Healthmonitoring of building constructions with crack-like defects
Pages 77-83
This article deals with structural inspection of the flaws caused by such factors as overloading, differential settlements of construction’s foundation, etc. In order to detect them and define their type and size, modern non destructive equipment such as ultrasonic tomography mira1040 and ultrasonic flaw detector A 1212 MASTER are used. Since cracks increase the stress, they are one of most dangerous defects, so some calculation for analyzing stresses distributions near the crack tip and the whole construction stress redistribution caused by cracking are required. Such calculations are rather complicated, that's why the most suitable methods are computational methods.Practical application of FEM is known as finite element analysis (FEA). FEA is applied in engineering as a computational tool for performing engineering analysis. In this research Finite Element Method is used for defining danger level caused by cracking in a construction, whether it is a through crack or a surface crack. Two types of meshing near the crack tip were considered. The first is refined mesh near the crack tip, it is done using finite elements of smaller size therefore increasing the number of elements and calculation time. The second mesh is done by skewing mid side nodes of the first row of elements to the 1/4 point for crack tip, so the elements number does not increase, the same as calculation time, while accuracy of calculating stresses near the crack tip matches the accuracy in case of refined mesh.As a research result this article describes the methods of detecting and analyzing the structures that have been flawed during the building operation.
DOI: 10.22227/1997-0935.2013.12.77-83
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