The Experts below are selected from a list of 225 Experts worldwide ranked by ideXlab platform
Erol Tutumluer - One of the best experts on this subject based on the ideXlab platform.
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Stone blowing as a remedial measure to mitigate differential movement problems at railroad Bridge Approaches
Proceedings of the Institution of Mechanical Engineers Part F: Journal of Rail and Rapid Transit, 2018Co-Authors: Huseyin Boler, Debakanta Mishra, Erol Tutumluer, Steven Chrismer, James P. HyslipAbstract:Railroad track transitions such as Bridge Approaches often experience recurrent track geometry problems due to differential settlement between the Bridge and the adjacent track. The resulting “bump...
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deformation and dynamic load amplification trends at railroad Bridge Approaches effects caused by high speed passenger trains
Transportation Research Record, 2017Co-Authors: Debakanta Mishra, Erol Tutumluer, Huseyin Boler, Wenting Hou, James P. HyslipAbstract:Railroad track transitions such as Bridge Approaches may experience differential movements due to variations in track stiffness; impact loads due to train speed and excessive vibration; ballast settlement from fouling, degradation, or both; tie–ballast contact condition and gap; and settlement of fill, subgrade, and foundation layers. A research study completed recently at the University of Illinois focused on identifying the major causes of this differential movement and implementing suitable rehabilitation measures to mitigate recurrent problems with settlement and geometry. Transient and permanent deformation trends were observed in track substructure layers at two instrumented Bridge Approaches along the Amtrak Northeast Corridor. Multidepth deflectometer systems installed through crossties successfully recorded both permanent (plastic) and transient deformations of individual track substructure layers. Strain gauges mounted on the rail effectively measured vertical wheel loads applied during train pa...
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Deformation and Dynamic Load Amplification Trends at Railroad Bridge Approaches
Transportation Research Record: Journal of the Transportation Research Board, 2017Co-Authors: Debakanta Mishra, Erol Tutumluer, Huseyin Boler, Wenting Hou, James P. HyslipAbstract:Railroad track transitions such as Bridge Approaches may experience differential movements due to variations in track stiffness; impact loads due to train speed and excessive vibration; ballast settlement from fouling, degradation, or both; tie–ballast contact condition and gap; and settlement of fill, subgrade, and foundation layers. A research study completed recently at the University of Illinois focused on identifying the major causes of this differential movement and implementing suitable rehabilitation measures to mitigate recurrent problems with settlement and geometry. Transient and permanent deformation trends were observed in track substructure layers at two instrumented Bridge Approaches along the Amtrak Northeast Corridor. Multidepth deflectometer systems installed through crossties successfully recorded both permanent (plastic) and transient deformations of individual track substructure layers. Strain gauges mounted on the rail effectively measured vertical wheel loads applied during train passage and monitored the support conditions under the instrumented crossties. Track settlement (or permanent deformation) data revealed that the ballast layer was the primary source of differential movement contributing to recurrent settlement and geometry problems. Transient layer deformations recorded under train passage were higher in the ballast than in any other substructure layer. Transient displacement and wheel load data were consistently higher at near-Bridge locations than at open-track locations. Rail-mounted strain gauges indicated that load amplification levels were significantly higher at near-Bridge locations than at open-track locations.
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ballast settlement ramp to mitigate differential settlement in a Bridge transition zone
Transportation Research Record, 2015Co-Authors: Yu Qian, Youssef M A Hashash, Jamshid Ghaboussi, Erol Tutumluer, David D. DavisAbstract:Differential settlement in railroad track transitions, often associated with differences in track stiffness, may apply considerable impact load and may cause rapid deterioration of track geometry. Such differential settlement commonly seen in Bridge Approaches may lead to problems in ride comfort, track safety, and reliability. Ballast and subballast layers have been identified as a major cause of differential settlement related to the particulate nature of the aggregate deformation behavior causing degradation and breakdown associated with increased track usage. This paper describes an innovative field approach that successfully demonstrated the use of engineered ballast materials for reducing or mitigating the differential settlement problem in a Bridge transition zone. Discrete element method (DEM) simulations were used to predict full-scale track deformations of four ballast materials having different gradations and aggregate shape properties. An imaging device was used to create accurate particle siz...
