Analysis Of Safety Of Long Span Continuous Beam Bridge During Cantilever Casting Stage

Cantilever method is generally used in the construction of large-span continuous beam bridge. With the increase of the span, wind effects on the bridge become more and more significant. The vibration response of bridge under the state of longest cantilever during construction is induced by wind load, and will affect the construction and safety of structure will be influenced by excessive response. So wind load can often become the dominant load, and it should be fully considered in the bridge construction. While the loads caused by extreme construction, such as Casting error and hanging basket falling off, should also be controlled. The responses of large-span continuous beam bridge under wind load and construction load are calculated of this thesis. The Huaihe River Bridge, the main span of which is 100m, in the Fuyang to Liuan railway is taken as example. The following main research results are drawn:1. The development of wind resistance study, the basic theory and calculation method of wind resistance is introduced in continuous beam bridge.2. According to the results of numerical simulation theory and using the Midas calculation software, the aerostatic stability, wind load response and the flutter stability of Huaihe River Bridge under the maximum cantilever state are checked in this thesis.3. the extreme loads in continuous beam bridge construction is studied in this thesis, and the structure's internal force, strength and deflection is calculated under the combination situations of construction error, hanging basket error and hanging basket falling off.4. According to the construction monitoring data, the control section stress is analyzed during the construction. The differences that the actual stress state of the bridge has been shown in this thesis. The results that the maximum cantilever stage, closure stage and completed bridge stage are the most unfavorable construction stages and construction risk maybe greater due to various uncertainties are shown by calculation analysis. So these stages should be the focus of construction control.