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Tunnel and Bridge AssessmentsEastern ZoneCrossrail Line 1 (Limehouse Basin)Doc Ref: 9.15.120

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Thames Tideway Tunnel Thames Water Utilities Limited

Application for Development ConsentApplication Reference Number: WWO10001

TU021 Crossrail Line 1 3 Printed 01/12/2011

Thames Tunnel – Crossrail

Crossrail Running Tunnels (Limehouse Basin) Assessment Report

List of contents

Page number

1 Executive Summary ......................................................................................... 5

2 Description of Works ....................................................................................... 6

2.1 Site Description ....................................................................................... 6

2.2 Asset Description ..................................................................................... 6

2.3 Proposed Thames Tunnel Works ............................................................ 7

2.4 Ground Conditions ................................................................................... 8

3 Assessment ...................................................................................................... 9

3.1 Ground Movement Assessment .............................................................. 9

3.2 Modelling Assumptions .......................................................................... 10

3.3 Analytical Method .................................................................................. 11

3.4 Ground Movement Results and Impact Assessment ............................. 16

4 Conclusion ...................................................................................................... 19

5 Bibliography ................................................................................................... 20

Appendices ............................................................................................................. 21

Appendix A Drawings ...........................................................................................

Appendix B Geology ............................................................................................

Appendix C Extract of Assessment Calculations..................................................

Appendix D List of Assumptions ...........................................................................

Appendix E Transverse Cross-section Movements ..............................................

Appendix F Technical Note on Settlement Parameters in Chalk ..........................

TU021 Crossrail Line 1 4 Printed 01/12/2011

List of figures

Page number

Figure 1: Thames Tunnel – Crossrail crossing at Limehouse Basin ........................... 6

Figure 2: Sketch shows levels used in Ribbon Sink ground movement assessment .. 9

Figure 3: Illustration of longitudinal and transverse assessment .............................. 12

Figure 4: Calculation flow chart for longitudinal strain assessment .......................... 13

Figure 5: Steel fibre reinforced concrete segment M-N Curve for transverse analysis18

List of tables

Table 1: Summary of ground stratigraphy .................................................................. 8

Table 2: Assumed modelling parameters ................................................................. 10

Table 3: Network Rail limits for track vertical profile and track twist (Network Rail, 2009) ....................................................................................................... 12

Table 4: Material strength of concrete ...................................................................... 15

Table 5: Summary of Results ................................................................................... 16

List of abbreviations

Ch Chainage

CSO Combined Sewer Overflow

CRL Crossrail

NR Network Rail

LUL London Underground Limited

TU021 Thames Tunnel reference for Crossrail (Limehouse Basin) damage assessment

K Trough width parameter

khv Coefficient of earth pressure (horizontal:vertical)

TU021 Crossrail – Assessment Report

TU021 Crossrail Line 1 Page 5 Printed 01/12/2011

1 Executive Summary

1.1.1 Atkins has been appointed by the Thames Tunnel Team to carry out an assessment of the potential effects of the project on the proposed Crossrail running tunnels, to assess if early works are required. The location of the crossing is situated north east of Limehouse Basin in the Borough of Tower Hamlets. The tunnels are yet to be constructed, but will be completed prior to the Thames Tunnel construction. This report describes the assessment of likely effects on the Crossrail tunnels from the proposed Thames Tunnel works - an 8.8m diameter bored tunnel, constructed using a closed face tunnel boring machine.

1.1.2 Atkins has completed the assessments based on semi-empirical methods. The ground movement assessment data is based on „Greenfield‟ ground movement assumptions, together with volume loss assumptions and not accounting for soil-structure interaction, which collectively produce a conservative assessment.

1.1.3 Impact assessments which have been undertaken include an analysis of the ground movement effects on the track geometry, as well as longitudinal and transverse assessments of the Crossrail tunnel linings in response to the ground movement predictions. All assessments have been undertaken in line with Network Rail and London Underground Limited Standards acceptance criteria. The settlement assessment indicates that the predicted track settlements, based on conservative assumptions, are within the „No Mandated Action‟ criteria according to the Network Rail limits for track vertical profile.

