000018918 001__ 18918
000018918 005__ 20170118182247.0
000018918 04107 $$aeng
000018918 046__ $$k2017-01-09
000018918 100__ $$aCheng, Chin-Tung
000018918 24500 $$aSeismic Performance of Rocking Base-Isolated Structures Subjected To Biaxial Earthquake Loads

000018918 24630 $$n16.$$pProceedings of the 16th World Conference on Earthquake Engineering
000018918 260__ $$b
000018918 506__ $$arestricted
000018918 520__ $$2eng$$aLiteratures have showed that traditional sliding base-isolated systems may have long-period resonant-like response induced by a ground motion containing strong long-period frequency spectra. In this paper, a new type of isolator called variablefrequency rocking bearing is proposed. The system allows the bearing remain still under a moderate seismic load but start to rock back-and-forth during severe earthquakes. And the vibration is damped throughout each impact of the bearing on structural footing or foundation surfaces. Based on the force-displacement relation and analytical damping of the system, seismic response of the structure may be estimated through a modified elastic response spectrum. The objective of the paper is to investigate seismic performance of this base-isolated structure subjected to bi-axial earthquake loads. To validate proposed idea, a one-bay-one-story spaced structure base-isolated with rocking bearings was constructed. In total, 236 shaking table tests were conducted with various investigated parameters including aspect ratio of bearings, the shape of rocking plates (plane or polynomial), bi-directional earthquakes and waveforms of ground motion. Test results indicate that vibration behavior was nonlinear with respect to rocking amplitude. And structural response of the structure excited by bihorizontal earthquakes is the largest, followed by uni-axial and then bi-directional with horizontal plus vertical earthquakes. Due to the restrain of spring force at rocking interface, seismic response of structures excited by bi-directional with horizontal plus vertical earthquakes is found similar to those excited by uni-axial earthquakes. It is also found that seismic response is increased with the increase of aspect ratio of bearings, while the effect of rocking surface is marginal. Without any damage incurred under earthquakes, radiation damping of rocking systems is found less than 4% for all tests.

000018918 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000018918 653__ $$aRocking Bearing; Base-isolation; Damping Ratio; Shaking Table Tests.

000018918 7112_ $$a16th World Conference on Earthquake Engineering$$cSantiago (CL)$$d2017-01-09 / 2017-01-13$$gWCEE16
000018918 720__ $$aCheng, Chin-Tung$$iKang, Wei-Zhe
000018918 8560_ $$ffischerc@itam.cas.cz
000018918 8564_ $$s929184$$uhttps://invenio.itam.cas.cz/record/18918/files/248.pdf$$yOriginal version of the author's contribution as presented on USB, paper 248.
000018918 962__ $$r16048
000018918 980__ $$aPAPER