Element 2 - Field Investigations
Project Manager: G.G. Schierle - University of Southern California
The Northridge Earthquake subjected many thousands of wood buildings to moderately intense ground shaking and thus produced an immense amount of valuable data on their seismic behavior. Although some efforts to gather and interpret this data have been made, most notably by the City of Los Angeles, the California Seismic Safety Commission, the Earthquake Engineering Research Institute, and the National Association of Home Builders, only a small fraction of the available data have been collected and interpreted.
This element's task will provide the documentation necessary to support the direction of the testing program, and it will also facilitate the development of an engineering and construction community consensus concerning the nature and significance of woodframe seismic vulnerability that will be necessary for the Building Codes and Standards Element to successfully pursue code changes. (see also: Statistical Investigations carried out under the direction of Prof. G.G. Schierle of the University of Southern California.)
In a sense, the Northridge Earthquake was a "full-scale" and "fully dynamic" test of thousands of woodframe structures. While significant data have already been collected, the Field Investigations element will allow further exploitation of this information via case studies and more thorough analysis of reported data. The observations of individual engineers who have investigated individual woodframe buildings damaged by the earthquake are only "anecdotal" information until documented, verified, and presented for scrutiny.
The proposed Case Studies effort in this element is designed to inexpensively capture this valuable resource and convert it into a scientific form that can be relied upon to help guide the testing and temper the guidance provided in the Building Codes and Standards Element. We know that the problem is a combination of inadequate design and inadequate construction, but in what cases will simply "building it right" according to current code do the job? In which cases are present techniques still inadequate, even if practice conforms to current code?
• CUREE Report : W-04: Wood Project Case Studies (edited by G.G. Schierle)
• CUREE Report : W-09: Northridge Earthquake Field Investigations: Statistical Analysis of Woodframe Damage