Quantitative analysis of saline transport and crystallization damage in porous limestone visualized by neutron and X-ray imaging

This article presents coupled data on saline transport, pore filling due to salt crystallization and resulting salt damage in Savonnières limestone. This is achieved by combining the non-destructive techniques of neutron radiography - for transport imaging - and X-ray microtomography - for pore structure and fracture visualization -- applied to the same sample when subjecting it to consecutive wetting-drying cycles. Capillary uptake of water, 1.4m sodium sulfate and 5.8m sodium chloride solutions is studied at 25textdegreeC. An important decrease of the penetration coefficient for the salt solutions compared to water is found. Halite crystallization fronts are located based on neutron radiographs of the dried samples. Porosity analysis of the X-ray tomographic datasets quantifies pore filling at the position of the crystallization front. The damaging character of the salts is assessed from these datasets too. Only the sodium chloride wetted samples show fractures under the specific test conditions used (drying at 40textdegreeC).