NEHRP Clearinghouse
- Title
- Seismic Performance of an Instrumented Six-Story Steel Building.
- File
- PB93114809.pdf
- Author(s)
- Anderson, J. C.; Bertero, V. V.
- Source
- National Science Foundation, Washington, DC., November 1991, 148 p.
- Identifying Number(s)
- UCB/EERC-91/11
- Abstract
- The study investigates the seismic performance of a six-story steel building instrumented with thirteen accelerometers at the time of the Whittier Narrows earthquake (October, 1987). The lateral force system is a moment-resistant perimeter frame. The building was not severely tested by the motions recorded at its base during the earthquake. The dynamic seismic response was entirely linear elastic. System identification techniques are used to identify the periods of vibration from the recorded response. Recorded data are also used to evaluate the contribution of gravity, framing, and nonstructural components to the dynamic properties. A detailed stress check of all members is performed for the design loading. Using a three-dimensional elastic model of the structure, the directional effects are shown to increase the stress in the critical members by 9%. Static nonlinear analyses are used to identify the potential failure mechanism and regions of increased ductility demand, and show that the structure has an overstrength which resulted in an ultimate lateral resistance more than 20% over the code required strength. Nonlinear dynamic analyses are used to evaluate the behavior of the building under stronger motions which have recently been recorded on similar sites. The value of Rw for the moment-resistant frame is shown to vary between 5.6 and 7.4, well below the value of 12 specified in the 1985 UBC.
- Keywords
- Structural vibration; Steel structures; Whittier Narrows Earthquake; Failure; Earthquake damage; Dynamic response; Earthquake engineering; Earthquakes; Vibration damping; Stress analysis; Nonlinear systems; Seismic effects; Ductility; Building codes