Development of Seed Variables Prediction Models for Use in Dynamic Backcalculation of FWD Data

Understanding the material properties of a pavement structure is crucial for evaluating the pavement’s performance and assessing its damage level. Generally, the backcalculation process is extensively used to analyze the Falling Weight Deflectometer (FWD)-data for estimating the layer-moduli of a pa...

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محفوظ في:
التفاصيل البيبلوغرافية
المؤلف الرئيسي: Nasr, Cynthia (author)
التنسيق: masterThesis
منشور في: 2022
الموضوعات:
الوصول للمادة أونلاين:http://hdl.handle.net/10725/13879
https://doi.org/10.26756/th.2022.391
http://libraries.lau.edu.lb/research/laur/terms-of-use/thesis.php
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author Nasr, Cynthia
author_facet Nasr, Cynthia
author_role author
dc.creator.none.fl_str_mv Nasr, Cynthia
dc.date.none.fl_str_mv 2022-07-26T10:44:23Z
2022-07-26T10:44:23Z
2022
2022-04-27
dc.identifier.none.fl_str_mv http://hdl.handle.net/10725/13879
https://doi.org/10.26756/th.2022.391
http://libraries.lau.edu.lb/research/laur/terms-of-use/thesis.php
dc.language.none.fl_str_mv en
dc.publisher.none.fl_str_mv Lebanese American University
dc.rights.*.fl_str_mv info:eu-repo/semantics/openAccess
dc.subject.none.fl_str_mv Pavements -- Performance -- Evaluation
Pavements -- Testing -- Mathematical models
Nondestructive testing
Lebanese American University -- Dissertations
Dissertations, Academic
dc.title.none.fl_str_mv Development of Seed Variables Prediction Models for Use in Dynamic Backcalculation of FWD Data
dc.type.none.fl_str_mv Thesis
info:eu-repo/semantics/publishedVersion
info:eu-repo/semantics/masterThesis
description Understanding the material properties of a pavement structure is crucial for evaluating the pavement’s performance and assessing its damage level. Generally, the backcalculation process is extensively used to analyze the Falling Weight Deflectometer (FWD)-data for estimating the layer-moduli of a pavement structure. It is mainly an iterative process that starts with a set of seed (initial) variables, calculates the theoretical pavement surface deflections, and compares them to the measured deflections. Yet, this process is most likely unstable and is prone to numerous errors including the selection of relevant seed variables. The selected seed-variables hold significant consequences on the-final backcalculated-results. This research project aims-to-develop models through classification analysis to predict the seed variables. This involves (1) calculating theoretical surface deflections through a finite element model that simulates different pavement structures and properties, (2) calculating FWD parameters and indices for each structure and (3) using those parameters to build Random Forest models that predict the seed variables with low OOB-error and high accuracy. The dynamic approach is adopted to perform the analysis on 3-layered rigid and flexible pavements. The AC layer is modeled as an LVE/material while the PCC and the unbound layers are modeled as linear/elastic materials with damping. The OOB-Estimate of error rate and the overall accuracy values obtained dictate that the predictor variables selected to build the RF models are efficiently trained and generate accurate predictions for all seed variables except for the Rayleigh Damping Parameter of the PCC layer “”. The developed models can be considered as an effective guidance for pavement engineers to select the seed variables that are closer to the actual values to initiate the backcalculation process.
eu_rights_str_mv openAccess
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id LAURepo_c4eee6a4ccc16de0cf49684293b6a4df
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network_acronym_str LAURepo
network_name_str Lebanese American University repository
oai_identifier_str oai:laur.lau.edu.lb:10725/13879
publishDate 2022
publisher.none.fl_str_mv Lebanese American University
repository.mail.fl_str_mv
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spelling Development of Seed Variables Prediction Models for Use in Dynamic Backcalculation of FWD DataNasr, CynthiaPavements -- Performance -- EvaluationPavements -- Testing -- Mathematical modelsNondestructive testingLebanese American University -- DissertationsDissertations, AcademicUnderstanding the material properties of a pavement structure is crucial for evaluating the pavement’s performance and assessing its damage level. Generally, the backcalculation process is extensively used to analyze the Falling Weight Deflectometer (FWD)-data for estimating the layer-moduli of a pavement structure. It is mainly an iterative process that starts with a set of seed (initial) variables, calculates the theoretical pavement surface deflections, and compares them to the measured deflections. Yet, this process is most likely unstable and is prone to numerous errors including the selection of relevant seed variables. The selected seed-variables hold significant consequences on the-final backcalculated-results. This research project aims-to-develop models through classification analysis to predict the seed variables. This involves (1) calculating theoretical surface deflections through a finite element model that simulates different pavement structures and properties, (2) calculating FWD parameters and indices for each structure and (3) using those parameters to build Random Forest models that predict the seed variables with low OOB-error and high accuracy. The dynamic approach is adopted to perform the analysis on 3-layered rigid and flexible pavements. The AC layer is modeled as an LVE/material while the PCC and the unbound layers are modeled as linear/elastic materials with damping. The OOB-Estimate of error rate and the overall accuracy values obtained dictate that the predictor variables selected to build the RF models are efficiently trained and generate accurate predictions for all seed variables except for the Rayleigh Damping Parameter of the PCC layer “”. The developed models can be considered as an effective guidance for pavement engineers to select the seed variables that are closer to the actual values to initiate the backcalculation process.1 online resource (xv, 169 leaves): col. ill.Includes bibliographical references (leaf 160-169)Lebanese American University2022-07-26T10:44:23Z2022-07-26T10:44:23Z20222022-04-27Thesisinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesishttp://hdl.handle.net/10725/13879https://doi.org/10.26756/th.2022.391http://libraries.lau.edu.lb/research/laur/terms-of-use/thesis.phpeninfo:eu-repo/semantics/openAccessoai:laur.lau.edu.lb:10725/138792022-08-23T06:46:48Z
spellingShingle Development of Seed Variables Prediction Models for Use in Dynamic Backcalculation of FWD Data
Nasr, Cynthia
Pavements -- Performance -- Evaluation
Pavements -- Testing -- Mathematical models
Nondestructive testing
Lebanese American University -- Dissertations
Dissertations, Academic
status_str publishedVersion
title Development of Seed Variables Prediction Models for Use in Dynamic Backcalculation of FWD Data
title_full Development of Seed Variables Prediction Models for Use in Dynamic Backcalculation of FWD Data
title_fullStr Development of Seed Variables Prediction Models for Use in Dynamic Backcalculation of FWD Data
title_full_unstemmed Development of Seed Variables Prediction Models for Use in Dynamic Backcalculation of FWD Data
title_short Development of Seed Variables Prediction Models for Use in Dynamic Backcalculation of FWD Data
title_sort Development of Seed Variables Prediction Models for Use in Dynamic Backcalculation of FWD Data
topic Pavements -- Performance -- Evaluation
Pavements -- Testing -- Mathematical models
Nondestructive testing
Lebanese American University -- Dissertations
Dissertations, Academic
url http://hdl.handle.net/10725/13879
https://doi.org/10.26756/th.2022.391
http://libraries.lau.edu.lb/research/laur/terms-of-use/thesis.php