Search results for "Paris law"
showing 2 items of 2 documents
FATIGUE LIFE ANALYSIS OF RAIL-WELDS USING LINEAR ELASTIC FRACTURE MECHANICS
2019
The initiation and growth of fatigue cracking is mainly due to high stress concentration, heterogeneity and poor quality of weld. The detection and rectification of such weld defects are major concerns of rail network managers to reduce potential risk of rail breaks and derailments. To estimate the fatigue life of welded joints and to analyze the progress of fatigue cracks, a fracture mechanics-based analysis and fatigue models were developed using Finite Element Analysis. The initial flaw is obtained from a sample weld using ultrasonic flaw detecting machine test. Linear Elastic Fracture Mechanics (LEFM) approach based on the Paris law was applied to determine critical crack size and the n…
A methodology for the rapid characterization of Mode II delamination fatigue threshold in FRP composites
2019
Abstract A new methodology to measure the Mode II interlaminar fracture in fatigue for FRP composites is developed. The proposed methodology uses a Modified Transvers Crack Tensile (MTCT) specimen and is able to characterize the near threshold behavior in a robust, easier and significantly faster way than standard procedures. Analytical formulae, able to link the crack growth rate to the load or strain amplitudes, were found and verified, and their importance was explained, in particular, for what concerns the characterisation of the near threshold behavior. Experiments were performed both in load and strain control, while the delamination growth was monitored using different techniques inc…