Influence of Alternation of Sulfate Attack and Freeze-Thaw on Microstructure of Concrete

Table 1

Chemical and physical properties of cement, fly ash, and slag.

	Chemical composition/%										Physical properties	Compressive strength of cement/MPa
	SiO2	Al2O3	Fe2O3	CaO	MgO	K2O	Na2O	R2O	SO3	loss	Specific density; /(kg/m^3)	7 days	28 days
Cement	22.53	3.89	4.88	63.00	2.09	0.50	0.09	0.42	2.08	0.59	3120	25.4	45.1
Fly ash	52.44	24.03	9.44	3.20	1.14	—	—	—	0.73	2.24	2380	—	—
Slag	33.67	14.60	1.72	34.67	9.89	0.65	0.27	—	1.95	2.38	2860	—	—