A crack growth analysis in critical structural components

english

2006

volume 40, issue 4

Inštitut za kovinske materiale in tehnologije
(Obvezni izvod spletne publikacije)

The supervising and health monitoring of structures is a new field that has been of increasing importance with regard to control durability, stability and safety as well as for estimating the life span of the structure. Crack growth is interesting for the proper evaluation of the reliability of structural parts. Different methods are used to record the actual situation in order to get reliable information about the on-site structure and structural elements. The experimental techniques in fracture mechanics are employed for determining the stress-intensity factors (SIFs) of the cracks in deformed structures. A procedure for the simulation of crack propagation for multiple cracks was introduced and SIFs have been calculated by using the finite-element method. The crack growth of a single crack or a periodic array of cracks initiated at the stiffeners in a stiffened panel has been investigated. The optical method of caustics is established for the application to mechanically isotropic materials through the process of SIF's evaluation and has advantageously improved applications with fiber-reinforced composites. Using high-speed photography and optical interferometric methods, we analyzed the phenomena of the dynamic failure process in composites and high-speed delamination. Valuable information gathered by the analysis of critical structural components should be important for making decisions about the structural repairing or the halting of a plant's production. Significant examples are the analysis of structures of the deck of a ship, the jacket of a gas and oil platform and the aeolian vibrations in electrical transmission lines that can cause severe damage or even the breakdown of the conductor due to material fatigue.

16.09.2009