Waste tyres are abundantly available, and if utilised in large volumes can contribute to sustainable development and an environmentally friendly secondary aggregate option. Research in the use of waste tyre in the form of crumb rubber and powder obtained after processing, specifically for pavement engineering applications, has increased over the decades due to the engineering and mechanical properties it can bring into the pavement surfaces. These include improved durability, better service quality, and reduced noise compared to the use of tradition all primary aggregates, such as crushed rock, gravel, etc. Through years of research, the experts and researchers identified that, although, waste rubber improves the mechanical behaviour of rubberised bituminous surfaces, yet, there exist issues that need addressing. This PhD research work focuses on improving the properties of the waste tyre rubber aggregates obtained from scrap tyres for various rubberised bituminous surface applications. It identifies the issues and knowledge gap, which are related to the performance of the waste tyre aggregates in bituminous mixes and the service life of the product. However, current research has identified one of the major issues related to the interaction between the rubber and bitumen at elevated temperatures higher than 140°C. When the rubber and bitumen interacts at higher temperatures, it results in the diffusion of light fractions (maltenes, or specifically aromatic oils) from bitumen into rubber and the rubber swells by 3-5 times its original volume. The bitumen becomes hard and brittle due to the lower percentage of light fractions left compared to the heavy fractions and the rubber loses its bonding in the bituminous mixes due to the swelling which leads to breaking of the bonding and subsequently short service life of rubberised pavements. This research focuses specifically on the reduction in the absorption properties of waste rubber after its interaction with bitumen to produce highly durable material.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:572054 |
| Date | January 2012 |
| Creators | Ateeq, Muhammad |
| Publisher | Liverpool John Moores University |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
Page generated in 0.0019 seconds