance Policy?
Transportation Research Record: Journal of the Transportation Research Board, 2003Co-Authors: Jyri Mustonen, Janne Lintilä, Tauno MäkiöAbstract:In the late 1980s, many Finnish low-volume Gravel Roads were paved. This option was reasonable at that time because the price of bitumen was exceptionally low. No heavy structural rehabilitation was carried out on these Roads before paving. It was assumed that these cheap and light pavements would last some 5 years. Now many of those Roads have reached 10 to 15 years in age, still without any proper reconstruction, and are becoming increasingly deteriorated. For almost a decade now, the Finnish government has been reducing its spending on public Roads. Maintenance and repair efforts have been concentrated on the main road network, and the minor network has deteriorated more and more. Calculations show that from the road agency’s point of view, upkeep of Gravel Roads is economically feasible compared with maintaining paved Roads that are in poor condition. Therefore, road authorities have converted some of these paved low-volume Roads back to Gravel Roads. In 2001, the Häme, Turku, and Uusimaa road districts agreed on common principles for these actions. Furthermore, they described minimum requirements for each case in which a paved road in poor condition was turned into a Gravel road. Public opposition and political resistance were quite strong before these actions, since the Gravel Roads are seen as a decline of service level. People living along the road, however, generally admit that new Gravel Roads are more comfortable to drive on throughout the year than old deteriorated pavements. The road agency still has to focus on problems such as dust.
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turning deteriorated paved Roads back into Gravel Roads sheer lunacy or sustainable maintenance policy
Transportation Research Record, 2003Co-Authors: Jyri Mustonen, Janne Lintilä, Tauno MäkiöAbstract:In the late 1980s, many Finnish low-volume Gravel Roads were paved. This option was reasonable at that time because the price of bitumen was exceptionally low. No heavy structural rehabilitation was carried out on these Roads before paving. It was assumed that these cheap and light pavements would last some 5 years. Now many of those Roads have reached 10 to 15 years in age, still without any proper reconstruction, and are becoming increasingly deteriorated. For almost a decade now, the Finnish government has been reducing its spending on public Roads. Maintenance and repair efforts have been concentrated on the main road network, and the minor network has deteriorated more and more. Calculations show that from the road agency's point of view, upkeep of Gravel Roads is economically feasible compared with maintaining paved Roads that are in poor condition. Therefore, road authorities have converted some of these paved low-volume Roads back to Gravel Roads. In 2001, the Hame, Turku, and Uusimaa road distric...
