Effect of Ground Motion Directionality on Fragility Characteristics of a Highway Bridge

Table 2

Damage states and threshold rotational ductility demands for the bridge piers.

Damage States	Description of damage states [25]	Threshold rotational ductility demand [26]
None	No damage to a bridge	—
Slight	Minor cracking and spalling to abutments, hinges, piers or minor cracking to the deck	3.39
Moderate	Any pier experiencing moderate cracking and spalling (pier structurally still sound), any connection having cracked shear keys or bent bolts, or moderate settlement of the approach	4.75
Extensive	Any pier degrading without collapse (pier structurally unsafe), any connection losing some bearing support, or major settlement of the approach	8.43
Complete	Any pier collapsing and connection losing all bearing support, which may lead to imminent deck collapse	—