Materiales de Construcción, Vol 61, No 301 (2011)

Assessment of the variation of the moisture content in the Pinus pinaster Ait. using the non destructive GPR technique

I. Rodríguez-Abad
Universidad Politécnica de Valencia, Spain

R. Martínez-Sala
Universidad Politécnica de Valencia, Spain

R. Capuz Lladró
Universidad Politécnica de Valencia, Spain

R. Díez Barra
Laboratorio de Estructuras. Instituto Nacional de Investigaciones Agrarias (INIA), Madrid, Spain

F. García-García
Universidad Politécnica de Valencia, Spain


The moisture content variations in wood have a significant influence in wood’s physicochemical properties, as well as in its electromagnetic properties and to specific effects upon waves’ characteristics. In particular, this paper focuses on the analysis of the Ground-penetrating Radar’s (GPR) using an antenna of 1.6GHz central frequency capacity to register the velocity and the amplitude of the electromagnetic waves’ variation during the drying process of Pinus pinaster Ait timber joists. The results showed that when timber MC descends, the propagation velocity and amplitude of both the direct and the reflected wave increased. The high correlation found between the variables studied demonstrates GPR efficiency and the innovative application of this technique as a non-destructive evaluation tool for timber structures, particularly when studying its moisture content.


Timber; Characterization; Restoration; Electric properties; Pathology

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