# Field Research on the Wind-Induced Response of a Super High-Rise Building under Typhoon
## 7 Conclusions  
This paper simultaneously measures the wind characteristics on the roof and the acceleration responses of the 10 th, 18 th, 25 th, 32 nd and 41 st floors of a high-rise building in Wenzhou during the passing of a typhoon between 2014 and 2016. It also analyses the dynamic characteristics and wind-induced response of buildings by using the Welch and improved NExT-ERA methods. The results indicate the following:  
(1) According to the test results, strong typhoons frequently affect Wenzhou. Thus, the wind load mainly controls loads for high-rise building designs in Wenzhou. The measurement results show that the typhoons that occurred in Wenzhou from 2014 to 2016 were dominated by winds from the east, northeast and northwest, with inflow directions that were mainly concentrated in three directions, namely, 0\({}^{\circ}\)-30\({}^{\circ}\), 75\({}^{\circ}\)-105\({}^{\circ}\) and 300\({}^{\circ}\)-360\({}^{\circ}\), respectively.  
(2) The measured acceleration skewness coefficients of Typhoons Chan-hom and Dujuan are close to 0, and their kurtosis coefficients are close to 3, which is consistent with the Gaussian distribution.  
(3) The Welch and NExT-AVG-ERA methods measured the natural vibration frequency difference between the two methods, which reached up to 1.286%, thereby proving the reliability of the NExT-AVG-ERA method. The measured values, except for the torsional mode, are larger than the finite element analysis results, as indicated by a comparison with the calculation results of the finite element model. The first-order natural vibration frequencies of the test building are between 0.390 and 0.409, which is in good agreement with [PERSON]'s prediction results.  
(4) The second-order damping in both directions is the largest for northwesterly typhoons, such as Typhoons Chan-hom and Dujuan. The third-order damping in both directions is the largest when a typhoon, such as Typhoon Dujuan, is easterly. The first-order damping ratios of the three typhoons are less than their corresponding high-order damping test results.  
(5) The damping performance of buildings has obvious nonlinear characteristics, and the structural damping ratio generally shows an increasing trend with the amplitude. The first-, second-, and third-order damping ratios of the structure during Typhoons Chan-hom and Dujuan increase with the peak acceleration, whereas the damping during Typhoon Fung-wong remains almost unchanged.  
(6) The root mean square of the acceleration response of the building structure during Typhoons Chan-hom and Dujuan increases with the wind speed. However, the increase rate of TyphoonChan-hom is small because the angle between the incoming flow and the building is 45\({}^{\circ}\), and because the acceleration response in the downwind and crosswind directions is not obvious. Table 6 shows that the fitting indexes of Typhoon Chan-hom are small, indicating a non-obvious dynamic response from this angle. The fitting indexes of the two directions of Typhoon Dujuan are at the same level, which is up to 1.634. Thus, the crosswind dynamic response should be considered in the design of high-rise buildings.  
(7) The measurement results show that the working environment of the staff at the top of the building under the two typhoons meets comfort requirements.  
[PERSON] conceived, designed, collected and analyzed data, wrote and revised the paper; [PERSON] finalized the manuscript and provided the funding; [PERSON] and [PERSON] contributed in the results and discussions and solution; [PERSON] contributed to the English; [PERSON] and [PERSON] collected and analyzed data.  
This work is financially supported by the National Natural Science Foundation of China with Grant No. 51478179 and No. 51678233.  
The authors declare no conflict of interest.