Measures to Improve the Durability of Concrete

Incorporating High-Efficiency Water-Reducing Agents.

While ensuring the required workability of the concrete mixture, it is important to minimize water usage and reduce the water-cement ratio, thereby significantly lowering the total porosity of the concrete, especially the capillary pore ratio. When cement is mixed with water, a flocculent structure is formed. In these flocculent structures, a significant amount of mixing water is trapped, which reduces the workability of the fresh concrete. During construction, to maintain the necessary workability of the concrete mixture, it is essential to increase the amount of water used during mixing, which can lead to the formation of excess porosity in the cement paste structure.

By adding a water-reducing agent, the cement particles become oriented, and the surfaces carry the same electric charge. Under the influence of electrostatic repulsion, this not only keeps the cement system in a relatively stable suspended state but also forms a layer of solvated water on the surface of the cement particles, releasing the free water trapped within the flocculated structures of the cement. This achieves the goal of water reduction. Many studies have shown that when the water-cement ratio is reduced to below 0.38, the goal of eliminating capillary pores can be achieved. The incorporation of high-efficiency water-reducing agents can effectively reduce the water-cement ratio to below 0.38.