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application of panda and geo endoscopy techniques for improved assessment of track substructure conditions at railroad Bridge Approaches
ASME ASCE IEEE 2015 Joint Rail Conference JRC 2015, 2015Co-Authors: Debakanta Mishra, Erol Tutumluer, Jonathan Gallier, Younes Haddani, Roland GourvesAbstract:An advanced technology for measuring track substructure conditions has been developed by Sol Solution in France. This technology, referred to as the PANDA® and Geo-Endoscopy® technique, comprises driving a variable energy cone penetration device into the track substructure using an instrumented anvil to collect strength (and modulus by correlation) profile with depth. Condition monitoring of the track substructure layers is accomplished through insertion of a camera into the same hole, also called Geoendoscopy®. The tests are commonly faster than Dynamic Cone Penetration (DCP) testing and cause negligible damage to the track substructure with the use of light and portable devices. This paper presents data from PANDA® and Geo-Endoscopy® testing efforts recently carried out under the scope of an ongoing research study at the University of Illinois. The primary objective was to relate the substructure layer properties to plastic layer deformations measured through advanced geotechnical instrumentation. Combined analysis of the PANDA®, Geo-Endoscopy®, and field instrumentation data has been used to highlight the reliability of this innovative technique towards improved evaluation of track substructure layer conditions.Copyright © 2015 by ASME
Debakanta Mishra - One of the best experts on this subject based on the ideXlab platform.
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Stone blowing as a remedial measure to mitigate differential movement problems at railroad Bridge Approaches
Proceedings of the Institution of Mechanical Engineers Part F: Journal of Rail and Rapid Transit, 2018Co-Authors: Huseyin Boler, Debakanta Mishra, Erol Tutumluer, Steven Chrismer, James P. HyslipAbstract:Railroad track transitions such as Bridge Approaches often experience recurrent track geometry problems due to differential settlement between the Bridge and the adjacent track. The resulting “bump...
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deformation and dynamic load amplification trends at railroad Bridge Approaches effects caused by high speed passenger trains
Transportation Research Record, 2017Co-Authors: Debakanta Mishra, Erol Tutumluer, Huseyin Boler, Wenting Hou, James P. HyslipAbstract:Railroad track transitions such as Bridge Approaches may experience differential movements due to variations in track stiffness; impact loads due to train speed and excessive vibration; ballast settlement from fouling, degradation, or both; tie–ballast contact condition and gap; and settlement of fill, subgrade, and foundation layers. A research study completed recently at the University of Illinois focused on identifying the major causes of this differential movement and implementing suitable rehabilitation measures to mitigate recurrent problems with settlement and geometry. Transient and permanent deformation trends were observed in track substructure layers at two instrumented Bridge Approaches along the Amtrak Northeast Corridor. Multidepth deflectometer systems installed through crossties successfully recorded both permanent (plastic) and transient deformations of individual track substructure layers. Strain gauges mounted on the rail effectively measured vertical wheel loads applied during train pa...
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Deformation and Dynamic Load Amplification Trends at Railroad Bridge Approaches
Transportation Research Record: Journal of the Transportation Research Board, 2017Co-Authors: Debakanta Mishra, Erol Tutumluer, Huseyin Boler, Wenting Hou, James P. HyslipAbstract:Railroad track transitions such as Bridge Approaches may experience differential movements due to variations in track stiffness; impact loads due to train speed and excessive vibration; ballast settlement from fouling, degradation, or both; tie–ballast contact condition and gap; and settlement of fill, subgrade, and foundation layers. A research study completed recently at the University of Illinois focused on identifying the major causes of this differential movement and implementing suitable rehabilitation measures to mitigate recurrent problems with settlement and geometry. Transient and permanent deformation trends were observed in track substructure layers at two instrumented Bridge Approaches along the Amtrak Northeast Corridor. Multidepth deflectometer systems installed through crossties successfully recorded both permanent (plastic) and transient deformations of individual track substructure layers. Strain gauges mounted on the rail effectively measured vertical wheel loads applied during train passage and monitored the support conditions under the instrumented crossties. Track settlement (or permanent deformation) data revealed that the ballast layer was the primary source of differential movement contributing to recurrent settlement and geometry problems. Transient layer deformations recorded under train passage were higher in the ballast than in any other substructure layer. Transient displacement and wheel load data were consistently higher at near-Bridge locations than at open-track locations. Rail-mounted strain gauges indicated that load amplification levels were significantly higher at near-Bridge locations than at open-track locations.
