Search results for "Ballast"
showing 3 items of 23 documents
EXPERIMENTAL INVESTIGATION ON DRY ASPHALT RUBBER FOR SUBBALLAST
2011
The asphalt rubber mixes have a wide application field in the railroad and road superstructures because of their technical and environmental properties. While in many countries the wet process is often used to make bituminous mixtures, the dry process doesn’t have the same degree of application even though a larger recycling of waste tires rubber is allowed than the dry process. This paper focuses on the mix-design of the Dry Asphalt Rubber (DAR) for subballast of the railroad superstructure in order to define a sound laboratory procedure of mix-design with reference to Marshall test and Superpave Gyratory Compactor (SGC) test. The comparison between Marshall test and SGC test highlights th…
Experimental Survey on Dry Asphalt Rubber Concrete for Sub-ballast Layers
2012
This paper presents the results of an experimental survey on the potential application of DARC (dry asphalt rubber concrete) in rail superstructure, within sub-ballast layers by measuring its damping and mechanical properties. Based on the environmental friendly point of view the DARC has the significant advantage as the backfill material of sub-ballast layer because the rubber comes from the waste tires of truck and its usage can results a significant recycling of non-biodegradable wastes. After a preliminary mix-design of several DARCs, with different rubber content that confirmed by using the Marshall test, the stiffness modulus and damping ratio both of a standard bituminous mixture and…
Ballasted Track Superstructures: Performance of Innovative Railway Sleepers
2012
A railway sleeper is the structural element which transversally connects the two rails by means of fastening components, thus ensuring its gauge. Its additional function is to firmly secure the track to the ballast and to distribute the loads transferred from railway carriages to the ballast. One of the most important parameters in the characterization of performance given by railway sleepers is represented by their lateral resistance to the sliding: the higher its value increases, the better the track stability becomes, thus reducing the frequency of maintenance interventions necessary to keep the superstructure efficient. This article focuses on the performance of two innovative railway s…