Research On Performance-based Seismic Capacity Analysis Of Aqueduct

The shortage and illogical distribution of water resource in our country are the most important factors which restrict economy developement of our country currently.Aqueduct as an important water supply structures play an significant role in the rationnal allocation of water resource and sustainable developement.However for a long time,aqueduct seismic design lacks an specialized standard,designers usually carry on an design according to the highway bridge standard.In the aqueduct seimic research,the upper supported water body's inflence can not be neglected.At the present time,the water body in aqueducts implified methods are divided into two kinds. One are the linear method, such as Westergaard additional mass,Housner model. The other are the nonlinear method, which studies on the efect of liquid nonlinear sway to aqueduct, such as boundary element method, ALE finite Element Method etc. Considering the fluid-strcuture-interaction boundary condition,the 2D slot-water-coupled FEM eaquation is derived from the fluid and structure basic dynamic equations,then the genneral equation of additional mass method is aquired furthermore.Base on the performance-based method,an analynical modal of framed bent supported aqueduct with consideration of FSI is build.Then the capacity curve of shearing force of the basement of aqueduct versus the displacement of the roof of structures is obbtained from the push-over analysis.A discution is done about the applicability of the push-over method on aqueduct based on the comparison of the result of nolinear dynamic time-history analysis.Base on the improved capacity spectrum method which is found by Chopra,this pape adopted the Vidic R_μ-μ-T modal,established the inelastic demand spectrumbase on the design spectrum of the hydraulic structure seismic design standard and the procedure for finding the target displacement.Currently,the most-use aqueduct seismic capacity analysis methods is empirical analysis and checking computation based on the standard.Because of the limitation of the two methods in the accurate assessment of the strucure's elastic-plastic seismic capacity,referring to the earthquake loss experience of the bridge,this paper gives the ultimate state of the pier,and build the destroy state measurement standard represented by the ductility factor.The target displacement of the example under different magnitude earthquake is calculated,the the seismic capacity of this aqueduct under according earthquake is given based on the measurement standard.Finally,an summary of this pape is done and an suggestion is given that the capacity spectrum method(CSM) is applicable for the seismic capacity analysis of the aqueduct,some further research problems are discussed also.