| Leaning-type arch bridge is a new type of spatial arch bridge developed in recentyears, which is composed of two main arch ribs and two stable arch ribs. Becausethere are no transverse braces between the main arch ribs, the lateral stability wouldbe a crucial control factor for bridge design, so the lateral buckling of leaning-typearch bridge are studied in this paper. Based on the energy method, the deformationenergy of main arch ribs, stable arch ribs formation model and transverse bracesbetween main and stable ribs, non-directional load potential energy of hangers andexternal loading potential energy are constructed, and a series of original researcheshave been completed as follows.(1)It is derived for the first time that the lateral buckling critical load analyticalsolution of leaning-type arch bridge with the circular arch axis under the hingedboundary condition of main arch ribs and clamped boundary condition of stable archribs. And the analytical solutions of the lateral buckling critical load under differentdeformation energy combinations have been derived also. Furthermore, the influenceparameters of the lateral buckling critical load have been analyzed. It is shown thatthe boundary condition, the inclined angle of stable arch rib, the transverse brace’sbending stiffness, and non-directional load of hangers are the critical effect factors ofthe lateral buckling critical load of the bridge. And the lateral buckling critical loadunder clamped boundary condition is approximately2.98to4.31times as large asthat under hinged boundary conditions.(2) Taking the leaning-type arch ribs with the catenary arch axis as the researchsubject, the lateral buckling critical load analytical solutions of the leaning-type archribs and the leaning-type arch bridge are derived for the first time. The both wascompared and it’s shown that the lateral buckling critical load of leaning-type archbridge is approximately2.4to3.7times as large as that of the leaning-type arch ribs(Namely the increased coefficient of the lateral buckling critical load isapproximately between2.4and3.7.). Then the impact of those design parameters onlateral buckling critical loads are analyzed, such as rise-span ratios, arch axiscoefficient, incline angle of the stable arch, the transverse brace’s stiffness, the number of transverse brace, the top distance of the main arch and the stable arch ribs.(3) The lateral buckling critical load analytical solution of the leaning-type archribs with the parabolic arch axis is firstly derived. Then the lateral buckling criticalload under three different types of arch axis which is circular, parabolic and catenaryare compared, and.it is shown that, the critical load of the leaning type arch ribs withthe parabola arch axis is the biggest, the catenary takes second place, and the circularis the minimum. |
