Development and Verification of Damage Prediction Method by Mode Shapes for Structures

• Main Authors: Huai-Chih Chang, 張懷智
• Other Authors: Bor-Tsuen Wang
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/84756825554266084137

碩士 === 國立屏東科技大學 === 機械工程系 === 94 === This work adopts strain energy method as the damage detection index and combines the Lagrange-Interpolation method (LIM) as well as differential quadrature method (DQM) to develop the damage detection algorithm for1-D beam, Bolt-Jointed structures and 2-D plate structures. By performing either finite element analysis (FEA) theoretical or experimental modal analysis (EMA) on the structure, one can obtain the damaged and non-damaged structural mode shapes, that are the input to the prediction program, and, therefore, the damage location can be detected. This work uses FEA and EMA to construct both the damaged and non-damaged models and determine their mode shapes. The LIM is introduced to expand the measurement points and the DQM is applied to determine the derivatives of mode shapes, and so forth the damage index over the structure can also be expanded and beneficial to identify the damage location and evaluation of 1-D and 2-D structures. Results show that the effectiveness of damage detection can be improved, especially for those experimental data limited. The employment of LIM can increase the accuracy of damage detection. The methodology can be applied to general 2-D structures.