Research on Calculation of Impact Coefficient of Long-span Continuous Beam Bridge Based on Quasi Horizontal Orthogonal Test Method
Long-span continuous beam bridges are widely used in highway construction in Chi-na because of their elegant lines and strong adaptability.With the increase of highway traffic load,coupled vibration of axles has become a problem to be reckoned with in recent years.This study focuses on the change law of bridge impact coefficient under the action of heavy-duty vehi-cles,based on the coupling vibration theory of axles.The influences of six parameters were con-sidered,including bridge deck unevenness,driving speed,vehicle load,bridge damping ratio,ve-hicle suspension stiffness and vehicle suspension damping.Altogether 25 test conditions were de-signed with the orthogonal test method,and the calculation formula of impact coefficient of long-span continuous beam bridge was obtained step by step.The results show that the parameters that significantly influence the impact coefficient of deflection are:bridge deck unevenness,vehi-cle suspension stiffness,and vehicle load;bridge deck unevenness has the greatest influence on the parameters of bending moment impact coefficient.The correlation coefficients of deflection impact coefficient and bending moment impact coefficient are 0.896 and 0.856,respectively,and the regression model fits well.The test results provide a reference for the revision of the impact coefficient of long-span continuous beam bridges in relevant specifications.
long-span continuous beam bridgeintended level orthogonal test methodimpact coefficientregression equation