无条件稳定数值积分方法在拟动力实验中的应用研究

Application of an Unconditionally Stable Numeral Integration Algorithm in Pseudodynamic Testing

用无条件稳定的隐式α－方法代替目前的条件稳定的显式方法，通过数值迭代控制方法实现了拟动力实验．在此基础上进一步应用子结构技术，解决了刚度大、自由度较多结构采用传统的条件稳定数值积分方法进行拟动力实验的问题．应用不同数值积分方法进行的三层模型结构的实验结果表明，无条件稳定的数值积分方法的实验精度优于条件稳定的数值积分方法的精度．文中还就实验误差的控制补偿问题进行了讨论。

Through using unconditionally stable implicit αmethod instead of conditionally stable explicit algorithm, and introducing the substructure technique, the pseudodynamic tests for MDOF structures with high stiffness are succesfully performed. Testing results show that the unconditionally stable implicit αmethod is superior to the conditionally stable explicit algorithm in accuracy and numerical stability. An error compensation method based on the idea of instantaneous stiffness is proposed.