Stability Analysis Of Continuous Rigid Frame Bridge With High Pier And Large Span

In the recent years,with the fast development of Science & Technology and transportation enterprise,long span continuous rigid frame bridge with thin-walled high piers is commonly built in China,owning to their advantages on economy and construction.However,the stability problem of the bridge,especially in the stage of cantilever construction is more remarkable.In the text,the structural characteristics and the technical content of High Pier and long span continuous frame bridge are generally introduced,the finite-element method is generally introduced for the stabilization analyse.This text bases on the computer simulation theory,applying the large-scale finite element software,adopting parameters to set up the mold of method,building up the equal box high-pier and the changed box beam entity space calculation model of the true size.By changing the parameter,we can imitate various structural model and load conditions,analysis and explore the high pier and large-span continuous rigid frame bridge,in a variety of factors under the mechanical behavior.Based on the Luohe Bridge,this thesis focuses on the stability of the continuous rigid bridge with high Piers during the construction of cantilever.The main work is summarized as follows:(1) The stability analysis of the main pier.This thesis use the main pier 13 has been completed and the beam is not built as the research object,build up the three-dimensional solid finite element model.In the thesis,the structure load in two different ways and the influence to self stability was compared,further more, analyses the buckling stability to the pier with the wind-load effect,which can refer to constructing stability analysis and the calculation as this type.(2) The stability analysis of the largest cantilever construction.This thesis considered two possible load situations aiming at the load(construction load,construction weight error,wind load and abnormal working of hanging basket).The buckling stability analysis of the largest cantilever construction is processed.Through the analysis we find that:the continuous rigid frame bridge in the stability analysis of construction phase and operation phase can meet the calculation precision,and the modeling can be simple as well. Furthermore,this thesis also gets the coefficient of reference loads.The results can make correct evaluation to the stability of the largest cantilever construction and can also provide reference to the practice engineering.(3) The stability analysis of the extended largest cantilever construction.By analysing the most disadvantaged load situation of the stability analysis of the extended largest cantilever,we discuss the limited length of the cantilever and we can know that:the construction phase of the cantilever length on the stability of the piers have great impact:the longer cantilever structure get the smaller stability factor,the actual project's stability analysis can be carried out only on the largest cantilever construction situation.