INFLUENCE OF ACCELERATED AGEING ON PULL-OFF STRENGTH OF CONCRETE PRODUCED WITH RECYCLED CONCRETE AGGREGATE AND BLENDED WITH HEMP FIBRES

Abstract

As a result of increased demand for non-renewable raw resources, high energy consumption,and, most significantly, negative environmental repercussions, the construction sector is transitioning toward environmentally friendly products. Some feasible options for developing alternative low-cost, renewable and green materials include the utilization of natural fibres and recycled materials from construction and demolition (C&D) waste. This report summarizes a portion of the experimental research being conducted as part of a bilateral research project: ''BIO-based cementitious composites with recycled aggregates (Bio-gates),'' performed by teams from Novi Sad's Faculty of Technical Sciences and Vienna's Technical University. The study focuses on the effects of hemp fibres and recycled concrete aggregate (RCA) on the pull off strength of concrete, cured under normal conditions and subjected to wet/dry cycles (accelerated ageing regime). The obtained results revealed that RCA has no detrimental effect on the adhesive bond, while hemp fibres reduce the pull off strength of concrete to a greater extent. Nonetheless, adhesion to the substrate might be considered acceptable for all tested concrete types when the limit values specified in the applicable regulations are taken into account.