# Structural Responses of a Superall Building Subjected to a Severe Typhoon at Landfall
## 1 Introduction  
There is a fast development of high-rise buildings at coastal areas where tropical cyclones (TCs) may attack frequently [1]. As these buildings are commonly characterized by low natural frequencies and high flexibilities, they become considerably sensitive to wind load [2]. In light of the significance of wind effects on the safety and the serviceability of such skyscrapers, continuous efforts have been made on this topic via different methods, such as wind tunnel tests and numerical simulation [3; 4; 5; 6; 7]. However, due to the complexity of involved issues, field study is generally regarded as the most credible way for such investigations at present. During the last decades, numerous filed studies on dynamic performance of high-rise buildings under wind action have been conducted [8; 9; 10; 11; 12; 13; 14]. Among these works, [PERSON], et al. established structural health monitoring (SHM) systems on four skyscrapers in Chicago and Dubai and analyzed the structure dynamic properties and the associated wind effect based on collected records [15; 16; 17]. [PERSON] et al. measured the wind-induced vibration response of a 79-story tower during the passage of several typhoons [18]. [PERSON] et al. analyzed wind characteristics and wind effects on super-tall buildingsbased on field records from the SHMs of three towers [19; 20]. [PERSON] et al. employed the fast Bayesian frequency domain method to observe the modal characteristics of two high-rise buildings under the action of typhoon [21]. [PERSON] et al. analyzed the dynamic properties of a 492 m high building, and the functional performance of affiliated active-tuned-mass-damper (ATMD) system was examined [22; 23]. [PERSON] and his team explored the wind-induced responses of several super-tall buildings at coastal areas. Results from field measurements were further used to verify the validity of wind tunnel testing techniques [24; 25; 26; 27]. [PERSON] et al. and [PERSON] et al., among others, also analyzed the dynamic characteristics and the wind-induced response of high-rise buildings [28; 29]. Undoubtedly, the aforementioned studies provide useful insights for further understanding the characteristics of structural dynamics of high-rise buildings. However, a majority of these investigations were based on field records collected at a single height level, while those based on multi-levels of records have been comparatively less reported. The reason mainly lies in that field measurement at multiple height levels of a high-rise building is much more challenging and costly than the one at a single level. Typically, not only considerably more devices are required, but also the output signals from varied devices should be synchronized and collected with a uniform format. However, studies based on multi-levels of records are of great practical interests, since they have overwhelming advantages against those based on a single level of records. First, they can provide more information of the building structure (e.g., mode shape), and such information is significantly useful for many relevant studies and practices such as updating finite-element (FE) models and correcting wind tunnel test results. Second, results based on multi-levels of records are usually regarded as more accurate and credible than those associated with a single level of records, as more measurement information and more robust methods/algorithm are utilized [30]. During 15-18 September 2018, Typhoon Mangkhut got close to and made landfall on the south coast of China at a severe-typhoon intensity level and exerted severe impact on Guangzhou. During this period, the SHM system installed on a 303 m high-rise building at Guangzhou worked smoothly, and field records at nine height levels of the building were collected successfully. This study focuses on the structural responses of this skyscraper with a primary objective of further understanding the dynamic properties of and the typhoon effects on this building based on multi-levels of field measurements.