Spatiotemporal state assessment for the underground pipe gallery: Physical model and experimental verification

Understanding the fire safety of underground pipe galleries is attracting more and more attention recently, since it may further trigger heavy economic losses for society. An effective and accurate temperature prediction model for the cable cabin in the underground pipe gallery is critical to describe the temperature evolution and make state assessment. In this study, a spatial-temporal temperature propagation model is established based on the heat conduction equation to reveal the temperature evolution from the perspective of spatial and temporal domains in a concurrent way. To demonstrate the effectiveness of the proposed model, a series of full-scale fire tests are carried out in the largest underground pipe gallery platform in China. The characteristics of fire development can be well captured using the proposed model. The feasibility of the proposed model is demonstrated by analyzing the temperature propagation of spatial and temporal domains. The predictions obtained from the proposed model matched well with the observations measured by sensors, and the temperature spatial-temporal evolution can be depicted precisely. The present work positively provides technical references for state assessment of the underground pipe gallery and making fire protection and intervention strategies, can be applied in other fire scenes with its universality.