TUNNEL VENTILATION AND FIRE SAFETY

A case study of Pir Panjal Tunnel

T-80 of USBRL Project -Hitesh Khanna

Ircon International Limited

PIR PANJAL TUNNEL- AN OVERVIEW

• IRCON INTERNATIONAL LIMITED is the principle execution agency for DHARAM-QAZIGUND-BARAMULLAH section of USBRL project of Northern Railway.

• Pir Panjal Tunnel, between Qazigund and Banihal, is the landmark tunnel of the project, connecting Kashmir Valley to Jammu Region.

• At 11.215 Kms., it is the LONGEST transportation tunnel in India.

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T 80 ON USBRL PROJECT

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T80 SECTION AND PLAN

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• Max Over burden 1100 mts.

• B. G. Rly. S/L Track

• 3 mts. Road

• 48.5 m2 X-Sec Area

• Water Proof

UIC Codex 779-9 R Safety In Railway

Tunnels

• To the Extent That Safety is regulated at National level, it shall be defined by National Authorities.

• General Principles: 1. Prevent Accidents

2. Mitigate the Impact of accidents

3. Facilitate ESCAPE

4. Facilitate Rescue 6

UIC Codex 779-9 (contd…)

• Tunnels:

– Minimal Avalanche, Landslides, L-Xing accidents.

– Accidents/Train Km is lower, but critical (Fire)

• For General Public, psychologically, Risk perception is higher for Tunnel Accidents – (LOW FREQUENCY- HIGH IMPACT compared to Level Xing

accidents- HIGH FREQUENCY- LOW IMPACT)

• As FIRE in Passenger Trains is a Major and Specific Risk, the Main Focus is on this type of Accidents.

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UIC Codex 779-9 (contd…)

• Applies to Electrified / Non-electrified Tunnels, and High Rock Cover

• For New Planned Tunnels, longer than 1 Km. but upto 15 Kms. – General Strategy is to get the train out of Tunnel (with

in 15 min. of fire). – Disable Emergency Brakes (operating measures)

• If despite measures, train on Fire comes to stand still inside the tunnel: – Facilitate self ESCAPE to SAFE PLACE – Distance between two safe places not more than 1 Km – Cross passage at not more than 500 mts.

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Ventilation Requirement

• Normal Operation: (Depends on Traction Mode and local conditions):

– Maintain Sustainable Air Quality in side the Tunnel • Pollutant Levels • Oxygen Levels • Temperature

• Emergency Rescue Management: (for both Diesel and Electric Traction- Fire Load may vary)

– Fire and Smoke Management to Assist Emergency Evacuation Strategy

– Fire Effect Mitigation

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VENTILATION SYSTEMS

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• Longitudinal – Air Set in Motion along Tunnel Axis

• Portal to Portal, Same speed though out the Tunnel Length

• No Division into Aerodynamic Segments

• Low Cost, Does not need Transverse air Egress Points

• Time to Purge Foul Air depends on Air Flow Velocity, Tunnel Length

VENTILATION SYSTEMS (contd.)

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• Transverse

– Two Independent Ducts (Fresh Air Inflow and Exhaust air exit)

• Can create Aero dynamic Sections (In case of Fire)

• May Need Transverse Exit Routes (Low Overburden Ventilation Shafts, Stations in Metros

• Costlier to Install, and operate (More Aerodynamic Losses)

VENTILATION SYSTEMS (contd.)

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• Semi-Transverse

– Combination of Longitudinal and Transversal System:

• Separation of Fresh and Exhaust air

• Reversible-

• Fire Case Fresh Air through Portal, Exhaust through Ventilation Stack, Permitting Aerodynamic Separation

• Normally, Fresh air Through Ventilation Stacks

• Larger Tunnel X-Section

VENTILATION SYSTEMS (contd.)

