Research on Extending Span of Box Girder Bridge with Corrugated Steel Webs up to 300m

摘要

In order to promote the application of steel-concrete composite structure in mountainous areas in China, a conceptual design for a PC continuous rigid frame box-girder bridge with corrugated steel webs and main span of 300 m was performed in the present paper. The combined corrugated steel web was proposed to increase the compressive area and improve the stability performance; thus, the self-weight of the composite box-girder bridge is significantly reduced. Flexural capacity of the whole section had been calculated with a single-beam model for the ultimate limit state (ULS). For the service limit state (SLS) design, the calculation for the composite box-girder bridge was conducted with the spatial grid model (SGM), from which 27 complete checking stresses in three layers (i.e. outside, inside and middle planes) of concrete plates and steel webs in every cross-section could be obtained. The stress history under construction stage was incorporated into the results obtained by SGM. Moreover, the stress states and stability performance for the composite box-girder bridge constructed were evaluated. The present investigation can provide references for the design and construction of the composite box-girder bridge with corrugated steel webs for long spans.