Date of Final Oral Examination (Defense)
Type of Culminating Activity
Masters of Science in Civil Engineering
Debakanta Mishra, Ph.D.
Bhaskar Chittoori, Ph.D.
Arvin Farid, Ph.D.
Railway transportation has been recently gaining popularity due to its efficiency and environmental-friendly technology which has led to its increased usage for both passenger and freight transport. For railway transport to be a sustainable component of the transportation infrastructure in the United States, adequate structural and functional design of track components is essential. This is primarily dependent on thorough understanding of track mechanics and track structural response under loading, and can be accomplished through mechanistic analysis of railway track structure response under loading. Considering the need for a mechanistic track analysis program that can serve as a link between the state of art in research and state of practice in railroad engineering, one of the objectives of this research effort was to develop an advanced, easy-to-use track analysis program for use by both researchers and practitioners working in the field of railroad engineering. This was accomplished through development of a modified version of GEOTRACK (a track analysis program originally developed in the 1980's at the University of Massachusetts, Amherst), called GEOTRACK-2016 on the MATLAB® platform. GEOTRACK utilizes the principles of layered elastic analysis to predict the responses of track super- and sub-structure under vertical quasi-static loading. The first task towards the achievement of this objective involved interpretation of different elements of Layered Elastic Theory as implemented in the original version of GEOTRACK. Results produced by the new version of the software were compared with those from the original version to ensure the accuracy of all modifications. Field instrumentation data obtained from a recently completed research effort was used to constitute a `control section' for these analyses. A parametric analysis was subsequently carried out to quantify the effects of different track design parameters on overall track modulus. All results were observed to comply with the trends reported in published literature. The other objective of this Master's thesis was to evaluate the limitations introduced to analysis results when layered elastic theory is used for the analysis of in-service railroad track structures. For this purpose, a commercially available Finite Element package (ABAQUS) was used to model the control section and the track responses under loading were compared under similar loading configurations to those analyzed using GEOTRACK-2016. These comparisons revealed close match between the results and thus established GEOTRACK-2016 as an accurate, easy-to-use track analysis tool. An intuitive Graphical user Interface (GUI) was also developed for GEOTRACK-2016 to facilitate easy adoption by practicing engineers. Detailed discussions on different tasks undertaken during this research effort have been presented in this Master's thesis.
Sharma, Sadichchha, "Evaluating the Effects of Major Assumptions in Layered Elastic Theory on Railroad Track Response Prediction Through the Development of an Improved Track Analysis Software" (2016). Boise State University Theses and Dissertations. 1226.