Research On Optimization Design Of Track Beam Structure Of Suspended Monorail System

Suspension monorail system is one of the new lightweight form of urban rail transit that is widely used in some developed countries like Germany and Japan, has many advantages such as safe, reliable, fast, green, low engineering cost, short construction period, attrative sightseeing and terrain adaptability etc.Research and the application of suspended monorail system is in its infancy so the relevant technical standards and design specifications are still to be established or improved.As an important component part and technical keypoint of suspended monorail system,the guideway has unnique structure. Designing reasonable and standardized cross section stucture and stiffeners arrangement form of track beam can provide a theoretical reference for domestic introduction and development of suspended monorail in the future.Based on the analysis of the track beam’s structure characteristics,technical parameters and design specifications of foreign operating suspended monorail systems,this paper references Germany small section form as a prototype to achieve an exploratory design on which it has a tentative structure design of the track beam including determining the cross-sectional structure and dimensions, putting forward the checking standard of the stability, strength and rigidity and designing the type of load and loading area of the track beam.By simplifying the structure and decomposing into equivalent load, deformation of the track beam is divided into single-span beam plane bending deformation and partial deformation,and respectively use variable cross-section beam mechanical model and elastic rectangular thin plate model with three edges fixed,one edge free to study with bending deformation with discontinuous stiffener beams and partial reversal deformation of traveling surface of linear track beam between two stiffeners.Based on that this paper tried to research and analysis the effect law on the midspan vertical bending deformation and quantity of steel of linear track beam when it has different span, stiffening rib spacing,width and longitudinal length as well as the thickness of each portion of the slab track beam and the deformation influence of the traveling surface.Meanwhile, the paper focuses on the use of deflection analytic formula to actualize the structural optimization design discussion of suspended monorail linear track beam, which is according to the relevant design constraints to meet the standards and requirements, regard the lightest quantity of steel of 1km linear track beam bridge system as the objective function and the thickness of each part of beam, traveling surface’s width, cross section’s inner height, inner wide and stiffeners’s spacing and longitudinal etc. as the design variables to optimize the structure size of the track beam and stiffener arrangement form. This paper also proposed the track beam structural optimization method and designed the processon, and used Matlab GUI as a development platform to design track beam structure optimization system which can optimize the parameters of rail beam structure more quickly and conveniently by inputting optimization metrics independently, providing a reference for engineering application of suspended monorail transportation.