1.1.4 Assessment of the risk of damage resulting from the construction of Thames Tunnel on the Crossrail running tunnels suggests that the damage impact is within the acceptance criteria adopted for the ground movement effects on the track geometry. The longitudinal damage assessment indicates that the maximum circumferential joint opening is small (less than 1mm). In the transverse assessment, the results indicate that the increase in radial joint opening due to birdsmouthing is approximately 10%, solely caused by Thames Tunnel construction.

1.1.5 Atkins recommends that monitoring of the Crossrail running tunnels prior, during and after the construction of the Thames Tunnel should be undertaken. If an increase in water ingress into the tunnel is noted, caulking at these locations can be used to manage any significant inflow.

1.1.6 Atkins also recommends that the appointed contractor of Thames Tunnel should undertake a pre-construction survey prior to construction of the Thames Tunnel. If, at the time of the pre-construction survey, Crossrail have a contemporary Clearance & Track survey and information on the circularity („squat‟) geometry of the existing tunnel for this section of the line, we recommend that this is used.



2 Description of Works

2.1 Site Description

2.1.1 The Thames Tunnel is planned to cross under the twin bore Crossrail running tunnels to the north east of Limehouse Basin in the Borough of Tower Hamlets. The Crossrail tunnels are yet to be constructed but will have been completed prior to the Thames Tunnel construction. The site location is shown in Figure 1.

Figure 1: Thames Tunnel – Crossrail crossing at Limehouse Basin

2.2 Asset Description

2.2.1 The Crossrail project which is shortly due to commence construction, will be a major new heavy-rail suburban service for London and the South-East, connecting the City, Canary Wharf, the West End and Heathrow Airport to commuter areas east and west of the capital. The main civil engineering construction works for Crossrail are currently underway and are planned to be completed in 2017.

2.2.2 The location of the Thames Tunnel – Crossrail crossing at Limehouse Basin is along Crossrail “Drive Y”, between Limmo and Farringdon. The construction of the Crossrail running tunnels at this location is expected to begin in the third quarter of 2012 and completion is expected in the third quarter of 2014.

Thames Tunnel

Crossrail Westbound

Crossrail Eastbound

Limehouse Basin



2.2.3 The Crossrail running tunnels at this location are to be constructed of 6.20m I.D. bolted segmental concrete lining using an earth pressure balance tunnel boring machine. The tunnel rings will consist of 7 segments and a key. The thickness of the lining will be 300mm and the width of the segments is 1.6m (Atkins, 2011).

2.2.4 The tunnel lining will be constructed of precast steel fibre reinforced concrete segments. The circumferential joints of the standard segments have been designed as flat joints connected by plastic dowels. The radial joints have a convex-convex joint detail connected with spear steel bolts (Crossrail Ltd, 2011).

2.2.5 There are two proposed Crossrail cross passages within the vicinity of the crossing – CP10 and CP11, located approximately 341m northwest and 171m southeast of the Thames Tunnel crossing. There are no proposed Crossrail shafts nearby in accordance with the latest alignment provided (Crossrail Ltd, 2011).

2.3 Proposed Thames Tunnel Works

2.3.1 Information received from the Thames Tunnel team (Thames Water Utilities Ltd, 2011) indicates that the excavated Thames Tunnel diameter is 8.8m, inclusive of overcut. The Westbound and Eastbound Crossrail crossings are skewed by approximately 56o and 53o respectively (an angle of 90o signifies a right angle crossing of the Thames Tunnel to the Crossrail tunnel). See Appendix B for details.

2.3.2 The tunnel crown (extrados) of the Thames Tunnel is at 43.127m ATD and the invert (extrados) of the Crossrail Westbound running tunnel is 68.027m ATD. See Figure 2.

2.3.3 The tunnel crown (extrados) of the Thames Tunnel is at 43.086m ATD and the invert (extrados) of the Crossrail Eastbound running tunnel is 67.839m ATD. See Figure 2.

