Download - RETC2011 Rostami Kashi
CHALLENGES IN CONSTRUCTION OF URBAN
ROAD TUNNELS, THE CASE HISTORY OF TOHID
EXPRESSWAY TUNNELS IN CENTRAL TEHRAN Jamal Rostami Mohsen Kashi
Penn State University, SRS Engineering,
University Park, PA Tehran, Iran
OUTLINE
Introduction
Tunnel Alignment and Profile
Site Development
Portals and Construction Shafts
Tunneling Operation
Crossing an active Subway Station
Conclusions
South Portal
BACKGROUND
Tehran & Suburbs is the home for over 10 million people
City is spread over an area of around 50 km in the E-W and 30 km in
N-S direction
Tehran has experienced a rapid growth in past 3 decades,
The original fabric is old and does not have sufficient ratio of traffic
space to residential space to accommodate the flow
Streets are congested, slow traffic
2 subway lines are operational, 5 under construction
A network of highways has been constructed around the town
A series of road tunnels are planned to connect the highways
First highway tunnel (Resalat) was completed in 2004 (6 lanes)
2nd one is Towheed, Inaugurated in Feb 2010, 3rd is under
construction for 9 km + a 2000 car capacity underground parking
پروژه تونل توحيد
Project Map
Tunnel
The Least Neighborhood Interference
Fuel Cost
Traffic Congestion
Travel Time
ALIGNMENT & PORTALS
VERTICAL ALIGNMENT
Project North
End Point
Toeheed Shaft North
Portal Jomhoury Shaft
Azadi Shaft South
Portal Project
South End
Point
557-m 310-m 2136-m
Metro Line No. 4
Metro Line No.2
557-m 677-m 496-m 406-m
Work Sites Site Name
1 The North Portal
2 Toeheed Shaft
3 Azadi Shaft
4 Jomhouri Shaft
5 The South Portal
Longitudinal Profile North Ramp Slope 6%
Tunnel Overall Slope 4%
South Ramp Slope 4.29%
TUNNEL PROFILE
GENERAL INFORMATION
Tunnel Height : 8.5-m
Tunnel Width: 13.5-m Each
Overall Project length: 3003-m
The Tunnel Length: 2136-m
Tunnel Cross Section Area: 305-m2
Approach Half-Tunnels North 577-m
South 310-m
Start Date: June 10, 2007
Quantity Unit Activity
750000
m3
Open Excavation
660000 m3 Tunnel Excavation
26000 m Pile Construction
56000 m2 Formwork
25000 Ton Steel Reinforcement
200000 m3 Concrete Placement
450000 m2 Shotcrete Application
250000 m2 Wire Mesh
50000 m2 Precast Concrete Elements
Bill of Quantities
Project Budget ~$400M
INTERFACES WITH OTHER UNDERGROUND STRUCTURES
Subway Line No. 2 (Existing). The longitudinal profile of the tunnel is designed to go under the Subway Station Line No. 2 located around station 2+392 of this tunnel.
Subway Line No. 4 (under construction). The Toeheed tunnel passes beneath the Subway Line No. 4 currently under construction.
Subway Line No. 7 (future construction). The tunnel will essentially run parallel to the No. 7 Subway Line and provisions shall be made in the design and construction of this subway line to assure constructability and other operational issues involved.
Urban Utilities. Several underground utilities including water, gas, electric and telephone lines did interfere with the tunnel and other auxiliary structures such as the shafts, galleries, and the access ramps.
GROUND CONDITION
Mainly course grained soils, gravel/sand
Primarily dry except for certain sections
Intersecting old water works (qanats) Table 1. Borehole/Test Pit Soil Classifications
Borehole Station
(km)
Depths at Tunnel
Section(m) USCS Soil Symbols
BH-1 0+360 5-15 SC/GC-GM/GC
BH-2 0+850 9-18 SC-SM/GC-GM
BH-3 1+070 12-21 GM/GC-GM/SC-SM
BH-7 1+810 20-30 SC
BH-8 1+920 21-30 GC-GM/GM/SC-SM
BH-9 2+150 22-31 SC-SM
Test Pits
TP-1 0+270 0-5 GW/SW/GP
TP-2 0+400 0-10 GP/GP-GM/GW/GP
TP-3 0+520 4-13 GW-GM/GM/GP/GM
TP-4 1+200 15-22 GW/GC/GW
Embedded U-Turn Lane
UNIQUE PORTAL ENTRY DESIGN
HALF ARCH U-TURN LANE
Provides additional traffic lane for U-turn
Allows for easier transition to daylight
MOBILIZATION, SITE PREPARATION
Power House, bar Bending & Batching
Plant
Power House
Equipment
10,000 Ton Cement Silos
Staging Area, Equipment Shops
NORTH RAMP
SITE PREPARATION
Traffic Diversion & Preparatory Work Relocating 600-mm Water main Pipe Traffic Diversion Barriers Road Widening
