Research on the Overall Design and Key Technology of Long-Span Suspended Monorail Steel Box Composite Beam.

The suspended monorail is a new mode of rail transit with light weight, medium speed and low cost. It has a lightweight and aesthetically pleasing structure but has obvious limitations when spanning obstacles such as rivers and valleys. From the perspective of structural force and operational safety, this paper puts forward a new composite beam structure scheme, in which track piers and track beams are erected on the main beam of a cable-stayed bridge, overcoming the limitations of conventional suspended monorail spanning ability. To investigate the complex force situation and the load transfer path at the junction of the main beam of the cable-stayed bridge and the track beam piers, finite element models of steel box girder section and concrete box girder section were established using ANSYS software. The results showed that, in the steel box girder section, the pier load was mainly transferred to the diaphragm and the middle web directly connected to it. Among them, the diaphragm load experienced relatively uniform stress, while the middle web's stress was mainly concentrated within a 2-meter radius centered around the pier, which could be mostly transferred to the steel girder bottom plate. 58% of the pier's axial force was transferred to the directly connected diaphragm. During the transfer of the pier column's transverse bending moment, 58. 8% of the shear force was transferred to the directly connected diaphragm. During the transfer of the pier column's longitudinal bending moment, 53. 4% of the shear force was transferred to the middle web. In the concrete box girder section, the pier load was mainly transferred to the concrete web and diaphragm directly connected to it. The concrete stress was mainly concentrated within a 2-meter radius centered around the joint surface, and the pier load was basically transferred within about 0. 5 meters below the joint surface. 68. 8% of the pier's axial force was transferred to the directly connected diaphragm. During the transfer of the pier column's transverse bending moment, 86. 4% of shear force was transferred to the directly connected diaphragm. During the transfer of pier column's longitudinal bending moment, 44. 6% of shear force was transferred to the middle web. [ABSTRACT FROM AUTHOR]