2.3.4 The minimum extrados-to-extrados clearance between the Thames Tunnel and Crossrail is approximately 24.9m and 24.8m on the Westbound and Eastbound running tunnels respectively.

2.3.5 There are no proposed CSO structures or shafts associated with the Thames Tunnel in the vicinity of the Crossrail running tunnels. If subsequently other structures are identified which may have potential effect on any tunnel under assessment these will be separately considered.

2.3.6 At the time of putting together this assessment report, the current revision of the Thames Tunnel project anticipates passing under the Crossrail Line 1 running tunnels in 2018 to 2019, with the Thames Tunnel TBM driving North East towards Abbey Mills.



2.4 Ground Conditions

2.4.1 The typical geological sequence at the location of the crossing comprises Made Ground, London Clay Formation, Lambeth Group, Thanet Sand Formation and Chalk Group.

2.4.2 The following geology has been assessed based on a geological section for the area undertaken by the Thames Tunnel team (see Appendix B for more details):

Table 1: Summary of ground stratigraphy

Top of Stratum Approximate ground level

Made Ground 107.696 m ATD

London Clay Formation 100.138 m ATD

Lambeth Group 88.352 m ATD

Thanet Sand Formation 69.343 m ATD

Chalk Group 56.590 m ATD

2.4.3 A separate geological desk study has been undertaken by Atkins (Appendix B), which indicates that the geology at the location of the crossing is similar to that presented in Table 1.

2.4.4 The geological desk studies indicate that the Crossrail running tunnels are situated in a mixed face of London Clay and Lambeth Group at the location of the crossing.

2.4.5 At the location of crossing, the Thames Tunnel TBM will encounter the Chalk formation, with the crown a distance of approximately 4.2m beneath the bottom of the Thanet Sand formation.

2.4.6 Whilst the assessment engineers have attempted to determine the most appropriate geology at the tunnel crossing, there is still a possibility of variation in geology along the length of the tunnel. Nevertheless, this stratigraphy is generally consistent with that found elsewhere in London and significant variation over the length of the tunnel can be considered to be unlikely.



3 Assessment

3.1 Ground Movement Assessment

3.1.1 Sub-surface ground movement assessments have been undertaken along the Thames Tunnel alignment. Ground deformations along the alignment of Crossrail have been calculated assuming „Greenfield‟ conditions which do not account for soil-structure interaction or the stiffness of the Crossrail running tunnels.

3.1.2 The presence of Crossrail cross passages CP10 and CP11 noted in Section 2.2.5 have not been considered for the purpose of this phase of assessment as they are beyond the zone of influence of the Thames Tunnel construction.

3.1.3 The ground movement assessments are solely based on short term movement predictions. The impact of long term consolidation movements have been assumed to have negligible impact on the basis that the rate of change of ground slope caused by long term settlement are usually no worse than the „Greenfield‟ settlement trough. The impact of long term settlement increases the apparent trough width factor K such that although the magnitude of settlement increases, the impact of damage is not greater than the short term settlement.

3.1.4 The impact of the pressurised EPB face from the construction of the Thames Tunnel has not been considered in the analysis as it is unlikely to cause significant heave. This will need to be clarified once the final method of tunnel construction has been determined, ensuring that the effects of the face pressure will not be detrimental to the existing tunnel.

3.1.5 The assessment is based on Thames Tunnel Alignment AJ.

Figure 2: Sketch shows levels used in Ribbon Sink ground movement assessment



3.2 Modelling Assumptions

3.2.1 The volume loss (VL) parameter used in the prediction of ground movements at this stage has been determined based on the context of this assessment. A moderately-conservative value of 0.90% for this pre-planning phase has been used in the assessments and reflects the assumed closed-face construction technique. A literature review of the documented recent case histories of tunnel construction in Chalk in the UK is presented in Appendix F, and indicates that this value should be achievable, provided good construction practices are in place. The literature review indicates that the highest value found during review for tunnelling in Chalk in the UK is 0.53%.

