R code for random vibration theory analysis, and a D5-75% oscillator duration model, as detailed in C. Van Houtte, T. Larkin and C. Holden (2018), On durations peak factors and nonstationarity corrections in seismic hazard applications of random vibration theory, Bulletin of the Seismological Society of America, doi: 10.1785/0120170076

Detail of inputs, outputs and required packages can be found in the R script.