Fracture Mechanics and Nondestructive Testing of Brittle Materials

1972 ◽  
Vol 94 (1) ◽  
pp. 291-297 ◽  
Author(s):  
W. G. Clark
Keyword(s):  
Fracture Mechanics ◽  
Nondestructive Testing ◽  
Fracture Behavior ◽  
Brittle Materials ◽  
Orientation Distribution ◽  
Nondestructive Inspection ◽  
Structural Failure ◽  
Practical Engineering ◽  
Basic Concepts ◽  
Defect Morphology

The fracture mechanics approach to the development of meaningful nondestructive inspection requirements is presented. The basic concepts underlying the technology are reviewed and the practical engineering aspects of this approach to the prevention of structural failure are demonstrated. Particular emphasis is placed on evaluating the influence of defect morphology (size, shape, orientation, distribution, etc.) on fracture behavior. A hypothetical inspection problem is included and the pertinent considerations associated with the development of a realistic nondestructive inspection specification are discussed in detail.

Fracture Toughness Testing and its Implications to Engineering Fracture Mechanics Analysis of Energy Pipelines

2018 ◽  
Author(s):  
Sergio Limon ◽  
Peter Martin ◽  
Mike Barnum ◽  
Robert Pilarczyk
Keyword(s):  
Fracture Toughness ◽  
Fracture Mechanics ◽  
Test Data ◽  
Fracture Mode ◽  
Fracture Process ◽  
Fracture Behavior ◽  
Fracture Initiation ◽  
Fracture Toughness Testing ◽  
Final Fracture ◽  
Toughness Testing

The fracture process of energy pipelines can be described in terms of fracture initiation, stable fracture propagation and final fracture or fracture arrest. Each of these stages, and the final fracture mode (leak or rupture), are directly impacted by the tendency towards brittle or ductile behavior that line pipe steels have the capacity to exhibit. Vintage and modern low carbon steels, such as those used to manufacture energy pipelines, exhibit a temperature-dependent transition from ductile-to-brittle behavior that affects the fracture behavior. There are numerous definitions of fracture toughness in common usage, depending on the stage of the fracture process and the behavior or fracture mode being evaluated. The most commonly used definitions in engineering fracture analysis of pipelines with cracks or long-seam weld defects are related to fracture initiation, stable propagation or final fracture. When choosing fracture toughness test data for use in engineering Fracture Mechanics-based assessments of energy pipelines, it is important to identify the stage of the fracture process and the expected fracture behavior in order to appropriately select test data that represent equivalent conditions. A mismatch between the physical fracture event being modeled and the chosen experimental fracture toughness data can result in unreliable predictions or overly conservative results. This paper presents a description of the physical fracture process, behavior and failure modes that pipelines commonly exhibit as they relate to fracture toughness testing, and their implications when evaluating cracks and cracks-like features in pipelines. Because pipeline operators, and practitioners of engineering Fracture Mechanics analyses, are often faced with the challenge of only having Charpy fracture toughness available, this paper also presents a review of the various correlations of Charpy toughness data to fracture toughness data expressed in terms of KIC or JIC. Considerations with the selection of an appropriate correlation for determining the failure pressure of pipelines in the presence of cracks and long-seam weld anomalies will be discussed.

Experimental Study on the Failure Criterion for Brittle Materials in Compression

2011 ◽  
Vol 320 ◽  
pp. 259-262
Author(s):  
Xu Ran ◽  
Zhe Ming Zhu ◽  
Hao Tang
Keyword(s):  
Thin Film ◽  
Experimental Study ◽  
Compressive Strength ◽  
Fracture Mechanics ◽  
Failure Criterion ◽  
Brittle Materials ◽  
Experimental Results ◽  
Experiment Study ◽  
Confining Stress ◽  
Theoretical Results

The mechanical behavior of multi-cracks under compression has become a very important project in the field of fracture mechanics and rock mechanics. In this paper, based on the previous theoretical results of the failure criterion for brittle materials under compression, experiment study is implemented. The specimens are square plates and are made of cement, sand and water, and the cracks are made by using a very thin film (0.1 mm). The relations of material compressive strength versus crack spacing and the lateral confining stress are obtained from experimental results. The experimental results agree well with the failure criterion for brittle materials under compression, which indicates that the criterion is effective and applicable.

scholarly journals Fracture Mechanics Analysis on Structural Failure of Ship

1984 ◽  
Vol 1984 (156) ◽  
pp. 542-549
Author(s):  
Yoshiro Masuda ◽  
Hitoshi Ikeda ◽  
Yasuharu Tsutsui ◽  
Yukio Ino ◽  
Kenji Yasuda
Keyword(s):  
Fracture Mechanics ◽  
Structural Failure ◽  
Mechanics Analysis
Sign in / Sign up

Export Citation Format

Share Document