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Brian K Diefenderfer - One of the best experts on this subject based on the ideXlab platform.
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Developing a Network-Level Structural Capacity Index for Structural Evaluation of Pavements
2013Co-Authors: James Bryce, Gerardo W Flintsch, Samer W Katicha, Brian K DiefenderferAbstract:The objective of this project was to develop a structural index for use in Network-Level pavement evaluation to facilitate the inclusion of the pavement’s structural condition in pavement management applications. The primary goal of Network-Level pavement management is to provide the best service to the users for the available, often limited, resources. Pavement condition can be described in terms of functional and structural condition. The current widespread practice of Network-Level pavement evaluation is to consider only the functional pavement condition. This practice results in suggested treatments that are often under-designed or over-designed when considered in more detail at the project Level. The disagreement can be reduced by considering the structural capacity of the pavements as part of a Network-Level decision process. This study developed a flexible pavement structural index to use for Network-Level pavement applications. Available pavement condition data were used to conduct a sensitivity analysis of the index, and example applications were tested. The results indicated that including the structural index developed, named the Modified Structural Index (MSI), into the Network-Level decision process minimized the discrepancy between Network-Level predictions and project-Level decisions when compared to the current Network-Level decision-making process. A pilot implementation of the MSI showed that it can be used to support various pavement management decision processes, such as Network-Level structural screening, deterioration modeling, and development of structural performance measures. The pilot test also indicated that the impact of the structural condition of the pavement on the performance of a maintenance treatment and its impact on life-cycle costs can be quantified.
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developing a Network Level structural capacity index for asphalt pavements
Journal of Transportation Engineering-asce, 2013Co-Authors: James Bryce, Gerardo W Flintsch, Samer W Katicha, Brian K DiefenderferAbstract:This paper presents a Network-Level structural capacity indicator for asphalt pavements in the state of Virginia. A literature review revealed that several Network-Level structural capacity indexes have been proposed, and a number of states use structural capacity measures in their Network-Level decision processes. Some decision methods and structural indexes are compared in this paper using Network-Level deflection data collected using the falling weight deflectometer and distress data from tests conducted on Virginia interstates. One index that is based on the structural number concept, the Structural Capacity Index, is found to produce Network-Level decisions that most closely match project-Level work done by the Virginia Department of Transportation during the 2008 construction season. The index was adopted, and its sensitivity to various input parameters was determined. Furthermore, the impact of the structural capacity of the pavement on the service life of a pavement maintenance treatment was clearly established in this paper. Equations to define the service life of a corrective maintenance treatment as a function of the structural condition of the pavement are also presented in this paper.
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Enhancing Network-Level Decision Making Through the Use of a Structural Capacity Index
Transportation Research Record, 2013Co-Authors: James Bryce, Gerardo W Flintsch, Samer W Katicha, Brian K DiefenderferAbstract:The objective of this study was to show potential applications of a Network-Level structural index developed for evaluation of flexible pavements. First, several potential applications for implementation of Network-Level structural measures were identified, and then data from the state of Virginia were used to modify the proposed applications for the index and show examples of them. Several applications were validated with data from Network-Level deflection testing with the falling weight deflectometer on Interstate highways in Virginia and data from the Virginia Department of Transportation Pavement Management System. The results of the research indicate that including the structural index in the Network-Level decision process can facilitate a greater understanding of the behavior of the performance of a pavement. Furthermore, the index that was proposed for Network-Level evaluation of flexible pavements in Virginia was used to develop enhanced deterioration models for particular pavement treatments and ...
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Development and Implementation of Network-Level Selection of Pavement Maintenance and Rehabilitation Strategy: Virginia Practice
2009Co-Authors: Raja A. Shekharan, Tanveer Chowdhury, Brian K DiefenderferAbstract:Tools for Network-Level pavement maintenance and rehabilitation (M&R) decisions for Virginia highways have evolved over time from the use of composite condition index values to the use of more comprehensive distress-based decision matrices. This paper presents the current Network-Level pavement M&R planning practices in the Virginia Department of Transportation and explores the enhancement of existing distress-based M&R decision matrices to incorporate additional decision factors of traffic, structural capacity, and pavement surface age, which are as important as surface distresses. The authors found that using supplementary decision trees incorporating these decision factors allows more consistency and flexibility than simply enlarging existing distress-based decision matrices, which are already complex. Implementation of the enhanced M&R planning framework leads to a more accurate estimate of pavement preservation needs, a closer match between Network-Level assumptions used in pavement management and actual practice, and hence a better control of statewide Network condition.
