The Study Based On Damage Theory About The Durability Of Concrete Under Freeze-Thaw Cycles

The anti-frost property of concrete is one of the major parts of study on the durability of concrete. By viewing all over the world, due to the alternation of external temperature upon and under zero centigrade, concrete structures located on the areas of high latitude are usually unavoidable to suffer the damage caused by freeze-thaw cycles. Due to the insufficiency of theoretical foundation and the complexity of freeze-thaw durability itself, the contemporary studies are far from integrity in respect to the theoretical consensus. What is more, the researching measures concentrate more on the experimental approach. Based on this, it would be necessary to carry out relevant theoretical study on the freeze-thaw durability of concrete.This paper, by rooting upon the damage theory, tries to carry out quantified study on the damage of concrete caused by freeze-thaw cycles. Under such premise, this paper attempts to shed light on the damage characteristics macroscopically by setting the research foundation upon the interior microcosmic damage being brought by freeze-thaw cycles. By referring to some of the existing theoretical damage models, the two phase model of accumulated damage under freeze-thaw cycles is put forward. In the mean time, because the characteristics of concrete can influence its anti-frost properties, this paper puts forward two coefficients, known asλandγ, to represent the anti-frost capability of concrete. What is more, by putting emphasis on studying the connections between concrete characteristics and these two coefficients, this paper carried out statistical analysis on existing research data, the evaluation of the above mentioned coefficients is given. Finally, by carrying out relevant experimental study, this paper compared the experimental data with the data retrieved from the said theoretical model. The result shows the theoretical model adapts well with the actual circumstances.