Derived Design Spectra
From observation of the above spectra, it can be seen that the maximum acceleration, velocity, and displacement occur in different period ranges. In addition, the maximum value is usually contained in a region where the spectral values are nearly constant. The spectrum can then be roughly divided into three regions: a region where acceleration is nearly constant, one where velocity is nearly constant, and one where displacement is nearly constant.
M. Newmark and W. J. Hall developed a particularly simple and useful procedure
for applying these basic principles to the development of elastic design
spectra, which is explained in detail in the next page.