3.2.2 Based on our preliminary assessments, a volume loss parameter of 0.9% for the ground movement assessments should ensure that the track geometry in the Crossrail tunnels fall within the “No Mandated Action” criteria. The limiting volume loss value between the “No Mandated Action” criteria and the “Planned Maintenance” criteria is 0.94%. However, it should be noted that the volume loss parameter is not the only factor; the effects of Thames Tunnel construction on the Crossrail track geometry can be attributed to a combination of factors including the trough width parameter and consideration of soil-structure interaction.

3.2.3 Thames Tunnel will also ensure that a specification for the tunnel boring machines (TBM) contract documentation will include a requirement that the TBMs should limit volume loss to 0.90% at the Crossrail-Thames Tunnel crossing.

3.2.4 A trough width parameter, K, of 0.5 is proposed in the assessment of ground movements as being representative of typical ground conditions expected at this site. Experience in London reveals that „K‟ is seldom less than 0.40 (O'Reilly & New, 1982), and also indicates that where VL values of less than 1.0% are achieved, a „K‟ value above 0.50 may be appropriate. The „K‟ value of 0.50 has been adopted for ground movement predictions, and is a conservative assumption.

Table 2: Assumed modelling parameters

Modelling Parameters Value

Volume Loss (VL) % 0.90%

Trough width parameter (K) 0.50



3.3 Analytical Method

3.3.1 The sub-surface movements from bored tunnels were calculated using the semi-empirical „Ribbon Sink‟ method (New & Bowers, 1994).

3.3.2 Horizontal movements were calculated assuming undrained ground conditions, and assume that ground movement vectors are directed towards a „Ribbon Sink‟ at the invert of the Thames Tunnel.

3.3.3 The predicted tunnel-induced ground movements in the x, y and z-directions at the asset location were generated on MathCAD.

3.3.4 From the predicted ground movements, the following impact assessments were undertaken on both the Crossrail Eastbound and Westbound running tunnels:

Track Geometry and Induced Shear Stress

An assessment of the track geometry has been undertaken and includes a check on the vertical profile and track twist. No stiffening effect of the existing structures has been considered and therefore the movement predictions are solely based on the “Ribbon Sink” trough assumptions.

In addition, a check on the track twist induced shear stresses has also been undertaken. Higher rates of rotation are analogous to higher torsional stresses in the slab. The torsional stress has been calculated using the rate of change of rotation and by assuming that the track slab is a simple rectangular beam.

The limit criteria have been based on the values set out in Network Rail Track Geometry and Gauge Clearance (Network Rail, 2009). The assessment assumes that the Crossrail speed range is 100 kph (62.1 mph) along this section of the crossing.



Table 3: Network Rail limits for track vertical profile and track twist (Network Rail, 2009)

Atkins notes that the criteria set out in Tables 2 and 3 assume perfect existing track geometries. If the Crossrail tracks are in place prior to the Thames Tunnel TBM entering the zone of influence, then a Clearance and Track Survey will be undertaken to confirm the track geometry. If a clearance concession is required then all other avenues will need to be explored. The condition of the track will inform the track movement trigger levels.

Figure 3: Illustration of longitudinal and transverse assessment



Longitudinal Assessment of Crossrail tunnels

The longitudinal behaviour of the Crossrail tunnels caused by the transverse settlement trough of the Thames Tunnel has been assessed by calculating the sub-surface movements from bored tunnels using the semi-empirical “Ribbon Sink” method (New & Bowers, 1994). Skew of the tunnel crossing and dip of the Crossrail tunnel alignment have also been taken into account.

The longitudinal tensile strains (combined axial tensile and bending) in the circle bolts and in the skin are calculated by apportioning strains based on the respective relative stiffness. This is done by distributing strains based on the stiffness of a jointed model to the stiffness of a monolithic model. The flow chart below is an indication of the calculation method adopted.

From the resultant longitudinal tensile strains in the circle bolts, an equivalent joint opening has been calculated. A check is also undertaken to determine the effect of the induced tensile stresses in the concrete lining.

