Determination of the strength properties of wood in the inspection of buildings and structures: methods, problems and solutions

The paper considers the ways and methods of determining the strength of wood according to the current norms and rules. The required number of wood samples are tested and compared with the strength characteristics in SP 64.13330.2020 “Wood structures”. It is concluded that it is impossible to use the obtained results for calculations of building structures, due to the lack of coefficients in the norms, taking into account the vices of wood and the scale factor. The existing methods of nondestructive control of wood were analyzed. The tests were carried out and the dependences between the speed of sound along and across the fibers and the strength of the samples were plotted. The conclusions about the possibility of using the ultrasonic method to determine the strength of wood in the examination of buildings are made.