BRITTLE FAILURE OF TIMBER STRUCTURES UNDER CONSIDERATION OF UNCERTAIN DATA

摘要

The paper is concerned with the numerical simulation of wooden structures by means of the Finite Elements Method. Thereby, the elastic properties are described by a cylindrically anisotropic model [8, 9]. The main focus of this contribution is on the modelling of brittle failure as a result of tension and shear loading, especially perpendicular to grain, which leads to crack formation. To consider this behavior in the numerical simulation, cohesive elements, referred to as interface-elements, are applied to model discrete cracks [3, 6]. The cohesive elements are inserted between the faces of continuum elements. Therefore, the model is mesh dependent, in the sense that crack propagation is only possible along edges of continuum elements. This is not a disadvantage considering wood. Due to its anisotropy, wood predefines possible crack planes. The interface-elements introduced here (Figure 1) are inserted in known or at least assumed crack planes before numerical simulation.