Abstract:
In this article, an assessment method to
estimate the residual strength of pine structural ele-
ments degraded by anobiids is presented. This novel
method was developed in the laboratory to be used
in situ and is based on the strength required to withdraw
a screw on the surface of degraded timber. Samples of
degraded maritime pine (Pinus pinaster Ait.) were
submitted to micro-computed tomography (l-XCT) to
quantify density loss. This parameter is highly corre-
lated with mechanical properties thus central for the
assessment of timber structural capacity. Density loss
values have been correlated with both screw withdrawal
force and shear parallel to the grain strength showing
significant relationships between these parameters.
Using these correlations, the density loss of a degraded
element and its shear strength parallel to the grain via
the screw withdrawal force can be estimated enabling a
valid quantitative assessment of the timber elements
residual strength and, therefore, contributing to reduce
unnecessary replacement, to boost eco-efficient inter-
ventions and to provide foundations required to perform
experimental modelling tests.