Damage Characteristics of Sandstone Subjected to Coupled Effect of Freezing-Thawing Cycles and Acid Environment

Table 3

Average dry mass of sandstone before and after suffering different pH and F-T cycles.

pH	Situation description	Average mass of dry samples (g)
		10 cycles	20 cycles	30 cycles	40 cycles
2.8	Before F-T	385.10	394.46	392.20	394.00
	After F-T	381.44	387.4	380.29	355.04
	Discrepancy	−3.66	−7.06	−11.92	−38.96
4.2	Before F-T	387.20	391.89	394.31	390.62
	After F-T	384.87	385.62	383.23	375.59
	Discrepancy	−2.34	−6.28	−11.08	−25.04
5.6	Before F-T	386.52	388.07	395.07	391.77
	After F-T	384.32	383.35	380.37	370.82
	Discrepancy	−2.2	−4.73	−9.06	−20.9
7.0	Before F-T	386.7	390.66	387.19	392.90
	After F-T	385.12	387.6	381.28	373.2
	Discrepancy	−1.58	−3.06	−5.9	−19.7