NEHRP Clearinghouse

Title
Implementation of Base Isolation for the Foothill Communities Law and Justice Center.
File
PB85152155.pdf
Author(s)
Tarics, A. G.; Way, D.; Kelly, J. M.
Source
National Science Foundation, Washington, DC., November 1984, 300 p.
Abstract
Base isolation, an approach to seismic structural design, is discussed, and its use in the design of the Foothill Communities Law & Justice Center (FCLJC) in Rancho Cucamonga, California, is described. FCLJC's design parameters are noted: it was designed for an 8.3 Richter event on the San Andreas Fault, with all structural members remaining in the elastic range and all functions remaining operational after the event. Additionally, because all the significant earthquake motion is concentrated at the bearings rather than encompassing hundreds of columns, beams, and walls, the overall system is more predictable. The base-isolated design resulted in a savings of $1 million in structural steel in comparison with the conventional steel frame that had been employed in a preliminary design. Finally, when compared to the preliminary design, the base isolated design exhibited a reduction of forces transmitted into the building by a factor of up to seven. Construction details are supplied, and appendices contain a technical report on design of bearings, computer plots from time history analyses, construction costs, fabrication descriptions, and a draft of the code for base isolation design of buildings.
Keywords
Buildings; Bearings; Earthquake engineering; Earthquake resistant structures; Base isolation; Graphs (Charts); Computer aided testing; Construction; Design; Dynamic structural analysis