Durability of microsilica concrete, subjected to arabian gulf exposure

الملخص EN

Premature deterioration of reinforced concrete structures is a serious problem in the Arabian Gulf.

Much of this deterioration is caused by chloride ingress through the concrete, which results in the corrosion of the reinforcing steel.

Over the last 5 years, the practice of specifying microsilica in concrete has widened, as engineers work to improve the durability of concrete, which is subjected to the severe exposure conditions in the region.

Current practice is to use microsilica additions ranging from 5% to 10% depending on the degree of exposure.

Are these amounts of microsilica sufficient to maintain a realistic life span for concrete structures? How much microsilica is really needed to provide durable concrete with an appropriate life under the varying exposure conditions? In this paper, models are proposed to estimate the chloride ion ingress into Portland cement concrete and microsilica enriched concrete under different exposure conditions.

The results show that small amounts of microsilica are sufficient as long as appropriate concrete covers to reinforcement are maintained and chloride exposure to the concrete is correctly assessed.