【摘要】 为了有效利用压电陶瓷传感器进行混凝土结构局部损伤、缺陷的精细识别,并为相关试验提供理论指导,对基于压电陶瓷片(PZT)波传播法进行混凝土结构损伤识别的方法进行了数值模拟。首先分析了PZT波传播法的基本原理,并提出了基于大型有限元分析软件ANSYS的多物理场耦合分析的PZT波传播法的数值模拟方法。然后,针对表面粘贴PZT激励器/传感器并预设裂缝、孔洞损伤的混凝土梁式构件,建立了3D精细化有限元模型,分析了PZT激励器在不同激励电压幅值与频率下激发的应力波幅值衰减程度、传播时间等与混凝土梁损伤类型与程度之间的关系。结果表明:激励电压只影响波传播的幅值,且与之成正比关系;波传播能量的损耗程度与结构损伤程度成正比;激励频率对波的传播时间和能量损耗有较大的影响。根据研究数值模拟结果可建立波传播的特征值与结构损伤形式之间的初步关系,为下一步试验研究工作提供了理论指导,同时也证实了利用大型有限元分析软件对基于PZT的波传播法进行混凝土结构损伤识别的数值模拟是可行的。更多还原

【Abstract】 In order to identify the local damage of concrete structure effectively using PZT sensors and provide the theoretical guidance for the related tests,the numerical simulation of damage detection on concrete structure based on wave propagation method with PZT sensors is carried out in present study.Firstly,the basic principle of wave propagation method is analysized and the method of numerical simulation based on wave propagation method using multi-physics coupling parts of finite element analysis software is proposed.Secondly,the 3D finite element models for a concrete beam attaching PZT actuator/sensor with pre-cracks,pre-holes injury are established,and the relation between propagation time and attenuation of amplitude caused by different amplitude and frequency of excitation voltage and the type and extent of injury of concrete beam are studied.The results show that excitation voltage is directly proportional to the amplitude of wave propagation.Besides,depletion of wave is proportional to the degree and extent of structural damage.In addition,excitation frequency has great impact on the wave propagation time and energy depletion of wave.The efficiency of the proposed method is evaluated and validated.更多还原