Research On The Influence Of Transverse Joint Reinforcement On The Seismic Dynamic Nonlinear Response Of Arch Dams

A number of concrete arch dams currently being constructed in southwestern China,such as Jinping I,Xiaowan,Baihetan,Hutiaoxia,Dagangshan,etc.Due to the complex environmental conditions in this area,they are also in high-intensity strong earthquake areas.Arch dams are prone to damage to the dam body under strong earthquakes,affecting their normal operation.In severe cases,they may even threaten the safety of life and property of the downstream people.Therefore,it is very important to study the seismic reinforcement of arch dams under strong earthquakes.According to the engineering data of the hyperbolic arch dam,a three-dimensional numerical model of the arch dam is established in the finite element software,and based on this model,the contact module in the finite element software is used to set the contact unit of the transverse joint of the arch dam to calculate the seismic load of the arch dam.The response results are analyzed,and the stress distribution,relative displacement value,damage size and development process of the key parts of the dam body,as well as the distribution law and maximum opening value of the joint opening are analyzed.(1)According to the actual engineering data,a three-dimensional numerical model of the arch dam is established in the finite element software,and on the basis of this model,the contact element in the finite element software is used to simulate the transverse joint of the arch dam,and the response result of the arch dam under the seismic load is calculated.The distribution of stress in key parts of the dam body,relative displacement of the dam body,damage size and development process as well as the distribution law and maximum opening value of transverse joint opening are analyzed.(2)For the study of anti-seismic measures of arch dams,the arch ribs are used to enhance the seismic performance of the dam body.Because the design and arrangement of arch reinforcements are more complicated,consider changing the length of the reinforcement between the transverse joints,Reinforcement rate two influencing factors,using the rod element module in the finite element software to simulate steel bars,using a separate steel barimplantation method,inserting in the part of the dam body stress and strain affected by the seismic response and the larger opening Reinforcement arrangement,and analyze and deal with the nonlinear response results of arch dam reinforcement.(3)By comparing and analyzing the seismic response results of dam body stress,dam crest displacement,transverse joint opening,etc.with and without reinforcement,as well as different layout schemes.By comparing the stress of the dam body under the seismic load,the displacement of the crest,and the opening of the transverse joint,the results show that After the reinforcement is inserted into the joint,the stress value from the arch direction of the dam body increases,and the opening of the transverse joint of the arch dam body decreases.The comparison results show that the reinforcement measures between the transverse joints of the arch dam can control the dam body in strong earthquakes.The stress changes generated under the alternating load can also reduce the maximum opening of the transverse joints and prevent the damage of the transverse joints between the dams due to excessive opening.The feasibility of the reinforcement of the transverse joint between the dams to improve the seismic performance of the arch dam was verified.