Under-Tie Support Condition Assessment using Distributed Fiber Optic Strain Sensor

Overview

Project Description

This project develops a new approach for evaluating under-tie support condition using high-density strain measurements from distributed fiber-optic strain sensors (DFOSS). Because railroad tie performance is strongly influenced by the uniformity of support beneath the tie, accurately characterizing support distribution is essential for understanding tie behavior and preventing premature deterioration. The study combines dense strain sensing with an inverse analysis framework based on beam theory to reconstruct bending moment, shear force, and support force distribution along the tie. Experimental results showed that the method can accurately identify different support conditions and capture support non-uniformity more effectively than conventional discrete sensing approaches. The project demonstrates the potential of distributed fiber-optic sensing for improving track condition assessment, advancing support characterization, and providing a more reliable basis for railroad tie evaluation and maintenance.