Figure 4: Calculation flow chart for longitudinal strain assessment

Calculate „instantaneous‟ radius of curvature from Greenfield assessment

Calculate rotation of joint (for 1.6m segment width) from Greenfield assessment

Calculate bending moments at joint Calculate rotational stiffness of joint

Calculate equivalent EI for jointed system from Engineers‟ Bending Theory

Calculate EI from monolithic structure

Apportion strains based on jointed-to-monolithic structure



Transverse Assessment of Crossrail tunnels

The transverse assessment of the Crossrail running tunnels caused by the longitudinal settlement trough of the Thames Tunnel is detailed in this section.

An initial assessment of the in-situ earth pressure on the tunnel cross section in the existing condition was undertaken based on the closed form solution proposed by Duddeck and Erdmann (Duddeck & Erdmann, 1985) to obtain bending moments and hoop forces. A coefficient of earth pressure (horizontal-to-vertical), khv, of 0.50 has been used in the analysis. The analysis considers both full bonding between lining and ground, and with tangential slip along the lining.

An assessment of the transverse related distortion of the tunnel has been undertaken, caused by the longitudinal cumulative probability S-curve related ground movements as the construction of the Thames Tunnel progresses beneath the Crossrail running tunnels. In order to obtain a comprehensive understanding of the distorted shape of the Crossrail tunnels, the transient effects as the Thames Tunnel passes beneath and ground movements were calculated for a number of points on the tunnel perimeter. The maximum (and transitory) distortion of the tunnel occurs on a diagonal axis as the new tunnel passes beneath the assessed tunnel.

A birds-mouthing assessment of the segmental concrete lining was undertaken by assuming an elliptical deformation of the tunnel. To account for a certain degree of construction (as-built) tolerance, a diametric deviation of 50mm was assumed in the calculations (Crossrail Ltd, 2011), resulting in the presence of some inherent joint rotation immediately after the rings have been erected. By applying a deformation and resulting joint rotation, the increase in joint rotation was determined when distortion due to Crossrail construction tolerance and Thames Tunnel construction is applied. This assessment has been undertaken without consideration of the beneficial effects of the radial spear bolts.

It is our understanding that the Crossrail bored tunnel linings have been designed using finite element analytical substantiation. Whilst this preliminary assessment focuses on the serviceability effects of joint rotation, only the increases in birdsmouthing angle at the radial joints due to Thames Tunnel construction have been presented in this report for the purpose of obtaining Approval in Principle (AiP) for planning purposes.

The eccentricity of the bearing stresses on the radial joint was also calculated and a corresponding moment was obtained. These results are plotted on an M-N diagram to verify that they are within the capacity of the tunnel lining.



The capacity of the steel fibre reinforced concrete (SFRC) segments has been checked in accordance with the RILEM σ-ε design method for SFRC (RILEM, 2003). The table below presents the material properties of the concrete segments used in the assessment:

Steel Fibre Reinforced Concrete (SFRC)

Concrete Grade (Crossrail Ltd, 2011) C50/60

Young’s Modulus (assumed) 16000 N/mm2

Residual flexural tensile strength fR,1 (RILEM, 2003)

4.8 MPa

Residual flexural tensile strength fR,4 (RILEM, 2003)

3.4 MPa

Table 4: Material strength of concrete

The Young‟s Modulus value assumed for this assessment has been taken as a long term stiffness value.



3.4 Ground Movement Results and Impact Assessment

3.4.1 The sub-surface ground movements and trough widths along the alignments of the Crossrail Westbound and Eastbound running tunnels are presented in Appendix C.

