Field Measurement Research On The Near-ground Wind Characteristics And Wind Effect Of Super High-rise Building During Strong Winds In Urban Areas

With the acceleration of urbanization and the emergence of extreme climates,the increasingly complex wind environment in urban areas and the more sensitive wind effects of super high-rise buildings have occurred during the invasion of strong typhoons.It is necessary to improve further and deepen the issues:changes in the characteristics of the near-ground wind field,the non-stationary characteristics of strong hurricanes,the interference effects of local micro-topography on measured meteorological wind speed,the wind-induced vibration response of super high-rise buildings,and the characteristics of structural modal parameters,as well as the reasonable value of the reference wind speed in the comparison and verification of wind tunnel test versus field measurement.Based on the meteorological data of wind stations in Shenzhen during Super Typhoon Mangkhut,the urban near-ground wind characteristics and the wind effects of super high-rise buildings are studied based on typhoon wind field simulation,field measurements,and wind tunnel experiments,as well as computational fluid dynamics numerical simulation in this thesis.The main work and achievements are as follows:(1)The historical wind speed data of Shenzhen meteorological gradient tower during Super Typhoon Mangkhut were analyzed.It indicates that for the landform with dense and high vegetation upstream,the mean wind speed profile agrees with Category C terrain,and the specification result tends to be conservative.The turbulent intensity profile is in line with Category D terrain,and the turbulence integral scale profile is consistent with the recommended value of the Japanese Code.The results provide a reference for the terrain roughness value in the wind-resistant design of super high-rise buildings.(2)The three meteorological observation stations in Shenzhen are affected by surrounding influence factors.The influence of surrounding conditions on the observed wind speed was studied by wind tunnel test and numerical simulation method,and then quantitatively described by the wind speed influence coefficient.According to the analysis and conversion of the wind speed influence coefficient,each station’s maximum standard wind pressures during Mangkhut were 0.53k Pa,0.51k Pa and 0.50k Pa,respectively.The results of this paper can provide a correction basis for determining the expected wind speed in Shenzhen during the subsequent typhoons.(3)The measured wind-induced response of several super high-rise buildings(SHBs)in the Pearl River Delta during Super Typhoon Mangkhut was analyzed and refined.The results show that the maximum wind-induced peak acceleration of SHBs with different heights,planes and elevation shapes are distributed between 13.2 and 43.0 cm/s~2.The minimum peak acceleration responses appeared at the 350m high Tower 7 in One Shenzhen Bay,while the maximum appeared in another apartment with a height of about 200m.It is noteworthy that the wind-induced response of smaller residential SHBs is more sensitive than taller commercial office ones.(4)The revised maximum wind speed,good upstream terrain roughness and parameter identification results of measured signals were used to reanalyze the wind tunnel data.The calculated values agree well with the measured ones,which verify the reliability of the previous wind tunnel test.It also implies that the good upstream terrain roughness is the predominant factor that affects the consistency between the wind tunnel test and the measured test.(5)By analyzing the wind effect characteristics of the SHBs and the corresponding wind tunnel test data,it is found that the reasonable orientation is one of the main factors affecting the wind resistance performance of the SHBs.For SHBs with general rectangular planes,it should be avoided the narrow side facing the dominant and strong wind direction of engineering site,which could obviously reduce the wind-induced response of structure.