Comparison of analytical methods for the abutment-backfill interaction of a rigid frame bridge with high piers under seismic loading
Xu Lueqin , Qiao Wanzhi , He Luping , Xiang Zhongfu , Liu Jincheng
DOI:10.11835/j.issn.1674-4764.2016.06.014
Received May 10, 2016,Revised , Accepted , Available online July 04, 2017
Volume ,2016,Pages 105-112
- Abstract
Four analytical models are proposed for examining the effect of gravity abutment-backfill interaction based on current seismic design codes from home and abroad. The mechanical constitutive relationships as well as computing formulas are presented. Nonlinear time history method is applied to comparatively study the effect of abutment-backfill interaction on a rigid frame continuous bridge with double thin-walled piers, which is currently under construction. The results showed that only the spring model can obtain the closest higher-order elastic modes to those of the refined model. In the longitudinal direction, the results from the roller model and the bearing model are both much smaller than that of the refined model. The error of the spring model, compared with the refined model, is the smallest with the critical internal force errors not exceeding 20%. In the transverse direction, the bearing model is the closest to the refined model in calculating the internal forces, and both the spring model and the roller model predict conservative results with respect to that of the refined model. The influences of the abutment stiffness and effective participating mass on the critical seismic internal forces are smaller than 10% and 15%, respectively. Hence by comprehensively taking the prediction accuracy and computational cost into consideration, the spring model is the most suitable choice in seismic design of bridges.