Research On The Lateral Stability Of Standard Concrete-Filled Steel Tubular Arch Bridges With Single Pipe Ribs

This paper take CFST arch bridge with single pipe ribs as research object, the lateral stability of CFST arch bridge with this kind of section was studied here, maily investigated the construction of the standard bridge that consider the lateral stability, calculation method of the elastic lateral stability capacity and ultimate bearing capacity of CFST arch bridge with single pipe ribs. The main work and conclusion of this paper are listed as fellows:(1) Construct three span range standard CFST arch bridge based on the existed CFST arch bridge statistical data and related documents and related standards. And the safety of the arch rib was checked here.(2) Because the existing calculation methods of the elastic lateral stability capacity of arch bridge were based on the small shear deformation assumption the result of these methods was a magnitude less than the result of FEM method, and makes these methods unfit for the calculation of elastic lateral stability capacity of CFST arch bridge with single pipe ribs.(3) Turn problem of lateral stability of arch bridge into the problem of the stability of batten plate column, and propose the formula of elastic ultimate bearing capacity Pcr of CFST arch bridge with single pipe ribs by solving the flexural differential equation of axial compression column that consider the large shearing deformation then infer the formula of lateral slenderness ratio. Meanwhile, because the crossbars of CFST arch bridge with single pipe ribs wasn’t arranged at equal intervals use du and d132 to take the place of d/2 when calculate the shear deformation and propose the expression of shear coefficient μ of the single pipe rib-steel pipe crossbar system. The contrast to the result of FEM method show that the formula for the elastic lateral stability capacity that consider the large shear deformation puted up in this paper can get the right result of the elastic lateral stability capacity of CFST arch bridge with single pipe ribs that use the sparse crossbar arrangement.(4) The parameter analysis of CFST arch bridge with single pipe ribs indicate that the lateral slenderness ratio has a strong influence on the ratio Ke/KP of elastic characteristic value Ke and the ultimate bearing capacity coefficient Kp. Get the fitting formula of the ratio Ke/Kp of elastic characteristic value Ke and the ultimate bearing capacity coefficient Kp by taking this main parameter and put up the practical calculation method of Kp. Take three span range standard CFST arch bridge as example to contresr the FEM result of Kp to the formula result of Kp, and the result show that the differrnce between the formula result and the FEM result is less than 10%.