Sensor Placement Strategies for the Seismic Monitoring of Complex Vaulted Structures of the Modern Architectural Heritage

Table 3

Modal properties of the structure and classification of the main vibration modes, considering the damage of the infill walls.

Mode	Frequency	Mass fraction			Mode classification
	Hz	x	y	z
1	1.7550	0.143	0.000	0.000	1st bending X: vault
3	2.0167	0.000	0.882	0.000	1st bending Y: vault and apse
6	2.4033	0.058	0.000	0.000	2nd bending X: vault and apse
11	2.9619	0.000	0.018	0.001	2nd bending Y: pounding between the apse and the vault
12	2.9705	0.084	0.000	0.000	Apse and SAP slab
16	3.2535	0.000	0.006	0.000	Tympanum