Calculation Method Of Lateral Buckling Critical Load Of Leaning-type Arch Bridge

Leaning-type arch bridge,a new type of arch bridge has been developed in recent years. Ithas a special stylish profile and good economic perfermence,providing an open view fordrivers,so it is competive in the urban areas. Its rib system is composed of two pieces of verticalmain arch ribs and two pieces of stable arch ribs on the sides of main ribs. Its lateral stability isthe control factor in bridge design because there is no transverse brace between the main archribs. Taking the leaning-type arch bridge as the subject,a series of researches were completed.Firstly, taking circular arch as the subject, its deformation energy and potential energy ofexternal forces were constructed based on assumed displacement function of lateral buckling ofthe circular arch in this paper. Based on Ritz method, the analytical solution of lateral bucklingcritical load of the circular arch was derived. Compared with the results obtained from FEM andpredecessors' formula, it is verified that the analytical solution presented in this paper is accuratesufficiently.Secondly, taking leaning-type arch rib system as the subject, lateral and radial deformationmodels of the transverse brace between the main arch rib and stable arch rib were proposed inthis paper. The analytical solution of lateral buckling critical load of leaning-type arch rib systemwas derived for the first time. By compareing the results obtained from FEM, it is verified thatthe analytical solution presented in this paper is accurate sufficiently. Then, the influence ofthose design parameters such as the deformation energy of the stable rib and transverse bracebetween main rib and stable rib and inclining angle and rise-span ratio and length of thetransverse brace was analyzed.Finally, considering the non-direction forces of suspenders and the floor system, the elasticdeformation energy of the main ribs and stable arch ribs and transverse brace, and potentialenergy of non-directional loads and external forces were constructed.Based on Ritz method,thecalculation method of lateral buckling critical load of leaning-type arch bridge was proposed forthe first time.The influence of later bending and torsional stiffness of stable arch rib and incliningangle, radial and trangential bending stiffness of transverse brace and non-direction forces ofsuspenders and the floor system on the lateral buckling critical load were studied.