Use of rubber shreds to enhance attenuation of railway sub-ballast layers made of unbound aggregates

C Hidalgo-Signes,R Insa-Franco,J Garzón-Roca,J M Grima-Palop

doi:10.3989/mc.2017.00316

C Hidalgo-Signes, R Insa-Franco + Show 2 more

Open Access

https://doi.org/10.3989/mc.2017.00316

Copy DOI

Abstract

One of the approaches for solving the problem of induced vibrations in railways is by slightly modifying the materials that form the track. A study is presented of the attenuation capacity of mixes composed of granular soil and rubber shreds when used as sub-ballast (the layer located immediately below the ballast layer). Rubber shreds are obtained from scrap tyres, a troublesome waste material whose reuse and recycling is necessary. A series of mixes of granular soil and rubber shreds with rubber contents of between 1% and 10% are submitted to hammer impact tests to study their response to dynamic excitation. Results reveal that mixing rubber shreds with granular soil increases damping ratios, thus demonstrating the potential of the proposed mixes for attenuating vibration.

Highlights

Vibrations induced by trains are one of the main concerns addressed in the development of railways, especially when lines run through urban areas [1,2,3,4,5,6,7].Various methods such as elastic mattresses [8,9,10], open and filled trenches [11,12,13], and improved fastening systems [14] have been proposed to mitigate vibrations
This paper proposes the use of rubber shreds mixed with unbound granular materials to reduce vibrations induced by trains
In the time domain there are no significant differences between these three tests at first sight and the specimens with and without rubber shreds behave

Summary

Introduction

Vibrations induced by trains are one of the main concerns addressed in the development of railways, especially when lines run through urban areas [1,2,3,4,5,6,7] Various methods such as elastic mattresses [8,9,10], open and filled trenches [11,12,13], and improved fastening systems [14] have been proposed to mitigate vibrations. In the materials that form the track to improve performance One of these options includes the use of rubber obtained from scrap tyres. Scrap tyres can be recycled in the form of rubber shreds, obtaining a material that absorbs dynamic effects thanks to its mechanical properties. The addition of a small portion of rubber shreds is expected to enhance the dynamic performance, resulting in a new material that is promising in building and environmental terms

Methods

Results

Conclusion