Safety in Underground Stations

Public transport systems form a fundamental part of our cities and play a major role in our society. Thus, civil safety aspects of underground transport facilities are of crucial importance. Underground stations are generally complex and compact structures where hot smoke can easily infringe escape routes.

This research topic is part of the ORPHEUS project, which aims at complex underground stations. An example is shown below, where two metro lines cross and the platform level are below a shopping level.

Sicherheit in U-Bahn-Stationen
Structure of a multilevel, here three plus surface, underground station

To gain a comprehensive insight of the system's response on different environmental and engineering parameters a design of experiment is created. It covers the underground climate conditions, different fire positions, as well as various heat release rates. The selected fire positions are shown below.

Sicherheit in U-Bahn-Stationen
Fire locations

The modeling of the smoke and heat transport in the station is carried out with the Fire Dynamics Simulator (FDS). The full station model consists of multiple meshes and about 26 million cells with a grid spacing of 15 centimeters. The computations are carried out on the JURECA supercomputer (project jjsc11). The safety assessment is based on multiple tenability criteria. These criteria are evaluated on spacially and temporally resolved maps. The following figure illustrates such a map for a single criterion.

Sicherheit in U-Bahn-Stationen
Spatiotemporal evolution of a tenebility criterion on one of the station's levels at various times (time moves from top to bottom). Red areas indicate regions where the criterion is exceeded.

Further investigations cover the inclusion of the smoke and heat data computed by FDS into pedestrian simulations. An interface to JuPedSim is already developed and applied to compute the required safe egress times.

Publications

Smoke and heat extraction in underground stations
Arnold, L. ; Schröder, B. ; Meunders, A. ; Schmidt, S.
14th International Interflam Conference, Interflam 2016, London, United Kingdom

High parametric CFD-analysis of fire scenarios in underground train stations using statistical methods and climate modelling
Schröder, B. ; Arnold, L. ; Schmidt, S. ; Brüne, M. ; Meunders, A.
10th International Conference on Performance-Based Codes and Fire Safety Design Methods, Gold Coast, Australia

Theses

Multivariate Methods for Life Safety Analysis in Case of Fire
Benjamin Schröder
PhD thesis, 2017

Entrauchung unterirdischer Personenverkehrsanlagen – Eine Untersuchung verschiedener Konzepte mittelshochparametrischer CFD-Simulationen
Sven Schmidt
Master thesis, 2015

Charakterisierung unterirdischer Bahnhöfe hinsichtlich des vorbeugenden und abwehrenden Brandschutzes
Gerald Borchert
Bachelor thesis, 2014

Last Modified: 09.06.2022