The Project involved detailed spatial analysis of experimental wind data to develop GIS mapping of wind design parameters for the International Building Code and ASCE-7. Consistent with the requirements of the International Building Code and intent of the ASCE-7 standard, customized wind design factors were developed from site-specific wind-tunnel test data for:
 
1) Specification of  topographic effects factor Kzt
 
2) Directionality weighting, Kd, in consideration of the probability of critical windspeed
 
3) Mapping of Exposure Categories for determination of Kz , exposure coefficient.
 
A risk-consistent level of protection for hurricane hazard can thus be achieved in structural design of new buildings in the City and County of Honolulu.
 
This work also included the drafting of the Honolulu Building Code Structural Wind Provision amendments in the City’s code adoption ordinance.

Wind Design Mapping For Use in the City & County of Honolulu Building Code

Adoption of a 2003 Model Building Code, Incorporating New Wind Design:

This project entailed the preparation of a comprehensive wind study for adoption of an update to the City and County of Honolulu Building Code using the amendments to the International Building Code (IBC) 2003 provisions to make improvements in building safety and incorporate a new generation of design windspeed mapping. The project has undertaken new wind speed design mapping and technical provisions to enable the adoption of the International Building Code and ASCE-7 standard by the City and County of Honolulu, which is located within a hurricane  hazard region.

Several necessary technical modifications were introduced so that state-of-the-art research results can be used in design and retrofit applications in a manner that completely addresses the requirements of the International Building Code.  As the successor to the Uniform Building Code, the IBC introduced an ASCE-7 topographic factor, Kt, which in its current generic specification does not give accurate results nor can it be applied with consistency in the complex topography of Hawaii.
 
The ASCE-7 standard also requires a directionality factor, Kd.  It had been based on flat terrain conditions without orographic channeling of wind, so modifications were necessary.  Implementation of the ASCE wind standard in Hawaii required a GIS-based evaluation of the Kt and Kd wind directionality terms.