A heavy loaded bus lane with integrated bus stops was selected by the authorities of the city of Wuppertal to construct two test sections. In the test sections, an innovative asphalt mix (produced with high polymer modified binder) for surface and binder layer compared to conventional asphalt mix (standard bitumen) shall be paved. The innovative asphalt mixes has been used in a test section with a load cycle of 39 Mio (10 t) ESAL during a lifetime of 30 years. Same mixes with conventional asphalt were used in the second test section with a life cycle of 24 Mio (10 t) ESAL during the lifetime of 30 years. The innovative asphalt mixes have been selected by means of following asphalt tests: Conventional binder tests, elastic recovery test, performance oriented binder test (DSR), wheel-tracking test and temperature dependent resilient modules. By means of analyzing the laboratory test results, rutting was predicted by means of analytical calculations for the section with innovative asphalt mixes to a much lower extend than for the section with conventional asphalt mixes. Since reconstruction in July 2005 the rutting development has been annually measured after every summer period. After two observation periods in August 2007 the section withinnovative asphalt showed much lower rut depth (7 mm) compared to the conventional asphalt with a rut depth up to 26 mm. This development of rut depth, which have been measured in situ confirms the laboratory rutting testresults as well as the predictions.
Samenvatting