Search results for " dry asphalt rubber"
showing 5 items of 5 documents
THE RESISTANCE TO FATIGUE OF DRY ASPHALT RUBBER CONCRETE FOR SUB-BALLAST LAYER
2015
The more and more frequent use of recycled materials within the road and railway infrastructures is now an irreversible trend. In this area the use of Dry Asphalt Rubber Concrete (DARC) in sub-ballast layer seems to be a suitable technique to reach high mechanical and environmental performance even if such material should be analyzed over a long time horizon. This paper presents the results of experimental research focused on the resistance to fatigue of Dry Asphalt Rubber Concrete in sub-ballast layers; the survey has been carried out using four-point bending test (4pbt) on mixture samples with different rubber contents. The results of fatigue in DARC have been compared with the performanc…
Mechanical characterization of dry asphalt rubber concrete for base layers by means of the four bending points tests
2012
The mechanical characterisation of the asphalt concrete in terms of both the fatigue resistance and the stiffness modulus is necessary to use any design method of the flexible road pavements. Even more the determination of these mechanical properties is necessary if the asphalt concrete investigated is an innovative material as a dry asphalt rubber concrete DARC (i.e. a bituminous mixture with rubber via dry process). Such material is less known and investigated than the asphalt rubber concrete via wet process, even if its application implies peculiar economical and environmental advantages such as no specialized equipment or significant plant modifications and large quantity of recycled wa…
Experimental Survey on Dry Asphalt Rubber Concrete for Sub-ballast Layers
2012
The railway traffic through a town or near built-up areas causes heavy effects such as noise and vibration on surroundings. In order to minimize the level of these impacts the railway companies with researchers and practitioners seek suitable solutions especially in the field of the rail-track because the main source of the ground borne vibrations and noise is the bad wheel-track contact. In particular, a big effort is addressed to new materials with high mechanical and environmental performance that can be utilized within the sub-ballast layer. This paper presents the results of an experimental survey on the potential application of Dry Asphalt Rubber Concrete (DARC) in sub-ballast layers …
DAMPING AND MECHANICAL PROPERTIES OF DRY ASPHALT RUBBER FOR SUB-BALLAST LAYERS
2011
The passage of railway lines through a town or near built-up areas poses serious environmental problems such as noise and vibration. Consequently railway companies have shown an increasing interest in developing new materials with high mechanical and environmental performance. This paper presents the results of an experimental research on the potential application of Dry Asphalt Rubber (DAR) in sub-ballast layers by measuring its damping and mechanical properties. An experimental survey based on four point bending and Marshall tests was carried to measure the stiffness modulus and damping ratio both of a standard bituminous mixture and of dry asphalt rubber mixture with a rubber content equ…
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…