Issue 31

C.L. dos Santos et alii, Frattura ed Integrità Strutturale, 31 (2015) 23-37; DOI: 10.3221/IGF-ESIS.31.03 23 Mechanical behaviour of wood T-joints. Experimental and numerical investigation C.L. dos Santos, J.J.L. Morais Engineering Department, School of Science and Technology, University of Trás-os-Montes e Alto Douro, Quinta de Prados, 5000- 801 Vila Real, Portugal University of Trás-os-Montes e Alto Douro, CITAB, Quinta de Prados, 5000-801 Vila Real, Portugal clsantos@utad.pt A.M.P. de Jesus Engineering Department, School of Science and Technology, University of Trás-os-Montes e Alto Douro, Quinta de Prados, 5000- 801 Vila Real, Portugal IDMEC, Pólo-FEUP, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal A BSTRACT . Results of a double-shear single-dowel wood connection tested under monotonic quasi-static compression loading are presented and discussed in this paper. The wood used in this study was a pine wood, namely the Pinus pinaster species, which is one of the most important Portuguese species. Each connection (specimen) consists of three wood members: a centre member, loaded in compression along the parallel-to- grain direction and two simply supported side members, loaded along the perpendicular-to-grain direction (T- connection). The load transfer between wood members was assured by means of a steel dowel, which is representative of the most common joining technique applied for structural details in wooden structures. The complete load-slip behaviour of the joint is obtained until failure. In particular, the values of the stiffness, the ultimate loads and the ductility were evaluated. Additionally, this investigation proposed non-linear 3D finite element models to simulate the T-joint behaviour. The interaction between the dowel and the wood members was simulated using contact finite elements. A plasticity model, based on Hill’s criterion, was used to simulate the joint ductility and cohesive damage modelling was applied to simulate the brittle failure modes (splitting) observed in the side members of the joint. The simulation procedure allowed a satisfactory description of the non-linear behaviour of the T-joint including the collapse prediction. K EYWORDS . Maritime pine wood ( Pinus pinaster Ait.); Dowel-type connections; T-connections; Finite Element Analysis; Hill Plasticity model; Cohesive damage models. I NTRODUCTION he connections are frequently the critical elements of timber structures, being responsible for the reduction of continuity and global structural strength, requiring oversized structural elements. About 80% of failures observed in timber structures are due to connections [1]. Dowel-type timber connections are the most common T