James Bryce - One of the best experts on this subject based on the ideXlab platform.
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Developing a Network-Level Structural Capacity Index for Structural Evaluation of Pavements
2013Co-Authors: James Bryce, Gerardo W Flintsch, Samer W Katicha, Brian K DiefenderferAbstract:The objective of this project was to develop a structural index for use in Network-Level pavement evaluation to facilitate the inclusion of the pavement’s structural condition in pavement management applications. The primary goal of Network-Level pavement management is to provide the best service to the users for the available, often limited, resources. Pavement condition can be described in terms of functional and structural condition. The current widespread practice of Network-Level pavement evaluation is to consider only the functional pavement condition. This practice results in suggested treatments that are often under-designed or over-designed when considered in more detail at the project Level. The disagreement can be reduced by considering the structural capacity of the pavements as part of a Network-Level decision process. This study developed a flexible pavement structural index to use for Network-Level pavement applications. Available pavement condition data were used to conduct a sensitivity analysis of the index, and example applications were tested. The results indicated that including the structural index developed, named the Modified Structural Index (MSI), into the Network-Level decision process minimized the discrepancy between Network-Level predictions and project-Level decisions when compared to the current Network-Level decision-making process. A pilot implementation of the MSI showed that it can be used to support various pavement management decision processes, such as Network-Level structural screening, deterioration modeling, and development of structural performance measures. The pilot test also indicated that the impact of the structural condition of the pavement on the performance of a maintenance treatment and its impact on life-cycle costs can be quantified.
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developing a Network Level structural capacity index for asphalt pavements
Journal of Transportation Engineering-asce, 2013Co-Authors: James Bryce, Gerardo W Flintsch, Samer W Katicha, Brian K DiefenderferAbstract:This paper presents a Network-Level structural capacity indicator for asphalt pavements in the state of Virginia. A literature review revealed that several Network-Level structural capacity indexes have been proposed, and a number of states use structural capacity measures in their Network-Level decision processes. Some decision methods and structural indexes are compared in this paper using Network-Level deflection data collected using the falling weight deflectometer and distress data from tests conducted on Virginia interstates. One index that is based on the structural number concept, the Structural Capacity Index, is found to produce Network-Level decisions that most closely match project-Level work done by the Virginia Department of Transportation during the 2008 construction season. The index was adopted, and its sensitivity to various input parameters was determined. Furthermore, the impact of the structural capacity of the pavement on the service life of a pavement maintenance treatment was clearly established in this paper. Equations to define the service life of a corrective maintenance treatment as a function of the structural condition of the pavement are also presented in this paper.
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Enhancing Network-Level Decision Making Through the Use of a Structural Capacity Index
Transportation Research Record, 2013Co-Authors: James Bryce, Gerardo W Flintsch, Samer W Katicha, Brian K DiefenderferAbstract:The objective of this study was to show potential applications of a Network-Level structural index developed for evaluation of flexible pavements. First, several potential applications for implementation of Network-Level structural measures were identified, and then data from the state of Virginia were used to modify the proposed applications for the index and show examples of them. Several applications were validated with data from Network-Level deflection testing with the falling weight deflectometer on Interstate highways in Virginia and data from the Virginia Department of Transportation Pavement Management System. The results of the research indicate that including the structural index in the Network-Level decision process can facilitate a greater understanding of the behavior of the performance of a pavement. Furthermore, the index that was proposed for Network-Level evaluation of flexible pavements in Virginia was used to develop enhanced deterioration models for particular pavement treatments and ...
Gerardo W Flintsch - One of the best experts on this subject based on the ideXlab platform.
