Moisture ingress in cracked cementitious materials

Wedge split test specimens were conditioned to a relative humidity of 50%, deformed to various damage states, and exposed to liquid water. Water ingress was monitored using x-ray attenuation measurements and compared to numerical predictions. The transport model accounts for the damage state using the cracked hinge model and a simplified approach whereby a crack is considered to consist of two distinct parts: 1) a coalesced crack behaving as a free surface for moisture ingress, and 2) an area of isolated micro cracks behaving as bulk material.

Comparison of experimental and model results shows the simplified crack geometry approach applied in the transport model is capable of predicting the ingress of moisture and influence of cracks. The model was found to underestimate the vertical extent of moisture ingress in the largest CMOD samples (0.20 and 0.40 mm), which was likely due to instability of the large cracks in these samples.