| Landscape bridge with unique shape, complex structure, a good visual effect, is applied to the development of urban bridge progressively. Along with rapid economic development, designers propose many structure of novel forms of landscape bridge, so the research of landscape bridge are urgency. However the research about decorative bridge are extremely rare, especially decorative cable-stayed bridge, which restricts its wide extensive application. So it is necessary to take further research.This paper is to study the structure of decorative cable-stayed bridge by the technical route-“raise questions, create a model, measurement verification, finite element analysis, experimental verification, get structure of force condition and rules”, the main research and achievements of this paper are as follows:1.Full framing construction method of main bridge was proved with theoretical analysis and finite element analysis. Theoretical results agreed better with finite element results, verifying the feasibility of finite element analysis, and then indicate that full framing was secure. Based on the calculation of full framing construction, the results showed that the stress of fourth span to fifth span was greater than other spans in longitudinal direction, meanwhile the shear hold played an important role in the support force; the column bore the most of load during load transmission of support.2.The structure of main bridge was analyzed with finite element analysis and actual measurement results. By measuring the strain and combining with finite element analysis, the results of both were analyzed, meanwhile the stress of main bridge was analyzed. The results showed that the results of actual measured was consistent with the results of finite element analysis, at the same time, the deviation of both results was small, which insured correctness of finite element model. The supported appeared stress concentration, especially hold-down support in longitudinal direction. Because of the existence of shear lag, the stress of webs were bigger than other webs.3.The structure of main tower was analyzed with finite element analysis and actual measurement results. By means of calculation of finite element model and field measurement, the both results was analyzed, and then the stress of main tower during the different construction stages was explained. The results showed that the results of the finite element analysis was consistent with the measured, and the values was within 10% mainly, and then the veracity of the model was verified; Based on the finite element analysis, it came to the conclusion that removing the support of main tower, it led to the stress redistribution, and the floor of main tower being in the compression situation, and the roof main tower being in the tension situation, and extending the force area; The influence of front cable on the main tower was less, and the circle of main tower appeared the phenomenon of tensile and compressive stress in the in the diagonal.4.Based on finite element model of main tower, the dynamic characteristics and air stable performance of main tower were analyzed. By using subspace iteration method, the natural vibration period, natural vibration frequency and mode of vibration of main tower were received. The first order mode shape of main tower appeared out-of–plane bending, meanwhile the rule which changed from in-plane bending to out-of-plane bending was appeared from the first order mode shape to the sixth order mode shape, and the knee points increased. From seventh order mode shape to other model shape behind all appeared out-of-plane bending, and then with analysis of main tower under different design parameters, the boundary condition, structural style of main tower and section form affected the dynamic performance of main tower. On the premise of assumption, nonlinear analysis of main tower, getting the critical load of instability which was 40m/s to 50 m/s, was analyzed. To a certain degree, it showed that the wind-resistant performance was weak. |
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