Seismic Function Evaluation of Urban Water Supply Network and Comparison of Evaluation Indexes

Abstract:

A novel methodology is established for the reasonable seismic function evaluation of urban water supply network from the perspectives of supplying water for daily living and firefighting. First， based on the seismic fragility model of pipelines and the fire risk model of user nodes， the physical seismic damage scenario of water supply network is generated for the target peak ground acceleration. Next， the hydraulic model is modified according to the physical seismic damage scenario of water supply network while the hydraulic adjustment of water flow in the water supply network is performed based on the pressure-dependent demand model. Afterwards， the function of water supply network for post-earthquake daily living and firefighting is evaluated， and the influence of firefighting water demand on daily living water demand is discussed. Finally， the relationship between serviceability indexes and reliability indexes at different peak ground acceleration is revealed. The numerical results show that at the same peak ground acceleration， the evaluation values based on serviceability indexes are greater than those based on reliability indexes. Under the action of small peak ground acceleration （0.2 g and 0.25 g）， both daily living and firefighting water demand can be met at the same time， and firefighting water demand has little effect on daily living water demand. Under the action of large peak ground acceleration （0.40 g and 0.45 g）， due to the serious damage of the water supply network， both daily living and firefighting water demand can not be well satisfied， and firefighting water demand has little impact on daily living water demand. Under the action of medium peak ground acceleration （0.30 g and 0.35 g）， firefighting water demand has a great influence on daily living water demand， about 7 %.