Advanced Rail Geotechnology Ballasted Track

Ballast plays a vital role in transmitting and distributing the train wheel loads to the underlying track substructure. The load-bearing capacity, safe train speed, and the levels of noise and vibration, as well as passenger comfort depend on the behaviour of ballast through particle interlocking and the corresponding deformation of this granular assembly. Attrition and breakage of ballast occur progressively under heavy and continual cyclic loading, causing track deterioration and rail misalignment affecting safety, while exacerbating the intensity of track maintenance. In the absence of realistic computational models, the track substructure is traditionally designed using mostly empirical approaches. In this book, the authors present the detailed information on the strength, deformation, and degradation aspects of fresh and recycled ballast under monotonic, cyclic, and impact loading using innovative geotechnical testing devices. A constitutive model for ballast incorporating particle breakage is presented representing a more realistic stress–strain response. The mathematical formulations and numerical models are validated using controlled experimental simulations and fully instrumented field trials. Revised ballast gradation is described to provide greater track resiliency and extended longevity. The book also provides a detailed description of geosynthetics for substructure improvement considering track deterioration caused by particle degradation, fouling, and impeded drainage. New to this second edition are extensive discussions on subgrade soil stabilisation, causes and mechanisms of soil fluidisation (mud pumping) under cyclic loading, and preventive and remedial measures to alleviate undue instability of ballast tracks. This book should prove most beneficial for final-year civil engineering students and for postgraduate teaching and learning. It is an ideal supplement for practising railway engineers and researchers engaged in the challenging tasks of future track design for heavier and faster trains.

Ballast plays a vital role in transmitting and distributing train wheel loads to the underlying sub-ballast and subgrade. Bearing capacity of track, train speed, riding quality and passenger comfort all depend on the stability of ballast through mechanical interlocking of particles. Ballast attrition and breakage occur progressively under heavy cyc

Ballast plays a vital role in transmitting and distributing the train wheel loads to the underlying track substructure. The load-bearing capacity, safe train speed, and the levels of noise and vibration, as well as passenger comfort depend on the behaviour of ballast through particle interlocking and the corresponding deformation of this granular assembly. Attrition and breakage of ballast occur progressively under heavy and continual cyclic loading, causing track deterioration and rail misalignment affecting safety, while exacerbating the intensity of track maintenance. In the absence of realistic computational models, the track substructure is traditionally designed using mostly empirical approaches. In this book, the authors present the detailed information on the strength, deformation, and degradation aspects of fresh and recycled ballast under monotonic, cyclic, and impact loading using innovative geotechnical testing devices. A constitutive model for ballast incorporating particle breakage is presented representing a more realistic stress–strain response. The mathematical formulations and numerical models are validated using controlled experimental simulations and fully instrumented field trials. Revised ballast gradation is described to provide greater track resiliency and extended longevity. The book also provides a detailed description of geosynthetics for substructure improvement considering track deterioration caused by particle degradation, fouling, and impeded drainage. New to this second edition are extensive discussions on subgrade soil stabilisation, causes and mechanisms of soil fluidisation (mud pumping) under cyclic loading, and preventive and remedial measures to alleviate undue instability of ballast tracks. This book should prove most beneficial for final-year civil engineering students and for postgraduate teaching and learning. It is an ideal supplement for practising railway engineers and researchers engaged in the challenging tasks of future track design for heavier and faster trains.

In this book, the authors discuss testing of ballast, including the strength, deformation and degradation aspects of fresh and recycled ballast under monotonic and cyclic loading. The effectiveness of geosynthetics in stabilising recycled ballast has also been examined. A new stress-strain constitutive model for ballast incorporating particle breakage is presented. Finally, a new range of particle gradations, balancing the strength and permeability requirements, has been proposed for future rail tracks. This book is intended as a reference text for final year civil engineering students and postgraduates, and for practicing railway engineers with the task of modernizing existing designs.

This comprehensive study provides practical advice and guidance on the important topics of rail transport and ground engineering, the use of which will result in optimum quality with the minimum maintenance effort and the most economical use of resources. The authors have synthesized all of their international knowledge and experience in this field, and produced, for the first time, a definitive guide for the design, construction, maintenance and renewal of railway track as they relate to geotechnology.

Links Geotechnics with Railway Track Engineering and Railway Operation Good railway track and railway operations depend on good geotechnics, in several different ways and at varying levels. Railway Geotechnics covers track, track substructure, load environment, materials, mechanics, design, construction, measurements, and management. Illustrated by

The rail network plays an essential role in transport infrastructure worldwide. A ballasted track is commonly used for several reasons, including economic considerations, load bearing capacity, rapid drainage and ease of maintenance. Given the ever-increasing demand for trains to carry heavier axle loads at greater speeds, traditional design and construction must undergo inevitable changes for sustainable performance. Ballast is an unbounded granular assembly that displaces when subjected to repeated train loading affecting track stability. During heavy haul operations, ballast progressively deteriorates and the infiltration of fluidized fines (mud pumping) from the underlying substructure and subgrade decreases its shear strength and also impedes drainage, while increasing track deformation and associated maintenance. Features: serves as a useful guide to assist the practitioner in new track design as well as remediating existing tracks. research discussed in this book has made considerable impact on the railway industry. resulting from collaborative research between academia and industry, incorporating sophisticated laboratory tests, computational modelling and field studies. This book presents a comprehensive procedure for the design of ballasted tracks based on a rational approach that combines extensive laboratory testing, computational modelling and field measurements conducted over the past two decades. Ballast Railroad Design: SMART-UOW Approach will not only become an imperative design aid for rail practitioners, but will also be a valuable resource for postgraduate students and researchers alike in railway engineering.

This volume presents selected papers presented during the 4th International Conference on Transportation Geotechnics (ICTG). The papers address the geotechnical challenges in design, construction, maintenance, monitoring, and upgrading of roads, railways, airfields, and harbor facilities and other ground transportation infrastructure with the goal of providing safe, economic, environmental, reliable and sustainable infrastructures. This volume will be of interest to postgraduate students, academics, researchers, and consultants working in the field of civil and transport infrastructure.