POLYMER-MODIFIED ASPHALT PROPERTIES RELATED TO ASPHALT CONCRETE PERFORMANCE.

Mechanical properties of asphalts containing styrenic block copolymers and properties of dense-graded asphalt concrete produced from these binders are presented. Materials studied include unmodified AC-5 and AC-20 asphalts and AC-5 containing 3 and 6% styrenic block copolymers. Dynamic rheology of the binders is studied as a function of temperature and deformation rate. Complex viscosity of the polymer-modified asphalts exhibits less temperature susceptibility than that of control asphalts from 0 degree C (32 degree F) to 93 degree C (200 degree F) and slightly higher temperature susceptibility above 93 degree C (200 degree F). The modified asphalts are viscoelastic throughout the pavement operating temperature range with a significant elastic component. However, the unmodified asphalts are essentially nonelastic above 38 degree C (100 degree F). Increases in polymer content increase viscosity, ductility, toughness, tenacity, and elasticity of the materials tested. Asphalt concrete is evaluated by resilient modulus and indirect tension over a range of temperatures.

Duke Scholars

Author John P. Kirkpatrick Radiation Oncology