000012250 001__ 12250
000012250 005__ 20141205160035.0
000012250 04107 $$aeng
000012250 046__ $$k2008-10-12
000012250 100__ $$aYuan, Xiaoming
000012250 24500 $$aA New Method for Fast Identification of Liquefied-Soil Site from Surface Acceleration Records

000012250 24630 $$n14.$$pProceedings of the 14th World Conference on Earthquake Engineering
000012250 260__ $$b
000012250 506__ $$arestricted
000012250 520__ $$2eng$$aThe methods for detection of soil liquefaction from seismic records are being developed recently. The developed detection methods make it possible to capture the alteration of the surface ground accelerations and then the occurrence of soil liquefaction can be indicated immediately after a earthquake happens. This kind of technique is useful in developing a system of seismic motion monitoring and the real-time disaster mitigation, and also provides a new approach to understand the mechanism of liquefaction. However, the existing detection methods generally result from the empirical estimation and there is shortage of the theoretical models. As a result, the soft sites by the methods are easily misdetected as the liquefaction sites and the misdetection have been explained reasonably. In the paper a new method for fast identification of the liquefied-soil site from surface acceleration records is presented in terms of the concept of the frequency decrease rate. By analyzing the main factors influencing the self-vibration period in the liquefied sites the frequency decrease rate is employed to describe the variation of the acceleration history during the liquefaction. The liquefiable site is simplified as a double-degree-freedom model and the formula for calculating the reduction of horizontal natural frequency induced by liquefaction is attained. And then the lower limit of frequency decrease rate is derived and based on it, the fast identification method of site liquefaction from surface acceleration records is proposed. The reliability of the method is examined by the actual earthquake records and the results indicate that by using the approach presented in the paper, not only the liquefied sites and the stiff non-liquefied sites are identified, but also the soft non-liquefied sites are detected correctly.

000012250 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000012250 653__ $$aAcceleration records, liquefaction identification, model, frequency decrease rate

000012250 7112_ $$a14th World Conference on Earthquake Engineering$$cBejing (CN)$$d2008-10-12 / 2008-10-17$$gWCEE15
000012250 720__ $$aYuan, Xiaoming$$iSun, Rui
000012250 8560_ $$ffischerc@itam.cas.cz
000012250 8564_ $$s197770$$uhttps://invenio.itam.cas.cz/record/12250/files/04-02-0091.pdf$$yOriginal version of the author's contribution as presented on CD, Paper ID: 04-02-0091.
000012250 962__ $$r9324
000012250 980__ $$aPAPER