Seismic ground response at Lotung (Taiwan)

In this paper the ground response of the Lotung experiment site during the strongmotion LSST7 occurred on May 1986 is simulated using two different numerical schemes: a simple equivalent-linear visco-elastic and a fully-coupled non-linear approach. The fullycoupled includes an advanced elasto-plastic soil model which has been calibrated against resonant column data and in-situ cross-hole measurements. The two horizontal components of the input motion are applied separately at bedrock level. The results of the simple and advanced numerical simulations are compared with the down-hole motions recorded in-situ during the investigated seismic event in terms of acceleration time histories and response spectra. The comparison between predicted results and in-situ measurements highlights the limitations of the frequency-domain approach and demonstrates the good performance of the advanced numerical scheme. Further investigation is needed to improve the numerical predictions of the observed ground response, in particular the peak ground acceleration in the N-S direction.