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application of panda and geo endoscopy techniques for improved assessment of track substructure conditions at railroad Bridge Approaches
ASME ASCE IEEE 2015 Joint Rail Conference JRC 2015, 2015Co-Authors: Debakanta Mishra, Erol Tutumluer, Jonathan Gallier, Younes Haddani, Roland GourvesAbstract:An advanced technology for measuring track substructure conditions has been developed by Sol Solution in France. This technology, referred to as the PANDA® and Geo-Endoscopy® technique, comprises driving a variable energy cone penetration device into the track substructure using an instrumented anvil to collect strength (and modulus by correlation) profile with depth. Condition monitoring of the track substructure layers is accomplished through insertion of a camera into the same hole, also called Geoendoscopy®. The tests are commonly faster than Dynamic Cone Penetration (DCP) testing and cause negligible damage to the track substructure with the use of light and portable devices. This paper presents data from PANDA® and Geo-Endoscopy® testing efforts recently carried out under the scope of an ongoing research study at the University of Illinois. The primary objective was to relate the substructure layer properties to plastic layer deformations measured through advanced geotechnical instrumentation. Combined analysis of the PANDA®, Geo-Endoscopy®, and field instrumentation data has been used to highlight the reliability of this innovative technique towards improved evaluation of track substructure layer conditions.Copyright © 2015 by ASME
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An integrated approach to dynamic analysis of railroad track transitions behavior
Transportation geotechnics, 2014Co-Authors: Debakanta Mishra, Yu Qian, Hai Huang, Erol TutumluerAbstract:Railway transitions like Bridge Approaches experience differential vertical movements due to variations in track stiffness, track damping characteristics, ballast settlement from fouling and/or degradation, as well as fill and subgrade settlement. Proper understanding of this phenomenon requires the integration of field instrumentation with analytical and numerical modeling. This paper introduces an integrated approach to dynamic analysis of the railway track transitions behavior using field instrumentation, analytical modeling, as well as numerical simulations using the Discrete Element Method (DEM). Several Bridge Approaches have been instrumented to monitor the track response on a problematic portion of the US North East Corridor (NEC), which is primarily a high-speed railway line with occasional freight traffic, carrying high-speed passenger trains operating up to a maximum speed of 241 km/h. Previous publications by the authors have focused on findings from geotechnical instrumentation of railroad track transitions, as well as the validity of a fully coupled 3-dimensional track dynamic model and image-aided discrete element models. The primary contribution of the current manuscript involves the combination of these three components to propose an integrated approach for studying the behavior of railroad track transitions. Track response data from instrumented Bridge Approaches were used to determine track substructure layer properties and calibrate a fully coupled 3-dimensional track dynamic model. Loading profiles generated from this model were then used as input for a discrete element based program to predict individual particle accelerations within the ballast layer. The importance of modeling the ballast layer as a particulate medium has been highlighted, and the particle to particle nature of load transfer within the ballast layer has been demonstrated.
David D. Davis - One of the best experts on this subject based on the ideXlab platform.
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ballast settlement ramp to mitigate differential settlement in a Bridge transition zone
Transportation Research Record, 2015Co-Authors: Yu Qian, Youssef M A Hashash, Jamshid Ghaboussi, Erol Tutumluer, David D. DavisAbstract:Differential settlement in railroad track transitions, often associated with differences in track stiffness, may apply considerable impact load and may cause rapid deterioration of track geometry. Such differential settlement commonly seen in Bridge Approaches may lead to problems in ride comfort, track safety, and reliability. Ballast and subballast layers have been identified as a major cause of differential settlement related to the particulate nature of the aggregate deformation behavior causing degradation and breakdown associated with increased track usage. This paper describes an innovative field approach that successfully demonstrated the use of engineered ballast materials for reducing or mitigating the differential settlement problem in a Bridge transition zone. Discrete element method (DEM) simulations were used to predict full-scale track deformations of four ballast materials having different gradations and aggregate shape properties. An imaging device was used to create accurate particle siz...
