Gas permeability of partially saturated cement-based materials considering water sensitivity

Gas permeability is a crucial factor influencing the durability of cement-based materials, which are usually in a partially saturated state. This study examines the impact of the water-to-cement (w/c) ratio, water saturation and water sensitivity on the gas permeability of cement-based materials using Nuclear Magnetic Resonance (NMR) and Mercury Intrusion Porosimetry (MIP). The results indicate that the gas permeability of cement-based materials is strongly related to their porosity and pore size distribution. Relative gas permeability is directly influenced by water saturation and the initial state of the materials, with a noticeable hysteresis effect observed. Furthermore, the water sensitivity of cement-based materials results in no evident, but a slight decrease in gas permeability during water saturation.