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Application of Traffic Speed Deflectometer for Network-Level Pavement Management:
Transportation Research Record: Journal of the Transportation Research Board, 2018Co-Authors: Shivesh Shrestha, Gerardo W Flintsch, Samer W Katicha, Senthilmurugan ThyagarajanAbstract:In this paper, the traffic speed deflectometer (TSD), a device used for Network Level structural evaluation, is assessed. TSD testing was performed in nine states on a total of 5,928 miles (some re...
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Developing a Network-Level Structural Capacity Index for Structural Evaluation of Pavements
2013Co-Authors: James Bryce, Gerardo W Flintsch, Samer W Katicha, Brian K DiefenderferAbstract:The objective of this project was to develop a structural index for use in Network-Level pavement evaluation to facilitate the inclusion of the pavement’s structural condition in pavement management applications. The primary goal of Network-Level pavement management is to provide the best service to the users for the available, often limited, resources. Pavement condition can be described in terms of functional and structural condition. The current widespread practice of Network-Level pavement evaluation is to consider only the functional pavement condition. This practice results in suggested treatments that are often under-designed or over-designed when considered in more detail at the project Level. The disagreement can be reduced by considering the structural capacity of the pavements as part of a Network-Level decision process. This study developed a flexible pavement structural index to use for Network-Level pavement applications. Available pavement condition data were used to conduct a sensitivity analysis of the index, and example applications were tested. The results indicated that including the structural index developed, named the Modified Structural Index (MSI), into the Network-Level decision process minimized the discrepancy between Network-Level predictions and project-Level decisions when compared to the current Network-Level decision-making process. A pilot implementation of the MSI showed that it can be used to support various pavement management decision processes, such as Network-Level structural screening, deterioration modeling, and development of structural performance measures. The pilot test also indicated that the impact of the structural condition of the pavement on the performance of a maintenance treatment and its impact on life-cycle costs can be quantified.
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developing a Network Level structural capacity index for asphalt pavements
Journal of Transportation Engineering-asce, 2013Co-Authors: James Bryce, Gerardo W Flintsch, Samer W Katicha, Brian K DiefenderferAbstract:This paper presents a Network-Level structural capacity indicator for asphalt pavements in the state of Virginia. A literature review revealed that several Network-Level structural capacity indexes have been proposed, and a number of states use structural capacity measures in their Network-Level decision processes. Some decision methods and structural indexes are compared in this paper using Network-Level deflection data collected using the falling weight deflectometer and distress data from tests conducted on Virginia interstates. One index that is based on the structural number concept, the Structural Capacity Index, is found to produce Network-Level decisions that most closely match project-Level work done by the Virginia Department of Transportation during the 2008 construction season. The index was adopted, and its sensitivity to various input parameters was determined. Furthermore, the impact of the structural capacity of the pavement on the service life of a pavement maintenance treatment was clearly established in this paper. Equations to define the service life of a corrective maintenance treatment as a function of the structural condition of the pavement are also presented in this paper.
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Enhancing Network-Level Decision Making Through the Use of a Structural Capacity Index
Transportation Research Record, 2013Co-Authors: James Bryce, Gerardo W Flintsch, Samer W Katicha, Brian K DiefenderferAbstract:The objective of this study was to show potential applications of a Network-Level structural index developed for evaluation of flexible pavements. First, several potential applications for implementation of Network-Level structural measures were identified, and then data from the state of Virginia were used to modify the proposed applications for the index and show examples of them. Several applications were validated with data from Network-Level deflection testing with the falling weight deflectometer on Interstate highways in Virginia and data from the Virginia Department of Transportation Pavement Management System. The results of the research indicate that including the structural index in the Network-Level decision process can facilitate a greater understanding of the behavior of the performance of a pavement. Furthermore, the index that was proposed for Network-Level evaluation of flexible pavements in Virginia was used to develop enhanced deterioration models for particular pavement treatments and ...
