Quantifying sorptivity using the contact sponge method: an improved calculation method validated by classical capillary rise experiments and neutron radiography

Abstract Non-destructive techniques such as the contact sponge method (CSM) and the Karsten tube have been developed to assess the water absorption properties of building materials during field measurements. In contrast, laboratory investigations typically rely on capillary rise tests (CR) on centimetric specimens imposing a one-dimensional water flow. Although the results obtained from these methods are qualitatively comparable, a robust quantitative correlation is still lacking. An analytical