Influence of freeze-thaw action on carbonation of concrete

many cases, concrete structures are exposed to combined loads such as freeze-thaw cycles and carbonation simultaneously or subsequently. In case there is a synergetic effect between the two environmental loads prediction of service life is not conservative if based on individual actions only. In this contribution, carbonation of four different types of concrete has been studied after exposure to natural atmosphere and for 1 week and 2 weeks accelerated carbonation after 0, 50, and 150 frost cycles. Results show that damage induced by freeze-thaw cycles accelerates the carbonation process. It is also shown that under the combined action of freeze-thaw cycles and carbonation, comparatively more carbonate is being formed in concrete prepared with fly ash. The compressive strength of all four types of concrete decreased considerably under the combined action of the environmental loads. Strength loss was more evident for the concrete with higher water-cement ratio.