Evaluation of short-term ageing influence on the properties of sbs elastomer modified road bitumens
Mieczysław Słowik
, Przemysław Adamczak
Abstract
The paper presents selected rheological properties of bituminous binders aged by using various laboratory procedures. Samples of 50/70 penetration grade road bitumen pure as well as modified with SBS elastomer addition of amount 3%, 5% and 7% (by mass) have been investigated. The short-term ageing of the bituminous binders has been simulated by making use three selected laboratory methods: TFOT (Thin Film Oven Test), RTFOT (Rolling Thin Film Oven Test), TFOTmod (modified TFOT method). A short-term ageing influence on modified bitumens behavior has been assessed analyzing changes in their consistency, temperature susceptibility, and rheological properties – viscosity and elasticity, that were observed as effect of ageing process simulated in the laboratory by using each method. The analysis of test results has been focused in changes in behavior of the investigated bituminous binders caused by ageing simulated using various laboratory methods, as well as the influence of modifier (SBS elastomer) content on the behavior of aged binders. The analysis of the results showed a large diversity of resistance to ageing of the tested binders, that depends on the SBS copolymer content. The significant difference in behavior of the binders aged using various methods has been observed.