The document discusses the construction challenges faced during the construction of the Chennai Metro rail project. Some key challenges discussed include: - Tunnelling through varied and unpredictable soil and ground conditions including mixed soil, weathered rock, and fresh rock. This led to variations in cutter consumption and frequency of interventions. - Tunnelling in a dense urban environment with constraints at the surface like buildings, monuments, railway tracks etc. Precise tunnelling control was required. - Breaking into and out of underground metro stations posed challenges due to confinement and ensuring structural integrity of station areas. Specialized tunnelling techniques like drag-through mining were used. - Ground control challenges due to presence

1. INTERNATIONAL SEMINAR ON
MASS RAPID TRANSIT SYSTEM(MRTS)
4th‐5th November 2014
REVIEW AND ASSESSMENT OF CHALLENGES
DURING CONSTRUCTION OF CHENNAI
METRO

2. CONTENT
y PROJECT DETAILS
y PROJECT DESCRIPTION
y GEOLOGICAL AND GEOTECHNICAL OVERVIEW
y TUNNELLING PERFORMANCE (TBM ADVANCE/EXCAVATION)
y TUNNELING THROUGH STATION
y TUNNEL – STATION INTERFACE
y CROSS PASSAGE SOIL TREATMENT

3. DESIGN AND CONSTRUCTION OF UNDERGROUND
AND ASSOCIATED TUNNELS FOR UAA‐01 & UAA‐05
OF CHENNAI METRO
CLIENT :CHENNAI METRO RAIL LTD
GENERAL CONSULTANT :EMBYE
CONTRACTOR :TRANSTONNELSTORY‐AFCONS JV
DESIGNER :PARSONS BRINCKERHOFF
SOURCE OF FUND :FUNDED BY JICA
Total Twin Tunnel Length : 17.5 KM

4. UAA 01
UAA ‐‐ 05
‐ Afcons Project

5. SITE LAYOUT OF THE PROJECT
UAA 01
UAA 05

6. EPBM –– Main Body
20# shove rams

7. Transportation of TBM From Port to Site

8. View of EOT at Washermanpet

9. Tail Skin Lowering for TBM 718 at Shenoy Nagar Station

10. Front & middle Shields ready for lowering into Shaft

11. TBM Assembly

12. Trial of Muck Tilting Divice

13. VIEW OF 1ST TUNNEL ‐ SHENOY NAGAR STATION

14. View of Twin Tunnel

15. Casting shed & View of Commissioned Moulds

16. Segment casting at casting Yard

17. View of Segment stacking

18. Cutter Head / Cutting Tools

19. Sample TBM Data Record
Types of reports/records
•TBM Steering & alignment
•TBM Excavation volume control
•Tunnel grouting records
•Ring survey & orientation record
•Ring build record (steps, cracks,
damage etc)
•TBM Operational Data record

20. Typical Soil Profile ‐ Packages 05

21. Typical Mixed Soil Profile ‐ Packages 01
Ground Level : +2.855
Roof Top level : -0.420
Concourse Level : -6.420
Base Slab Level : -14.135
D-Wall Tip level : -24.600

22. Mixed Ground

23. Typical Rock Soil Profile ‐ Packages 01

24. Soil Profile‐Mannadi Station
Project UAA 01

25. Soil Profile‐ Chennai Central Station
Project UAA 01

26. Core Details

27. Surface Constraints
Saint Andrew’s Church
SHIFTING OF MONUMENT AT RIPPON
BUILDING AREA

28. High Court Mannadi

29. Surface Constraint
Chennai Central

30. Surface Constraint Chennai Central
SHC Shaft

31. Surface Constraint ‐Egmore

32. Surface Constraint - Railway tracks on the stretch High Court –
Chennai Central and geological Profile

34. Surface Constrain - Railway tracks on the stretch
Chennai Central ‐ Mayday Park Tunnel

35. View of Locomotive ‐ Mayday Park
Tunnelling beneath Coovam River
Under Coovam River

36. 100%
TYPICAL GEOLOGICAL PROFILE VARIATION
60%
80%
Percent
age
Expected
W1 W2 W3 W4
20%
40%
0%
4842.0133
4847
4862.9
4880
4891
4903
4910.4
4915
4923
4934
4940
4951
4956
4967
4977
4992
100%
Chainage
60%
80%
entage
Actual Profile
0%
20%
40%
3
7
9
0
1
3
4
5
3
4
0
1
6
7
7
2
Perce
4842.0133
4847
4862.9
4880
4891
4903
4910.4
4915
4923
4934
4940
4951
4956
4967
4977
4992
Chainage W1‐Fresh Rock
W2‐Slightly weathered Rock
W3‐M Weathered Rock
W4‐ Highly Weathered Rock

37. Geological Variation Results:
Cutter Consumption & Frequency of Intervention

38. TBM retrieval in wet condition

39. CHENNAI CENTRAL
(Overlapping of Two Corridor)

40. Retrieval Shaft at SCC ‐ Mayday Park Tunnel

41. Obstacles during Tunnel Operation
Ground Level
CL
Red
Zone
Ora
Zon
Gr
Zone
L
TUNNEL
A
ange
ne
reen Zone
Green Z
Orange
Zone
TUNNEL
B
1.0 mt 1.0 mt
Bore well influence 1mt from Extrados of Tunnel
Segment

