This book considers the application of recycled materials both in pavement and geotechnical engineering. Currently, Australia has faced the fundamental concern of recycling waste plastic. On 1 January 2018, China enforced a prohibition on the importation of waste plastic. China's ban is followed by other countries like India, Indonesia, and Malaysia. The ban caused many corporations to abandon waste collection agreements, and the stockpiling of waste, as there is nowhere to safely deposit this waste. This issue seems, to a great extent, to have placed Australia's recycling industry in a crisis. As a result, local councils will have to find strategic ways of recycling accumulated waste that will become a more significant issue in the coming years. In Australia, apart from economic growth, the road pavement has weakened rapidly as the current pavement unable to withstand this urgent traffic load demand. The adding of polymers to the mixtures improves the stiffness, rutting resistance, and fatigue cracking [1]. However, the application of virgin polymer is costly. Thus, using waste polymer such as waste plastic polymer is an inexpensive substitute. The potential for recycled plastic to improve the performance properties of asphalt mixtures has been demonstrated in many countries the UK, Canada, The Netherlands, and India [2]. Similarly, another application of recycled materials can be in geotechnical infrastructure. This book considers the application of recycled materials both in pavement and geotechnical engineering. References [1] Airey, G.D., Singleton, T.M., & Collop, A.C.(2002). Properties of polymer modified bitumen after rubber- bitumen interaction. Journal of Materials in Civil Engineering .14(4), 344- 354. [2] K. O'Farrell. Australian Plastics Recycling Survey- National Report. Australian Government, Department of Environment and Energy, Australia. Project reference,2018 A21502.

The 15 papers describe field applications and laboratory testing. The topics include the geotechnics of industrial by-products; paper mill sludge for landfill cover; tire shreds as lightweight fill for embankments and retaining walls; the performance of a highway embankment and hydraulic barriers co

GSP 127 contains 15 papers highlighting the use of recycled materials in geotechnics presented in sessions of the ASCE Civil Engineering Conference and Exposition, held in Baltimore, Maryland, October 19-21, 2004.

Natural aggregates derived from a variety of source rocks have been used as a road base material. But the extraction of natural aggregates resources is increasingly being constrained by urbanization, increased costs and environmental concerns. Thus, increased amounts of reclaimed materials are being used to supplement natural aggregates in road construction. Recycled Asphalt Pavement (RAP) material is one of the important recycled materials used in the present geotechnical applications. Many agencies are constantly seeking to reap the benefits of utilizing RAP. Main advantages of utilizing RAP include the preservation of the existing profile, conservation of asphalt and aggregate resources, conservation of energy, and reduction in life-cycle cost. Therefore, it is no surprise that state highway agencies have been moving toward increasing the percentages of RAP in their HMA pavements. The 1993 EPA report mentioned that approximately 73 million tons of asphalt pavement material was recycled annually, which amounts to about 80% of the asphalt removed from pavements each year. Quarry by-products are another important recycled materials showing good performance in many geotechnical applications. These are generally obtained from crushed natural stone. One of the fines obtained from limestone stone quarries are becoming popular. These fines when they are stabilized with some cementing materials can be used in any geotechnical applications. About 159 million metric tons (175 million ton) produced annually is thought to be used in many geotechnical applications. In a recent survey, three states (Arizona, Illinois, and Missouri) indicated that quarry by-products have been used as an embankment material and three other states (Florida, Georgia, and Vermont) indicated some use of quarry by-products in base or subbase for the pavement applications. These are also used as mineral filler in asphalt paving. In this present research, a comprehensive experimental program was performed on two recycled materials which include RAP and Cemented Quarry Fines (CQF) which were used as a pavement base material. All the tests provided repeatable and reliable results. Unconfined Compressive Strength (UCS) tests showed a peak stress of 1200 kPa for the CQF which was 12 times more than the untreated sample. UCS for the RAP material showed a strength of 340 kPa which was expected for the RAP materials. Peak values for the resilient modulus for RAP and CQF were 330 MPa and 370 MPa respectively. These samples required more number of cycles to know the actual resilient modulus. Untreated sample showed a peak value of 220 MPa. Values for the swell tests was zero for the CQF whereas for the untreated sample was around 6%. RAP showed a less strain of 0.7% which is negligible for these materials. Consolidation Indices for these recycled materials showed values less than 0.001. Field monitoring data showed that the settlements and pressures were in permissible limits. Results from the experimental program along with field monitoring data showed that these recycled materials are very best suited as a pavement base material. Based on these results these recycled materials can be used for future research projects.

Design and Construction of Pavements and Rail Tracks - Geotechnical Aspects and Processed Materials is a compilation of selected contributions produced between 2002 and 2005 by the International Committee TC3 - Geotechnics of Pavements of the International Society of Soil Mechanics and Geotechnical Engineering (ISSMGE), a committee dedicated to gat