3.4.2 The results of the assessments for both the Crossrail Westbound and Eastbound running tunnels are summarised in the table below:

Table of Results

Part 1: Track Geometry Westbound Tunnel Eastbound Tunnel

Maximum settlement 17.2 mm “No Mandated Action”

17.3 mm “No Mandated Action”

Trough width (2 x 3 K z) 74.7 m 74.3 m

Min radius of curvature Sagging

13.68 km

Hogging

29.87 km

Sagging

14.50 km

Hogging

31.64 km

Max gradient of

transverse curve

1:1471 1:1510

Track Twist (per 3m) 0.12 mm “No Mandated Action” 0.12 mm “No Mandated

Action”

Part 2: Longitudinal Assessment

Max tensile strain (instantaneous)

494με 427με

Max tensile strain in segment

(based on 1.6m segments)

0.3με 0.3με

Max tensile strain in joint

(based on 1.6m segments)

494με 467με

Max opening of circle joint 0.79 mm 0.75 mm

Part 3: Transverse Assessment

Max diametric distortion due solely to TT construction

4.1 mm 4.1 mm

Birdsmouth angle at radial joint

Due to CRL tolerance 0.93o (3.4mm) 0.93o (3.4mm)

Due to CRL tolerance + Thames Tunnel construction

1.01o (3.8mm) 1.01o (3.8mm)

Table 5: Summary of Results



3.4.3 On the Westbound running tunnel, the maximum predicted „Greenfield‟ settlement is 17.2, the settlement trough width (6 K z) is approximately 74.7m and the corresponding maximum instantaneous gradient is 0.68mm/m (1:1471). On the Eastbound running tunnel, the maximum predicted „Greenfield‟ settlement is 17.3mm, the settlement trough width (6 K z) is approximately 74.3m and the corresponding maximum instantaneous gradient is 0.66 mm/m (1:1510). The predicted settlement falls into the „No Mandated Action‟ category based on design criteria figures in Table 3.

3.4.4 In the longitudinal assessment of the Crossrail running tunnels, the assessment indicates that the maximum circumferential joint opening at the crown/invert is 0.79mm and 0.75mm in the Westbound and Eastbound running tunnels respectively. These values are caused solely by Thames Tunnel construction.

3.4.5 In the transverse assessment of the Crossrail running tunnels, the maximum distortion of the tunnel rings occurs on a diagonal axis as the Thames Tunnel passes beneath. The maximum diametric distortion due solely to Thames Tunnel construction is approximately 4.1mm on both the Westbound and Eastbound running tunnels.

3.4.6 The birdsmouth analysis indicates that, on the Westbound and Eastbound running tunnels, the radial joint opening is approximately 0.93o or 3.4mm when subjected to Crossrail construction tolerance and 1.01o or 3.8mm when the additional effects of Thames Tunnel construction are taken into account. This is equivalent to an increase of approximately 10% or 0.4mm solely due to Thames Tunnel construction.

3.4.7 Given the geometry of the convex-convex radial joints of the Crossrail segments, it has been determined that at these values of birdsmouth opening (for both cases before and after Thames Tunnel construction), the radial joints have a reduced bearing area as a consequence of hinging about the segment edge. This assessment is based solely on contact mechanics between cylinders assuming elastic behaviour of the concrete radial joints, without accounting for non-linear material behaviour such as elasto-plasticity or development of cracks.

3.4.8 As noted in Section 3.3.4, an analysis of the bearing and bursting stresses in the Crossrail tunnel segments have not been undertaken in this damage assessment. Whilst it is our understanding that the Crossrail bored tunnel linings have been designed using finite element analytical methods, we believe that the analytical methods carried out in accordance to the current scope of works for Thames Tunnel are sufficient to gain AIP for planning unless otherwise directed.

3.4.9 It should also be noted that the transverse effect is a transitory condition as the TBM face passes beneath the crossing and assumes that the tunnel deforms to the shape of the settlement trough without any consideration of soil-structure interaction.



3.4.10 The loads on the tunnel lining from the transverse analysis (for in-situ condition and birds-mouth effect) are within the section capacity and are presented in the figure below:

where W/B and E/B refer to the Westbound and Eastbound running tunnels respectively, and 1.0 and 1.4 are partial load factors applied to the axial force (F) and bending moments (M).

