Assessment of the Lateral Bearing Capacity of Traditional Walls Made of Timber Planks

Evaluation of the structural capacity of existing buildings is a key component in the seismic risk assessment process to estimate damage and socioeconomic losses due to earthquakes. In Eastern Canada, a large number of traditional residential buildings were built between 1860 and 1915 using a mixed structural system of unreinforced masonry «URM» and wood. The lateral stability and resistance of several of those traditional buildings rely on the behaviour of the peripheral walls made of timber planks covered by a brick veneer. These traditional walls, called “carrés de madriers”, are composed of timber planks, stacked horizontally between two wood posts delimiting panels between the wall openings. The lateral resistance is provided by the interaction and friction mechanisms between the horizontal timber planks and their interaction with the vertical wood posts. The main objective of this paper is to present: (1) a structural and mechanical characterization of a typical wall and (2) an evaluation of the lateral capacity using an analytical model and a finite element (FE) model. The analytical model is derived from the literature and used to estimate the maximum lateral displacement/resistance for this type of walls when subjected to in-plane lateral forces. In addition, major outcomes of a FE numerical investigation carried out on a single wood panel with the software ABAQUS© are discussed for different loading conditions (i.e. in-plane lateral and vertical compressive loads). Recommendations are given to improve the FE model especially the modelling of the connections between the horizontal and vertical elements.