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A Network-Level Optimization Model for Pavement Maintenance and Rehabilitation Programming
2007Co-Authors: Gerardo W FlintschAbstract:Network Level pavement management systems support the development of pavement maintenance and rehabilitation (M&R) programs and budgets over an entire pavement Network. They provide tools and methods for resource allocations and project prioritization. This paper proposes a practical decision-support model for determining optimal M&R Network-Level policies based on goal programming. The model can handle multiple incommensurable and conflicting objectives while considering probabilistic constraints related to the available budget and agency pavement condition performance targets. The optimization approach builds on previous formulations and adds probabilistic considerations that make the solution more stable and allow incorporating risk in decision-making process. Two optimization objectives, maximization of the total M&R effectiveness and minimization of the total M&R cost, were used to illustrate the process. The implementation of the model in a simple case study showed that its application is practical for supporting the management of pavement M&R that reflects agency goals, resource limitations, and performance targets.
Zhanmin Zhang - One of the best experts on this subject based on the ideXlab platform.
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Improvements to the structural condition index (SCI) for pavement structural evaluation at Network Level
International Journal of Pavement Engineering, 2015Co-Authors: Boo Hyun Nam, Michael R Murphy, Moo Yeon Kim, Zhanmin ZhangAbstract:Structural evaluation provides valuable information about the expected behaviour and response of pavements and can be used at the Network Level of pavement management to prioritise projects. The falling weight deflectometer (FWD) can be used to identify the beginning and end of management sections and group pavement sections with similar structural capacities. The structural condition index (SCI) was developed as a screening tool for the pavement Network-Level evaluation, and the FWD data are used to determine the SCI. For the successful implementation of the SCI concept at the Network Level, one of the critical issues is the accuracy of the index. This article evaluates the accuracy of the SCI and also discusses a concept and procedure how to improve the SCI and its algorithm for low-volume flexible pavements. A case study (Texas) illustrates that the original SCI algorithm underestimates the existing structural condition, resulting in overestimated treatments in the pavement maintenance and rehabilitation.
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Improved structural condition index for pavement evaluation at Network Level
Airfield and Highway Pavement 2013, 2013Co-Authors: Boo Hyun Nam, Michael R Murphy, Zhanmin Zhang, Mike ArellanoAbstract:Pavement's structural evaluation that provides valuable information about the expected behavior and response can be used at the Network Level of pavement management to prioritize projects. A deflection measurement such as the falling weight deflectometer (FWD) can be used to identify problematic areas and group pavement sections with similar structural capacities. The structural condition index (SCI), a ratio of the existing structural number (SNeff) and the required SN (SNreq), is a screening tool for the pavement Network-Level management. For the successful implementation of the SCI concept at the Network Level, one critical issue is the accuracy of the index in evaluating the structural and deterioration conditions of the pavements. A field visit illustrates that the current SCI analysis underestimates the existing structural condition and results in overestimated treatments in pavement maintenance and rehabilitation. This paper presents and discusses how to improve the current SCI algorithm, mainly enhancing the estimation of the SNreq.
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Pavement Structural Evaluation at Network Level Using Falling-Weight Deflectometer
2012Co-Authors: Boo Hyun Nam, Michael R Murphy, Zhanmin Zhang, Jaewon Hwang, Miguel ArellanoAbstract:Structural evaluation provides valuable information about the expected behavior and response of pavements and can be used at the Network Level of pavement management to prioritize projects. A deflection test, such as the Falling Weight Deflectometer, can be used to identify the beginning and end of management sections and group pavement sections with similar structural capacities. However, due to the expense of data collection and analysis, and need for improved analysis methods agencies may be hesitant to perform structural capacity testing at the Network Level. Recently, the Structural Condition Index (SCI) was developed for the Texas Department of Transportation (TxDOT) as a screening tool at the Network Level to discriminate between pavements that need structural reinforcement from those that do not. For the successful implementation of the SCI concept at the Network Level, one of the critical issues is the accuracy of the index in accessing the structural and deterioration conditions of the pavements. This paper evaluates the accuracy of the SCI and also discusses how to improve the SCI and its algorithm for low volume roads (i.e. farm-to-market road). A case study illustrates that the SCI v1 underestimates the existing structural condition and results in an overestimated treatments in the pavement maintenance and rehabilitation. In this and previous studies, the SCI has only been evaluated for Asphalt Concrete Pavements (ACP) and thin surfaced treated pavements. Portland Cement Concrete (PCC) pavements have not been addressed.
