In order to study the mechanical performance of a new type of cable-stayed beam-arch combination bridge, the results of field static and dynamic load tests are comparatively analyzed with numerical results based on th...In order to study the mechanical performance of a new type of cable-stayed beam-arch combination bridge, the results of field static and dynamic load tests are comparatively analyzed with numerical results based on the Jingyi bridge straddling the Daxi River in Yixing. First, the test scheme, tasks, the corresponding measure method, as well as the relevant codes are described. Secondly, two sets of three- dimensional finite element models are established. One is Ansys which uses the solid element and the other is Midas which adopts the beam element. Finally, the experimental and analytical results are comparatively analyzed, and they show an agreement with each other. The results show that the bridge possesses adequate load-carrying capacity under all static load cases, but the capacity of dissipating external input energy is insufficient due to the relatively smaller damping ratio. The study results can provide a reference for further study and optimization of this type of bridge. Calibrated finite-element models that reflect the real conditions can be used as a baseline for future maintenance of the bridge.展开更多
Concrete footbridges, due to their mass, stiffness and damping, are perceived as strucaires more resistant to vibration caused by dynamic action of the users. In order to verify the dynamic behaviour of concrete footb...Concrete footbridges, due to their mass, stiffness and damping, are perceived as strucaires more resistant to vibration caused by dynamic action of the users. In order to verify the dynamic behaviour of concrete footbridges, a series of field tests and numerical analyses have been carried out. In the paper, the results of the dynamic field tests of three medium span concrete footbridges with different structural systems （frame, beam and arch footbridges） and their dynamic characteristics （mass, stiffness and damping） are presented. The field tests were carried out for different types of vibration excitation caused by walking, running and jumping persons. Furthermore, the vibrational comfort criteria for footbridges are shortly described and verified for examined structures. The study were supplemented by numerical calculation of natural mode shapes and frequencies of the structures using the 3D FEA （finite element analysis） models with elastic supports elements in order to ensure the compatibility of the calculated and measured mode shapes of the footbridges.展开更多
文摘In order to study the mechanical performance of a new type of cable-stayed beam-arch combination bridge, the results of field static and dynamic load tests are comparatively analyzed with numerical results based on the Jingyi bridge straddling the Daxi River in Yixing. First, the test scheme, tasks, the corresponding measure method, as well as the relevant codes are described. Secondly, two sets of three- dimensional finite element models are established. One is Ansys which uses the solid element and the other is Midas which adopts the beam element. Finally, the experimental and analytical results are comparatively analyzed, and they show an agreement with each other. The results show that the bridge possesses adequate load-carrying capacity under all static load cases, but the capacity of dissipating external input energy is insufficient due to the relatively smaller damping ratio. The study results can provide a reference for further study and optimization of this type of bridge. Calibrated finite-element models that reflect the real conditions can be used as a baseline for future maintenance of the bridge.
文摘Concrete footbridges, due to their mass, stiffness and damping, are perceived as strucaires more resistant to vibration caused by dynamic action of the users. In order to verify the dynamic behaviour of concrete footbridges, a series of field tests and numerical analyses have been carried out. In the paper, the results of the dynamic field tests of three medium span concrete footbridges with different structural systems （frame, beam and arch footbridges） and their dynamic characteristics （mass, stiffness and damping） are presented. The field tests were carried out for different types of vibration excitation caused by walking, running and jumping persons. Furthermore, the vibrational comfort criteria for footbridges are shortly described and verified for examined structures. The study were supplemented by numerical calculation of natural mode shapes and frequencies of the structures using the 3D FEA （finite element analysis） models with elastic supports elements in order to ensure the compatibility of the calculated and measured mode shapes of the footbridges.
