Effects of Ground Strain and Pipeline Orientation on Pipeline Damage during Earthquakes

Pipeline damage correlations are used for risk studies of water distribution systems. One of the parameters correlated with pipeline damage in permanent ground deformation zones is horizontal (lateral) ground strain. Some damage correlations use the maximum absolute value of the two principal strains around the pipelines as the lateral ground strain parameter. However, strains caused by lateral ground movements can be resolved into components such as axial strains in the direction of the pipelines. Performing such a process for a large urban water distribution system is a relatively complicated task and development of damage relationships requires comprehensive ground deformation and pipeline data. The unprecedented database following the Canterbury Earthquake Sequence in New Zealand (NZ) provides an opportunity to explore the effects of ground strain and pipeline orientation on pipeline damage during earthquakes. This study presents the GIS methodology for using pipeline orientation to evaluate pipeline network damage caused by ground deformation during earthquakes. The geospatial analyses results indicate differences in the responses of asbestos cement (AC) and cast iron (CI) segmental pipelines under compressive and tensile axial strains.