Earthquake Engineering

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The National Center for Research on Earthquake Engineering (NCREE) of NARLabs is equipped with a tri-axial shaking table, an L-shape reaction wall system, and a large strong floor test bed, allowing earthquake engineering simulations of structural components or systems in full-scale. To develop the necessary technologies to withstand near-fault earthquakes, NCREE started to construct a high-speed long-stroke shaking table system in the new laboratory located at the Gueiren campus of National Chen-Kung University, Tainan, in 2014. The new shaking table system and laboratory started operating in August 2017. NCREE links researchers and practicing professionals to build interdisciplinary knowledge and expertise using a variety of computational and experimental facilities in earthquake-related fields. Thus, NCREE engages in basic and applied researches that resolve critical seismic engineering issues. Following the need for pre-earthquake preparedness, emergency response, and post-earthquake recovery, the center brings together national academic resources, implements integrated research projects and develops enabling technologies for earthquake hazard mitigation. The importance of seismic safety is also recognized for energy facilities. Since 2021, NCREE has planned a new Green Energy Laboratory to serve as a world-class seismic-related testing facility. By improving offshore wind turbines and geotechnical R&D and testing capabilities, the laboratory will support the government’s efforts to achieve environmental sustainability.

Seismic Design Code and Commentary for Buildings

"Seismic Design Code and Commentary for Buildings" is critical to the earthquake-resistant level of the overall project, and its rationality also has a huge effect on the economic level. Therefore, the drafting of codes and regulations that have both seismic resistance and economic benefits is the goal of code research. Since 1974, Taiwan has established seismic design regulations, and has continued to refer to research results and foreign seismic design codes to keep the code moving with the times. Especially after the 921 earthquake, there are a lot of resources in earthquake-resistant technology research, and relevant regulations and codes have also changed with each passing day.  NCREE gathers the research results and suggestions of the engineering and academia on the seismic design code, conducts corresponding research and proposes relevant draft revision suggestions, and convenes representatives from industry, government, academia, and research to form a code research and development committee to discuss proposals and reach revisions regularly. After the consensus is reached, it will be sent to the competent authority for deliberation, and be published. The content of the code will be revised to make the seismic design code more complete and reasonable.

Bridges Study

Based on the purposes of extending the service time of existing bridges, reducing construction timeline, decreasing environmental impact, improving construction safety, reducing life-cycle costs, and enhancing the specifications, the main research tasks of the bridge engineering division are to carry out research and development of bridge seismic and lifespan extension technology, as well as the development and enhance of specifications and technical guidelines, provide new bridges with safe, seismic, fast, and economical bridge structure systems, and improve the safety, disaster prevention, and management technology of old bridges. 

Geotechnical Study

NCREE constantly maintains the ground motion and site characteristics database to develop the ground motion models (GMM) of Taiwan and semi-empirical simulation schemes. As for the geotechnical engineering research field, various types of geotechnical testing technologies together with associated facilities have been built, including shaking table tests using a large-scale biaxial laminar shear box, field tests, numerical simulations, and dynamic soil property tests for studying key issues related to pipelines, shallow foundations, harbors, piers, bridge foundations, and offshore wind turbines, etc. We also develop evaluation methods for soil liquefaction and potential assessment, and build a geotechnical database to construct the soil liquefaction potential map of Taiwan.

Research on Nonstructural Components and Systems

To reduce the safety concerns, economic impact and functional loss of important buildings caused by seismic damages of mechanical or electrical equipment or related nonstructural components, the research goals of the Nonstructural Components and Systems (NCS) Division are to promote seismic performance qualification facility and to develop seismic evaluation and strengthening strategies for critical NCS. Recent highlighted core research of the NCS Division is the seismic improvement strategies for critical energy or livelihood industries. 

Earthquake Early Warning System (EEWS)

The on-site EEW technique takes advantage of the different propagating velocities of P- and S-waves of earthquakes. It detects the faster but typically non-destructive P-wave and by using AI algorithms estimates the intensity of the slower but imminent S-wave which might be more destructive. If the predicted intensity exceeds a certain threshold, the system issues warning messages that can be used in various ways to reduce possible loss in the upcoming seismic event. Compared to the regional EEWS provided by the Central Weather Bureau, the on-site EEWS typically provides longer warning time because it detects P-wave detection and predicts S-wave in only a single sensing station. The composite EEWS integrates both the services of the regional and on-site EEWS to provide fast and accurate earthquake warning.

Innovation and application of seismic isolation and energy dissipation technologies

Seismic isolation and energy dissipation technologies have been recognized as effective methods for earthquake hazard mitigation to building structures and civil infrastructures. Current research topics focus on simultaneously optimizing the displacement and acceleration responses while the structures are subjected to excitations with abundant long-period components or near-fault earthquakes. The implementation of adaptive passive or semi-active control technologies to isolation and damping systems is also an important research target.

Smart Structures

Smart structures integrate using advanced sensing and control technologies to protect structures, and important equipment and components in structures as well. For structural control, recent advancements have been centered on establishing effective semi-active or active control strategies with new control devices (e.g., nonlinear energy sinks and geometrically nonlinear damping systems) that can further improve structural performance against critical seismic events (e.g., near-fault or long period earthquakes). As to structural health monitoring, recent research is directed to the deployment of advanced sensing technologies, the development of state-of-the-art monitoring and damage detection methods (e.g., artificial intelligence) to provide fast estimation of structural health after or even during seismic events.

Seismic Risk Assessment and Disaster Management

Recent research focuses on the following topics.

(1) The Taiwan Earthquake Loss Estimation System is upgraded with open-source GIS tools. It can reasonably assess the amount and the distribution of damages and losses, including buildings, bridges, water systems, etc., and the rescue demand of various kinds under any given seismic scenarios. 
(2) Early Seismic Loss Estimation technology. Early estimation results can reach emergency response agencies promptly through SMS, Email, or the information website.
(3) The Probabilistic Seismic Risk Assessment Model integrates the seismic disaster simulation techniques and the seismic source models around Taiwan.
(4) A rescue route planning methodology is proposed to connect cities and counties around Taiwan by collating the road network data and the distributions of buildings, bridges, populations, and rescue suppliers, considering road hierarchy and connectivity between crucial nodes. The risk of road blockage due to roadside building collapse or in-route bridge damage can be assessed to provide information for alternate route planning and the seismic improvement of old buildings.
(5) Studies on emergency medical care seismic resilience. It is applied to examine different patient diversion strategies and improve the region's overall emergency medical care performance.
(6) Earthquake disaster reduction and emergency response cloud services. In the future, NCREE will enable online services of seismic loss estimation and incorporate them with a 3D GIS platform to improve user experience and visual effects.