Pore Structure and Influence of Recycled Aggregate Concrete on Drying Shrinkage

Table 3

Effect of different pores on the properties of hardened cement paste.

Name	Diameter	Description	Role of water	Impact on performance
Capillary pores	10–0.05 μm	Large capillary pores (macropores)	Performance such as volume water	Permeability, diffusion
	50–10 nm	Medium capillary pores (large capillary pores)	Generating small surface tension	Permeability when no macropores exist, shrinkage when relative humidity is greater than 80%
	10–2.5 nm	Small, independent capillary pores (small capillary pores)	Generating large surface tension	Shrinkage when relative humidity is between 50% and 80%
Gel pores	2.5–0.5 nm	Micropores	Strong water absorption, no planum semilunatum	Shrinkage and performance in all relative humidity ranges
	≤0.5 nm	Mezzanine space