Finite Element Analysis Of Three-arched Aqueduct Based On FSI System

In order to change the current situation of uneven distribution of water resources,many water delivery projects have been built in China.Aqueducts are an important type of water transmission structure.The destruction of aqueducts may lead to the breakage of the entire water supply line.Therefore,the structural safety analysis of the aqueduct is extremely important.This paper takes the Wangwang Aqueduct as an example,carries out finite element analysis of the aqueduct structure,and evaluates the safety of the aqueduct structure.An integral model of triple-arched aqueducts was established.The overall modeling of aqueducts can simulate real working conditions compared to single-arch analysis,thus making the results more accurate and reliable.In the static analysis,the concrete four-parameter damage model was introduced to find the location where the concrete was easily damaged,and compared with the results of internal force analysis to verify the applicability of the concrete four-parameter damage model.The analysis results show that the locations where the concrete is prone to damage are in accordance with the locations where the internal forces are relatively large.Therefore,the four-parameter damage model can be used for the static calculation of the aqueduct.The safety evaluation of the aqueduct structure is based on this,and the results meet the specification requirements.When the aqueduct is in the over-water state,the interaction between the tank body and the water body has a great influence on the structural dynamic response analysis and cannot be ignored.The fluid-structure interaction should be simulated to obtain the actual response results.At present,scholars at home and abroad study the effect of simulated water mainly using Westergaard additive mass method and Housner spring model,only considering the effect of water body on the unilateral aspect of the tank wall.In this paper,the displacement-pressure(u_i,p)format based on the FSI system is introduced.The three-dimensional acoustic unit is used to simulate the water body.It can simulate the absorption and reflection of water on the solid boundary.The natural vibration characteristics of the aqueduct were studied in three working conditions.The analysis result shows that the effect of water can reduce the natural frequency of the aqueduct and make the distribution of vibration modes more concentrated.Due to the lack of measured data,the seismic design code for hydraulic engineering has not described the aqueduct.Researchers and designers often perform seismic analysis on the aqueduct according to the bridge design specifications.In this paper,response spectrum analysis of aqueduct is carried out according to the new seismic design code for hydraulic engineering.Based on the results of the response spectrum analysis,the El-Centro seismic wave is input to study the time-history response of the aqueduct structure.The analysis result shows that the aqueduct is the most unfavorable condition when the tank depth is reached,and the internal force meets the requirements of structural safety design.The response law of the time-history analysis with response to the depth of water is similar to that obtained by the response spectrum method.which explain that the two can verify each other.