Development of Damage Monitoring Techniques During Fatigue Compression Test on Concrete Specimen

Abstract

The current context of the climate change, exhaustion of natural resources and impetus towards circular economy is leading to an increase in the use of recycled aggregate concrete (RAC) in the construction industry. The French National Project RECYBETON investigated the feasibility of using recycled concrete aggregate (RCA) in concrete through studies of concrete’s properties, including microstructure and durability of RAC. This kind of project, transposed in the standards, allows to promote the advantages of the RCA use and an appropriate substitution rate in the concrete. Based on the previous knowledge, some characteristics of recycled concrete still require further investigation such as fatigue response. In that respect, an experimental protocol for compressive fatigue test has been developed in controlled laboratory conditions. This protocol was designed in order to monitor damage in the experimental samples during the fatigue compression test using various non-destructive methods (Ground-Penetrating Radar, modal analysis and Stiffness Damage Test). As a feasibility study, this protocol has been applied to standard concrete specimens first. The corresponding results obtained for standard concrete specimen submitted to a fatigue test are elaborated in this paper, including a comparative study of the considered non-destructive methods. This methodology not only allows to study mechanical characteristics of recycled concrete but also to monitor damage evolution over various cycles.