Lower bound limit analysis of 2D steel frames with foundation-structure interaction

摘要

This work addresses limit analysis of 2D steel frames with foundation-structure interaction taking into account the foundation load capacity. A perfect plasticity model is used with convex and bounded plastic interaction surfaces. An interface element is used in order to obtain a lower bound-based problem description. Various criteria are considered: (N - V-z - M-y)-interactions for steel I-sections and (V - H - M)-interactions for shallow foundations on sands. The nonlinear criteria are linearized permitting use of linear programming software. A simple technique yields true lower bound formulations for 2-node standard frame elements taking into account the finite size of the frame joints. Parametric studies are conducted for two examples. (C) 2016 Elsevier Ltd. All rights reserved.