| The large-span CFST arch bridge is developing rapidly in recent years due to its elegant appearance and economical span. Raw support cable hoisting method is adopted for the construction of most CFST arch bridges, which is developed into jack cable inclined pulling and buckling method later. Precise calculation of proper buckling force is needed in the multi-segment hoisting method to make sure that the structural stress and geometry under bridge complete stage can meet the requirements. Based on comprehensive collection of existing research documents in and beyond the country, the characters of cable hoisting method is analyzed and the calculation method for proper bucking force used frequently at present is generalized and compared in this paper. The Raw support cable hoisting method for the construction of empty steel tube is studied and calculation method for proper bucking force based on optimization theory is put forward. Aim at optimization on single-objects and multi-restriction of construction control of CFST arch bridge, aggregate function is used to aggregate multi-restriction. Problems of single-objects and multi-restriction are transferred to optimization problems of single-objects and single-restriction. Lagrange Multiply Method is used to transfer the question of single-objects and single-restriction to that of none extremum, then the answer is gotten. Based on pre-strain and Methods of Influence Matrix, this paper contributes design of cable strength to pre-strain. Multi points and internal force are selected as control objects. In finished state, these control objects are similar to that of expected. Optimization function of single-objects and multi-restriction has been found to adjust errs of CFST arch bridge before the construction of empty steel tube be folded. Method of optimization are adopted. Through the model experiment of The Maocao Bridge in Nan county, this method is validated.
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