Algebraic Method On Creep And Shrinkage In Steel-Concrete Composite Beam

With the development of time, shrinkage and creep of concrete will lead to redistribution of internal force for the steel-concrete composite structure, which have an influence to the safety and serviceability. This thesis with the steel-concrete composite beam as the research object, it analyzes the effect of shrinkage and creep of concrete. Derivation of equation in force method is the research method. Simply supported composite beam and continuous composite beam are the focus of research. According to the content of paper, it may be divided into the following areas:(1) Stating from the mechanism of shrinkage and creep, it summarizes the influence factors of shrinkage and creep, than make the above mechanism and influence factors corresponding to the model of related specification. In addition, because of the particularity of high-strength concrete, it through comparing and analyzing list prediction accuracy to high-strength concrete of the all kind of creep model and explain the improvement of the new model of CEB-FIP.(2) Stating from the principle of linear superposition, it derive the integral constitutive relation, differential constitutive relation and algebra constitutive relation. This paper adopts the Algebra constitutive relation and therein narrates the aging coefficient.(3) based on Trost’s algebraic equation as stress-strain constitutive relation, it derived usual internally and externally statically indeterminate problem in engineering.(4) It is through theoretical derivation and combining with the example that the problem of shrinkage and creep in composite beam is researched. For the Simply supported composite beam, it summarized mechanical effect due to the shrinkage and creep of concrete slab and influence factors of this effect. For the continuous composite beam, it summarized effect of shrinkage and creep in the case of considering the construction process and support settlement.