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evaluation of a track transition design for soft subgrade Bridge Approaches
Railway track and structures, 2010Co-Authors: David D. Davis, Rafael Jimenez, Joseph Lopresti, Jeanlouis Briaud, Jennifer NicksAbstract:Track transitions, areas where the track structure changes, such as at Bridges or road crossings, are problem areas for track maintainers and can become chronic maintenance areas. The dynamic and long-term performance of these transition zones can vary from the surrounding track, resulting in differential settlement that produces track surface and alignment defects. While it is unlikely to eliminate changes in track stiffness, damping, or long-term settlement across transitions, it may be possible to provide adequate transitions, smoothly ramping from one track structure to another. This article describes the development and testing of a prototype track section for soft subgrade Bridge Approaches in order to ease problems for track maintainers.
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Track Differential Settlement Model
ASME IEEE 2007 Joint Rail Conference and Internal Combustion Engine Division Spring Technical Conference, 2007Co-Authors: David D. Davis, Steven M. ChrismerAbstract:A study of track settlement behavior at critical transitions such as road crossings and Bridge Approaches has yielded a model to predict the amount of differential track settlement at these transitions caused by ballast and subgrade deformation. This AAR ballast and subgrade deformation model has been developed from field and laboratory test data, and has been validated with field settlement measurements at Bridge Approaches where the ballast and subgrade properties were well documented. As an analytical tool the model can determine the rate of track differential settlement at transitions with traffic loading and to predict when tamping is required to correct track geometry. Also the model can determine the relative amount of deformation from the individual ballast and subgrade layers. These capabilities provide a means to assess whether the main source of deformation is the subgrade or the ballast and the best means to reduce differential settlement and decrease the frequency of tamping at these track transitions.© 2007 ASME
Ilyess Ksouri - One of the best experts on this subject based on the ideXlab platform.
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Evaluation and Recommendations for Flowfill and Mechanically Stabilized Earth Bridge Approaches
Transportation Research Record, 2008Co-Authors: Naser Abu-hejleh, Dennis Hanneman, Trever Wang, Ilyess KsouriAbstract:To alleviate the common Bridge bump problem, the Colorado Department of Transportation (CDOT) has employed three new alternatives for Bridge abutment backfill since 1992: flowfill, mechanically stabilized earth (MSE) using well-graded granular Class 1 backfill (reinforced soil mass as in MSE walls), and MSE using free-draining Class B filter material. However, the occurrence of Bridge bump problems is still reported. A study evaluated CDOT current practice for design and construction of Bridge Approaches and then developed recommendations to improve this practice (improve performance and reduce costs) on the basis of the results of the following: (a) best practices for Bridge Approaches collected from CDOT staff and reported in the literature, (b) evaluation of the performance and cost-effectiveness of Colorado's MSE and flowfill Bridge Approaches, and (c) identification of the causes of significant Bridge approach settlement problems observed in some of Colorado's MSE and flowfill Bridge Approaches. Eval...
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Evaluation and Recommendations for Flowfill and Mechanically Stabilized Earth Bridge Approaches
Transportation Research Record: Journal of the Transportation Research Board, 2008Co-Authors: Naser Abu-hejleh, Dennis Hanneman, Trever Wang, Ilyess KsouriAbstract:To alleviate the common Bridge bump problem, the Colorado Department of Transportation (CDOT) has employed three new alternatives for Bridge abutment backfill since 1992: flowfill, mechanically stabilized earth (MSE) using well-graded granular Class 1 backfill (reinforced soil mass as in MSE walls), and MSE using free-draining Class B filter material. However, the occurrence of Bridge bump problems is still reported. A study evaluated CDOT current practice for design and construction of Bridge Approaches and then developed recommendations to improve this practice (improve performance and reduce costs) on the basis of the results of the following: (a) best practices for Bridge Approaches collected from CDOT staff and reported in the literature, (b) evaluation of the performance and cost-effectiveness of Colorado's MSE and flowfill Bridge Approaches, and (c) identification of the causes of significant Bridge approach settlement problems observed in some of Colorado's MSE and flowfill Bridge Approaches. Evaluation procedures and forensic investigations were developed and applied to obtain the information needed for the first two items. Flowfill should remain a viable alternative for certain field and construction scenarios that justify its higher costs. MSE Approaches with both Class B and Class 1 backfill materials should be routinely used in future CDOT projects with documentation of their performance and cost (construction and repair costs) for a future evaluation. Comprehensive recommendations are presented to mitigate the observed Bridge approach settlement problem; the most important recommendations are for improved support and drainage systems for the sleeper slab where the settlement problem occurs.
