含电流变体砂浆复合梁结构振动固有频率的理论研究

THEORETICAL STUDY ON NATURAL FREQUENCIES OF A CANTILEVER MORTAR BEAM WITH EMBEDDED ELECTRORHEOLOGICAL FLUID

以修正的RL线弹簧模型为基础,通过定义等效裂纹长度,建立了含电流变体的砂浆复合悬臂梁的振动模型,并得到理论计算复合梁频率的特征方程。根据实验数据确定模型的参数,并编制MATLAB程序来模拟含电流变体的砂浆悬臂梁随电场强度变化时自振频率的变化规律。研究结果表明,该模型的模拟值与实验值吻合得较好,尤其对一阶频率的模拟效果最好。本项研究为电流变体在实际工程结构振动控制领域的应用奠定了实验和理论基础。

Based on the revised line-spring(RL) model,a vibration model of a mortar cantilever beam with electrorheological fluid is reconstructed to calculate the eigenfrequencies by defining an equivalent crack length on the beam.Parameters of the model with various field-strengths and various frequencies are identified with test data and dicussed.Modeling is carried out with the MATLAB software to get the relation between the natural frequencies of the beam and the infensity of the electric field.The comparison between the experimental data and the predicted values by the simulation indicate that the proposed model is able to accurately describe the changing of frequencies due to different electric field-intensity,expecially for the first natural frequency.This study gives an experimental and theoretical basis for the application of ER fluid to vibration control in engineering structures.