Thin Walled High-pier Construction Phase Response Analysis Of Wind Loads

With the development of transport,in our country high pier and large-span bridge construction is carry out rapidly,because of the increasing in height of bridge piers,wind resistance of the construction process pier security has became seriously problem.In this paper,based on the research of key technologies for the engineering background of provincial highway S318 line Sanmenxia Westzhangcun bridge variable cross-section of rectangular bridge pierconstruction,according to the large-span pier bridge construction characteristics,wind load artificial time-history simulation,and high pier wind-induced vibration response analysis basic theory,calculation of ideas and content.There is some specific contents of the following:1.To study the thin-walled hollow high pier construction phase wind-induced vibration response,increase the high-pier safety of the construction phase,firstly the article discusses wind load distribution of the high-pier contruction,effect principle,it can provide the theoretical basis of the wind resistance for the further analysis.2.Using the numerical analysis sofeware MATLAB6.5 for the platform,time series using linear filter method of anto-regressive madel(AR madel),carries out nemerical simulation of artificial time-history of the thin-walled high pier construction phase fluctuating wind load,writes the fluctuating wind load time-history simulation program,and determines the optimal auto-regressive model order for the 4 order.3.With the large scale finite element software ANSYS9.0,the artical analyses the dynamics characteristics of the structure in the thin-walled high pier construction phase. obtains the 1～6 order high-pier vibration frequencies and mode shapes;and the same time,the paper studies the wind-induced response of the thin-walled high pier construction phase at the downwind.There are two ways on the wind-induced dynamic response analysis,one is the frequency domain method,the other is the time domain method,the paper compares the calculating results of the two methods,and points out the advantages and disadvantages of the two methods of the high-pier downwind wind-induced response.4.Studing the crosswind vortex-induced resonance in response of the thin-walled high pier construction phase,the paper obtains critical wind speed at the high pier crosswind vibration of the first order and second order,determines the reynolds number range of the first and second order vibration mode,and identifies high pier crosswind resonance height range is 34.6～83m,calculates the structure response of the high pier using multi-particle under the crosswind,compares the results of two methods,at last,points out the reasons of the results small of the calculation of horizontal wind direction in response.5.Analyses the results of the high pier by calculating the construction phase on the effect of wind-induced response,provides technical support for the high pier construction safety.