scholarly journals A STUDY ON MODIFIED WEIBULL STRESS BASED EVALUATION OF BRITTLE FRACTURE OCCURRENCE DURING EARTHQUAKES IN STEEL MEMBERS

2015 ◽  
Vol 71 (2) ◽  
pp. 173-185
Author(s):  
Hiroshi TAMURA ◽  
Eiichi SASAKI
Keyword(s):  
Brittle Fracture ◽  
Steel Members ◽  
Modified Weibull ◽  
Weibull Stress

Fracture Assessment of Welded Joint With Geometrical Discontinuity Using the Weibull Stress

2006 ◽  
Author(s):  
Satoshi Igi ◽  
Takahiro Kubo ◽  
Masayoshi Kurihara ◽  
Fumiyoshi Minami
Keyword(s):  
Fracture Toughness ◽  
Brittle Fracture ◽  
Welded Joint ◽  
Fracture Toughness Test ◽  
Geometrical Condition ◽  
Stress Criterion ◽  
Toughness Test ◽  
Fracture Assessment ◽  
Geometrical Discontinuity ◽  
Weibull Stress

Recently the Weibull stress is used as a fracture driving force parameter in fracture assessment. The Weibull stress is derived from a statistical analysis of local instability of micro cracks leading to brittle fracture initiation. The critical Weibull stress is expected to be a critical parameter independent of the geometrical condition of specimens. Fracture toughness test using 3-point bending and tensile tests of welded joint specimens with geometrical discontinuity were conducted in order to study the applicability of fracture assessment procedure based on Weibull stress criterion. Steel plates prepared for this study had tensile strength of 490 MPa for structural use. Two kinds of welded joint specimens, “one-bead welded joint” and “multi-pass welded joint” were prepared for fracture toughness test by using gas metal are welding. In tensile test specimen, corner flaws were introduced at the geometrical discontinuity part at where stress concentration is existed. Three dimensional elastoplastic finite element analyses were also carried out using the welded joint specimen models in order to calculate the Weibull stress. The critical loads for brittle fracture predicted by the Weibull stress criterion from CTOD test results of one-bead and multi-pass welded joint specimens show fairly good agreement with experimental results of welded joint specimens with geometrical discontinuity.

Evaluation of Residual Stress Effects on Brittle Fracture Strength Based on Weibull Stress Criterion

2008 ◽  
Vol 5 (6) ◽  
pp. 101524 ◽  
Author(s):  
Yoichi Yamashita ◽  
Fumiyoshi Minami ◽  
Richard Neu ◽  
Kim Wellin ◽  
Steven R. Thompson ◽  
...  
Keyword(s):  
Residual Stress ◽  
Brittle Fracture ◽  
Fracture Strength ◽  
Stress Criterion ◽  
Stress Effects ◽  
Strength Based ◽  
Weibull Stress

scholarly journals Study on Establish a Brittle Fracture Prediction Considering Different Crack Opening Modes Using Mixed-Mode Ratio

2021 ◽  
Vol 2 (4) ◽  
pp. 849-862
Author(s):  
Takuya Akahoshi ◽  
Koji Azuma ◽  
Tsutomu Iwashita ◽  
Toshiomi Itatani
Keyword(s):  
Finite Element ◽  
Brittle Fracture ◽  
Mixed Mode ◽  
Crack Opening ◽  
Steel Structures ◽  
Scale Model ◽  
Finite Element Models ◽  
Quantitative Index ◽  
Brittle Fractures ◽  
Weibull Stress

In this study, we propose a method for predicting the occurrence of brittle fractures in the beam-to-column joints of steel structures, considering different crack opening modes. We conducted experiments on beam-to-diaphragm joint specimens with varying plastically constrained cracks to reproduce brittle fractures. The experiments’ results demonstrated the effectiveness of the toughness scale model and the Weibull stress approach. In addition, we propose the mixed-mode ratio, which is a quantitative index of the mode difference, and we applied it to the finite element models of the specimens. In this study, we evaluate the validity of the mixed-mode ratio and explore the differences in crack opening modes, as they pertain to the occurrence of brittle fractures.

Sign in / Sign up

Export Citation Format

Share Document