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The need for stable, chemical resistant and conductive materials is on the rise in recent times. Graphene shows promising electrical conductivity and chemical stability, but the production of a continual, conductive layer is limited and expensive. Silver nanowires (AgNWs) are both conducive and economically viable, but they are sensitive to water and oxygen. In this study, graphene oxide (GO) and AgNWs were synthesized and combined in different mass ratios (3:1, 2.5:1.5, and 1:1) to obtain chemically stable composites with improved electrical properties. Composites were reduced using ascorbic acid. With the increase of AgNWs to GO mass ratio, the surface of the free-standing composite film improved: the root mean square roughness was lowered from 376 nm for GO to 168 nm for the composite with the mass ratio of GO:AgNWs 1:1, while the sheet resistance was lowered from 146 x 10(6) Omega/square to 4 Omega/square. For the first time, the effects of gamma irradiation on the structure of the composites were studied. Doses of 15, 25, and 35 kGy were applied.

The fatigue resistance, as a performance indicator, is of paramount importance for the selection and benchmarking of bituminous materials. The bituminous mortar can be considered as the medium that connects and envelopes the coarse aggregate skeleton, and hence will significantly influence the fatigue resistance at bulk-scale. Therefore this study presents the steps and challenges of a new testing framework to evaluate the fatigue resistance of bituminous mortars. To do so, first, a new test geometry is introduced, which will ensure cohesive failure in a predefined area. The integrity of this sample geometry is assessed theoretically through finite element simulations and by computer tomography scans. Secondly, specimens of the new geometry are evaluated experimentally using a dynamic shear rheometer, where time-sweep tests are performed on two control mortar types under various test conditions. The control mortar types are fabricated using two commercial bituminous binders, one modified and one neat binder, to evaluate the effect of binder type. The test results are comprehensively analysed using fundamental dissipated energy-based concepts but also empirical and phenomenological failure criteria, providing insights into the failure evolution. For the tested mortar types, the analysis shows good convergence with the considered fatigue models. Finally, using dissipated energy concepts led to the most consisted fatigue model, which is independent of binder type and test conditions., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Pavement Engineering