Study on Mechanical Behavior of Reinforced Concrete Beams under Sulfate Attack

Table 5

Degradation of effective cross-sectional area of flexural section.

Corrosion time t (d)	Flexural capacity (kN)	Bending moment (kN·m)	Effective flexural cross-sectional area (mm^2)	Degradation of the effective cross-sectional area i (%)	Degradation rate of the effective cross-sectional area (10^−5)
0	178	59.33	47600.00	0	—
240	175.92	58.64	47240.50	0.76	3.17
360	171.83	57.28	46761.17	1.76	8.33
480	164.84	54.95	45922.35	3.52	14.67
600	154.03	51.34	44604.20	6.29	23.08

Note: degradation rate of effective cross-sectional area = (i₂ − i₁)/(t₂ − t₁).