PSI - Issue 78

Yang Liu et al. / Procedia Structural Integrity 78 (2026) 2030–2037

2031

1 Introduction The concept of seismic resilience has recently been employed to explore the post-earthquake behaviour of civil and industrial infrastructure in terms of recovery costs and timescales (Decò et al., 2013; Kalemi et al., 2023). Seismic resilience is generally defined as a system's ability to mitigate hazards, contain the effects of natural disasters and carry out recovery activities in a way that minimises social disruption and mitigates the effects of future earthquakes (Bruneau et al., 2003). While seismic risk is strictly related to the capacity and robustness of a construction in the event of an earthquake, seismic resilience is instead associated with post-earthquake recovery conditions, which typically include direct and indirect economic losses (Bruneau et al., 2003; Bankoff et al., 2004). In this respect, uncertainties relating to seismic vulnerability and the recovery phase suggest using a probabilistic approach to estimate resilience (Decò et al., 2013). The fundamental framework of probabilistic resilience assessment, as proposed by several authors, is illustrated in Fig. 1 (Cimellaro et al., 2010). In particular, conventional seismic risk analysis within the Performance-Based Earthquake Engineering (PBEE) framework forms the basis of the risk assessment methodology. Nevertheless, the seismic resilience of bridges in near-fault regions has not been adequately investigated, despite the fact that near-fault earthquakes can cause severe damage. Consequently, this paper proposes a refined approach for assessing the seismic resilience of bridges in near-fault regions, based on a PSRA approach. The purpose of this study is twofold: To introduce a refined method for assessing the seismic resilience of bridges in near-fault regions. To evaluate the importance of considering near-fault earthquakes in resilience assessments. A representative example is used to compare near-fault and far-field conditions in the resilience assessment. 2 Probabilistic seismic resilience assessment methods The general definition of resilience is the following (Bocchini, et al., 2012):

t T +



0 T

( ) Q t dt T

(1)

t

R

=

0

T

where, R is the resilience; Q ( t ) is the functionality recovery function depending on time t ; t 0 is the occurrence time of the earthquake; T T is the full functionality recovery time interval, which is derived as the summation of the idle time interval T I and the recovery time interval T R . T I and T R are two recovery parameters which directly affect the resilience. The residual functionality Q r at time t 0 and the target functionality Q t , are other two important recovery parameters. Illustration of resilience and recovery parameters is offered in Fig.1.

1

100%

Occurrence probability of near - fault and far - field earthquakes near-fault and far-field

Probabilistic seismic hazard analysis ( PSHA ) analysis (PSHA)

Rapidity

Q r Functionality Q ( t ) Loss

2

Seismic vulnerability under near- fault and far - field ground motions near-fault and far-field

Q t

Seismic fragility analysis ( SFA ) (SFA)

Robustness

t T +



0 T

( ) Q t dt

t

R

=

0

T

Functionality recovery functions for near - fault regions functions for near-fault

3

T

Recovery estimation

T I

T R

0

t 0 +T I

t 0

t 0 +T I + T R

Time t

4

Probabilistic seismic resilience analysis ( PSRA ) resilience analysis (PSRA)

Fig. 1 Fundamental concepts of seismic resilience

Fig. 2 Flowchart of the PSRA in near-fault regions