Experimental Study On Shrinkage And Early Creep Of Limestone Mechanical Sand Concrete

With the reduction of natural sand resource, the application of mechanism sandreceives more and more attention; However, It is rare to research on the shrinkage andcreep tests of mechanism sand concrete in domestic, so it is necessary to research on theshrinkage and creep of this kind of concrete. Specific work is as follows:The mechanisms as well as the influential factors are researched,which lay afoundation for selecting reasonable prediction models.The test on the creep and shrinkage as well as other material property and mixproportion experiments of mechanism sand concrete are carried out on the background ofthe project“Limestone mechanism sand concrete and the long-term behavior of Beipanjiang super-large bridge”, according to measurement data, fitting out shrinkage and creeprelational expression, which was compared by several existing prediction models of creepand shrinkage: ACI-209、CEB-FIP、GL2000and B3models. The test results show thatreinforcement ratio has a certain degree of influence on the concrete shrinkage strain andcreep coefficient.Based on the shrinkage and creep tests of mechanism sand and common sandconcrete standard specimen, the different concrete age of loading on creep coefficientwas discussed, the difference of creep coefficient between mechanism sand and commonsand concrete was compared; According to the measured data, fitting out shrinkage andcreep relational expression, then modify the creep coefficient expression, so as to get thereasonable creep coefficient expression that suitable for the concrete beam, which wascompared with the creep deflection coefficient. The result of the comparsion indicatesthat creep strain coefficient is larger than creep deflection coefficient.The concrete shrinkage and creep are simulated by the means of ANSYS andMIDAS/Civil, and its results are compared with the measured data.