Time-dependent Moisture Distribution in Drying Cement Mortars – Results of Neutron Radiography and Inverse Analysis of Drying Tests

The moisture transport properties of cementitious materials may be determined by inverse analysis of easy-to-perform drying experiments. A corresponding method is proposed. It requires the measurement of the time-dependent mass loss of drying samples, includes the numerical simulation of drying, and utilizes an evolutionary optimization algorithm for identifying the moisture transport parameters. By this method, inverse analyses of drying experiments with mortar samples have been carried out whereby different physical models for the moisture transport were applied. Neutron radiographic investigations served for validating the results. The radiographically measured moisture distributions in drying samples were compared to those obtained on the basis of inverse analyses of drying experiments. It was found that different transport models which consider both vapor and liquid water transport yield almost the same results. The latter were also in good agreement with the neutron radiographic observations.