Structural Damage Detection Based on Modal Parameters Using Continuous Ant Colony Optimization

Table 6

Comparison of damage scenario between the present algorithm and [9].

Damage case	Element	Actual damage	Detected damage
			As per Yu and Xu [9]			Proposed algorithm			Improvement in accuracy (%)
Percentage of noise included*			0	5	10	0	5	10	0	5	10
F1	17	0.5	0.42	0.42	0.40	0.5	0.5	0.4	16.0	16.0	0.0
F2	8	20	18.8	17.5	16.5	20.0	20.8	19.6	6.0	8.5	15.5
	17	20	18.5	17.2	16	20.0	20.0	14.7	7.5	14.0	−6.5
F3	8	10	11.8	10.8	14.5	10.0	10.2	16.8	18.0	6.0	−23.0
	11	20	17.2	18.5	14.3	20.0	20.0	20.9	14.0	7.5	24.0
	17	3	4.7	3.5	5.5	3.0	3.6	1.2	56.7	−3.3	23.3
F4^1	5	15	13.2	14.5	14.7	14.9	13.4	14.4	11.3	−7.3	−2.0
	8	15	12.1	12.6	13.2	12.0	11.1	10.4	−0.7	−10.0	−18.7
	11	20	18.2	17.9	15.5	19.8	19.3	18.0	8.0	7.0	12.5
	17	3	4.1	4.4	4.7	2.7	2.7	0.0	26.7	36.7	−43.3
F4^2	5	15	13.2	14.5	14.7	15.0	15.5	13.8	12.0	0.2	−6.1
	8	15	12.1	12.6	13.2	15.0	14.3	15.0	19.3	11.1	11.9
	11	20	18.2	17.9	15.5	20.0	20.3	18.6	9.0	9.1	15.5
	17	3	4.1	4.4	4.7	3.0	1.6	1.9	36.7	1.0	19.0

Values indicate the added noise level in mode shapes. The noise level in natural frequency is taken as one tenth of that of mode shapes.
¹Maximum number of iterations considered as 1000.
²Maximum number of iterations considered as 2000.