| In the recent years, material of concrete filled steel tubular has been used widely with the development of transportation enterprise. Shrinkage and creep of concrete filled steel tubular is got more attention.In the thesis, process of creep cognition is narrated in detail, and produce mechanism, characteristics and influence factors of shrinkage and creep are elaborated. Then basic theory of shrinkage and creep analysis and calculative methods are summarized. The domestic and international stipulations for creep coefficient are compared and analyzed.Through leading into the concept of creep free strain increment and actual strain increment and creep flexible strain increment, and creep free strain increment formulas under core concrete stress unceasing change are derived. According to the balanced condition that the sum of force increment is '0' on section of concrete and the steel tubular, the expression of strain increment and curvature increment and creep self-stress and creep second-inner-force and creep second-stress are reached. According to above-mentioned theory, By using Fortran PowerStation 4.0, and combining with finite member step by step method, has programmed CFSTCREEP.EXE correspondingly. Structure deflection and inner force are analyzed by using the program for concrete shrinkage and creep. Results of examples show that the program is correct and feasible.According to condition of deformation coordinate, and using middle value theorem and age theory. The formulas of the last stress increment are got because of concrete creep. The formulas are verified by comparing calculated results with those that are calculated by the program, which will give engineers some conveniences.At last, the program is used to analyze concrete shrinkage and creep of concrete filled steel tubular cantilever beam and steel-concrete composed simple supporting beam and concrete filled steel tubular no-joint arch etc, some valuable conclusions are drawn.
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