Study On The Deformation And Stress Performance Of A Special-shaped Concrete-filled Steel Tube Arch Bridge With Curved Steel Box Beam

LTG Bridge as a landscape bridge in a tourist scenic area, is a special-shaped concrete-filled cteel tube arch bridge with crved steel box beam, the span of which is (2×30+80+2×30) m, and the width of which is29.5meters. The application of similar bridge at home and abroad is little. Because the main arch and the center line of the bridge in the horizontal projection is misaligned, the deformation and stress distribution of the bridge are very complex. In this paper, the deformation capacity and mechanical performance of the ZTH Bridge both under construction state and completion state was analyzed, the main work and achievements are as follows:1. The finite element simulation method of the special-shaped concrete-filled steel tube arch bridge with curved steel box beam was studied. The space grillage method was adopted to simulate the curved steel box beam, and the concrete-filled steel tube arch was simulated by stiff superposition method. The established FEA model of the whole bridge were applied for the finite element analysis of the bridge under dead load、worst-case load、temperature load.2. The paper analyzes the deformation capacity and mechanical performance of the LTG Bridge both under construction state and completion state. The calculation results reveal that the bridge has good bearing capability during construction and service stage. But it is worth noting that the transverse horizontal displacements of the main arch under all kinds of load are greater than the vertical displacements.3. The mechanics characteristics of the bridge under wind loads, temperature loads and non uniform settlements of supports were researched. Based on the above, one can draw some conclusions as follow:Temperature loads have great effect on the deformation and loading of the steel box girder. The deformation of the under temperature loads is approached to that under worst-case of live load. Wind loads have great effect on the deformation and loading of the main arch. The transverse horizontal displacements of the main arch is half of that under dead load.The steel box girder and the arch have been less affected by non uniform settlements of supports.4. The position of the main arch in the transverse bridge was studied, and put forward the proposal to move the designed location of the main arch1m outward, so as to improve deformation and stress state of the main arch. The proposal has been applied in the final design.The results of this article provide design basis for LTG Bridge, and are of reference value to other similar bridges. This paper has168graphs,4tables and61references.