AN ACCURATE MODAL SUPERPOSITION METHOD FOR COMPUTING MODE SHAPE DERIVATIVES IN STRUCTURAL DYNAMICS

The modal superposition method is often used to obtain mode shape derivatives. However, it can not give an accurate solution and the errors may become significant, when more high-frequency modes are truncated. This paper deals with the contribution due to the unavailable high-frequency modes to mode shape derivatives, proves that it can be expressed by the available low-frequency modes and the system matrixes, and presents a numerical algorithm. Numerical examples show that the method is correct and can imp...