摘要
针对混凝土结构中常见的裂缝损伤,分析了裂缝对应力波的作用机理,提出用于检测裂缝的基于智能钢筋PZT网络的主动监测系统。将PZT薄片按照特定的规律安装在钢筋表面形成智能钢筋,通过不同智能钢筋上异位布置的PZT构成了覆盖整个结构的监测网络。实验室浇筑钢筋混凝土梁试件,并通过设置不同深度和不同数量的人工裂缝来模拟梁在受力状态下的裂缝开展过程,记录不同损伤状态下智能钢筋的输出信号。实验结果表明,智能钢筋的输出信号会随着单裂缝深度的增加而线性减小,且随着裂缝数目的增加呈指数形式衰减。其定量关系为损伤识别系统的建立奠定了一定的基础。
In order to detect the most common phenomenon in crack damage of concrete structure,the influence of cracks on the propagation of stress wave was analyzed,furthermore an active sensing diagnostic system based on PZT network for crack detection was proposed. PZT elements were mounted on the surface of reinforcement bar to form a smart rebar,and these rebars were arranged in an optimized way to form a diagnostic network. Concrete beams with fullsize were cast in experimental tests,and artificial cracks with different depth and different numbers were made to mimic the development of cracks. Test results showed that the amplitude of sensor output signals is deceased linearly with a crack depth,and is decreased exponentially with the increased crack numbers. The quantitative relationship made a solid foundation for the build-up of the damage identification system.
出处
《实验室研究与探索》
CAS
北大核心
2016年第6期4-8,共5页
Research and Exploration In Laboratory
基金
国家自然科学基金项目(51278300
61227071)
深圳科创委基金项目(CXZZ20140508140740862)
关键词
压电陶瓷
智能钢筋
应力波
混凝土结构
裂缝损伤
主动监测
piezoelectric ceramics
smart rebar
stress waves
concrete structure
crack damage
active sensing diagnostic system
