Modeling of timber floors strengthened with seismic improvement techniques

Timber floors in existing buildings often require the adoption of stiffening techniques to improve their behaviour under horizontal actions. Modelling of such structural elements taking into account the influence of type, number and deformation capacity of the connections between beams and boards is quite complex and still under development. Starting from laboratory experimental results carried out on assemblages (sliding tests on timber-to-board connections) the paper focuses on the calibration of inelastic FE models aimed at reproducing the mechanical behaviour of floor specimens subjected to in-plane monotonic tests. Single and double boards connected with the bearing beams of the floor with nails and/or screws were examined on subassemblies. As regards floors, the effect of wood, punched steel strips or composite (CFRP or SRP) diagonals as stiffening techniques were studied. A simple parametric study including the variation of stiffness of a theoretical diagonal was performed. Results constitute a preliminary set of data that may be used for design of possible improvement techniques to be applied on existing timber floors.