Reducing the porosity of castables can effectively improve their density, strength and erosion resistance, and the key lies in the strict control of the following four aspects.
1. Optimize Particle Gradation
Adopt continuous gradation, reasonably match coarse and fine aggregates to achieve tight stacking; fill the gaps with ultra-fine powders such as micro powder and silica fume to reduce porosity from the source.
2. Strictly Control Water Addition
Add as little water as possible on the premise of meeting the construction fluidity, and use high-efficiency water reducers to reduce the water-binder ratio, avoiding the formation of a large number of pores after water evaporation.
3. Standardize Construction Vibration
Stir mechanically evenly and vibrate fully until the surface exudes slurry and no bubbles are discharged, ensuring the material is dense and eliminating internal pores.
4. Scientific Maintenance and Baking
Maintain and solidify according to the system, follow the heating curve during baking, slowly discharge moisture, and prevent micro pores and cracks caused by rapid heating.
Through the multi-dimensional control mentioned above, the porosity of the castable can be effectively reduced, significantly improving its overall performance and usability.
