Open AccessAnalysis of the bearing capacity of unbound granular mixtures with rubber particles from scrap tyres when used as sub-ballast
Author(s) -
Carlos Hidalgo Signes,
Pablo Martínez Fernández,
Julio Garzón-Roca,
Ricardo Insa
Publication year - 2016
Publication title -
materiales de construcción
Language(s) - English
Resource type - Journals
eISSN - 1988-3226
pISSN - 0465-2746
DOI - 10.3989/mc.2016.11515
Subject(s) - scrap , ballast , natural rubber , bearing capacity , materials science , creep , subgrade , composite material , granular material , bearing (navigation) , geotechnical engineering , engineering , metallurgy , electrical engineering , cartography , geography
Scrap tyres are a problematic waste material. As a method for recycling large quantities of rubber from scrap tyres, this paper analyses the use of unbound granular mixtures with varying percentages of rubber particles as sub-ballast in railway lines. Bearing capacity for such mixtures is studied in laboratory and field tests using static and dynamic plate load tests, as well as cyclic triaxial tests. It is found that adding rubber increases permanent and resilient strain and that none of the mixtures suffer plastic creep after 2.5 million cycles. Considering the usual bearing capacity requirements, the optimum rubber content is 2.5% (by weight). This percentage increases resistance to degradation while ensuring sufficient bearing capacity