Bi-normalized Newmark–Hall spectra for seismic design and assessment

A bi-normalized Newmark–Hall response spectrum is presented for seismic design and assessment of structures. The period axis is normalized with respect to a characteristic period relating only to peak ground-motion parameters. The amplification factors are determined through a statistical analysis by normalizing spectral pseudo-acceleration, spectral pseudo-velocity, and spectral displacement, relative to peak ground acceleration, peak ground velocity, and peak ground displacement, respectively, in the low-, intermediate-, and high-period ranges, which do not need to be prescribed prior to normalization. A total of 671 three-component accelerograms are selected from the New Zealand Strong Motion Database for the statistical analysis. The relationship between peak ground-motion parameters is studied, enabling the construction of a design spectrum from either a given design scenario earthquake, or a code-specified peak ground acceleration value.