engleski

Experimental and numerical investigation of aluminium specimens with a circular hole subjected to tension

Stress concentration around a circular hole in a symmetric plate subjected to uniaxial tension is a well-known and extensively studied problem. Various experimental studies of this problem have been carried out in the last century, on specimens of different materials and with different shapes of holes [1], [2], but we will limit ourselves here to the fundamental example of a symmetric homogeneous and isotropic strip plate with a circular hole. The literature review [3], [4] shows that each successfully conducted experiment indicates that lower stress values occur at the edge of the hole than theoretically assumed. In other words, it has been observed that the stress profile along the specimen transverse section obtained theoretically does not match the experimental measurements. Motivated by the observed discrepancies, this paper is focused on answering two essential questions: can we confirm that the classical theory of elasticity does not describe the considered problem well enough, and can we propose a better theoretical prediction? For this purpose, we have performed the tensile tests on aluminium specimens. The experimentally measured strains have been compared with the results of a numerical model based on the classical theory of elasticity, and the discrepancies between the two sets of results reported in the literature have been confirmed. Hence, we have looked for a possible solution to this problem in the framework of an alternative continuum theory, the so-called micropolar (Cosserat) continuum theory [5], which is the subject of intense research of our group.

Koncentracija naprezanja, tenzometarsko mjerenje, eksperimentalno ispitivanje, metoda konačnih elemenata, mikropolarna teorija, inverzna analiza

nije evidentirano