Concrete polishing uses densifiers to achieve a better shine. Polishing works by smoothing out peaks and valleys in the surface; if the concrete is not strong enough, this abrasion will remove micro-chunks that decrease the surface uniformity and quality of shine. Concrete surfaces face two major obstacles to polishing: bleed water and pores.
Excess water in newly placed concrete rises to the surface. This bleed water carries with it the finest aggregate and laitance, making it much softer than the slab’s core. It also increases the water to cement ratio, which further weakens the surface. Densifiers address this problem by binding to available lime in a pozzolanic fashion, creating additional cementitious material and strengthening the surface.
Concrete is by nature a porous material, with pores formed by water evaporation during curing. These pores interfere with surface uniformity, and make the slab more susceptible to staining from spilled liquids. The additional cementitious material formed by the densifier and lime fills these pores.
Densifiers may use various carrying agents to accomplish the hardening process, potassium, sodium, lithium, or other agents.
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