Data-driven Accelerogram Synthesis using Deep Generative Models
This work provides a method for on-demand synthesis of accelerograms, which is crucial for engineers needing robust ground motion estimations for various applications, especially in conditions where no earthquake recordings exist.
This paper addresses the challenge of estimating ground motions from scenario earthquakes by developing a deep generative model based on Generative Adversarial Networks (GANs). The model synthesizes realistic 3-Component accelerograms conditioned on magnitude, distance, and Vs30, capturing statistical features like acceleration spectra, waveform envelopes, and consistent Peak Ground Acceleration (PGA) estimates.
Robust estimation of ground motions generated by scenario earthquakes is critical for many engineering applications. We leverage recent advances in Generative Adversarial Networks (GANs) to develop a new framework for synthesizing earthquake acceleration time histories. Our approach extends the Wasserstein GAN formulation to allow for the generation of ground-motions conditioned on a set of continuous physical variables. Our model is trained to approximate the intrinsic probability distribution of a massive set of strong-motion recordings from Japan. We show that the trained generator model can synthesize realistic 3-Component accelerograms conditioned on magnitude, distance, and $V_{s30}$. Our model captures the expected statistical features of the acceleration spectra and waveform envelopes. The output seismograms display clear P and S-wave arrivals with the appropriate energy content and relative onset timing. The synthesized Peak Ground Acceleration (PGA) estimates are also consistent with observations. We develop a set of metrics that allow us to assess the training process's stability and tune model hyperparameters. We further show that the trained generator network can interpolate to conditions where no earthquake ground motion recordings exist. Our approach allows the on-demand synthesis of accelerograms for engineering purposes.