基于均布荷载面曲率的板类结构损伤定位研究

摘要

基于均布荷载面曲率方法对不同工况下的板类结构进行了损伤定位.该方法仅需要板结构损伤前和损伤后的前三阶模态频率和模态振型就可准确定位损伤位置.采用中心差分法构造了x和y方向的均布荷载面曲率,并成功地运用到板类结构的损伤定位中.数值模拟讨论了固定支承和三边固支时3种损伤情况下均布荷载面曲率方法的定位效果.研究发现:固定支承板中度面损伤时,均布荷载面曲率方法仅用第一阶模态数据就能有效定位损伤;而且均布荷载面曲率差值随着参与模态阶数的增加收敛得很快;轻度点损伤和多处损伤能够大致定位.%A method based on the uniform load surface curvature (ULSC) was employed to locate the damages of plate-like structures under different conditions.The method just requires the modal frequencies and the modal shapes of first few modes of damaged and undamaged plates.The central difference method was applied to obtain the ULSC and achieve the localization of damages in plate-like structures.With numerical simulation examples,the damage localizations in three different damage cases and two boundary conditions were discussed.It is found that the ULSC method can locate damage successfully in a four-side fixed support plate with a moderate surface damage.The uniform load surface converges rapidly with the increase of the number of participated modes.The ULSC can locate damages rougly in plates with a slight surface damage or multiple coexisting damages.