Advanced

On Low-Cycle Fatigue

Tryding, Johan LU (1990)
Abstract (Swedish)
Popular Abstract in English

The present work deals with fracture in structures which are exposed to relatively few cycles of static loading during their life-time (maximum some ten thousand). Structures exposed to nearly monotonic loading are rare, except for such loaded mainly by their own weight. In spite of this fact, fracture mechanic methods developed for monotone loading are commonly used on statically loaded structures, which may be exposed to several thousand major load cycles during their life-time. Examples are pressure vessels and oil tankers.

The methods used for monotone loading are, in their simplest form,

based on linear fracture mechanics. Generally, these methods can easily be used by... (More)
Popular Abstract in English

The present work deals with fracture in structures which are exposed to relatively few cycles of static loading during their life-time (maximum some ten thousand). Structures exposed to nearly monotonic loading are rare, except for such loaded mainly by their own weight. In spite of this fact, fracture mechanic methods developed for monotone loading are commonly used on statically loaded structures, which may be exposed to several thousand major load cycles during their life-time. Examples are pressure vessels and oil tankers.

The methods used for monotone loading are, in their simplest form,

based on linear fracture mechanics. Generally, these methods can easily be used by engineers, and the basic expressions needed are found in handbooks, e.g. in Tada et al. (1973). However, often the load is so high that non-linear fracture mechanics has to be considered. The procedure then becomes much more complicated, and, what is more serious, the theoretical grounds become weaker (Broberg, 1977).



The purpose of this work is to present a fracture mechanics method for

cyclic loading which is easy to use and, at the same time, predicts the number of load cycles a structure can withstand until it fails. It concentrates on non-linear crack growth, which is usually not covered by methods to predict failure under high-cycle fatigue conditions. A requirement at the onset of the work was, that the method should be based on expressions and data available in handbooks, and that it should not involve extensive calculations. (Less)
Abstract
The experimental results presented confirm the anticipation that it is extremely important not to confuse the concept of 'static loading' with the one of 'monotonic loading'. In principle three different crack configurations were investigated in: edge-cracks, internal flaws and surface cracks. The results showed that the same calculation method could be used for all the investigated crack types.

The main results deals with a method on how an engineer should design a structure in order to avoid final fracture and on how to get the material data needed by the test procedure.
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Thesis
publication status
published
subject
pages
7 pages
publisher
Lund University
language
English
LU publication?
yes
id
a991a237-7ca0-4dd4-bd06-5252a150a7f7 (old id 5153520)
date added to LUP
2015-04-20 14:45:38
date last changed
2016-09-19 08:45:10
@misc{a991a237-7ca0-4dd4-bd06-5252a150a7f7,
  abstract     = {The experimental results presented confirm the anticipation that it is extremely important not to confuse the concept of 'static loading' with the one of 'monotonic loading'. In principle three different crack configurations were investigated in: edge-cracks, internal flaws and surface cracks. The results showed that the same calculation method could be used for all the investigated crack types.<br/><br>
The main results deals with a method on how an engineer should design a structure in order to avoid final fracture and on how to get the material data needed by the test procedure.},
  author       = {Tryding, Johan},
  language     = {eng},
  pages        = {7},
  publisher    = {ARRAY(0x96fc878)},
  title        = {On Low-Cycle Fatigue},
  year         = {1990},
}