42. Obstacles during Tunnel Operation
UAA 01
NO. OF EXISTING WELLS IN DIFFERENT ZONES: UAA01
Project
RED ZONE
(11.355 m.
f T l
ORANGE ZONE
(5.15 m. from RED
GREEN ZONE
( 4.5 m. from
TOTAL R + O +
G
from Tunnel
CL)
5. 5 R
ZONE)
ORANGE ZONE)
Package 01 304 98 90 492
Package 05
61 24 60 145
Total 365 122 150 637

43. BUILDING CONDITION SURVEY
BUILDING CONDITION SURVEY

44. TUNNELLING PERFORMANCE
The TBMS are normally operated on a 24 hr basis, working 2
shifts per day.
The following main results have been achieved:
¾ Average Daily Production:.12 ..Rings =16.8 m
¾¾ Best Day(09/02/2013): 39rings=54.6 m
¾ Best week(04/02/2013 to 09/02/2013): 139 rings=182 m
¾ Best Month ( Oct 2013): 525 rings= 735 m
¾We have achieved 39 Rings Boring in a day first time in
the World
Considering that all the 5 TBMs have been operated in a very sensitive urban
environment, almost always in closed mode, these results can be regarded as very
positive and above the usual standard.

45. Heave pressure verification
3 50
4.00
4.50
5.00
2.00
2.50
3.00
3.50
ressures (bar)
0.50
1.00
1.50
Pr
Cohesive material
0.00
0+220
0+260
0+300
0+340
0+380
0+420
0+460
0+500
0+540
0+580
0+620
0+660
0+700
0+740
0+780
0+820
0+860
0+900
0+940
0+980
1+020
1+060
1+100
1+140
1+180
1+220
1+260
1+300
1+340
1+380
1+420
1+460
1+500
1+540
1+580
CHAINAGE
Heave pressure (by Jancsez th.) Recommended Max. Pressure

46. Recommended EPB pressure and
Grout Injection Pressure
3.00
2.00
2.50
ar)
Pressures (b
1 00
1.50
0.50
1.00
0.00
1+580
1+620
1+660
1+700
1+740
1+780
1+820
1+860
1+900
1+940
1+980
2+020
2+060
2+100
2+140
2+180
2+220
2+260
2+300
2+340
2+380
2+420
2+460
2+500
CHAINAGE
Recommended pressure Min.pressure Max.pressure Grout injection system

47. Earth Pressure Monitoring
3
2.5
2
1.5
1
Pressure (bar)
0.5
0
0 200 400 600 800 1000 1200 1400 1600 1800 2000
Earth P
Mannadi Station Ring No.
D'W ll C tti
High Court
D'Wall Cutting Station Area
3.5
3
2.5
ure (bar)
2
1.5
1
0.5
Earth Pressu
0
0 200 400 600 800 1000 1200 1400 1600 1800 2000
Ring No.

48. Typical Machining Parameters
monitoring
30000
25000
20000
orce
Thrust Force(kN)
3.5
3
2.5
2
M
Cutting wheel Rotation (rpm)
15000
10000
5000
0
0 500 1000 1500 2000
Thrust Fo
1.5
1
0.5
0
0 500 1000 1500 2000
RPM
Ring No.
Ring No.
Torque(MN.m) Advance Speed (mm/Min)
4
3.5
3
2.5
2
que
60
50
40
30
eed()mm/Min.
1.5
1
0.5
0
Torq
20
10
0
0 500 1000 1500 2000
Advance Spe
0 500 1000 1500 2000
Ring No.
Ring No.

49. Operation steps in Mechanized Tunneling
¾Making Launching Shaft
¾¾Assembly of TBM ¾ i i Sh f
¾Initial Drive
¾Muck Out
Receiving Shaft
¾Tunnel Break through
¾Dissemble TBM
¾Boring
¾Assembly of Lining
¾Grouting
¾Segment Lining
¾Close of Launching shaft
upon Completion
¾Retrieval of TBM to Groundt
¾Close of receiving shaft
p p
Segment yard
™Casting of Segment

50. Type of TBM
EPBM‐Mixed Ground Type EPB‐Soft Ground Type
UAA 01
Washermanpet to Chennai
Central
M f t H k ht
UAA 05
Shenoy Nagar to
Thirumangalam
Manufacture‐Herrenknecht Manufacture‐
Herrenknecht
UAA 01
May day Park to Chennai
EPB‐Rock/Mixed Face
Central
Manufacture‐Robbins

51. TBM Confinement

52. Breaking Out Through Confinement

53. Interface Tunnel ‐ Station
Mining Through D Th h
UAA 01 Drag Through
Mining Through Station Trag Through
Break In Break Out Break In Break Out
Break In
Break Out
UAA 05
Mining Through h h
reak
hrough
Drag Through Drag Through
Br
Th
Break In
Break Out Break In Break Out Break In

54. TBM 717 Break In – Anna Nagar TBM Break In Shenoy Nagar Station
Tower
In‐

55. View of 1st Tunnel & TBM 718 ‐ Shenoy Nagar Station

56. Mining Through Station
Plan
Elevation

57. TBM Drag through

58. TBM Break through
717

59. 718
711
710 711 717 710

60. Tunnel Boring Machine Specification
TBM’s
Cost of each TBM & backup equipment 33.5Cr
TBM total weight 290 T
Excavation diameter 6.6 m
Overall length 9.7 m
Electrical power 940 kW
Left & right rotation speed Max 4.57 rpm
Ram advance speed Max. 80 mm/min
Ram jacks 32 #
Total advance thrust force 42000 KN
Earth pressure sensors 6 #

61. Cross Passage Soil
Treatment