NEHRP Clearinghouse

Title
Experimental Investigation of Primary-Secondary System Interaction.
File
PB89122204.pdf
Author(s)
Manolis, G. D.; Juhn, G.; Reinhorn, A. M.
Source
National Science Foundation, Washington, DC., May 27, 1988, 56 p.
Identifying Number(s)
NCEER-88-0019
Abstract
A series of experiments were conducted on an earthquake simulator, whereby single degree-of-freedom pendulums (dampers) representing a secondary system were attached to the floor of a scaled, three-story frame representing the primary structure. The dampers had mass ratios ranging from one-tenth to one-hundredth with respect to the mass of the story they were attached to. Both tuned and de-tuned cases were examined. Two types of excitations were imparted from the earthquake simulator to the frame with an attached damper, namely, white noise for identification purposes and the El Centro 1940 accelerogram. The results of these tests are grouped into transfer functions resulting from the white noise excitation and time histories resulting from the El Centro 1940 accelerogram. These results are followed by interpretations using numerical techniques developed previously for this purpose. Good correlation between the experimental evidence and the theoretical predictions is obtained, which points to that fact that interaction between primary and secondary systems does occur and can be detected.
Keywords
; Simulators; Earthquake resistant structures; White noise; Damping; Seismology; Graphs (Charts); Secondary waves; Primary waves; Soil dynamics; Seismic effects; Dynamic structural analysis