Study on the Dynamic Response and Damage Characteristics of Extra-high Arch Dams Under the Effect of Strong Earthquakes
Most of the super-high arch dams in China are built in the southwest region,which is in an earthquake-prone area with large magnitude and high intensity,so the seismic safety of super-high arch dams has been a key concern.Taking the Dagangshan super-high arch dam project located in a strong seismic zone as the research object,the realistic failure process analys software RFPA3D-Dynamics was used to carry out numerical simulations of the ground shaking response.In this paper,the deformation and stress change law of the dam under the action of ground shaking is studied,and the potential destabilization damage area under the seismic action of Dagangshan arch dam is proposed according to the damage evolution and acoustic emission change law.The results show that the local stress concentra-tion and stress release occur inside the arch dam with seismic wave disturbance.The arch dam can rely on its own structural adjustment under the action of the design seismic wave(peak acceleration 0.557 5 g)to maintain a coordinated deformation,with reasonable stress distribution and no large-scale damage.In the case of 1.5 times the design seismic wave,the sudden change in the downstream displacement of the arch dam can exceed 240 mm,which is far beyond the normal displacement and deformation range of the dam body,and the large-scale damage and cracking of the arch dam occurs at this time,and the main damage and cracking areas are the top of the arch crown beam and the middle and upper areas of the left and right half arches.By studying the dynamic response characteristics of arch dams under seismic loading and analysing the damage evolution law,it can be more intuitive to determine the vulnerable areas of arch dams and grasp the working state of arch dams.
NETL
NSTL
万方数据
维普
