Substantially improved overlay mixes, required by the modern road industry should be highly resistent to reflection cracking. The mix must contribute significantly to the stiffness of the pavement, even when it is applied in relatively thin layers. The binder should possess a high softening temperature to reduce the sensitivity for rutting and corrugation, and it should have a reasonable penetration value to minimize the chances of cracking. In this paper attention is paid to the manner SBS polymer modified asphalt binders cope with this set of requirements. The basic principles of this modification are outlined and emphasis is laid on the rheological and mechanical properties: viscosity and penetration test results are presented. Burgers' model for viscoelastic materials is used in an attempt to describe the visco elasticy. Results of indirect tensile tests are reported, including the tensile strengths and the elastic moduli. Repeated loading tests have been done on polymer modified and plain asphaltic concrete mixes. The results are mutually compared concerning fatigue behaviour, elastic moduli and crack propagation characteristics. The paper describes various trial sections, with special attention to comparative tests carried out in an Australian accelerated loading facility.

"ASTM Publication Code Number (PCN) 04-011080-08. - "Sponsored by ASTM Committee D-4 on Road and Paving Materials."-- Foreword. - Includes bibliographical references and indexes. - Electronic reproduction; W. Conshohocken, Pa; ASTM International; 2011; Mode of access: World Wide Web; System requirements: Web browser; Access may be restricted to users at subscribing institutions.

Papers from international experts from 13 countries. Coverage includes, new developments in the theory and practice of polymer composites, studies of their performance, manufacturing techniques and the material selection process.

A five-year study has been performed to investigate the behavior of binders and asphalt mixtures containing polymer modifiers. The polymers were SBS, SBR, EVA, Ground Rubber, and polyolefin. These materials were used separately and in combinations with each other to change the characteristics of the binders and asphalt mixtures. The research included laboratory experiments to characterize the materials, and field projects to ascertain their performance. Four hot mix asphalt projects were conducted in Districts 15, 11, 25, and 10 in Texas, and two seal coat projects were constructed in Districts 6 and 17 in Texas. The testing results of the field and laboratory samples are presented in this report.

The project was designed to develop (1) a better quantitative understanding of the relation between laboratory accelerated binder aging and field aging, (2) a test procedure to measure properties of an aged binder that relate to failure on the road and (3) a proposed specification for estimating the relative durability of binders in the presence of oxidative aging. Tests were conducted on original base and polymer modified binders, laboratory compacted mixtures, and pavement aged binders. The project necessarily evolved to a more comprehensive approach to improving pavement service life.