钢筋混凝土梁振动特性参数与损伤状况关系的数值仿真研究

基于分离式有限元理论,分别建立了存在钢筋混凝土局部松脱等多种形式损伤的钢筋混凝土梁横向弯曲振动力学模型,利用此模型能够计算各种损伤梁的固有频率等振动特性参数。对这些振动特性参数与各种损伤的状况之间的关系进行了数值仿真研究。提出固有频率可以作为钢筋混凝土梁损伤定性辨识的指标;针对不同的损伤形式,位移模态振型、曲率模态振型和剩余模态力向量是对局部损伤位置敏感的振动特性参数,可以利用敏感参数的绝对残差向量进行局部损伤的定位辨识;敏感参数绝对残差向量的范数与损伤程度具有良好的单调性关系,可以作为局部损伤定量辨识的指标。

Numerical Simulation to Relation Between Vibration Characteristic and Damage Condition of Reinforced Concrete Beam

Based on separate finite element theory,the mechanical model was established for a reinforced Concrete beam(RCB) with local looseness and under bending vibration to evaluate the vibration parameters of damaged RCB,eg.,the natural frequency.The numerical simulation to the relationship between vibration characteristic parameter and damage condition was carried out.The natural frequency serves as an important index to determine to be damaged or not.For varions damage types,the displacement mode curvature mode and residual mode force vector were sensitive to damage ocation of the damage in a RCB,the absolute remaining difference vector(ARDV) enables to used to detect the local damages in a RCB.