Design and Experimental Study of a Harp-Shaped Single Span Cable-Stayed Bridge

Abstract

This paper presents issues in the design concept, analysis, and test results of a harp-shaped single span cable-stayed bridge, Hongshan Bridge, located in Changsha, Hunan Province, China. The bridge has a 206 m span, with a pylon inclined at 58° from the horizontal and 13 pairs of parallel cable stays without a back stay. This paper discusses the design approach for the main components of the bridge. Emphasis will be put on the following three aspects. First, the weight of the pylon and all dead loads of the main girder in addition to part of the live loads must be in a balanced condition. Second, the main girder should be an orthotropic steel-concrete composite box girder because of the superior safety and weight reduction of this type of structure. Third, the cable stays should be anchored at the neutral axis of the pylon to prevent the development of high secondary moments caused by other anchor approaches. Furthermore, based on results from tests carried out on three models, namely, scaled full model tests in a scale of 1:30, scaled section model tests in a scale of 1:6, and wind tunnel tests, the following four key issues were studied: (1) the local stability of orthotropic steel-concrete composite box girder subjected to combined bending and axial loads; (2) the characteristics under loads of 13-m-long cantilever beams; (3) the safety of the bridge under some other dangerous conditions; and (4) the characteristics of wind resistance and wind tunnel testing.