A Simplified Method for Determination of the Moisture Transfer Coefficient of Concrete

The moisture transfer coefficient (MTC) is an important parameter utilized in modeling of moisture ingress into concrete. Test methods for estimating the MTC are generally performed using time-consuming combined experimental-numerical procedures. This paper presents a simple and practical method for the determination of the MTC using only water absorption test results. In this regard, a comprehensive nomograph was constructed based on finite element (FE) analysis of moisture transfer which relates the MTC to the water absorption measurements of concrete specimens. To validate the proposed method, eight concrete mixtures were prepared and their MTCs were obtained using the proposed nomograph and water absorption measurements after 1 and 4 h of immersion. Using the estimated MTCs, a numerical model was applied to predict the water absorption. The subsequent water absorption data resulting from the FE model were compared with the laboratory test results at intervals of 8, 12, 24 and 72 h, with h standing for "hour". An observed error level up to 5% confirmed the validity of the proposed method.