Damage Analysis Of Huilan Overpass Bridge Based On OpenSees

The curved bridge with small curvature reradius is widely applied in overpass and highway overpass constructions.In Wenchuan earthquake,Huilan overpass bridges with small curvature reradius is a typical example,which has aroused numerous attentions for its serious damage.Based on the engineering background of collapse and the damage of the Huilan overpass bridges,and by using OpenSees analysis along with taking non-linearity time interval analysis procedure,research on the bridge seismic response and earthquake hazard,the paper was written.In order to accurately mimic the column shear failure response,the simulation of 12 groups of reinforced concrete column with shear failure of pseudo static tests and the 4 groups of reinforced concrete column vibration tests were completed.Based on which,the OpenSees analysis considering pier shear effect way of modelingwas established.The main jobs and processes are as followed:(1)Introduce expound history and actuality of earthquake damage of curved bridge and seismic study.Introduce the research status of numerical analysis model of bending shear failure piers in the OpenSees analysis platform.(2)The numerical analysis model of concrete column referring to destroy of bending shear failure was established,based on Opensees analysis,along with Elwood Model and Leborgne Model.According to the numerical analysis of static tests of 12 groups of bending shear failure of reinforced concreted column,results were led to by Elwood model,tending having a lager deviation,which could probably be resulted by the great dispersion of parameters estimation formula.Once the parameters were identified by the test results,more accurate simulation of hysteretic performance could be acchieved by Elwood model.A better result was led to by Leborgne model,as it can stimulate the hysteretic curve of the column.(3)By numerical simulation of 2 groups of the bending shear failure of column,and 2 groups of vibration failure of column,Leborgne model is proposed by numerical pseudo-static test preparation and identification of hysteretic performance parameters of the column.By completing the column by Elwood model nonlinear time history analysis,to achieve the analysis of bending shear failure process of the column time.The results of shaking table tests of the column with shear failure verified the possibilities of the ideas and hypothesis mentioned above.(4)Based on the OpenSees,with the consideration slip of bending shear failureand bearing separation,the analysis model to the nonlinear seismic response of overpass bridge D ramp bridge wad established.T-hrough a combination of input 5 earthquake waves,including Wenchuan earthquake waves,discusses its characteristics and seismic response.The study found that under different earthquake waves of the short pier No.2(fixed)almost all yield and into the plastic,when the pier shear failure,the shortest pier No.2(fixed)reach shear failure point with the development of bridge pier top displacement ductility,the bearing capacity decreases,bending shear failure features appear simultaneously.During the analysis,bridge bearing mostly occurred sliding response,consistent with the damage phenomenon,the vertical seismic wave make a greater impacton on the abutment and the junction of pier bearing,while only the wave of El Centro earthquake appears a hollow phenomenon at the junction of pier bearing.