Road Tunnels (eBook)

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