Concrete Mix Design for Service Life of RC Structures under Carbonation Using Genetic Algorithm

Table 7

Comparison with results from test and simulation from GA.

w/c (%)	Diffusion coefficient (10^−11 m^2/sec)	w/c (%)	R.H. (%)	Cement (kg/m^3)	S/a (%)	Coarse aggregate (kg/m^3)
42	1574	42.0	10	425	44.4	895
Input range	—	40–45	10-10	400–450	39–45	800–895
Result from GA	1580.5	41.5	—	419.2	41.8	874.5
Relative error (%)	0.4	−1.2		−1.4	−5.9	−2.3
42	1257	42.0	45	425	44.4	895
Input range	—	40–45	45-45	400–450	39–45	800–895
Result from GA	1194.2	42.1	—	420.8	42.2	869.7
Relative error (%)	−5.0	0.24		0.0	−5.0	−2.9
42	1105	42.0	75	425	44.4	895
Input range	—	40–45	75-75	400–450	39–45	800–895
Result from GA	1088.4	42.2	—	421.2	42.0	882.1
Relative error (%)	−1.5	0.5		−0.9	−5.4	−1.4
42	862	42.0	90	425	44.4	895
Input range	—	40–45	90-90	400–450	39–45	800–895
Result from GA	855.2	41.8	—	426.1	43.2	887.2
Relative error (%)	−0.8	−0.5		0.3	−2.7	−0.9
50	2520	50.0	10	315	41.0	1076
Input range	—	47.5–52.5	10-10	290–330	39–45	950–1100
Result from GA	2775.2	49.8	—	311.8	42.6	1085.3
Relative error (%)	10.1	−0.4		−1.0	3.9	0.9
50	1950	50.0	45	315	41.0	1076
Input range	—	47.5–52.5	45-45	290–330	39–45	950–1100
Result from GA	2124.2	51.3	—	318.5	41.2	1092.5
Relative error (%)	8.9	2.6		1.1	0.5	1.5
50	1503	50.0	75	315	41.0	1076
Input range	—	47.5–52.5	75-75	290–330	39–45	950–1100
Result from GA	1452.2	49.3	—	322.2	41.8	1044.7
Relative error (%)	−3.4	−1.4		2.3	2.0	−2.9
50	1105	50.0	90	315	41.0	1076
Input range	—	47.5–52.5	90-90	290–330	39–45	950–1100
Result from GA	1127.3	48.2	—	318.9	39.5	1068.5
Relative error (%)	4.0	−3.6		1.2	−3.7	−0.7
58	4480	58.0	10	277	39.4	1117
Input range	—	55–60	10-10	260–330	39–45	950–1300
Result from GA	4922.3	57.2	—	266.2	39.7	1204.2
Relative error (%)	9.7	−1.4		−3.9	0.8	7.8
58	2350	58.0	45	277	39.4	1117
Input range	—	55–60	45-45	260–330	39–45	950–1300
Result from GA	2472.3	58.9	—	270.5	40.1	1200.8
Relative error (%)	5.2	1.6		−2.4	1.8	7.5
58	1450	58.0	75	277	39.4	1117
Input range	—	55–60	75-75	260–330	39–45	950–1300
Result from GA	1377.2	57.8	—	277.7	42.2	1208.7
Relative error (%)	−5.0	−0.3		0.3	7.1	8.2
58	1172	58.0	90	277	39.4	1117
Input range	—	55–60	90-90	260–330	39–45	950–1300
Result from GA	1150.2	59.4	—	278.5	41.9	1187.5
Relative error (%)	−0.9	2.4		0.5	6.4	6.3

The bold numbers are results from GA.