Search

Tire/road noise in most driving conditions dominates other sources of traffic noise. One of the most efficient ways of reducing tire/road noise is to use the so-called "low noise pavement". According to numerous studies, at present, poroelastic road pavement that is composed of rubber and mineral aggregate and polyurethane or bituminous binder gives the best noise reduction up to 12 dB. Unfortunately, there are many problems with making durable poroelastic pavements. This article presents the first results of a project that is executed in Poland and aims at the development of a durable, low noise poroelastic pavement based on polymer-modified asphalt binder called Safe, Eco-friendly POroelastic Road Surface (SEPOR). Two test sections were built in 2019 to test the production technology and performance of the SEPOR pavement. It is observed that some of the problems with previous poroelastic materials were mainly eliminated (especially delamination from the base layer and raveling) but noise reduction is a little less than expected (up to 9 dB). Rolling resistance for car tires is acceptable and fire properties (damping of spill fuel fires, toxic gas emission) are very good. [ABSTRACT FROM AUTHOR]

• Low-temperature properties of 17 asphalt mixtures and 10 bitumens were tested. • Mixtures were tested in TSRST and 3 PB and bitumen were tested in BBR and Fraass. • Multiple regression between bitumen and mixture properties were determined. • Bitumen rheological properties correspond to cryogenic stresses induced in mixture. • Mixture failure temperature results from combined bitumen properties and its content. The paper aims to identify those characteristics of bitumen which have the greatest impact on asphalt mixture low-temperature performance. It was observed that stiffness and m-value of bitumen from BBR test were moderately related to stiffness and m-value of asphalt mixture obtained from 3 PB test. Simultaneously those rheological properties significantly impact on cryogenic stresses induced during TSRST test. The multiple regression model was developed and it implied that mixture failure temperature depends both on rheological properties, brittle fracture and content of bitumen, what means that only comprehensive assessment of bitumen properties enables reasonable assessment of its low-temperature performance. [ABSTRACT FROM AUTHOR]