Figure 5: Steel fibre reinforced concrete segment M-N Curve for transverse analysis

0 100 200 300

2 103

2 103

4 103

6 103

8 103

1 104

M-N Curve

W/B 1.4N 1.4M

W/B 1.0N 1.4M

E/B 1.4N 1.4M

E/B 1.0N 1.4M

Crossrail : SFRC M-N Diagram for Induced Birdsmouth

Bending Moments (kNm)

Ax

ial F

orc

e (k

N)



4 Conclusion

4.1.1 The impact assessments of the potential damage to the Crossrail running tunnels which have been undertaken include an analysis of the ground movement effects on the track geometry, as well as longitudinal and transverse assessments of the Crossrail tunnel structure.

4.1.2 Based on the results of the assessment, the damage impact of the construction of the Thames Tunnel on the Crossrail running tunnels is within the acceptance criteria adopted for the ground movement effects on the track geometry. The settlement assessment indicates that the predicted track settlements, based on conservative assumptions, are within the „No Mandated Action‟ criteria according to the Network Rail limits for track vertical profile.

4.1.3 The longitudinal damage assessment indicates that the maximum circumferential joint opening is small (less than 1mm). In the transverse assessment, the results indicate that the increase in radial joint opening due to birdsmouthing is approximately 10%, solely caused by Thames Tunnel construction.

4.1.4 Atkins recommends that monitoring of the Crossrail running tunnels prior, during and after the construction of the Thames Tunnel should be undertaken. If an increase in water ingress into the tunnel is noted, caulking at these locations could be used to manage any significant inflow.

4.1.5 Atkins also recommends that the appointed contractor of Thames Tunnel should undertake a pre-construction survey prior to construction of the Thames Tunnel. If, at the time of the pre-construction survey, Crossrail have a contemporary Clearance and Track survey and information on the circularity („squat‟) geometry of the existing tunnel for this section of the line, we recommend that this is used.



5 Bibliography

Atkins. List of assumptions for Crossrail Line 1 - Thames Tunnel Assessment (Approved by TT). Atkins, London. Rev 02 (2011). British Standard. BS8110-1-1997: Structural use of concrete - code of practice or design and construction. BS8100-1:1997 (1997). Crossrail Ltd. 6.2m ID Standard Precast Concrete (PCC) Lining Segment Details. Crossrail Ltd, London. C122-OVE-C4-DDD-CR001_Z-23160 (2011). Crossrail Ltd. Crossrail response to Atkins RFI 315-OQ-TPI-TU000-000017. Section KT 10 (KT10.4219) (2011). Crossrail Ltd. Crossrail Running Tunnel Alignment (Limehouse). Crossrail, London. CRL1-XRL-R4-DMA-CR142_Z-00001 (2011). Duddeck, H. & Erdmann, J. On Structural Design Models for Tunnels in Soft Soil. vol 9 (1985). Eurocode 2. Design of concrete structures. General rules and rules for buildings.. BS EN 1992-1-2004 (1992). Guyon, Y. Limit State Design of Prestressed Concrete. (1972). Moss, N.A. & Bowers, K.H. The effect of new tunnel construction under existing metro tunnels. Proceedings of the 5th International Symposium TC28 (2005). Network Rail. Inspection and Maintenance of Permanent Way - Track Geometry and Gauge Clearance. Network Rail, London. NR/L2/TRK/001/C01 (2009). New, B. & Bowers, K. Ground movement validation at the Heathrow Express Trial Tunnel. Tunnelling '94 - Chapman & Hall, London. (1994). O'Reilly, M.P. & New, B.M. Settlement above Tunnels in the United Kingdom - Their Magnitude and Prediction. (1982). RILEM. Test and design methods for steel fibre reinforced concrete. σ-ε design method - Final Recommendation. RILEM TC 162-TDF (2003). Thames Water Utilities Ltd. Crossrail Line 1 interface with Thames Tunnel. (2011).

