국부하중을 받는 원통쉘의 극한해석에 관한 연구

Abstract

본 연구에서는 국부하중을 받는 강완전소성체로 된 원통쉘의 극한해서에 관하여 연구하였다.

축대칭 링하중과 균일한 대압력이 작용할 때, 근사화시킨 항복곡면을 사용하여 소성변형에 관한 폐형해를 구하였다. 그 해를 분석한 결과 무차원 출방향응력(??) 이 0.3보다 크고, 무차원 대압력폭(??)이 1보다 작을 때 축방향응력의 영향이 상당히 큼을 발견하였다. 무차원 축방향응력이 0.2보다 작을 때에는 이것의 영향을 무시할 수 있으며, 무차원 대압력폭이 2보다 클 경우에도 축방향응력의 영향은 매우 작아 무시할 수 있음을 알게 되었다.

소성붕괴현상을 고찰하기 위하여 극한 붕괴실험을 실시하였으며, 이 실허의 결과는 정적소성붕괴이론과 비교적 잘 일치하였다.

The effect of axial stress on the plastic deformation of rigid-perfectly plastic cylindrical shell under the localized load is investigated. It is assumed that the shell is constructed with the material of Tresca's yeld criterion. A closed form solutions are obtained for uniform band pressure by using the circumscribed tield surface.

The analysis show that the effect of axial stress is of considerable importance when the dimensionless axial stress (??) is greater than 0.3 and dimensionless width of band pressure (??) is less than 1. It also appears that the effect of axial stress is nelegible when the axial stress is less than 0.2 or the width of band pressure is greater than 2.

In order to observe the phenomena of plastic collapses, a static collapse experiment was conducted. According to the result of this experiment, the theory is in good agreement with the experimental result.

The effect of axial stress on the plastic deformation of rigid-perfectly plastic cylindrical shell under the localized load is investigated. It is assumed that the shell is constructed with the material of Tresca's yeld criterion. A closed form solutions are obtained for uniform band pressure by using the circumscribed tield surface.

The analysis show that the effect of axial stress is of considerable importance when the dimensionless axial stress (??) is greater than 0.3 and dimensionless width of band pressure (??) is less than 1. It also appears that the effect of axial stress is nelegible when the axial stress is less than 0.2 or the width of band pressure is greater than 2.

In order to observe the phenomena of plastic collapses, a static collapse experiment was conducted. According to the result of this experiment, the theory is in good agreement with the experimental result.