Vulnerability module

Vulnerability module

For the derivation of vulnerability functions, two methodologies have been implemented in the VMTK. In the first approach, the probability distribution of loss ratio is computed using the resulting fragility model and a damage-to-loss model (i.e., relation between each damage state and the corresponding loss ratio). The damage-to-loss model is provided as a comma delimited file containing the values arranged in a column array. The second methodology included in the toolkit the loss ratios (LR|IM) are computed directly from the results of the nonlinear dynamic analyses using a relationship between the engineering demand parameter and the expected loss ratio (hereafter referred as EDP-to-loss model). The EDP-to-loss model is defined in a two-column array comma delimited file where the first column contains the EDP thresholds and the second the expected loss ratio. The toolkit also allows to export the expected uncertainty around the losses. If this option is selected the toolkit will create a file with the expected sigma for each loss value in the vulnerability curve.

Outputs

The toolkit exports a csv file with the IML and expected loss ratio alongside an estimate of the uncertainty if the option has been selected.

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