RESEARCH ON 2-DIMENSION,3-DIMENSION CARBONATIONS AND SUPERPOSITION COEFFICIENT OF FLYASH CONCRETE

Through a study on 2-D and 3-D carbonations of high_performance concrete with different flyash proportion(0%,15%,20%,40%,60%), the test methods of 2-D and 3-D carbonations are built; the mathematical models of 2-D and 3-D carbonations are also proposed. The superposition coefficient of 2-D and 3-D carbonations are defined; the mathematic formula of the superposition coefficient is given. The experiment indicates that the carbonations of 2-D and 3-D are similar to that of 1-D, which obey the exponential function of time t. At the same time,they have superposition coefficient obviously. During the early stage carbonation, the superposition coefficient of 2-D can be over 4.0, and it can be 6.0 of 3-D. During the carbonation of 28 days (which corresponds to natural carbonation of 50 years), the superpostion coefficient of 2-D can be over 2.0, and it can be 4.0 of 3-D. The superposition coefficient obeys the attenuation function through time t.