Nomogram of use for risk-targeting in the context of seismic design

Nomogram showing the sensitivity of the ratio lambda_ref/lambda_c to the values of X, beta and k1 within the context of risk-targeted seismic design. The isopleths show two example calculations using this graph by connecting with straight lines choices of lambda_ref/lambda_c and X and reading off the value of k1.

Where:

lambda_ref is the mean annual frequency of exceedance of S_a^ref

lambda_c is the mean annual frequency of collapse

X is the probability of collapse

beta is Standard deviation of S_a^c

k1 is the slope of the seismic hazard curve in log-log space

S_a^c is the pseudo-spectral acceleration at collapse

S_a^ref is the pseudo-spectral acceleration corresponding to ref

See Gkimprixis et al. (Comparison of methods to develop risk-targeted seismic design maps, doi: 10.1007/s10518-019-00629-w, 2019) for more details. This figure is Figure 11 of that open-access paper.

This nomogram was produced using Pynomo using Type 10 equations for three values of beta.