Water Stability of UHDMC

The exceptional qualities of magnesium phosphate cement-based ultra-high ductile composites (UHDMC) for repair and reinforcement are fully utilized. However, the broader use of UHDMCs is restrained due to the defective stability of magnesium phosphate cement (MPC) in wet or humid conditions. This chapter presents a sequence of tests to study the influence of factors such as curing age under ambient conditions, duration of immersion in water, water-to-binder (W/B) ratio, ratio of magnesium oxide to potassium dihydrogen phosphate (M/P), percentage of nano-Al2O3 (NA), replacement rate of fly ash (FA), and proportion of water glass (WG) on both mechanical properties and water stability of UHDMCs. A thorough examination of the core properties of UHDMCs, such as workability, resistance to compression, flexural behavior, and stability when exposed to water, is conducted. The operating mechanism explaining these effects is later exposed via Scanning Electron Microscopy (SEM).