Engineering Transactions, 26, 1, pp. 131-178, 1978

Metoda Kaustyk - Nowa Metoda Doświadczalna Badania Osobliwości Pola Naprężenia

P.S. Theocaris
Politechnika Państwowa, Ateny
Greece

W pracy opisane są podstawy nowej metody, zwanej metoda kaustyk służącej do analizy osobliwych pól napreżeń. Podane są też przykłady zastosowań. W metodzie tej promień światła pada na powierzchnie próbki w otoczeniu osobliwości pola napreżeń. Przepuszczone lub odbite promienie świetlne, wskutek gwałtownych zmian grubości płytki oraz zmian współczynnika załamania, ulegają rozproszeniu. Po zrzutowaniu na odpowiedni ekran skupiają się one wzdłuż pewnej krzywej osobliwej. Krzywa ta, zwana kaustyka zawiera istotne informacje o osobliwości pola napreżeń. W ten sposób osobliwość pola napreżeń zostaje przekształcona w osobliwość optyczną, która może być zbadana na ekranie. Pomiar geometrycznych parametrów kaustyki pozwala wyznaczyć parametry osobliwego pola napreżeń. Podano szereg zastosowań metody do rozwiazywania zagadnień tyczących: 1) pęknięć, 2) obciążeń skupionych i rozłożonych, 3) osobliwości w wierzchołkach kompozytów (wielokątów). Otrzymane w powyższy sposób wyniki doświadczalne dobrze zgadzają się z analiza teoretyczna.

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