Freezing-Thawing Damage Mechanism of Coal Gangue Concrete Based on Low-Field Nuclear Magnetic Resonance, Scanning Electron Microscopy, and N₂ Adsorption

Table 1

Basic properties of P∙O42.5R ordinary Portland cement.

Setting time	Flexural strength (MPa)		Compressive strength (MPa)		Fine-grain (%)	Loss on ignition (LOI) (%)	MgO content (%)	SO3 content (%)
	3 days	28 days	3 days	28 days
Initial setting time: 65 min; Final setting time: 5 h	4.3	7.9	24.0	43.5	3.4	2.7	2.2	2.4