基于稳态响应规律的双线性滞回模型等效参数研究

Study on Equivalent Parameters of Bilinear Hysteretic Model Based on Steady-state Response Law

为了研究等效线性化方法的位移估算精度,以双线性滞回模型为分析模型,分析了非线性单自由度体系的自由振动过程,指出采用割线刚度法(R-H法)计算的等效参数与实际结果偏差较大,进而提出了一种简谐力作用下的等效参数计算方法。考虑了简谐激励的激励周期以及结构振动的位移峰值对计算结果的影响,通过数值分析对不同参数对应下的非线性体系进行等效线性化分析,验证了所提出的等效参数计算方法的有效性与准确性。结果表明,采用R-H法计算的等效刚度偏大,而改进方法能够合理估算非线性时程位移结果,其计算精度优于R-H法。

In order to study the displacement estimation accuracy of equivalent linearization methods,a bilinear hysteresis model was used as the analysis model to analyze the free vibration process of a nonlinear single degree of freedom system.It was pointed out that the equivalent parameters calculated by the secant rigidity method(R-H method)had a significant deviation from the actual results.A method for calculating equivalent parameters was proposed under the action of harmonic forces.The influence of the excitation period of harmonic excitation and the displacement peak of structural vibration on the calculation results were taken into account.The equivalent linearization analysis was conducted on the nonlinear system corresponding to different parameters through numerical analysis to verify the effectiveness and accuracy of the proposed equivalent parameter calculation method.The results show that the equivalent stiffness calculated by the R-H method is relatively higher.While the improved method can reasonably estimate the nonlinear time history displacement results,and the calculation accuracy is better than the R-H method.