Supporting 1000-mm Water main Pipe Relocating the military base walls
REDIRECTING
TRAFFIC
CONTINUED HEAVY TRAFFIC
TOEHEED SHAFT SITE
Toeheed Shaft
Chain Bucket
Vertical Conveyor
Lowering the Road Header
Inside the shaft
Towheed Shaft
Side Gallery
Middle Gallery
Inside Towheed Shaft
AZADI SHAFT SITE
AZADI
SHAFT
METRO
Station
Azadi
Shaft Site
AZADI SHAFT 677-M TO TOEHEED SHAFT
496-M TO JOMHOORI SHAFT
AZADI
SHAFT
METRO
LINE
كارگاه شفت
آزادي
Galleries Excavated in the Access Tunnel
from Azadi Shaft
JOMHOORI SHAFT SITE
JOMHOORI
SHAFT
METRO
LINE
Jomhoori
Shaft Site
JOMHOORI SHAFT
496-M TO AZADI SHAFT 406-M TO THE SOUTHERN
PORTAL
Middle Galleries inside the Jomhoori Shaft
گالری های کناری شفت گالری میانی شفت جمهوری
Installing the Pre-cast Lining and Concreting جمهوری
SITE PREPARATION FOR
SOUTHERN RAMP / PORTAL
U Turn
South Portal
Face
km 2.600
South Ramp
28(m)
28(m)
South Ramp Portal Access
گالری میانی فوقانی و تونلهای دسترسی شرقی و غربی
A view of South Ramp at Night
TUNNEL EXCAVATION METHOD
Sequential Excavation Method (SEM)
Excavation of the upper part of the middle gallery
1
Excavation of the Bench, or lower part of the middle gallery
1
2
Excavation of the side galleries
2
1
3 3
Construction of cast in placement of concrete piles Installation of a portion of final lining in the side galleries
3 3 2
1
4
Excavation of the crown region of the tunnels
2
1
3 3
4
5 5
Removing the temporary supports, benching, and completion of crown lining
2
1
3 3
4
5 5
6 6
Excavation of the lower portion of the tunnels
2
1
3 3
4
5 5
6 6
7 7
Completing excavation of the lower parts of the tunnels
2
1
3 3
4
5 5
6 6
7 7 8 8
Installation of Permanent Concrete Forms
and concreting
2
1
3 3
4
5 5
6 6
7 7 8 8 9 9
Drainage Ditch and Base Slab Construction
2
1
3 3
4
5 5
6 6
7 7 8 8 9 9
10 10
Completed Tunnel Profile
Using Conveyor Belt for Soil Removal
Excavation using Roadheader
Excavation using Roadheader
Shotcrete Application
Reinforcing Cages For the Piles
عملیات الینینگ دیواره های کناری عملیات بتن پاشی برای تثبیت دیواره گالری
Installation of Precast Elements
Permanent Linings عملیات بتن پاشی برای تثبیت دیواره گالری
CHALLANGES
CHALLENGES
Crossing the active subway line, under the station
Small footprint for work
Redirecting of traffic
Restriction in access, muck haulage
Fast -Track project, accelerated schedule
Maintaining existing utilities, (i.e. a1.8 m water main)
Dealing with historical waterworks (qanats)
Causing water leakage into the tunnel
Subsidence - sinkhole
CROSSING OF THE ACTIVE SUBWAY
STATION
PROFILE
CROSSING OF SUBWAY STATION
Intersecting Station in
North
Middle
South
ADDITIONAL PROVISIONS FOR STATION
CROSSING
Installation of Invert
beam in the middle
gallery
Heavy grouting of the
lining under the station
MODELING AND ANALYSIS
Numerical Modeling of Sequential Excavation
under the station
GROUND REACTION MODELING
RESULTS
Max measured settlement at the station was:
COMPLETION OF THE WORK
CONSTRUCTION PROGRESS
FINISHING TOUCHES
VENTILATION AND CONTROL STRUCTURE
UTILITIES & FIT OUTS
Ventilation
Fire protection
Lighting
Communication
Traffic Control
CCTV
Art Works!
UTILITIES & FIT OUTS
70 jet fans, each powered at 30 KW.
North fan combined ventilation equipment: 3 axial fans, powered at 600 KW.
Niyayesh fan combined ventilation equipment: 2 axial fans (to let in fresh air into Tunnel) powered at 410 KW. 4 axial fans (to let out exhaust air from Tunnel) powered at 500 KW.
South portal fan combined ventilation equipment: 3 axial fans powered at 990 KW.
Air purification system at the air entering Niyayesh fans.
Lghts in the Tunnel: 1,064 lights powered at 550 KW.
Length of cables for the utilities: 220 km.
Special and standby power generators
Air pollution monitoring sensors
Smart firefighting system.
Traffic alarms.
Intercom telephones.
Closed-Circuit TV.
Vehicles counter.
Road closure system.
Traffic signs.
Thermal sensors.
FINISHED TUNNEL
FINISHED TUNNEL
INAUGURATION CEREMONEY, FEB 2010
Opening of the project by Citizens / Veterans
Questions ?????
Thank You