STUDY ON STATISTICAL DAMAGE MODEL OF TRIAXIAL CREEP OF CONCRETE

In order to investigate the triaxial creep characteristic of concrete, a triaxial compression test and a triaxial creep test of concrete were carried out with a SAM-2000 triaxial electronic-hydraulic serve system controlled by a computer. And the results show that the confining pressure can significantly increase the carrying capacity of concrete. The greater the confining pressure is, the higher the axial carrying capacity of concrete would be, while the creep deformation volume and deformation rate change to be smaller, conversely. Assuming that the damage of concrete is caused by the damage accumulation of its internal micro-elements,and there exists a certain relationship P#x003b5; between the failure probability of micro-elements and the strain of concrete,and the failure obeys the Weibull distribution, the statistical damage variable can be worked out by the triaxial compression test results. Based on the rheological model of Burgers,the statistical damage model of triaxial creep of concrete is established through introducing the damage variable. The model parameters are fitted by MATLAB software, and after a comparative analysis, the fitting results of model curves and test curves come to be more satisfied, and the greater the main deviatoric stress is,the more accurate the fitting results are. This model can be used for a later reference.