Structural damage assessment under varying temperature conditions
Structural damage assessment under varying temperature conditions
复制标题
DOI：
10.1177/1475921711419995
复制
发表时间：
2012-05
期刊：
影响因子：
--
通讯作者：
Viviana Meruane;W. Heylen
中科院分区：
文献类型：
--
作者：
Viviana Meruane;W. Heylen
固有频率和振型等模态参数是结构损伤的敏感指标。然而，它们不仅对损坏很敏感，而且对环境条件也很敏感，比如湿度、风，最重要的是温度。对于土木工程结构而言，环境条件产生的模态变化可能等于或大于损伤产生的模态变化。提出了一种能够处理温度变化的损伤检测方法。目标函数关联模态振型和固有频率，并行遗传算法处理反问题。该结构的数值模型假定材料的弹性模量与温度有关。该算法同时更新温度和损伤参数。因此，有可能区分温度影响和实际损坏事件。三跨桥梁的仿真数据和I-40大桥的实验数据验证了所提出的方法。结果表明，该算法能够在温度变化的情况下对实验损伤进行评估。
Modal parameters such as natural frequencies and mode shapes are sensitive indicators of structural damage. However, they are not only sensitive to damage, but also to the environmental conditions such as, humidity, wind and most important, temperature. For civil engineering structures, modal changes produced by environmental conditions can be equivalent or greater than the ones produced by damage. This article proposes a damage detection method which is able to deal with temperature variations. The objective function correlates mode shapes and natural frequencies, and a parallel genetic algorithm handles the inverse problem. The numerical model of the structure assumes that the elasticity modulus of the materials is temperature-dependent. The algorithm updates the temperature and damage parameters together. Therefore, it is possible to distinguish between temperature effects and real damage events. Simulated data of a three-span bridge and experimental one of the I-40 Bridge validate the proposed methodology. Results show that the proposed algorithm is able to assess the experimental damage despite of temperature variations.