Integrated approach to predict deterioration of mechanical properties of decaying wood

The aim of this paper is to present a methodology to predict bending or compression resistance of structural wooden elements during the onset and growth of the material decay. Two methods are proposed to calculate remaining bending and compression resistance under the attack of brown rot and white rot are presented: (1) reduction of material strength or (2) reduction of the cross-section of the wooden element. The methods are based on the bending and compression tests of material exposed to extreme moisture and are demonstrated as a part of the structural integrity online calculation tool introduced in this paper. They are applicable to planed wood where the decay is expected to progress from the surface inwards. It should be noted that the prediction of structural resistance is in the present state limited to specific loading conditions and decay mechanisms and it is not recommended to replace structural design according to the building codes. However, the estimation of the remaining structural integrity of the material may be very important for the planning of maintenance actions in the structures, such as bridges, where the immediate replacement is not possible or for better safety measures in removing, renovating or demolishing decaying wooden construction.