Projekt BVFF - publicerade   BVFF nummer:  2015-009 Projekttitel  Development of Instrumented Indentation Test for Characterization of Rheological and Adhesive Properties of Bitumen-Based Binders and Bitumen-Filler Mastics Projektledare/Kontaktperson  Denis Jelagin Telefon  087908698 Utförarorganisation  KTH Medutförare  VTI Bakgrund  Rheological and adhesive properties of bitumen-based binders control to a great extent mixtures performance in the field, in particular with respect to its fatigue life, rutting resistance and healing characteristics. The primary goal with the project is develop experimental method for measurement of rheological and adhesive properties of bitumen and bitumen-filler mastics at different length scales. The state-of-practice testing methods for bitumen-based binders, assume them to be homogeneous linear viscoelastic materials. The characterization is than performed at a macroscopic length scale, not representative for the morphological length-scale of the binder phase in the material. Modern binders are in fact not a homogeneous material, but may contain different modifiers, such as polymers, wax or crumb rubber, dispersed into the bitumen in order to improve binder’s performance. Furthermore, several recent studies have emphasized the importance of bitumen-filler mastic properties for the asphalt mixture performance (Loorents et al. 2009). The modern binders and bitumen-filler mastics are thus scale dependent multiphase composites. In order to establish a quantitative link between the mastics mechanical and adhesive properties and the mixture performance experimental method is needed allowing characterizing mastic’s properties at length scales representative for mixture’s morphology and with material inhomogeneity taken into account. The present project aims at development of instrumented indentation testing method for characterization of bitumen and bitumen-filler mastics. Instrumented indentation testing is one of the few experimental techniques that can be performed at both large and small scales, allowing for the investigation of material behavior across length scales from milli- to nanometers. The indentation testing has a unique potential in characterizing bitumen-filler mastics properties as it can be applied to characterization of inhomogeneous materials. The present project has as it’s starting point a pre-study performed at KTH (Jelagin et al. (2013), Experimental Mechanics, 53) where technique’s feasibility to measure viscoelastic, creep and adhesive properties of bitumen has been evaluated. Furthermore, under the project the link between the measured mastics properties and asphalt mixture properties and performance will be investigated experimentally and numerically. Shear box test developed at VTI will be relied upon as primary tool for the mixture’s rheological characterization including asphalt concrete viscosity (Said et al. 2013). In order to establish explicit quantitative link between mastic’s properties and asphalt mixture behavior the X-Ray CT data-based micromechanical modelling approach developed at KTH will be relied upon. Sammanfattning  Rheological and adhesive properties of bitumen-based binders control to a great extent mixtures performance in the field, in particular with respect to its durability, fatigue life, rutting resistance and healing characteristics. Furthermore, several recent studies have emphasized the importance of bitumen-filler mastic properties for the asphalt mixture performance (Loorents et al. 2009, IJPE). The present project deals with the development of new experimental approach to measure rheological and adhesive properties of bitumen and bitumen-filler mastics. The ultimate goal of this research is to address the need for experimental tool to characterize bitumen-based mastic’s properties at length scales representative for mixture’s morphology and with material inhomogeneity taken into account. Instrumented indentation testing is one of the few experimental techniques that can be performed at both large and small scales, allowing for the investigation of material behavior across length scales. Furthermore, it has a unique potential in characterizing bitumen-filler mastics properties as it can be applied to characterization of inhomogeneous materials. The project will be performed jointly by KTH and VTI. The link between the measured mastics properties and asphalt mixture performance will be investigated with a synergetic combination of experimental and modeling tools recently developed at KTH and VTI. The main practical outcome of the project will be a new test method to characterize binders and mastics mechanical and adhesive properties at different length scales and with materials inhomogeneity taken into account. Furthermore, mastics rheological and adhesive properties are a crucial input for the asphalts performance models. Mastics parameters measured under the project will be incorporated into the asphalts permanent deformation and fracture degradation models developed at the participating research groups. Förväntat resultat  The main practical outputs of the project will be: - New test method to characterize binders and mastics mechanical and adhesive properties at different length scales and with materials inhomogeneity taken into account. - Improved understanding of the effect fillers of different petrographic types have on the bitumen-filler mastics properties and their evolution with mechanical and environmental loading. - Novel micromechanics-based model quantifying the effect of mastics properties on asphalt mixtures performance. The model will be integral part of the new cracking and rutting degradation models which will be developed at KTH under the project “Vägdimensionering - implementering av nytt ramverk”. - Mastic viscosity, in relation to the asphalt concrete viscosity, will be implemented in the mechanical models such as PEDRO model for permanent deformation in asphalt concrete layers. Plan för resultatspridning och implementering  In order to ensure that the results of the project are communicated to the research community and to the users, the following steps will be taken: - A user reference group will be formed at the start of the project. The reference group will consist of representatives of the following authorities/companies: Trafikverket (Klas Hermelin, Tomas Winnerholt), Nynas (Xiaohu Lu), PEAB (Mats Wendell). Three times a year, a detailed presentation on the project progress will be given to the reference group. In the later stages of the project Nynas intends to use the instrumented indentation technique developed in their further research on the durability of asphalt roads. - Results of the project will be published in several scientific papers and summarized in a PhD-thesis. - Results will be as well presented in national and international conferences. Tidsramar  November 2015 - November 2019. Starting date for the project may change depending on when the project is awarded