Stress waves tomography for the analysis of structural timber: limits, applications, possible combinations with other analysis techniques

The application of acoustic tomography for timber inspection is discussed in the paper. Combination with other methods, to support data interpretation is suggested. Stress wave tomography, based on time-of-flight measurement, has been used for imaging strength affecting heterogeneities in wood and mapping decayed areas in timber members. Complementary, images of the element faces, acquired by means of digital photogrammetry, were used to relate heterogeneities in tomograms with external indicators. Drilling resistance tests were carried out, in order to increase the “global resolution” of the analysis, in specific portions of the sections. The results suggest which factors should be taken into consideration and how complementary methods could be adopted, when acoustic tomography is used, to inspect timber elements in service.