Non‐destructive testing for the analysis of moisture in the masonry arch bridge of Lubians (Spain)

The mediaeval Lubiáns bridge is evaluated in this work to detect and analyse probable moisture in masonry, which has proven to be a fundamental issue in the preservation of such historic assets, as it affects their structure. An early diagnosis is therefore required, but the detection of water content requires the use of non‐destructive techniques that do not perturb the actual state of the bridge. For the evaluation, non‐destructive assessment was considered by means of ground‐penetrating radar, photogrammetry and infrared thermography. Because of the inner heterogeneity of masonry structures, the analysis and interpretation of field ground‐penetrating radar data results complex. Sophisticated finite‐difference time‐domain modelling was therefore used to assist and to improve the interpretation of the field data. Simulations were elaborated using a mixed model of parallelization, and more realistic and large‐scale models were built from the accurate data provided by photogrammetric procedures. The interpretation of all the data acquired allowed the detection and analysis of moisture in the bridge, which can be useful information to decide subsequent conservation actions. Copyright © 2013 John Wiley & Sons, Ltd.