Benefit-Cost Ratio#

Retrofitting benefit/cost ratio maps#

Ratio maps from the Retrofitting Benefit/Cost Ratio calculator require loss exceedance curves, which can be calculated using the Classical Probabilistic Risk calculator. For this reason, the parameters sourceModelTreePath and gsimTreePath are also included in this NRML schema, so the whole calculation process can be traced back. The results for each asset are stored as depicted in the table below.

Example benefit-cost ratio map output:

lon

lat

asset_ref

aal_original

aal_retrofitted

bcr

80.0888

28.8612

a1846

966,606

53,037

1.72

80.0888

28.8612

a4119

225,788

26,639

1.46

80.0888

28.8612

a6444

444,595

16,953

1.33

80.0888

28.8612

a8717

106,907

10,086

0.39

80.0888

28.9362

a1784

964,381

53,008

1.92

80.0888

28.9362

a4057

225,192

26,597

1.64

80.0888

28.9362

a6382

443,388

16,953

1.49

80.0888

28.9362

a8655

106,673

10,081

0.44

80.1292

29.0375

a2250

1,109,310

60,989

2.08

80.1292

29.0375

a4523

2,785,790

329,083

1.78

  • interestRate: this parameter represents the interest rate used in the time-value of money calculations

  • assetLifeExpectancy: this parameter specifies the life expectancy (or design life) of the assets considered for the calculations

  • node: this schema follows the same node structure already presented for the loss maps, however, instead of losses for each asset, the benefit/cost ratio (ratio), the average annual loss considering the original vulnerability (aalOrig) and the average annual loss for the retrofitted (aalRetr) configuration of the assets are provided.