Print Email Facebook Twitter Rejection and Correction of the Fracture Mechanics Singularity Approach with its Associated Tree Modes of Crack Separation Title Rejection and Correction of the Fracture Mechanics Singularity Approach with its Associated Tree Modes of Crack Separation Author van der Put, T.A.C.M. (TU Delft Bio-based Structures & Materials) Date 2018 Abstract Limit Analysis is an prescribed exact approach of Wood Science, what is shown to also apply for wood Fracture Mechanics. Knowledge of the gradual elastic to plastic behavior and of the imitation by non-linear elasticity (and J-integral) is shown to be not needed. The linear – full plastic limit approach delivers an elastic lower bound, up to this full plastic boundary, the fracture- or yield criterion, where ultimate load behavior is described, by virtual work approach and “flow” by the normality rule. This delivers the possibility to look at any equilibrium system, which satisfies compatibility and boundary conditions and nowhere exceeds this “flow” criterion and is verified by test data. Because the accepted singularity approach does not deliver a right mixed mode fracture criterion, it is necessary to make comparisons with other possible Airy stress functions. Therefore, the derivation of the accepted, general applied, elementary singularity solution with its 3 failure modes, is discussed and compared with new theory. This new limit analysis theory is based on an older, forgotten, Airy stress function, and shows e.g., by the new approach and application to wood, that there is no real difference between strength theory and fracture mechanics and between linear and non-linear theory. It delivers the, empirical verified, exact mixed mode failure criterion for wood; shows that stresses in the isotropic wood matrix also have to be regarded separately, to explain the, only by isotropy, possible, extremely high triaxial hydrostatic stress, and stress increase by the stress spreading effect. To reference this document use: http://resolver.tudelft.nl/uuid:70ac2f35-d2fd-4a18-9927-d49e53f5be37 ISSN 2466-4308 Source Open Science Journal Part of collection Institutional Repository Document type journal article Rights © 2018 T.A.C.M. van der Put Files PDF Rejection_and_correction_ ... ation_.pdf 2.69 MB Close viewer /islandora/object/uuid:70ac2f35-d2fd-4a18-9927-d49e53f5be37/datastream/OBJ/view