Study On Evacuation Path Planning For Indoor Spaces Of Underground Buildings Taking Into Account The Semantics Of Disaster Situations

Guiding people to escape from accidents in complex public spaces of underground buildings is a complex scientific problem involving the process of spatial data model construction,spatial topological map generation and evacuation path planning,which integrates the interaction of building structure,surrounding environment,human behavior and disaster posture.At present,in the research of emergency evacuation path planning for underground space,most of the studies only consider the path planning and indoor navigation in normalized and static situations,ignoring a series of dynamic changes in the building structure and surrounding environment caused by emergency and sudden disaster situations,which makes the path planning deduction results tend to be idealized and lack practicality,such as changes in the internal circulation state and spatial structure of the building caused by the collapse of the passage,trampling of people or the spread of fire,etc.This makes the path planning results idealized and lack of practicality,such as the scenarios of partial path failure caused by the change of internal access status and spatial structure of the building.To address the above problems,this paper proposes a new idea of indoor crowd evacuation path planning for underground buildings: first,from the functional and structural characteristics of underground buildings,a component-level indoor spatio-temporal data model of underground buildings is designed from three perspectives of geometry,semantics and temporality,highlighting the semantics of disaster situations and oriented to geographic entity objects,and a physical database is formed on the ground;then,on this basis,with the help of constrained Delaunay Finally,a path planning method based on the semantic grid is proposed,and a comparison experiment of various evacuation path planning algorithms is conducted on the indoor evacuation guidance map of underground buildings,and an A*algorithm based on the semantic grid is proposed.The optimization strategy of emergency evacuation path planning based on semantic grid is proposed.The experimental results show that the indoor evacuation guidance map constructed by this method can support the implementation of multiple path planning algorithms,and is feasible and efficient,and shows good adaptability and scalability in evacuation path planning under different emergency disaster scenarios.The research results can provide theoretical basis and technical support for the construction of intelligent evacuation systems in underground spaces,the design of functional structures of underground buildings,the setting of guidance signs and the rapid and reasonable in-place guidance of rescuers.