Alkali-silica reaction – a multidisciplinary approach

In the last four years, a multidisciplinary study involving several research groups in Switzerland tackled number of unsolved, fundamental issues about alkali-silica reaction (ASR) concrete. The covered topics include SiO2 dissolution, characterization various ASR products formed at different stages both concrete and synthesis, crack formation propagation. encompassed scale ranges from nanometers to meters. Apart conventional techniques, novel methods for field have been used, e.g. combination scanning electron microscopy with dissolution experiments, focused ion beam transmission microscopy, synchrotron-based methods, synthesis in-depth characterization, time-lapse X-ray micro-tomography combined contrast-enhancing measures numerical models damage based on realistic patterns. Key achievements findings are quantification effect aluminum silicates, variance morphology composition initial products, differences similarities between amorphous calcium-silicate-hydrate, link temperature structure crystalline behavior varying relative humidity, propagation 4D modelling