Resilience is an emerging concept for analyzing the dynamic performance of critical infrastructures during the post-disaster recovery process. Although a number of studies examined how to assess long-term resilience (1 year +), very few have investigated short-term resilience (few days to several weeks following a disaster). This study presents the new concept of ‘emergency resilience’ and the framework for assessing this short-term resilience for urban lifeline systems in the emergency recovery stage. This framework can quantify differences in system performance (pre-disaster vs. post-recovery) using the new ‘recovery degree’ feature. It also integrates a new performance response function which is based on network equilibrium theory to assess emergency resilience in both the technical and organisational dimensions. In the case study of the water pipeline network in Lianyungang, China, the results showed that the levels of the recovery budget b and recovery resource r had different effects on emergency resilience R in seismic disaster. Furthermore, it is demonstrated how the concept and its assessment framework can provide a quick reference tool for optimal decision-making under various scenarios. This study also examined the effects of two anti-seismic reconstruction measures, namely meshed expansion and ductile retrofitting, on the expected emergency resilience of the water pipeline network.
Water distribution network (WDN) is critical to the city service, economic rehabilitation, public health, and safety. Reconstructing the WDN to improve its resilience in seismic disaster is an important and ongoing issue. Although a considerable body of research has examined the effects of different reconstruction strategies on seismic resistance, it is still hard for decision-makers to choose optimal resilience enhancing strategy. Taking the pipeline ductile retrofitting and network meshed expansion as demonstration, we proposed a feasible framework to contrast the resilience enhancing effects of two reconstruction strategies—units retrofitting strategy and network optimization strategy—in technical and organizational dimension. We also developed a new performance response function (PRF) which is based on network equilibrium theory to conduct the effects comparison in integrated technical and organizational dimension. Through the case study of municipal WDN in Lianyungang, China, the comparison results were thoroughly shown and the holistic decision-making support was provided.
1 December 2019 in Tunnelling and Underground Space Technology