• Considering the merits and demerits of each ventilation system and since there is no station and stop in pir-panjal tunnel; – longitudinal ventilation system has been

considered fit to apply in this tunnel

– worldwide also, only longitudinal ventilation is applied to rail/road tunnel or underground projects.

• Only in underground stations and stops, transversal and semi transversal might be applied.

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Normal Case: Calculation Of Fresh Air Flow

• Para 3.6.2

– Fresh Air Demand due to Gaseous Emissions

– Fresh Air Demand due to Particulate Emissions

– Fresh Air Demand oxygen Depletion (Diesel Engine)

– Normalization Of Temperature (Below 40 deg. C) after passage of 5000T train Uphill

• Ventilation Design (Normal Case- Para 4.0)

– Time to restore Safe Conditions Inside the Tunnel

– Waiting Time for Next Train to enter (after exit of Uphill Loaded Train)

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LOCO MOTIVE EXHAUST DATA

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emission

g/kWh ORE UN UIC

US EPA

(line haul

locomotive,

Tier 0)

WDM2/ALCO

2530HP

WDM3A/AL

CO 3073HP

WDM4/ALCO

4000HP

CO 3 6.7 3 6.71 0.52 0.72 0.56

NOX 12 12.7 10 10.73 13.56 12.42 7.62

Particle 0.5 0.8 0.25 0.30 ??? ??? 0.39

measured emission dataStandards

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STANDARD THRESHOLD POLLUTION LEVEL

American Conference of Governmental and Industrial Hygienists and Continuous Limit for working environment. (Ref. DPR)

1) Long Term Sustainable Threshold Values for Industrial Working Environment (8 hours working)

2) Non-Continuous Exposure, with intermittent Air Exchange

3) Limits up-to 15 minutes exposure

(1) (2) (3)

CO 50 75 400

NO 25 37.5 35

NO2 5 5 5

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Design

Limit

Pir Panjal

CO 50 ppm 200 ppm 50 ppm

NO 25 ppm 35 ppm 90% of NOx

NO2 4 ppm 5 ppm 10% of NOx

Sum: NOx 29 ppm 40 ppm 25 ppm

CO2 5000 ppm 10000 ppm 5000ppm

SO2 5 ppm 5 ppm 5ppm

Particulates

(PM)Not defined Not defined

< 0,012m -̂1

(extinction

coefficient)

Temperature 40°C 50°C for a train passing, max.65°C -

Element8 Hours

Exposure15 Min. Exposure

ADOPTED THRESHOLD ENVIRONMENT PARAMETERS

Page 18

Ventilation Requirement with Electric Traction

► No ventilation required for regular operation

► Fire load for electric locomotives < Diesel powered ones

►

According to design procedure and UIC

→ fire load depends on type of train

→ typical criteria *:

● Diesel → Peak 20 MW

● Electric → Peak 12 MW

● Passenger train → Peak 25 MW

● Freight train → Peak 8-52 MW (depending on load)

► Chosen design criteria → 40 MW

► Electric traction does not impact ventilation design

* According to Deutsche Bahn AG

Thermo Dynamic Data

ITEM REFERENCE Geothermal Heat Input Depending on Parent Rock Temperature and Temp. Gradient to Tunnel Rock Surface

Para 3.2.2

Temperature, Pressure and Density Gradient of Air Inside the Tunnel

Para 3.2.2.1

Portal Meteorological Data Para 3.2.3

Portal Temperature, Wind Pressure, Natural Buoyancy Pressure and Pressure Differential between the Portals

Para 3.2.3.1, 3.2.3.2, 3.2.3.3, 3.2.3.4

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Aero Dynamic Data

ITEM REFERENCE Tunnel Characteristics:

Portal Losses, Tunnel Wall Friction, Wind Velocity at Portals Air Pressure and Temperature Air Density

Para 3.4

Critical Velocity Critical Froude Number Temperature Near The Fire Scene

Critical Velocity to prevent Back Layering Constant Air flow to Blow the Smoke away from Passengers Exiting in Other Direction, Drive HC Vapours Away from Fire Source to avoid Flash Over

Jet Fan Installation Factor & Piston Effect Of The Train and Train Data

Para 3.5 & 3.6

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THERMODYNAMICS ...buoyancy…

temperature rise leads to lower density of air warm mass of rock

heat of train

…. and to longitudinal velocity - chimney effect

a thermodynamic effect

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...wind pressure and meteorological effects...

