Quantification of polymer content in binder by modified MSCR test

Abstract

The Multiple Stress Creep and Recovery Test (MSCRT) is a testing method using the dynamic shear rheometer (DSR) to determine viscoelastic and viscous binder properties in order to assess the influence on the asphalt deformation behavior. The applicability of the test conditions and the corresponding simplified evaluation method formulated in the standards are reviewed in this paper. Here, rheological analyses are performed of the creep recovery curves corresponding to the Burgers model. The results of MSCRT prove that the viscous behavior of the binder is sufficiently described under the defined test conditions. However, the viscoelastic behavior may be determined more precisely at equi-viscose temperature. Further on the modification of the test enables to assess the effectiveness of the polymers contained in the bitumen on the one hand or the polymer content on the other.

Wearing Course Mixtures Prepared with High Reclaimed Asphalt Pavement Content Modified by Rejuvenators

“…In Germany, the design process to determine the allowed RAP content, which can be included in a recycled asphalt mixture without affecting the material performance, relies on the conventional softening point ring-and-ball (SPR&B) values of the extracted RAP and virgin binders (16). The SPR&B method is commonly used to obtain the properties of asphalt binder in the high temperature domain, and in the case of routine controls (17). In addition, the SPR&B is often used in Germany by road authorities and construction companies as a key indicator for low temperature behavior, as a high SPR&B value is linked with higher binder brittleness (13).…”