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Implementation Study of a Structural Condition Index at the Network Level
2011Co-Authors: Zhanmin Zhang, Michael R Murphy, Sruthi PeddibhotlaAbstract:It is common practice for highway agencies to apply seal coats, thin overlays, and other types of surface treatments to preserve the highway Network by improving the pavement surface condition. These maintenance treatments serve as a temporary improvement of the surface condition; however, they do not remedy any structural deficiency associated with the pavements. In order for such preventive maintenance treatments to be cost-effective, pavements receiving these treatments should have adequate structural capacity; otherwise, the preventive treatments will fail before they reach the normally expected service life, resulting in an ineffective use of maintenance resources. Although pavement condition data, such as visual distress and ride quality, provide a good indication of the overall Network-Level pavement condition, they do not give a direct measure of the structural adequacy of a pavement. To address this issue, it is proposed to implement a Network-Level Structural Condition Index based on the Falling Weight Deflectometer deflection data. This implementation study focuses on the validation of a Structural Condition Index developed under a previous study and the development of various criteria essential for the implementation of the Structural Condition Index at the Network Level, including the minimum sample size for collecting the Falling Weight Deflectometer deflection data. The validation was conducted with 180 pavement sections covering a wide range of pavement conditions and five climatic regions in Texas. The validation result shows that the Structural Condition Index is an effective measurement of the pavement structural condition at the Network Level.
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determination of required falling weight deflectometer testing frequency for pavement structural evaluation at the Network Level
Journal of Transportation Engineering-asce, 2006Co-Authors: Ivan Damnjanovic, Zhanmin ZhangAbstract:Recently, a structural condition index (SCI) was developed for the Texas Department of Transportation as a screening tool to discriminate between pavements that need structural reinforcement from those that do not. For the successful implementation of the SCI concept at the Network Level, one of the critical issues is to determine the minimum falling weight deflectometer (FWD) testing frequency. The paper discusses how to determine the required FWD testing frequency, or the required FWD test spacing needed for implementing the SCI at the Network Level. In this study, the risk-based method was employed, where the variance of the SCI at the Network Level was assessed by randomly selecting a small sample of the pavement sections that were representative of the whole Network. Due to the limited number of such sections and the lack of knowledge of underlying distribution of the SCI variances at the Network Level, the bootstrap method was used to obtain the mean and the confidence intervals on the mean of the SCI variances at the Network Level.
Emiliano Santarnecchi - One of the best experts on this subject based on the ideXlab platform.
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Network Level macroscale structural connectivity predicts propagation of transcranial magnetic stimulation
NeuroImage, 2021Co-Authors: Davide Momi, Recep Ali Ozdemir, Ehsan Tadayon, Pierre Boucher, Mouhsin M Shafi, Alvaro Pascualleone, Emiliano SantarnecchiAbstract:Abstract Information processing in the brain is mediated by structural white matter pathways and is highly dependent on topological brain properties. Here we combined transcranial magnetic stimulation (TMS) with high-density electroencephalography (EEG) and Diffusion Weighted Imaging (DWI), specifically looking at macroscale connectivity to understand whether regional, Network-Level or whole-brain structural properties are more responsible for stimulus propagation. Neuronavigated TMS pulses were delivered over two individually defined nodes of the default mode (DMN) and dorsal attention (DAN) Networks in a group of healthy subjects, with test-retest reliability assessed 1-month apart. TMS-evoked activity was predicted by the modularity and structural integrity of the stimulated Network rather than the targeted region(s) or the whole-brain connectivity, suggesting Network-Level structural connectivity as more relevant than local brain properties in shaping TMS signal propagation. The importance of Network structural connectome was unveiled only by evoked activity, but not resting-state data. Future clinicals interventions might enhance target engagement by adopting DWI-guided, Network-focused TMS.
