简支梁损伤识别的特征方程曲线交点法

基于扭转弹簧模型的裂纹梁振动分析，推导了含单边边缘裂纹简支梁振动频率特征方程，提出了“特征方程曲线交点法”结合“附加质量”的方法．通过绘制相应于损伤梁前几阶固有频率的裂纹深度一位置的关系曲线，并求解其交点识别裂纹参数，解决了由于简支梁的对称性导致的损伤位置的误判问题．数值模拟结果显示，本文方法具有很好的识别精度．

Damage identification of simple supported beam based on the curve intersection of characterisitic equation

Based on the rotational spring model, the characteristic equation of the cracked simple surpported beam is derived, the ＂point of intersection curves of the characteristic equation method＂ is proposed and combined with the ＂added mass＂ method, the method involves obtaining plots of its depth with the crack location for the first three natural frequencies through the characteristic equation. The point of intersection of three curves gives the crack parameters, the misjudgement problem of the damage location due to the symmetry is solved. The results of the simulation demonstrated the accuracy of the method.