Questions for R2D program

[sejin09]

Hello,

I'm trying to find out if it is possible to simulate wind-borne debris and their impacts in R2D program for strong wind or hurricane events. Because wind-borne debris can break windows or external building materials, modeling properties or internal wind pressure distribution can be changed during simulations. So here are my questions: 1) Do you think it's possible to change the modeling properties or aerodynamic characteristics of buildings during the simulation? 2) Can I add debris trajectory module to the R2D program?

Thanks

[adamzs]

Hi Sejin,

The currently available modules consider wind-borne debris using the approach from HAZUS: the debris environment is characterized for every building (one of four possibilities), and the (building level) damage state at any given wind speed is influenced by the selected environment. This is a crude but efficient approach that does not take advantage of any local simulation.

You can certainly:
- Introduce more sophisticated archetypes that better represent the aerodynamic characteristics of various buildings and debris environments.
- Introduce a more sophisticated mapping of available information on the built environment to debris environment classes
- Add a debris trajectory module to R2D.

The first two options are relatively straightforward. The complexity of the last one depends on the methodology you plan to use to model the creation (i.e. after buildings or the environment are damaged) and path of debris in the area. If you can tell us a bit more about that methodology, I can give you more information about the complexity of implementing it in our backend and in R2D.

Adam

[sejin09]

Thanks Adam. I have one more question.

For each time step, I will try to calculate the external and internal pressure to get the net pressure. Once the net wind pressure exceeds the resistance of a building component (e.g., roof sheathing), this component will become windborne and internal pressurization of the building will occur. In this situation, the internal pressure model should be updated and any newly released debris objects are traced. This iterative process continues until equilibrium is achieved. So my question is, do you think this kind of iterative process is realizable in R2D program? Or is this too complex? If it's not too complicate, could you give me an idea which R2D component I should modify?

Thanks

[adamzs]

Hi Sejin,

Can you provide some information on the tools you typically use for these calculations?

How do you evaluate the external and internal pressure on the building? For example, is it a result of an advanced CFD analysis, or you use some kind of an approximate solution that considers a wind environment and a building archetype?

How do you ev aluate the resistance of the building component? Is it a deterministic or a probabilistic analysis?

What happens to the components that become windborne? Do you want to keep track of them afterward?

I need this information to be able to answer your question on how to implement these features in R2D.

Adam