Advances in Civil Engineering

Research Article

Experimental Study on Mechanical Properties of CFRP-Confined Concrete Columns under Continuous Semi-Submergence of Sulfate

Table 5

Changes in strength and strain of ordinary concrete cylinders under continuous half-immersion in Na₂SO₄ solution.


Specimen number	F (kN)	f_cut’ (MPa)	F_cut’, m (MPa)	ε_cut (×10⁻⁶)	ε_l (×10⁻⁶)	R (%)	R_m (%)

CU0-1	627.61	35.53	35.45	2,810	2,604	100	100
CU0-2	653.18	36.98		2,719	2,707
CU0-3	597.54	33.83		2,692	2,759

CUH60-1	814.17	46.09	44.88	3,045	2,803	130.01	126.6
CUH60-2	771.35	43.67	44.88	3,106	2,789	123.19	126.6

CUH90-1	617.71	34.97	34.73	2,644	2,231	98.65	97.96
CUH90-2	608.98	34.48	34.73	2,498	2,178	97.26	97.96

CUH120-1	568.51	32.19	32.89	2,276	1,904	90.80	92.79
CUH120-2	593.50	33.60	32.89	2,068	1,876	94.79	92.79

CUH180-1	500.35	28.33	28.43	1,788	1,468	79.91	80.18
CUH180-2	503.78	28.52	28.43	1,690	1,404	80.46	80.18

CUH240-1	475.67	26.93	26.52	1,456	1,192	75.97	74.80
CUH240-2	461.08	26.11	26.52	1,487	1,079	73.64	74.80

Note: F is the ultimate bearing capacity, f_cut’ is the compressive strength of specimens, f_cut’, m is the average compressive strength of specimens, ε_cut is the axial strain, ε_l is the lateral strain, R is the strength retention rate, and R_m is the average strength retention rate.