Pipeline Vulnerability of Adapazarı during the 1999 Kocaeli, Turkey, Earthquake

Vulnerability of water pipelines in the city of Adapazarı during the 1999 Kocaeli earthquake (Mw = 7.4) is investigated in an attempt to provide a comparison of the observed damage with that which was predicted using empirical methods. The water supply pipeline system in Adapazarı experienced extensive damage during the 1999 earthquake. The main damage was observed on the distribution pipelines primarily due to ground deformations associated with liquefaction and softening of alluvial sediments. Recently, an updated pipeline damage inventory was compiled based on repair reports and interviews with waterworks personnel who worked in Adapazarı during that period. Vulnerability analysis for pipelines is carried out, first by evaluating earthquake characteristics on the ground surface based on site-specific response analyses and then by estimating pipeline damage by means of empirical functions. Agreement between the predicted and the observed damage distribution indicates the importance of site-specific permanent ground deformation (PGD) effects on pipeline vulnerability.