Damage Index (DI)

Based on the relative differences in modal strain energy, before and after the damage

(15.2)

• Applied to composite, concrete and isotropic beams

Coordinate Modal Assurance criterion (COMAC)

Identifies the co-ordinates at which two sets of the mode shape do not agree

• The COMAC factor at a point between two sets of the same mode shape, in two state is

(15.3)

• Related to degrees of freedom of the structure
• Dependent on the geometry of a structure and the location of a damage
• Applicable to reinforced concrete beam, the wooden board and the isotropic beam