Study On Anti-overturning Analysis And Reinforcement Method Of Single Column Pier In Jin-jing Interchange

The single column pier bridges are commonly used in the flyover,interchange and via ductin municipal roads.Instability accidents caused by this type of bridges in construction or daily use have occurred several times,include girder cracking,pier cracking,pier column fracture during the construction,main girder deflection and support collapse,or even the whole bridge overturning.This type of bridge often eccentric risk of overload.Firstly,this paper analyzes the stress characteristics,overturning causes and anti-overturning stability of this kind of bridge.In accordance with the technical features of the single column pier bridges,several strengthening schemes are put forward.Then,four kinds of vehicle loads are proposed in combination with the use status of the Jinjing bridge.Load 1: 1.0 times lane road-grade I load,according to the actual lane position arrangement.Load 2: 1.0 times lane road-grade I load,according to the driveway location eccentric layout.Load 3: 1.2 times lane road-grade I load,according to the driveway location eccentric layout.Load 4: 1.3 times lane road-grade I load,according to the driveway location eccentric layout.Four working conditions are designed in combination with bridge use and environmental factors.This paper use Midas to model the part of its single column pier in these four working conditions.The analysis and calculation results show that under the working condition ?,?,the bridge has risk of support collapse,or overturning.At last,according to the calculation results,the reinforcement method for Jinjing bridge is proposed.Through the calculation and analysis of the reinforcement,it is obtained that adding cover beam is the best reinforcement method.This method is used in Tianjin Waihuan Road reconstruction project.It has significant reference to the reinforcement of this kind of bridges.