Progress of the Twin-ER project: pilot digital twin for earthquake risk

We present the progress of the project Twin-ER: Pilot Digital Twin for Earthquake Risk. The goal of the project is the integration of digital models of the city and the Earth into the structure of a digital twin, focused on seismic risk.

The Earth model includes the generation of new seismic source models based on maps correlating surface deformation and seismic activity rates. Deformation maps will be determined through the analysis of GNSS time series and InSAR images for several dates. Seismic activity rates will be calculated by combining statistical analyses of the seismic catalog with mechanical analyses of earthquake-related stress changes in the crust. The derived maps will show location-, magnitude-, and time-dependent activity rates. Seismic source models will form the basis for the development of seismic hazard maps and constitute the main component of the Earth model.

The city model integrates innovative exposure models based on Cadastral data, enhanced with machine learning and deep learning algorithms to identify building typologies and their seismic vulnerability. These analyses will incorporate data of different nature, such as cadastral reference value or exposure time to high temperatures, with the aim of extending the exposure to a multi-hazard and multi-risk context. The exposure and vulnerability models constitute the main component of the city model.

By combining seismic hazard models on one hand, and exposure and vulnerability models on the other, the seismic risk model will be obtained. This model represents the expected damage and losses in a city in the event of an earthquake. Therefore, it is a crucial piece of information for proposing risk mitigation measures and planning emergency response.

Both Earth and city models are embebed into the digital twin seismic risk. This digital twin is conceived in a pilot phase. The model will be fed with the results of risk simulations, which can be visualized in a web environment, leaving aspects of data loading automation from updated sensors or external servers and subsequent simulations with that updated data for future developments.

The project is applied in two study areas of similar size but different, complementary characteristics. One is southeastern Spain, where (1) seismic activity is moderate, and major earthquakes occur rarely, (2) cities have a relatively old building stock and are more vulnerable to earthquakes, and (3) the availability and accessibility to cadastral data are optimal. The other study area is El Salvador, where (1) there is high seismic activity with frequent large earthquakes, (2) cities have a relatively modern building stock with abundant informal construction, and (3) there is no free access to cadastral data.

 The advances presented here include the UML model of the entire digital twin, the seismic activity and deformation maps in SE Spain, and the city 3D models of two scenarios of application.