Measurement of Wind Effects on a Kilometer-Level Cable-Stayed Bridge during Typhoon Haikui

Abstract

Because of the significant position of long-span cable-supported bridges in land transportation, the typhoon wind effects on these slender structures attract intensive attention in engineering communities. This paper presents a study about the wind effects on a kilometer-level cable-stayed bridge during Typhoon Haikui. The Sutong Cable-Stayed Bridge (SCB) with a main span of 1,88 m is taken as the research object and the structural health monitoring system (SHMS) works as a medium to provide valuable full-scale measured data. The wind characteristics, e.g., turbulence intensity, gust factor, turbulence integral scale, and power spectral density (PSD), of the severe typhoon are firstly analyzed in a statistical point of view. Specifically, the variation of turbulence PSDs in different stages is described and compared among cases at different altitudes. Then, the dynamic properties of the structure are identified with the random decrement technique, and the amplitude-dependent features are discussed. Moreover, the relationship between structural dynamic responses and the wind velocity is analyzed with a comparison to the results from the wind tunnel test. Since a significant variability is captured in structural buffeting responses, the response surface methodology (RSM) is employed to investigate influential variables in a statistical framework, which is further utilized to predict the wind-induced dynamic responses considering the variability. The observations and findings are expected to provide references for the wind-resistant analysis and design of super-long-span cable-stayed bridges.