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Flowfill and MSE Bridge Approaches: Performance, Cost, and Recommendations for Improvements
2006Co-Authors: Naser Abu-hejleh, Dennis Hanneman, Trever Wang, David J White, Ilyess KsouriAbstract:Construction of a typical Colorado Department of Transportation (CDOT) Bridge approach structure includes placement of a high quality backfill material behind the abutment wall, and installation of a concrete approach slab supported by the Bridge abutment wall at one end and the sleeper slab foundation at the roadway end. Since 1992, three new alternatives for the abutment backfill have been employed by CDOT: (1) relatively expensive flowfill; (2) lower cost mechanically stabilized earth (MSE) using granular, well-graded Class-1 Backfill, and (3) MSE using free draining Class B Filter soil. However, Bridge bump problems at the sleeper slab are still occurring. In the Founders/Meadows Bridge structure, both the Bridge footings and Approaches are supported by geosynthetic-reinforced soil (GRS) walls to minimize the uneven settlements between the Bridge and its Approaches (called "GRS Abutment"). Since this structure is unique, performance data from gauges embedded in the Approaches and from smoothness tests were collected over five years. The objective of this study is to improve CDOT's current practice for Bridge Approaches (improve performance and reduce costs) based on the following information obtained in this study: (1) comments and suggestions collected from CDOT Staff and reported in the literature; (2) performance and cost-effectiveness of CDOT's MSE and flowfill Bridge Approaches and performance and design assessment of the Founders/Meadows GRS Approaches; and (3) causes and sources of the Bridge approach settlement problems observed in some of CDOT's MSE and flowfill Bridge Approaches.
Yu Qian - One of the best experts on this subject based on the ideXlab platform.
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ballast settlement ramp to mitigate differential settlement in a Bridge transition zone
Transportation Research Record, 2015Co-Authors: Yu Qian, Youssef M A Hashash, Jamshid Ghaboussi, Erol Tutumluer, David D. DavisAbstract:Differential settlement in railroad track transitions, often associated with differences in track stiffness, may apply considerable impact load and may cause rapid deterioration of track geometry. Such differential settlement commonly seen in Bridge Approaches may lead to problems in ride comfort, track safety, and reliability. Ballast and subballast layers have been identified as a major cause of differential settlement related to the particulate nature of the aggregate deformation behavior causing degradation and breakdown associated with increased track usage. This paper describes an innovative field approach that successfully demonstrated the use of engineered ballast materials for reducing or mitigating the differential settlement problem in a Bridge transition zone. Discrete element method (DEM) simulations were used to predict full-scale track deformations of four ballast materials having different gradations and aggregate shape properties. An imaging device was used to create accurate particle siz...
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An integrated approach to dynamic analysis of railroad track transitions behavior
Transportation geotechnics, 2014Co-Authors: Debakanta Mishra, Yu Qian, Hai Huang, Erol TutumluerAbstract:Railway transitions like Bridge Approaches experience differential vertical movements due to variations in track stiffness, track damping characteristics, ballast settlement from fouling and/or degradation, as well as fill and subgrade settlement. Proper understanding of this phenomenon requires the integration of field instrumentation with analytical and numerical modeling. This paper introduces an integrated approach to dynamic analysis of the railway track transitions behavior using field instrumentation, analytical modeling, as well as numerical simulations using the Discrete Element Method (DEM). Several Bridge Approaches have been instrumented to monitor the track response on a problematic portion of the US North East Corridor (NEC), which is primarily a high-speed railway line with occasional freight traffic, carrying high-speed passenger trains operating up to a maximum speed of 241 km/h. Previous publications by the authors have focused on findings from geotechnical instrumentation of railroad track transitions, as well as the validity of a fully coupled 3-dimensional track dynamic model and image-aided discrete element models. The primary contribution of the current manuscript involves the combination of these three components to propose an integrated approach for studying the behavior of railroad track transitions. Track response data from instrumented Bridge Approaches were used to determine track substructure layer properties and calibrate a fully coupled 3-dimensional track dynamic model. Loading profiles generated from this model were then used as input for a discrete element based program to predict individual particle accelerations within the ballast layer. The importance of modeling the ballast layer as a particulate medium has been highlighted, and the particle to particle nature of load transfer within the ballast layer has been demonstrated.