The Research Of Theoretical Analysis And Experiment On Expansion Reinforcing Strip

Along with the widely application of the super-long RC structures, expansion reinforcing strip has been applied to achieve seamless in the super-long RC structures. The scarcity of details in current standard about expansion reinforcing strip leads to the design and construction mostly depend on empirical methods. But there are many problems needed to be solved at present. The research was carried out on this background, the method of combining theory and experiment was used to study the expansion reinforcing strip.Firstly, the capability of expansion concrete was introduced with the basic calculation parameter and the collocation of expansion reinforcing strip, based on the compensate shrinkage principium of expansion concrete. The sort of expansion reinforcing strip and the influence to the shrinkage of concrete in the structure were also discussed.Secondly, one flat super-long RC frame structure with expansion reinforcing strip was simulated by the finite element software ANSYS. The shrinkage and expansion of concrete was treated as temperature, and the gravity of concrete was taken into account. Then the stress and deformation of the super-long concrete structure were analyzed, and the influence of the expansion reinforcing strip on the structure was also presented.Thirdly, the experiment was conducted in order to verify whether the confined expansion ratio could satisfy the engineering requirement or not. The experimental result agreed with the theoretical value. And the confined expansion ratio of expansion concrete in different restriction was also contrasted and analyzed.Fourthly, experiment of strain monitoring was carried out. The concrete strain of the expansion reinforcing strip and some beam and plate were contrasted and analyzed, the strain distributing trait along longitudinal and lateral orientation were contrasted with the results of simulation with finite element method. The tension stress of concrete was verified not exceed the tensile strength. Then the experimental data were analyzed using time sequence forecast analysis method, and later concrete strain was forecasted, the security of the structure was also verified.Finally, the suggestion calculation method of super-long concrete structure was put forward based on the theory of concrete shrinkage. The segmental shrinkage deformation and strain of concrete were analyzed with the simplified method. The test value of the expansion reinforcing strip agreed with the theoretical value. Then, theoretical value and test date were analyzed using unitary linearity regression analysis method, so as to educe suggestion calculation formula which is meaningful for the practical engineering.