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Earthquakes can generate seismic disturbances that propagate vast distances and trigger landslides that can achieve high-speeds. It remains difficult to identify the co-seismic ground motion of these landslides and their triggering earthquakes. In this paper, we report on the analysis of co-seismic ground motions generated by the initiating fracture and deposition impact of the Tsaoling landslide. The landslide, with a source volume of 125 × 10 6 m 3 , was triggered by the 1999 Chi-Chi earthquake in Taiwan. The ground motion was recorded by a strong ground motion station, CHY080, near the scar area. The polarization of the seismic waves indicates that the peak acceleration was parallel to the dip direction. Modified ensemble empirical mode decomposition (EEMD), with additional clustering analysis, was applied to decompose the seismic signals. Two instances were found in the seismic records of a series of peculiar wave packets, with the first being associated with the landslide initiation and the second the landslide impact on the deposit valley. To confirm the first landslide breakage, the decomposed signals were compared with the predictions of the analytic elastic wave model and Newmark analysis. The landslide impact was verified with a computational fluid dynamic simulation. Comparison between the EEMD decomposed signals, elastic wave theory, Newmark rigid body analysis, and numerical simulation demonstrates the claimed landslide motion. [ABSTRACT FROM AUTHOR]

This paper presents an update of the Hyperbolic Function (HBF) method to evaluate the liquefaction potential of sandy soils. The HBF method was created after the 1999 Chi-Chi, Taiwan Earthquake (M w = 7.6) using the database of case histories developed based on field observations and in situ and laboratory tests in areas affected by the 1999 event. The updated HBF method reported herein reflects the 20-year efforts of research and practice in Taiwan after the 1999 event. Here, the original database created by Hwang and his co-workers was first re-examined and updated. The updated Chi-Chi database was supplemented with the cases derived from the 2016 Meinong, Taiwan Earthquake, and some selected data from other parts of the world. This new database was then used to update the parameters of the HBF model through rigorous statistical methods. The HBF model is unbiased (as it corresponds to a probability of 50%). The updated HBF method, a deterministic model, is further extended into a probabilistic version through rigorous statistical calibration. This probabilistic version is expressed as a mapping function that relates the factor of safety (F S) against liquefaction to the probability of liquefaction (P L). The design recommendation for engineering practice in Taiwan is provided based on the calibrated P L - FS mapping function. The updated HBF method is demonstrated through examples to be an easy-to-use procedure for liquefaction potential evaluation. Use of Bayes' theorem for updating the liquefaction probability and the new concept of liquefaction likelihood ratio are also discussed. • An updated database of liquefaction and non-liquefaction cases from Taiwan is created. • An easy-to-use HBF model for liquefaction evaluation is presented, which emerged from two decades of research in Taiwan. • Procedures for the calibration of empirical models for liquefaction evaluation are introduced and illustrated. • The concept of the liquefaction likelihood ratio (LR) is presented with a graph of LR contour curves for Bayesian updating. [ABSTRACT FROM AUTHOR]