Wind Response Analysis Of A Long-span Steel Truss Arch Bridge

In the last decade, with the core technology of China’s high-speed Railway becoming mature, a large number of high-speed railways and passenger dedicated lines are built in the country which high-speed railway traffic mileage has been significantly increased. Due to long-span steel truss arch bridge’s great stiffness and strong spanning capacity, it has been widely used in high-speed railway. While in the effect of wind load, buffeting is easy to happen in the long-span steel truss arch bridge, which will affect the vehicle ride performance, reduce fatigue life of the structure and bring passenger discomfort at the operational phase, too large static and buffeting response will also affect the construction safety during the construction phase. Based on a long-span railway steel truss arch bridge, this paper gives a detailed analysis on static and buffeting response when the bridge is at the time of final stage and building stage. The main contents and results of the paper include the following aspects:1. It has introduced the development of arch bridge and main contents and methods of wind-resistance research, and reviewed the research status quo of bridge buffeting response.2. It has given a detailed introduction about the characteristics of natural wind and the basic theory of bridge wind-resisitance analysis, whose focus is on the analysis method of buffeting.3. According to the spatial distribution of long-span steel truss arch bridge, the three-dimensional fluctuating wind field has been simplified into a plurality of linear one-dimensional wind field, then the simulation of the wind field has been realized by using Constant Amplitude Wave Superposition. It proved that the method is effective and properly by examining the simulated wind velocity series.4. It has introduced the basic theory of dynamic characteristics analysis and the method of transient dynamic analysis, then established the finite element model of the bridge by using the finite element software ANSYS. In this paper, a single equivalent beam model has been established by using the equivalent stiffness method. It proved that the method is feasible by comparing the results of the dynamic characteristics of the two models.5. Under the design basis wind speed, a detailed analysis on static and buffeting response has been given when the construction is in the final stage and using stage. The time domain analysis method has been used in the analysis of buffeting response. While it also has analyzed the relationship between wind-induced displacement response and the wind speed.