Operation Performance Verification of Continuous Box Beam in High Speed Railway

Research purposes: The verification technology of operation performance of continuous box beam with common span is sorted out, in order to provide technical guidance for better operation performance verification of continuous box beam with common span of high - speed railway. Based on the data of the dynamic performance test of high - speed railway bridges in China in recent years and the relevant theoretical research, the measured samples of bridge dynamic performance are statistically analyzed, and the recommended ordinary values of the operation performance evaluation parameters of prestressed concrete continuous box beams at the operating speeds of 250 km/h and 350 km/h are given. Research conclusions: (1) The tasks of operation performance verification of three types of continuous box beam with common span of high - speed railway are defined, and 10 main technical parameters for operation performance evaluation of continuous box beam are put forward. (2)The vertical natural frequency is determined by the power function of span, the vertical damping ratio is 0.5% to 2.0% , the ratio of deflection to span is 1/5 500 to 1/3 500 and 1/6 000 to 1/4 000 respectively, the vertical rotation angle at beam end is 0. 60%crad and 0. 50%crad respectively, the dynamic factor is 1.17 to 1.26 and 1.20 to 1. 30 respectively, the vertical and lateral amplitude at midspan of beam is 0.25 to 0.80 mm and 0. 10 to 0.15 mm respectively, the vertical vibration acceleration at midspan of beam is 0.25 to 0.40 m/s , the lateral amplitude at pier top is chosen as the ratio of the height of pier and the lateral average width of the pier in the range of 0.5 to 4.2, the relative lateral displacement of rail support on both sides of adjacent beam end of ballastless track is 0.5 mm. (3) The research results are in line with the actual state of high - speed railway bridges, which can provide support for the revision of bridge operating performance verification specifications. © 2023 Editorial Department of Journal of Railway Engineering Society. All rights reserved.