frbca

The goal of frbca is to conduct benefit-cost analysis (BCA) for buildings archetypes designed for functional recovery. The inputs include:

• Expected Annualized Losses (EALs) for (i) a baseline (code-conforming) design and (ii) recovery-based design interventions
• Structural and nonstructural costs for both (i) and (ii)
• A list of analysis parameters, including discount rate, time horizon, and economic analysis parameters such as business income

Installation

You can install the development version of frbca like so:

You can install frbca from GitHub with:

devtools::install_github("juanfung/frbca")

Expected inputs

To run the analysis, provide two inputs in tabular (eg, data.frame) form:

Expected annualized losses (EALs) from a performance assessment

Each row is an archetype model. Expected (minimum) columns:

| variable                 | type  | description                        |
|--------------------------|-------|------------------------------------|
| model                    | <chr> | unique model name or id            |
| intervention             | {0,1} | baseline design = 0; otherwise = 1 |
| num_stories              | <dbl> | number of stories                  |
| loss_ratio               | <dbl> | loss ratio                         |
| repair_costs             | <dbl> | repair costs, in dollars           |
| re_occupancy_time        | <dbl> | re-occupancy time, in days         |
| functional_recovery_time | <dbl> | functional recovery time, in days  |

Construction costs

Each row is an archetype model. Expected (minimum) columns:

| variable     | type  | description                                  |
|--------------|-------|----------------------------------------------|
| model        | <chr> | unique model name or id                      |
| intervention | {0,1} | baseline design = 0; otherwise = 1           |
| num_stories  | <dbl> | number of stories                            |
| c_s          | <dbl> | structural construction costs, in dollars    |
| c_ns         | <dbl> | nonstructural construction costs, in dollars |

In addition, several parameters are required in list form. The following are the base parameters required under sub-list input_param$parameters$base:

| parameter    | type    | description                                        |
|--------------|---------|----------------------------------------------------|
| floor_area   | <dbl>   | total square footage per story                     |
| delta        | <delta> | discount rate                                      |
| T            | <dbl>   | planning horizon, in years                         |
| bi           | <dbl>   | business income                                    |
| ri           | <dbl>   | rental income                                      |
| displacement | <dbl>   | occupant-incurred costs of displacement            |
| tenant       | <dbl>   | number of tenants per square foot                  |
| recapture    | <dbl>   | recapture rate for rental income                   |
| sc           | <sc>    | supply-chain multiplier for business income losses |

In addition, parameter values for sensitivity analysis should be provided under the sub-list input_param$parameters$sensitivity. For example, sensitivity analysis for delta would be conducted based on provided values input_param$parameters$sensitivity$delta$low and input_param$parameters$sensitivity$delta$high.

Example

This is a basic example which shows you how to solve a common problem:

## NOT RUN
library(frbca)

## assuming input data is loaded and parameters are set...

## run analysis
output <- frbca::frbca(input_eal, input_cost, input_param)

## generate results plot with sensitivity analysis
frbca::plot_frbca(output, n_floors=4, system='RCMF')