Borghetti / Cerean / Derudi Road Tunnels

An Analytical Model for Risk Analysis
1. Auflage 2019
ISBN: 978-3-030-00569-6
Verlag: Springer International Publishing
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 133 Seiten

Reihe: PoliMI SpringerBriefs

This book illustrates a new quantitative risk analysis model for road tunnels that is capable of evaluating the role of infrastructure measures, equipment and management procedures as prescribed by EU Directive 2004/54/EC. The risk assessment draws on the typical F-N curves of societal risk, evaluated with the help of event tree analysis, vehicle queue formation dynamics, and users' egress and tenability models. In addition, the model considers the reliability of the safety measures. The work provides essential guidance on the following aspects: how a quantitative model can be implemented to evaluate risk in road tunnels; how to build an event tree for the accident scenarios considered; how to simulate the vehicle queue formation; how to simulate the evolution of accident scenarios; and how to simulate the users' egress. Given its scope and depth of coverage, the book will be of interest to all engineers whose work involves fire protection and safety in tunnels, all persons engaged in safety and transport engineering or risk analysis for road tunnels, as well as public and private bodies involved in the application of Directive 2004/54/EC.

Autoren/Hrsg.

Borghetti, Fabio

Cerean, Paolo

Derudi, Marco

Frassoldati, Alessio

Inhaltsverzeichnis

1;Preface;6
2;Acknowledgements;9
3;Contents;10
4;Symbols, Acronyms and Abbreviations;13
4.1;Parameters;13
5;1 Road Tunnels Risk Analysis;19
5.1;1.1 Risk and Its Components;20
5.2;1.2 Risk Analysis Method;21
5.3;1.3 Risk Representation and Acceptance;23
5.4;References;25
6;2 Background of Modelling Approaches and Tools;27
6.1;2.1 QRAM Software;27
6.2;2.2 Theoretical Basis for the Egress Model;28
6.2.1;2.2.1 Pre-movement Time;29
6.2.2;2.2.2 Choice of the Emergency Exit;29
6.2.3;2.2.3 Movement Speed;30
6.3;2.3 Existing Egress Models;30
6.3.1;2.3.1 EvacTunnel;31
6.3.2;2.3.2 GridFlow;31
6.3.3;2.3.3 STEPS;32
6.3.4;2.3.4 PathFinder;32
6.3.5;2.3.5 FDS + Evac;32
6.4;References;33
7;3 Model Structure;35
7.1;3.1 Event Tree Analysis and Frequencies of Occurrence of Accidental Scenarios;36
7.2;3.2 Position of the Accidental Scenarios;42
7.2.1;3.2.1 Probability of Occurrence of Accidents for the Different Positions Along the Tunnel;43
7.3;References;44
8;4 Tunnel Infrastructure Measures, Equipment and Management Procedures;45
8.1;4.1 Interdependence Between the Measures;50
8.2;4.2 Independent Measures;55
9;5 Queue Formation Model;57
9.1;5.1 Queue Formation Speed;57
9.1.1;5.1.1 Time Required for the Queue to Reach the Tunnel Entrance;58
9.1.2;5.1.2 Tunnel Closing Time;59
9.1.3;5.1.3 Distance Between the Vehicles Stopped in the Queue;61
9.1.4;5.1.4 Queue Length;62
9.1.5;5.1.5 Case 1: Queue Length Longer Than the Upstream Tunnel Section;62
9.1.6;5.1.6 Case 2: Queue Length Shorter Than the Upstream Tunnel Section;63
9.1.7;5.1.7 Number of Potentially Exposed Tunnel Users;64
10;6 Distribution Model of Potentially Exposed Users;66
10.1;6.1 Evaluation of the Evacuation Distance;67
11;7 Consequence Analysis of the Accidental Scenarios;72
11.1;7.1 Quantification of the Consequences of the Accidents;73
11.1.1;7.1.1 Computational Fluid Dynamics for Fire Safety and Accident Analysis;74
11.2;7.2 Zone Models;77
11.2.1;7.2.1 Zone Model Software for Tunnel Fires;77
11.3;References;84
12;8 Egress Model of Tunnel Users;86
12.1;8.1 Tunnel Zone Model;86
12.1.1;8.1.1 Analysis of Zone 1—Z1S;86
12.1.2;8.1.2 Analysis of Zone 2—Z2S;88
12.2;8.2 Egress Time;88
12.2.1;8.2.1 Pre-movement Time;88
12.2.2;8.2.2 Movement Time;91
12.3;8.3 Procedure for the Evaluation of Users’ Tenability;93
12.3.1;8.3.1 Comparison Between ASET and Pre-movement Time;94
12.3.2;8.3.2 Dynamic Comparison Between Tenability and Users Egress Times;94
13;9 Calculation of the F-N Curve and the Expected Damage Value;98
14;10 Model Calibration and Validation;101
14.1;10.1 Model Calibration;101
14.2;10.2 Sensitivity Analysis;102
14.2.1;10.2.1 Tunnel Average Daily Traffic—ADT;102
14.2.2;10.2.2 Reference Movement Speed—vbase of the Tunnel Users;103
14.2.3;10.2.3 Reference Recognition and Response Times, and Time Taken to Exit the Vehicle;103
14.2.4;10.2.4 Tenability Threshold Temperature—Tpmax;104
14.2.5;10.2.5 Frequency of Occurrence of Fires and Dangerous Goods Release;104
14.2.6;10.2.6 Effect of the Length of the Discretization Cell;105
14.2.7;10.2.7 Reference Tunnel Closing Time;106
14.2.8;10.2.8 Distance Between the Emergency Exits;107
14.2.9;10.2.9 Number of Positions;111
14.2.10;10.2.10 Percentage of Buses on the Total Traffic and Buses Occupancy Rate;123
14.2.11;10.2.11 Reliability Parameter Tied to Measure Availability;123
14.2.12;10.2.12 Tunnel Infrastructure Measures, Equipment and Management Procedures;124
14.3;10.3 Automation of the Calculation Process;125
14.4;10.4 Comparison with QRAM Software;126
15;Conclusions;131