Vibration-Based Damage Detection for a Prestressed Concrete Box Girder by Means of Subspace Analysis
Vibration-Based Damage Detection for a Prestressed Concrete Box Girder by Means of Subspace Analysis
复制标题
基于振动的子空间分析预应力混凝土箱梁损伤检测
DOI：
10.1061/ajrua6.0001185
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Takemura Kohei
中科院分区：
文献类型：
--
作者：
Zhao Lei;Kim Chul-Woo;Goi Yoshinao;Takemura Kohei
基于振动的土木结构损伤检测已得到积极的研究。基于加速度的损伤识别方法已经有很多种，其中基于子空间的系统识别理论已经比较成熟，并以其非迭代、计算量小等优点成为结构模态参数识别的主流方法。然而，传统的模态参数，包括模态频率，振型和阻尼比，并不总是敏感的实际土木结构的损伤。对某预应力混凝土箱梁进行了静载试验和锤击试验。在采用传统模态分析方法对结构进行分析的基础上，提出了基于零子空间分析的PC箱梁健康状态监测方法，并提出了反映损伤程度的指标。与传统的模态参数相比，该损伤指标具有更高的灵敏度和有效的精度来区分不同的结构损伤程度。此外，该方法还能明显地观察到预应力筋断裂引起的损伤，而损伤对模态频率的影响很小。
Vibration-based damage detection for civil structures has been actively investigated. Many acceleration-based damage detection methods have been developed, among which the subspace-based system identification theory has been well established and has been a popular way to identify the structure’s modal parameters, having the advantage of being non-iterative and computationally tractable. Nevertheless, traditional modal parameters, including modal frequencies, mode shapes, and damping ratios, are not always sensitive to damage in actual civil structures. In this paper, a series of static loading tests and nondestructive hammer tests were applied to a prestressed concrete (PC) box girder. After analyzing the structure by the traditional modal analysis method, a technique based on null subspace analysis is proposed to monitor the health state of the PC box girder, and an index reflecting the damage levels is proposed. Compared with traditional modal parameters, the proposed damage index shows higher sensitivity and efficient precision to distinguish different structural damage levels. What is more, the damage caused by fracturing of prestressing tendons, which only slightly affect changes in modal frequencies, can also be obviously observed by this method.