Simplified Liquefaction Prediction and Assessment Method Considering Waveforms and Durations of Earthquakes

Abstract

This paper presents a new simplified liquefaction prediction and assessment method that is capable of considering the influence of the waveforms and durations of earthquakes. The concept of an effective number of waves was introduced to represent the characteristics of the irregularity of waveforms and the different number of load cycles of irregular seismic motions, as well as their influence on the occurrence of liquefaction. A comprehensive set of laboratory liquefaction tests and statistical analyses were performed to study and validate this concept. The validity of the proposed method, which adopts a wave correction coefficient based on the proposed concept, was verified using the case histories of five past major earthquakes, demonstrating that the predictive capability of the new method was improved compared with that of the conventional method for the cases of liquefaction and no liquefaction. A unique feature of the new simplified method is its universality, allowing it to be applied to various types of liquefaction charts, facilitating more-rational liquefaction prediction and assessment worldwide.