Degree Name

Doctor of Philosophy


School of Civil, Mining and Environmental Engineering


Railway is one of the prominent transportation modes in terms of bulk passenger and freight movements. Rapid population growth and high demand for mobility have necessitated the high-speed heavy haul trains to improve productivity and efficiency. Ballast, the most common foundation material of railways is subjected to inevitable plastic deformation, densification, particle degradation and fouling owing to large cyclic and impact load generated by fast-moving heavy trains. This critically hampers the safety and efficiency of tracks by enforcing speed restrictions and track closure for more frequent track maintenance. This problem is more critical in the ballasted track on stiff subgrades like bridges and tunnel etc.

One of the promising approaches is to stabilise ballasted track using rubber mats (Under Sleeper Pads-USP and Under Ballast Mats- UBM), with the aim of absorbing energy and reducing particle breakage to improve track stability, longevity and safety. USP and UBM are widely applied in railways in the last few decades for noise and vibration attenuation purposes, and there is a notable lack of comprehensive study in geotechnical perspective. This study presents the current state-of-the-art knowledge of the use of Under Sleeper Pads (USP) in ballasted track acquired through large scale laboratory testing, and computational modelling conducted at the University of Wollongong (UOW).

In this research, the cyclic load inserted on track by heavy haul trains were simulated in the laboratory using the process simulation primordial triaxial apparatus (PSPTA)...

This thesis is unavailable until Wednesday, March 03, 2021



Unless otherwise indicated, the views expressed in this thesis are those of the author and do not necessarily represent the views of the University of Wollongong.