Abstract
The paper presents an adapted methodology of laser holographic interferometry for an investigation of the stress-strain state of nailed timber connections. During the study the possibility of detecting local deformations in the connection were verified. The optimum conditions for fixing the samples and the loading ranges to ensure an optimal interference pattern were determined. An investigation of the peculiarities of the interaction between the elements and the stress-strain behavior of nailed timber connections was performed. The experimental data obtained on the stress-strain behavior of a nailed timber connection using the laser holographic interferometry method have sufficient repeatability between different series and can also be used as a criterion verification for a finite-element model.