Characteristics Of Wind Loads And Wind-induced Response Analysis Of Tensile Membrane Structure

Due to the properties of Tensile Membrane structure such as large span,flexibility and low natural frequency of the Tensile Membrane structure,it is very sensitive to wind load and often damaged under strong wind,but there is no specification for wind shape coefficient and wind vibration coefficient for membrane structure design at present.So it is very significant both for theory and practical engineering to understand the wind load characteristic of the surface and to predict the wind-induced response of membrane structure rationally.In this paper,wave type and umbrella-shaped tensile membrane structure were taken as the object of study.On the basis of statistically calculating the membrane structure engineering examples,the rigid model pressure test is designed and completed in view of the commonly engineering parameters.Then the wind load and wind-induced vibration response characteristics are systematically analyzed.The main work includes:First of all,the rigidity model of wave type and umbrella-shaped membrane structure was designed based on summary of project examples.Then the wind tunnel test was carried out under different working conditions.Wind load characteristics,such as the worst wind pressure distribution on the structural surface were got.The influence of wind directions,rise-span ratio,bottom environment(open and closed mode),eave height and different flow fields on the average and fluctuating wind pressure distribution was investigated.The results showed the wind angle,the bottom environment and flow fields greatly affected while the rise-span ratio and eave height effect were small.Finally,the regional wind shape coefficients were proposed for engineering reference.Then the wind-induced response analysis is executed based on the wind tunnel test data with time-history method considering influence of different factor such as wind directions and speed,initial pre-tension,span and rise-span ratio.The results indicated that bottom environment caused a great difference in response,and it can reduce wind-induced reaction effectively if decreasing span or increasing initial pre-tension.The designing methods of Tensile Membrane structure were discussed at last.Mainly for some load analysis regulations in Membrane Structure Design Specification,the wind-induced vibration coefficient for the whole structure and non-linear adjustment coefficient of wave type and umbrella-shaped membrane structure response(node displacement,element internal force,bearing reaction force)were given.Then wind-induced vibration coefficient,limit of membrane surface displacement were probability counted based on the result of wind-induced vibration,the corresponding values upon than 95% guarantee rate were obtained.Then the influence of fold characteristics and area on the mechanical properties was analyzed,and the fold area reference limit was determined.