Effect of Stress Singularities on Scaling of Quasibrittle Fracture
Modern engineering structures are often made of quasibrittle materials,which are brittle and heterogeneous.Typical examples include concrete,fiber composites,woven composites,tough ceramics,and nano-composites.The salient feature of quasibrittle structures is that the size of the fracture process zone is not negligible compared to the structure size,which leads to an intricate size effect on the structural strength.The current understanding of scaling of quasibrittle fracture is limited to structures with either strong stress singularities or zero stress singularities.Nevertheless,many engineering structures are designed to have complex geometries,which could cause weak stress singularities.This paper investigates the effect of stress singularities on the scaling of quasibrittle fracture both analytically and numerically.The theoretical analysis is derived from a generalized weakest link model where the energetic scaling of quasibrittle fracture is incorporated into the classical finite weakest link model.The proposed model yields a general scaling equation,which captures the transition from the energetic scaling to statistical scaling as the stress singularity gets weaker.The proposed analytical model is then verified by a numerical study on the fracture of concrete beams with a V-notch under three-point bending,where a wide range of notch angles representing different orders of stress singularities is considered.
Size Effect Deterministic Analysis Finite Weakest Link Model Quasibrittle Materials
Jia-Liang Le Mathieu Piechout Roberto Ballarini
Department of Civil Engineering,University of Minnesota,Minneapolis,55455,United States
国际会议
北京
英文
1-9
2013-06-16（万方平台首次上网日期，不代表论文的发表时间）