New Equations to Evaluate Lateral Displacement Caused by Liquefaction Using the Response Surface Method

Few empirical and semi-empirical approaches have considered the influence of the geology, tectonic source, causative fault type, and frequency content of earthquake motion on lateral displacement caused by liquefaction (DH). This paper aims to address this gap in the literature by adding an earthquake parameter of the standardized cumulative absolute velocity (CAV5) to the original dataset for analyzing. Furthermore, the complex influence of fine content in the liquefiable layer (F15) is analyzed by deriving two different equations: the first one is for the whole range of parameters, and the second one is for a limited range of F15 values under 28% in order to the F15’s critical value presented in literature. The new response surface method (RSM) approach is applied on the basis of the artificial neural network (ANN) model to develop two new equations. Moreover, to illustrate the capability and efficiency of the developed models, the results of the RSM models are examined by comparing them with an additional three available models using data from the Chi-Chi earthquake sites that were not used for developing the models in this study. In conclusion, the RSM provides a capable tool to evaluate the liquefaction phenomenon, and the results fully justify the complex effect of different values of F15.