Papers by Author: Li Song

Abstract: The characteristics of interface affect the behaviors of a whole structure considerably. The interface along with its neighbouring region is defined as the interface region and the equivalent parameters in the interface region used in the analysis are obtained by both theoretical and experimental methods. A structure including interface was taken as an example, whose calculated model was made by the interface stress element method. The comparison between the results of calculation and experiment is presented to illustrate the feasibility and effectiveness of the proposed approach.

Abstract: The flaws such as crack or slag inclusion, in the welded seam of header of a 300MW steam turbine generator unit, were detected by the ultrasonic non-destructive inspection. Based on the crack modeling, the finite element method (FEM) was used to calculate and analyze the displacement field, stress field and stress intensity factors of the cracks under the conditions of warm start, cold start and normal operation, and the residual service life was predicted. Analyzing results showed that these flaws would not bring about primary brittle fracture and propagation of crack was harmless to safe in operation.