The properties of frequency response of five kinds of model materials in hydrotechnics are discussed and analyzed by the static tension test and the dynamic cantilever beam test. The frequency response and the changing of the modal dynamic modulus of elasticity are compared between linear elastic and viscoelastic materials. The results show that the modal dynamic modulus of elasticity for linear elastic material is insensitive to frequency and remains stable, while the modal modulus for viscoelastic material changes obviously with frequency, especially at low frequency, which leads to large simulation errors. In this paper, the line portion of the frequency response curve is suggested to be the working frequency, which can eliminate large simulation errors and result in ideal results.