Time-history Analysis Of The Nonlinear Wind Response Of The Multi-span Continuous Bridge

Abstract:China is attacked by about10times of typhoons each year, which leads to frequent and severe storms that threaten the lives and property of the masses. Long-span bridges, which are particularly important for some insurmountable terrain, are so-called lifeline projects. Therefore, the significance to do research on the resistance of long-span bridges to wind is obvious.Currently, frequency-domain analysis methods are used extensively to obtain the wind response of the bridges. But when encountering geometry, material or contact nonlinear problems that are inevitable in practical engineering, we can only get approximate results that are quite different from the analytical solutions. Then, it’s time to think about the method of Time-history Analysis which can provide an acceptable accuracy for that kind of problems.In this paper, stochastic simulation methods have been studied in view of shortcomings found in frequency-domain analysis method. The time history of the six-dimensional fluctuating wind speed with spatial correlation has been simulated by FORTRAN programs, which is a necessary step for the time-history analysis of the nonlinear wind response of multi-span continuous bridges. Then some common numerical integration methods have been summarized, and their advantages and disadvantages have been pointed out. At last,the time history of wind-induced buffeting response has been calculated under the condition of muti-support excitation, with the Newmark-β method and wind load,which is calculated by simulated time history of fluctuating wind speed and average wind data of practical engineering. The calculation demonstrated great differences when compared with the results of frequency-domain analysis method,which provided references and conclusions for the design and management of the abilities of multi-span continuous bridges to resist storms. The paper contains45...