Experimental Study on the Durability of Fly Ash-Based Filling Paste in Environments with Different Concentrations of Sulfates

Table 5

Uniaxial compressive strength of filling paste after immersion in different concentrations of sulfate solution.

Sulfate concentration		Uniaxial compressive strength (MPa)
		30 d soaking time			60 d soaking time			90 d soaking time			120 d soaking time
Clean water	Test results	10.27	9.98	10.08	12.51	12.67	13.1	13.92	13.51	13.76	14.37	14.66	14.53
	Mean value		10.11			12.76			13.73			14.52
	Standard deviation		0.14			0.31			0.21			0.15
5%	Test results	10.32	10.61	10.81	13.42	13.56	13.82	15.92	15.51	15.73	15.95	16.32	16.11
	Mean value		10.58			13.60			15.72			16.13
	Standard deviation		0.25			0.29			0.21			0.19
10%	Test results	10.97	11.55	11.5	15.31	15.97	15.37	14.52	14.91	15.24	12.96	13.89	14.04
	Mean value		11.34			15.55			14.89			13.63
	Standard deviation		0.32			0.36			0.36			0.34
15%	Test results	10.57	10.88	11.07	13.31	13.67	13.64	12.92	12.51	12.31	12.16	11.62	11.41
	Mean value		10.84			13.54			12.58			11.73
	Standard deviation		0.25			0.20			0.31			0.39