What aspect does not contribute to increased concrete compressive strength?

Adding excessive water does not contribute to increased concrete compressive strength; in fact, it can have the opposite effect. The strength of concrete is highly influenced by the water-to-cement ratio, which determines the hydration process and, ultimately, the durability and strength of the finished product. When too much water is added to the mix, it facilitates the formation of voids or air pockets within the concrete as it cures, leading to a reduction in density and strength.

Proper mixing techniques ensure that the components of the concrete are well-distributed and combined, which can enhance overall strength. Utilizing high-quality aggregates contributes to compressive strength because stronger, well-graded aggregates provide better interlock and support within the mix. Incorporating pozzolanic materials, such as fly ash or silica fume, can improve the strength of concrete by reacting with the calcium hydroxide produced during hydration, enhancing the overall properties of the concrete over time.