弧形切角三角形超高层建筑风荷载体型系数研究

Study on Wind Load Shape Coefficient of Curved Tangential Triangle High-Rise Buildings

以大连绿地中心项目为工程背景,基于Fluent软件对弧形切角三角形超高层建筑进行风荷载数值模拟研究。首先对CAARC高层建筑标准模型进行模拟合理性分析验证。然后在0˚风向角来流下分析该建筑的风压分布和体型系数分布规律,并与我国荷载规范给出的截角三角形平面体型系数值进行比较分析。结果表明:结构主迎风面为正风压,其余面均为负风压;结构体型系数总体上随着建筑结构高度变化规律增加而逐渐增大,但在0.3 H高度时的弧形凹角处出现最大负值,局部体型系数发生突变;对于弧形切角三角形超高层建筑,由于次迎风面弧形凹角处产生了较强的分离流和涡脱过程,导致此处的体型系数为较大的负值,与规范取值有较大差别,其余面模拟结果均与规范相近,在结构设计时应注意此处取值影响。

A numerical simulation study of wind loads on a curved tangential triangle super high-rise building was conducted using Fluent software,with the Dalian Greenland Center project serving as the engineering context.The study began by validating the simulation’s methodology and parameters through a rationality analysis using the CAARC tall building standard model.Subsequently,the wind pressure distribution and shape coefficient distribution were analyzed under an incoming flow at a 0˚wind direction.These results were then compared with the shape coefficient values for truncated triangular plan shapes as specified in the Chinese load codes.The findings indicate that the primary windward face of the structure experiences positive wind pressure,while the remaining faces experience negative wind pressure.The shape coefficient generally increases with building height but exhibits a maximum negative value at the curved concave corner at 0.3 H height,where a local abrupt change in the shape coefficient is observed.For curved-chamfered triangular supertall buildings,the presence of strong flow separation and vortex shedding at the concave corner on the sec-ondary windward face results in a significantly negative shape coefficient in this region,which differs markedly from the values specified in the codes.The simulation results for the other faces are generally consistent with the standards.These discrepancies should be carefully considered during structural design.