CAJ | 학술논문

在传统的基于模型修正的损伤识别中，由于实测模态信息有限而待识别参数过多，往往导致损伤识别方程出现较大误差，从而限制了该方法在复杂结构中的应用。为解决这一问题，对结构的自由度进行了分解，将损伤结构中模态振型的未测量部分表达为已测量到的模态振型、模态频率以及结构其它参数的函数。将损伤视为结构单元刚度的减小，利用完好结构的计算模态数据以及损伤结构扩充后的实测模态数据，建立了结构的损伤识别方程。运用信赖域优化算法对具有双重约束条件的目标函数进行最小化，识别出了结构各单元的刚度损伤参数。通过两个损伤识别数值仿真算例及实验验证，结果表明，在测点数量有限及测试噪声等不利因素影响下，所提方法只需运用少量的实测模态信息，即可实现结构损伤位置及程度的准确识别，同时算法具有较好的鲁棒性。
재전통적기우모형수정적손상식별중，유우실측모태신식유한이대식별삼수과다，왕왕도치손상식별방정출현교대오차，종이한제료해방법재복잡결구중적응용。위해결저일문제，대결구적자유도진행료분해，장손상결구중모태진형적미측량부분표체위이측량도적모태진형、모태빈솔이급결구기타삼수적함수。장손상시위결구단원강도적감소，이용완호결구적계산모태수거이급손상결구확충후적실측모태수거，건립료결구적손상식별방정。운용신뢰역우화산법대구유쌍중약속조건적목표함수진행최소화，식별출료결구각단원적강도손상삼수。통과량개손상식별수치방진산례급실험험증，결과표명，재측점수량유한급측시조성등불리인소영향하，소제방법지수운용소량적실측모태신식，즉가실현결구손상위치급정도적준학식별，동시산법구유교호적로봉성。
Owing to that the measured modal data is far less than parameters to be identified and the damage identification equations always have larger errors,these lead to the application of the traditional damage detection based on model updating is always limited in complex structures.Here,the drawback was solved by dividing structural DOFs into measured and unmeasured parts.Meanwhile,the unmeasured parts of the modal shapes of the damaged structure were characterized as a function of the structural parameters and the modal shapes of measured parts.Considering damage as a reduction of element stiffness,then the calculated modal data of an intact structure and the measured modal data of the corresponding damaged structure were used to establish the damage detect equation.The dual constrained objective function was minimized to recognize the changes of structural parameters by utilizing the trust region optimization method. The proposed method were verified with two numerical simulation examples and a damage detection test.The results showed that the proposed method has a good ability to detect any damage of structures using incomplete measured modal data,and the algorithm also has a good robustness.