Study on evolving model of concrete failure surface in the freeze-thaw condition


ABSTRACT:

The freeze-thaw failure of concrete in many researches is described by dynamic elastic modulus, which is not applicable to estimating the loss of concrete strength in structural engineering. To avoid the deficiency, the paper attempts to establish an applicable failure surface in principal stress space for concrete to describe concrete strength change under different freeze-thaw cycles. Based on the discussion of meson-state of concrete under freeze-thaw cycles, hypothesis about concrete failure surface under freeze-thaw cycles is brought forward. Then, the damage of concrete and build up evolution equations is presented. Finally, a concrete failure surface model is given to predict concrete strength under different freeze-thaw cycles. Compared with available test data, the validity of new model is proven.

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