Seismic Response Analysis Of Integral Abutment Bridges With Skew Angles Considering Soil-Structure Interaction

Jointless bridges can conquer deficiencies of traditional bridges in durability and seismic performance,avoiding diseases of bridge expansion joints,so gradually is spread all over the world in recent years.However,the soil-structure interaction has a greater influence integral bridge,analysis involving complex problems such as soil.The seismic research of jointless bridges is relatively little,especially integral abutment bridges with skew angles,which has affected the popularization of jointless bridges.Therefore,the seismic research of integral abutment bridges with skew angles not only has certain theoretical values,but also has important significance in economics and society.In order to research integral abutment bridges with skew angles considering soil-structure interaction,three-dimensional finite element models of integral abutment bridges with skew angles considering soil-structure dynamic interaction in ABAQUS,which contain foundation soil and the embankment fill,and the simplified models considering soil-structure interaction with p-y curves have been set up and compared,respectively.Furthermore,seismic response of integral abutment bridges with skew angles and factors have been researched.The main works and achievements are listed as follows:(1)The paper introduced numerical method and constitutive model of establishment of whole model,and elaborated simplified calculation methods of p-y curves in lateral soil of piles and the embankment fill.The influence of different scale modeling has been researched.Based on boundary connection principle of multi-scale models,three models were calculated:a beam element model,a solid element model and a multi-scale model,which included static calculation and dynamic calculation.The calculation results of three models were analyzed to prove the availability of multi-scale models.(2)Taking a integral abutment bridge with skew angle as the background,the 3D finite element models of integral abutment bridges with skew angles and corresponding bridges with joints were created,considering soil-structure interaction with p-y curves.Modal analysis and dynamic time-history analysis were utilized in them to compare seismic responses of two bridge types under different earthquake excitations.Dynamic characteristics of two bridge types have been analyzed to prove superiority of jointless bridge in seismic performance.(3)Based on theories of viscous-spring artificial boundary and waves-inputting method,three-dimensional finite element models of integral abutment bridges with skew angles.which contain foundation soil and the embankment fill,and the simplified models considering soil-structure interaction with p-y curves have been set up and compared.Differences of seismic responses in above bridges whose soil was simulated by two methods were discussed to get mutual verification.By comparison of seismic response in frequent earthquake and rare earthquake,influence of nonlinearity of the embankment fill on bridges was analysed to prove limitation of the simplified method.(4)Based on 3D finite element models of integral abutment bridges with skew angles considering soil as solid element,parametric method was adopted to investigate the influence of critical parameters on the deformations and internal forces under different earthquake excitations.In the parametric study,the following factors have been considered:(a)skew angle;(b)backfill stiffness;(c)abutment height;(d)bridge length.The corresponding response regulations are obtained.