Analysis And Calculation Of Construction Process And Completion State For Long Span Reinforced Concrete Arch Bridge

The reinforced concrete arch bridge with stiff skeleton has the merits both of the CFST arch bridge and the concrete arch bridge. Especially, the self-spanning system during the construction brings much convenience. It brings a good choice for building long span arch bridge and provides a good development direction.The finite element simulation analysis of traditional construction process is usually used to beam element to simulate bridge construction phases, get the internal force of completion state by using birth and death of element method to simulate the construction process through accumulating the force. The arch of Beipanjiang bridge using a longitudinal section. transverse ring gradually pouring to form composite section, its construction features:structure system transformation frequency, structure stiffness and strength is gradually formed by combination of every process. In the simulation of construction process of arch ring section, it is not a one-time completion of construction. It is difficult to use the traditional beam element for simulating arch ring of segmental construction method in the internal force analysis. Construction method for simulation analysis should gradually activate cross section, by using the stress accumulation method to get the structure internal force. For the same section of arch box, side box before middle box completed and a longer time interval, this will lead to bigger time differenc for different parts of the same cross-section. How to reflect creep process during the construction needs for a specialized study.The simulation analysis of bridge structure construction process adopts the method simulating bridge structure by the beam element, activating or inactivating of the bridge unit, superpositing internal forces to obtain the final completion operation force approach. There are few reports about construction simulation analysis taking box cross section formed gradually. Taking the Beipanjiang Bridge as the engineering background, the thesis establishes the bridge construction process and operation stage static simulation model, analyzes deformation and internal force of the Beipanjiang bridge construction process and operation stage. Based on the calculation results, it gives the evaluation about the structure bearing capacity limit state (such as bearing capacity and stability of the main arch ring) and normal service limit state (the structure deformation and the stress level) of the construction process as well as the completion state.