Limit Value of T-Shape Prestressed Concrete Bridge for Traffic Safety

Based on the theory of energy random analysis for train derailment, the safety of running trains on five bridges of which lateral vibration amplitudes surpass limit values given by existing code is analyzed. The calculated results manifest that the existing limits value of bridge lateral vibration amplitude for traffic safety are too conservative. A new method for establishing the limit value of bridge lateral vibration amplitude for traffic safety is proposed on the basis of the analysis theory for train derailment. The detailed steps of the method included presentation of condition for derailment prevention determination of the critical system of beam and pier for derailment prevention, and calculations of limit value of bridge lateral vibration amplitude of the system of beam and pier for traffic safety. With the method, the limit values of lateral vibration amplitude for traffic safety of 32 m and 24 m long T-shape prestressed concrete bridge are determined as L/3980 and L/4411 respectively. Finally, L/4500 is determined as the recommended limit value of lateral amplitude of T-shape prestressed concrete bridge for traffic safety.