When considering concrete, what property decreases when too much water is added?

When too much water is added to concrete, the compressive strength decreases. The compressive strength of concrete is primarily influenced by the water-to-cement ratio; adding excess water dilutes the mixture and creates a lower density concrete.

Water molecules occupy spaces between the other components, which can lead to the formation of voids as the concrete cures. These voids not only weaken the overall structure by reducing density but also decrease the bond strength between the aggregates and cement paste. As a result, the concrete becomes more prone to cracking and has reduced load-bearing capacity, which is why its compressive strength diminishes with excess water.

While workability may initially appear to improve with added water, it can lead to an unstable and weaker end product, undermining the quality and performance of the concrete over time. The initial setting time and durability are also negatively affected, but it is the compressive strength that stands out as the most directly impacted property when excess water is incorporated into the mix.