T u n n e l

wind pressure effect depends on:

- meteorological situation

- tunnel data wind pressure

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Ventilation Design Approach Natural velocity achieved inside tunnel :

AERODYNAMICS ...piston effect …

T u n n e l

depends on: for the Pir Panjal tunnel

the piston effect leads to:

• longitudinal velocity of about 5.34 m/s

• fresh air of about 241 m3/s

- ratio between tunnel and train cross section area

- tunnel resistance: length of tunnel, wall friction and others

- speed of train and aerodynamic drag

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Boundary Condns. (Geometry)

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Description Details

Tunnel length 11.215 m

Length from Banihal Station to South

portal

1450 m

Length from North Portal to

Qazigund Section

4774 m

Finished cross section 48.50 m2

Average elevation above sea level 1734.75 m

Boundary Conditions (Geometric Data)

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Train with 40 km/h needs about 17 min to pass tunnel

l o n

g i

t u

d i

n a

l v

e l

o c

i t

y

longitudinal velocity

-5,00

-4,00

-3,00

-2,00

-1,00

0,00

1,00

2,00

3,00

4,00

5,00

0 60 120 180 240 300

time [min]

[m/s

]

TRAIN SIMULATION TO ASSESS VENTILATION NEED

For normal operatrion

No artificial ventilation is needed

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What happens if a tunnel fire occurs ?

even in the upstream direction against the longitudinal velocity!!

the tunnel roof fills with smoke

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Ventilation For Fire and Smoke Management

Ventilation For Fire and Smoke Management

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• Avoid Backlayring

– Critical Velocity of Airflow to be Maintained

• Smoke To Be Directed, to Permit Escape in other direction

"BACKLAYERING

Stratification Of Smoke

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• Smoke Rises to Top

– Permits Escape Underneath in cooler air

– Flashover Control

• Typically Stratification lasts for 500-800mts

– 30-40 MW fire

– Tunnel Geomtry, Slope

– Air Flow Conditions

VENTILATION DESIGN INPUTS SMOKE CONTROL

• Input Parameters

– What is the maximum size of any fire, which may reasonably be expected to occur, given the use of tunnel

• (Design Fire Curve- Fire/Smoke Vs. Time)

– What Corresponding Ventilation is required to prevent smoke Backflow

• Critical Velocity to be attained

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• Select Design Fire Load: Investigations were performed by Deutsche Bahn AG – Diesel Loco → Peak 20

MW – Electric Loco → Peak 12

MW – Passenger train → Peak

25 MW – Freight train → Peak 8-

52 MW (depending on load)

• Design Fire Adopted 40 MW (Two Dsl. Loco in Tandem)

Emergency Ventilation Design Fire

TEMPERATURE / SMOKE PROGRESSION ALONG THE LENGTH HEIGHT

Computation fluid dynamics (camatt)

– Design Fire

– Tunnel Geometry

– Fan design & Configuration

– Thermo Dynamics

– Fluid Dynamics 33

Emergency Ventilation Design Approach:

TEMPERATURE / SMOKE PROGRESSION ALONG THE LENGTH HEIGHT BY NEAR FIRE CONDITIONS BY 3DCFD Objective:-

– To clarify condition d/s of fire

– Influence of longitudinal flow velocity on the tenability d/s from fire

– Design Fire load 25 MW – Smoke plum should remain

2.5m above rail level during self evacuation time

– Use of Deutsche Bahn Fire curve for smoke release rate and critical velocity

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Emergency Ventilation Design Approach:

