Research On Some Problems And The Design Of Concrete-filled Steel Tubular Arch Bridges

This thesis based on a through bowstring concrete-filled steel tubular(CFST)arch bridge,establishing the 3-d simulation model of arch bridge by using MIDAS Civil,and research on some issues of this arch bridge,the main subjects are summarized as follow:(1)This thesis has described the development of CFST arch bridges,the structure characters,existing problems,design and calculation methods,as well as simulation techniques.(2)This thesis has designed a CFST arch bridge,and checking calculation the strength in ultimate limit states,the anti-crack of normal and oblique section in serviceability limit states,as well as the compressive stress of normal section and principal compressive stress of oblique section in lasting states,the results has showed that all the calculations met the demand.(3)There was the difference of actual structure state and ideal state due to the tolerance of structure design parameters.This thesis has made the parameter sensitivity analysis of arch bridge in order to calculate the influence degree of structure state induced by design parameters.There was a lot of factors can produced the structure states,this thesis through some parameters such as dead weight,elastic modulus,cable forces,environment and temperature to show who was the main design parameters,and who was not which could play a role in tolerance control of structure design and construction.(4)This thesis has analyzed the natural vibration characteristics due to it's the basic of dynamic analysis and anti-seismic,and has got former 10 vibration models and frequency.This thesis has used the minimum strain energy method to calculate the final suspender force,and proposed to modify the final suspender force based on changing boundary condition,this method could be a reference of similar arch bridge for calculating the final suspender force.(5)This thesis has introduced two kinds of stability problems of arch bridge,and has compared the buckling coefficient of arch bridge in existing or not the arch rib brace,the results showed that arch rib brace played a role in enhance the integrity of structure.