Quantitative analysis of quartz deformation affecting ASR in concrete

During the last two decades, an increasing number of constructions affected by alkali-silica reaction (ASR) was found. In the Czech Republic, ASR was characterized deteriorating concrete pavements, airports, bridges, and dams. One of the arguments for the frequent occurrence of ASR damage is regarded to be in extensive use of quartz-rich aggregates in concrete and an insufficient knowledge of the parameters affecting their ASR. The project submitted proposes to measure the ASR of quartz-rich aggregates, employing chemical methods and an accelerated mortar bar test combined with acoustic emission analysis. Quartz crystallinity and deformation will be characterised quantitatively employing microscopic methods (SEM/EDS, CL, TEM, and FTIR). The approach mentioned above will enable the finding of those parameters responsible for the ASR of quartz. The project results will be published in scientific journals, and conferences. Their applications in the technical regulations concerning aggregate testing will contribute to the mitigation of ASR in new constructions in the Czech Republic.