Some Elements of Operational Modal Analysis

Table 1

Modal identification on dataset 1 of the Heritage Court Tower case.

Modal quantity	Modal identification method
	AR	ITD	ERA	SSI	FDD	FD-PR
Mode 1, 𝑓𝑛, (Hz)	1.227	1.227	1.227	1.227	1.225	1.228
Mode 1, 𝜍𝑛, (%)	0.96	0.97	0.96	0.53	1.29	1.32
Mode 1, 𝜋𝑛, (%)	30.1	30.2	30.1	32.6	27.9	29.7
Mode 2, 𝑓𝑛, (Hz)	1.285	1.285	1.285	1.284	1.287	1.290
Mode 2, 𝜍𝑛, (%)	1.19	1.20	1.19	0.58	1.41	1.46
Mode 2, 𝜋𝑛, (%)	19.2	19.3	19.3	18.5	17.4	19.0
Mode 3, 𝑓𝑛, (Hz)	1.452	1.451	1.452	1.450	1.450	1.454
Mode 3, 𝜍𝑛, (%)	1.11	1.11	1.11	0.63	1.59	1.36
Mode 3, 𝜋𝑛, (%)	50.6	50.5	50.6	48.9	55.8	51.3