Which of the following is an essential factor in achieving high durability in concrete structures?

Achieving high durability in concrete structures fundamentally relies on controlling the water-cement ratio. The water-cement ratio significantly influences the strength and permeability of the concrete. A lower water-cement ratio typically leads to a denser concrete matrix, which reduces the number of voids and increases the binding of the materials. This density is vital because it limits the ingress of harmful substances—like chlorides and sulfates—that can lead to deterioration over time.

In contrast, using too much water in the mix can lead to a weak and porous concrete structure, making it more susceptible to damage from freeze-thaw cycles, chemical attack, and wear. Therefore, maintaining an optimal water-cement ratio is essential for enhancing the longevity and durability of concrete structures. Ensuring that the right amount of water is used contributes to a strong, impermeable structure capable of withstanding various environmental stresses and conditions.