Predicting the density of structural timber members in service. The combine use of wood cores and drill resistance data


  • M. J. Morales-Condea Universidad de Sevilla
  • C. Rodríguez-Liñán Universidad de Sevilla
  • J. Saporiti-Machado Laboratório Nacional de Engenharia Civil



Timber, Density, Resistograh, Wood core, Structures in service, Mechanical Properties


Drilling devices is used to get information about the cross-section properties and internal defects of structural members. Drill resistance is correlated with density which is often used to predict the mechanical properties of timber elements. However in situ a regression curve cannot be obtained and pre-existent curves provides unreliable predictions. The present paper proposes a procedure for in situ “calibration” of drill resistance data. The “calibration” is based on density values from wood cores taken in the close vicinity of drill holes. Two approaches were tested. One approach based on a regression curve built using wood cores density and drill resistance values obtained from a limited number of members. The other approach uses the information of one wood core to “calibrate” the drill resistance profile taken at the same member. Following this procedure a density prediction is obtained showing a low mean percentage error and a medium coefficient of determination.


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How to Cite

Morales-Condea, M. J., Rodríguez-Liñán, C., & Saporiti-Machado, J. (2014). Predicting the density of structural timber members in service. The combine use of wood cores and drill resistance data. Materiales De Construcción, 64(315), e029.



Research Articles