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FINAL VENTILATION DESIGN

Jet Fan (Main Tunnel)

Jet Fan (Access Tunnel)

Ventilation Actuation:

Visibility detection

Airflow measurement

Automatic operation

Basic ventilation

Visibility data

Airflow direction

Wind speed

Fire Ventilation

Fire Alarm

Visibility data

Airflow direction

Wind Speed 36

Ventilation System -Installations Sr.No. Description of Items Qty. Location Fixing height Spacing

1 Jet Fan

a) Main tunnel ( Five Groups) 25 MVS 3.5 Mtrs. 150Mtrs.

b) Adit Tunnel 3 Adit 4.0 Mtrs. 150 Mtrs

2 Air Velocity Measuremnt. 21 Each next MN 4.0 Mtrs. 500 Mtrs.

3 CO/Dust Particle 21 Each next MN 4.0 Mtrs. 500 Mtrs.

4 Proximity Sensor

a) Main tunnel 25 Each Jet fan 150 Mtrs

b) Adit Tunnel 3 Each Jet fan 150 Mtrs

5 PT 100 Unit (Temp Sensor)

a) Main tunnel 75 Each Jet fan (3) 150 Mtrs

b) Adit Tunnel 9 Each Jet fan (3) 150 Mtrs

6 Vibration Sensor

a) Main tunnel 25 Each Jet fan 150 Mtrs

b) Adit Tunnel 3 Each Jet fan 150 Mtrs

7 ADIT Axail Fan 2 Adit tunnel 3.0 Mtrs. 4.0 Mtrs. 37

E&M System

Consists of the following

433/250V – 50 Hz Power Supply

Emergency Power Supply

Earthing & Potential Equalisation System

Tunnel Lighting

Tunnel Fittings

Fire Detection System

Building Power & Lighting Installations

Room Ventilation & Air Conditioning 38

Redundant Power Supply ~ I-67, I-65

CCTV System I-68

Emergency and Service Phone

System I-42

Tunnel Radio System I-66, I-2

Public Address System (Speaker

System) ~

Fire Detection System

Fire Fighting System (Water Line,

Extinguishers)

I-24, I-64

Ventilation System I-25

Emergency Lighting I-41

Control Centre ~

Escape Distance to be not more than

1000 mts.

I-43

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System Compliance World Standard

Pir Panjal Comments UIC

~

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T-80 TUNNEL CONTROL MONITORING CENTRE

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MULTI SCRN TUNNEL VIDEO MNTRING - WITH MOTION SENSOR TRIGGERS

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CCTV MONITORING

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VENTILATION FUNCTION

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ESS FUNCTIONING SCRN

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LIGHT & EROS MONITORING

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EVENT LOG

VENTILATION CONTROL STRATEGY REQUIREMENTS TO THE STAFF (NORMAL

OPERATION) Train staff

►Report about type and direction of train

entering the tunnel

►Break down: Report the location of the break

down

Control center staff

►Know about train type and direction

►Monitor emission levels in the tunnel

►Monitor appropriate operation of ventilation

►Instruct the train driver to shut down engines (if

necessary) 47

Ventilation Control Strategy Requirements to the staff (emergency operation)

Train staff

►Guide passengers in the right direction

►Communicate and Local Guidance for Passenger

Rescue

Control center staff

►Select and confirm the appropriate mode of

operation

►Monitor the appropriate mode of ventilation

►Support rescue operation (e.g. coordinate the

rescue train)

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• Detailed Design Consultants – M/s Geoconsult-

RITES JV

– Overall Tunnel Design and Top level Supervision, observations based On-site design with NATM approach

– Ventilation, Rescue, E&M Design

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• HBI Haerter

– Ventilation Design Proof Check

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MAIN TUNNEL

ESCAPE TUNNEL

CROSS-PASSAGES

RAILWAY TUNNEL (T-74R) LAYOUT (AS PER UIC 779)

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