Neural Network-Based Equations for Predicting PGA and PGV in Texas, Oklahoma, and Kansas

TL;DR

This study develops and validates neural network models tailored for predicting ground motion parameters in Texas, Oklahoma, and Kansas, regions with increased seismic activity, offering improved accuracy over existing models.

Contribution

The paper introduces region-specific ANN-based attenuation models for PGA and PGV, converted into simple equations for practical engineering use, addressing limitations of existing models in CENA.

Findings

ANN models outperform existing models in accuracy

Models are applicable to low-distance and soft soil conditions

Sensitivity analysis identifies key predictive parameters

Abstract

Parts of Texas, Oklahoma, and Kansas have experienced increased rates of seismicity in recent years, providing new datasets of earthquake recordings to develop ground motion prediction models for this particular region of the Central and Eastern North America (CENA). This paper outlines a framework for using Artificial Neural Networks (ANNs) to develop attenuation models from the ground motion recordings in this region. While attenuation models exist for the CENA, concerns over the increased rate of seismicity in this region necessitate investigation of ground motions prediction models particular to these states. To do so, an ANN-based framework is proposed to predict peak ground acceleration (PGA) and peak ground velocity (PGV) given magnitude, earthquake source-to-site distance, and shear wave velocity. In this framework, approximately 4,500 ground motions with magnitude greater than 3.0 recorded in these three states (Texas, Oklahoma, and Kansas) since 2005 are considered. Results from this study suggest that existing ground motion prediction models developed for CENA do not accurately predict the ground motion intensity measures for earthquakes in this region, especially for those with low source-to-site distances or on very soft soil conditions. The proposed ANN models provide much more accurate prediction of the ground motion intensity measures at all distances and magnitudes. The proposed ANN models are also converted to relatively simple mathematical equations so that engineers can easily use them to predict the ground motion intensity measures for future events. Finally, through a sensitivity analysis, the contributions of the predictive parameters to the prediction of the considered intensity measures are investigated.