Study on the Effect of Curing Temperature on Tensile Creep of High Performance Concrete at Early Ages
|School||Zhejiang University of Technology|
|Course||Bridge and Tunnel|
|Keywords||High performance concrete Tensile creep Curing temperature Loading age Equivalent Age Early Age|
High - performance concrete volume changes caused by the stress analysis of one of the prerequisites for cracking predicted tensile and creep properties of early age concrete grasp early age tensile creep apparatus and measurement methods , and how to establish accurate determination and the evaluation and prediction of creep characteristics of critical research. In this paper, the early design of the study group , the improvement of the tensile creep device , a more systematic evaluation of the influence of the curing temperature and loading the age of tensile and creep properties of high performance concrete at early age , and by the concept of equivalent age rheological principle to establish the mathematical model , the analysis of the experimental data of tensile creep early age tensile creep prediction equations and their validation. The main conclusions of this study are: (1) improved tensile creep experimental device and method can be more efficient determination of the early concrete stretching under different temperature and loading the age of creep characteristics . ( 2) the mechanical properties of high-performance concrete , first 3d rapid development , after slowing down , and the higher the temperature , the more rapid development and changes of the mechanical properties . (3) of concrete of the same age tensile elastic modulus (Et) and the compression modulus of elasticity (Ec) and showed a good linear relationship between the concrete under different temperatures , that Et = 1.084Ec . (4 ) under the same curing temperature , the age of the concrete loading later , creep smaller the value , the slower the rate of creep . And with the holding of the charge time of growth , the the concrete creep rate under different loading age difference is getting smaller and smaller . (5) the same load under the age of the concrete tensile creep size will decrease as the temperature increases , and loaded earlier age , this is more obvious decline . ( 6 ) the use of equivalent age to consider different curing temperatures for the concrete tensile creep suitable ZC model is established based on this creep prediction equations to describe the the loaded concrete before the 3d natural age creep development characteristics.