The Analysis Of Ateral Rigidity Stability For Pier Ramp Bridge Of Small Radius

With the rapid development of national economy,the advancement of urbanization,more and more highways,urban overhead roads are built and put into use.Ramp bridges are essential as the basic unit of the road to realize each other up and down.Majority of ramp bridges are curve and the longitudinal slope is usually very large,and among them,the single column pier ramp bridges are widely used in urban viaduct and highways because they have advantages such as the shape is beautiful,taking up less space,the vision is fully and the quantities are less.However,single column pier ramp bridge capsized collapse accident news appear frequently in recent years,and investigating its reason,I think that on the one hand,because of curved bridge uniquely "crankle coupling" effect,the bridge cross section in the bending moment and torque is always accompanied by each other,and under the weight of the bridge will produce torque,leading to internal and external beam uneven and the outside counteracting force are larger than the inside counteracting force.On the other hand,the single column pier ramp bridge use single bearing which is unable to withstand the torque,thus the torque of the beam end will be wery large.At the same time,if the auto load is partial even it is overload,the bridge will be easy to collapse and poses a great threat to life and property security,therefore therefore the analysis for the bridge resistive overturning stability is very meaningful.The main content of this paper include:1.Derived the basic differential equation of curve bridge,and introduces several kinds of commonly used analysis and calculation method for curved bridge.At the same time,this paper introduces mechanical characteristics of single pier ramp bridge which.radius is small.2.This paper introduces the basic analysis method of single pier column curve ramp bridge for its resistive overturning stability,which inncludes the Selection of overturning axis,the calculation of stability against overturning coefficient and how to use support reaction for the judge of its resistive overturning stability.And then,this paper tries to use this method into an example.By this example,the paper conclusions the criteria of lateral resistance stability.3.On the base of single column pier ramp bridge in Er Guang highway,changing the radius of curvature,the bridge deck width,the distance between double bearing beam and the eccentric value.And then respectively setting up their finite element.Throughing the bearing reaction force and stability against overturning coefficient method discussed the lateral resistance of single column pier ramp bridge stability with these parameters.