Unified plastic limit solution for thick-walled cylinder with size effect
GAO Hong-wei1, HE Li-sha1, ZHANG Yong-qiang2
1. School of Aeronautics and Astronautics, Zhejiang University, Hangzhou 310027, China; 2. College of
Civil Engineering and Architecture, Zhejiang University, Hangzhou 310012, China
In order to expand the application of the classical plastic limit theory for thick-walled cylinder, a plastic limit analysis was conducted by using the unified yield criterion and a strain gradient plasticity theory for an internally pressurized thickwalled cylinder of elastic linear-hardening plastic material with the same tension-compression strength. A unified plastic limit solution with size effect was derived in a closed form, which was adapted to various materials with the same tension-compression strength, and the classical plasticity solution can be recovered as a special case of it. The size effect of strain-hardening level on the load-carrying capacity was analyzed based on the unified solution. Results showed that the size effect was significant as the characteristic length was in the level of micrometer. The relationship between the plastic limit loading and the material hardening level was analyzed. Results showed that the plastic limit loading increased with the increase of hardening level.
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