Comparison of Field Tests of a PSC Box Girder Bridge with Bridge/Train Interaction Analysis

초록

The estimation of traffic safety and passenger comfort when the train is running on the bridge is unique problem to the railway bridge. The dynamic behavior of a bridge under moving loads has been investigated over many years. Especially, with the introduction of high speed railway, numerous theoretical studies on the interaction problem between bridges and trains are carried out. In the present study, newly developed bridge/train interaction analyses are performed and compared with field tests of a simply-supported 40m long PSC box girder bridge which is typical bridge type of Korean high speed railway. A modified 3-dimensional model of a high speed train which is called KTX is formulated for the interaction of a 3-dimensional bridge model. Equation of motions for the interaction of bridge/train system is also made. Bridge field tests are performed under the passage of KTX train with several speed ranges from about 200km/h to 300km/h. Vertical displacements and vertical accelerations of a bridge with increasing speeds are monitored and compared with the result of analysis. In addition, wheel road reduction rates and acceleration of a car-body of the train are investigated for direct estimation of traffic safety and passenger comforts.