The Seismic Performance Experimental Research And Theoretical Analysis Of Roundended Hollow Piers In High Speed Railway

At present, there is very few research on the seismic behavior of the hollow piers of domestic high speed railway.Due to lacking related data, it’s badly in need of mass special research on the seismic behavior of hollow piers.For providing the theory basis to perfect the relevant high speed railway bridge seismic design code, this paper makes experiment study and theoretical analysis on the high speed railway roundended shape hollow piers.It mainly research four factors such as axial compression ratio, shear span ratio, longitudinal reinforcement rate and the stirrup ratio influence on the seismic performance of roundended shape hollow piers. Specific content as follows:(1)Through making low cyclic loading test to seven high speed railway roundended hollow pier model having different design parameters, it analyzes destructional forms and stress of pier models, obtains load-displacement hysteresis curve of the pier, comprehensively analyzes the ductility performance, energy dissipation capacity and stiffness and strength degradation, and obtain the relationship between seismic performance index and shear span ratio, the axial compression ratio, longitudinal reinforcement rate and stirrup ratio.(2)Using finite element analysis software ABAQUS, combined with the test results, it comparely analysis the seismic performance of roundended hollow pier of the high speed railway.From the intensity and rigidity characteristics, ductility, energy dissipation of hollow pier assesses the test results, and in-depth analysis factors such as axial compression ratio, shear span ratio, longitudinal reinforcement rate and the stirrup ratio influence on the seismic performance and ductility failure mechanism.Aiming to different shear span ratio and axial compression ratio under the condition of the hollow pier longitudinal reinforcement and stirrup configuration parameters analysis, and raise the suitable reinforcement suggested value for high-speed railway roundended hollow piers.(3)Based on the theoretical analysis and test data regression analysis, it analyzes the model hysteresis curve and skeleton curve parameters of roundended hollow pier, and discusses the the constitutive relation of concrete with less constraints reinforced, simplifies its skeleton curve as stiffness degradation three line model, determines the hysteresis standards, build simplified restoring force model of roundended hollow pier, lay the foundation for high speed railway bridge seismic response analysis of elastic-plastic theoretical.