Wind Load Characteristics And Aerodynamic Optimization Of Large Span Arched Cantilevered Roof

The double-arched cantilevered light steel roof is a typical form of large-span roof structure.This type of building usually has the characteristics of large span,soft structure and light weight.Wind load often plays a controlling role in its structural design.The current domestic and international load codes lack the wind-resistant design criteria for the continuous arched cantilevered roof structure.For this reason,based on computational fluid dynamics theory,the computational fluid dynamics(CFD)numerical simulation method is applied.The wind load characteristics of the arched cantilevered roof structure have been comprehensively studied and discussed.On this basis,according to the principle of aerodynamic optimization,a simple and practical auxiliary wind-proof and pneumatic measures are proposed to improve the wind-resistance of the double-arched cantilevered roof.The contents and results of the specific inquiry are as follows:(1)The numerical simulation method of wind load: When the CFD numerical simulation of the actual flow field is carried out,the simulation accuracy is affected by multiple factors.For this reason,the basic theory of computational fluid mechanics and the solution method of relevant governing equations are carefully combed.The turbulence model is optimized,the analysis parameters are adjusted,the range of the analysis basin is determined,and a suitable finite element analysis model is established.Through the analysis of the simulation results of the standard square cylinder flow and the experimental results,a reasonable numerical simulation method of wind load is established.Give technical advice to ensure the correctness of the subsequent numerical simulation work.(2)Wind load characteristics study: Through the numerical wind tunnel test,the variation law of static wind pressure and pulsating wind pressure of continuous arched cantilevered roof is analyzed.Based on the Reynolds time-average method,the wind pressure distribution characteristics of the roof and the most unfavorable wind angle of attack are explored.On this basis,the large-eddy simulation is used to further study the spectral characteristics,spatial coherence and coherence function of the roof surface.Factors and changing patterns.The research shows that the ventilation rate at the back of the grandstand has a significant influence on the pulsating wind.Based on the basic theory of fluid mechanics,the analysis reveals the formation mechanism of the wind load characteristics of the roof.(3)Pneumatic measures research: Through the study of the flow characteristics of the roof,two basic aerodynamic wind-resistant measures are proposed to add a baffle and a venting hole at the leading edge of the cantilevered roof;and further to these two types of pneumatic measures The parameter analysis and optimization combination are given to give a more reasonable construction method of pneumatic measures.The research results can provide a useful reference for practical engineering applications.