Appendices

TU021 Crossrail Line 1 Printed 01/12/2011

Appendices

Appendix A Drawings

A.1.1 Sketch and archive drawings

Appendix B Geology

B.1.1 Geological information at the Thames Tunnel – Crossrail Crossing

Appendix C Extract of Assessment Calculations

C.1.1 Graphical output of impact assessment calculations

Appendix D List of Assumptions

D.1.1 List of assumptions for Crossrail Line 1 – Thames Tunnel Assessment (approved by Thames Tunnel)

Appendix E Transverse Cross-section Movements

E.1.1 Cross-section distortion analysis as requested by Crossrail to investigate the systems tolerance between the top of rail and overhead line conductor

Appendix F Technical Note on Settlement Parameters in Chalk

F.1.1 Literature review of documented case studies of tunnel construction in Chalk

Appendices


Appendix A

RE

ST

RIC

TE

D

Various

Ove Arup & Partners Limited

Crossrail General

C122-OVE-C4-DDD-CR001_Z-23160

S4

Bored Tunnels (Alignment and Track)

---

150

100

300

30

118°

150

90

90°

40

160 180

Threaded plastic socket

Caulking groove

in gasket groove

Waterproofing gasket

(Joint Detail - Temporary segments)

150

150

(Joint Detail - Standard segments)

50

suit pin on TBM erector pad

Dimensions of lifting cone to

(Convex / Convex Joint) (Convex / Plane Joint) (Plane / Plane Joint)

3 3

65

10 10

Contact Point

CL

3250

R

CL

Contact Point

65

170

65

3250

R

3100

R

3100

R

65

65

Hydrophillic gasket

contractor

to be proposed by

connector

Plastic dowel

Top Plate and Key SegmentOrdinary Segment and Top Segment Bottom EndRadial Joint Radial Joint Radial Joint

Circumferential Joint Circumferential Joint

3 3

1010

65

Grout Hole Detail

Plate

Top

Segment

Key

30

face of shotcrete infill

steel mesh to be anchored to the

50x50x1.5mm Grade 316 stainless

grommet and washer

M24 Steel bolt with hydrophilic

300

protection mortar

Passive fire

mortar with steel float trowel finishes

Final thin coat of fire protection

50

SFR shotcrete infill

Cast in ferrule

Plastic

25

25

170

165 190

40

90°

140

30

118°


in gasket groove


Caulking groove

Radial Joint

washer to contractors details.

with hydrophilic grommet and

M24 Coarse thread steel bolt

3500R3500R(3500 R

adius a

pplies to this width)

65

5

3500Rjoint surface

Key segment plane

(3500 R

adius a

pplies to this width)

33

5

suit chosen gasket profile.

to be proposed by contractor to

Depth and width of gasket recess

suit chosen gasket profile.

to be proposed by contractor to

Depth and width of gasket recess

65

5

to be proposed by the contractor)

(Steel or plastic grout hole fitment

C300, 305

midpoint of the key.

drawn through the

parallel to a radial line

Plane joint surface

RMSDNL04/04/2011P03

Segment Details

6.2m ID Standard Precast Concrete (PCC) Lining

3

segments.

segments abuting SGI

surface to parallel ring

Plane radial joint

135 min.

135 min.

Grout plug

Cap

Washer

Hydrophilic ring

contractors details.

grommet recess and washer to

with hydrophilic grommet,

M24 Coarse thread steel bolt

Parallel Segment Concrete and SGI

Taper to bolt hole

35

30

Taper to bolt hole

35

30

165 190

40

90°

140

30

118°


in gasket groove


Caulking groove

washer to contractors details.

with hydrophilic grommet and

M24 Coarse thread steel bolt 135 m

in.

Radial Joint(Reinforced Segment)

25NB PN18 PVC Pipe

195

RMSDNL31/03/2011P02

Issue for procurement of segment moulds and TBM

RMSDNLIssued for Information21/03/2011P01

Issue for procurement of segment moulds and TBM

Issued for RIBA F

KH11 C122-OVE-Z4-RSP-CR001-00005

5. This drawing shall be read in conjunction with Specification No.

General Notes Drawing No. C122-OVE-C4-DDJ-CR001_Z-22100.

4. For SHE information relevant to all C310 tunnel drawings, see the SHE content of

competent contractor will be readily aware.

identified for construction works associated with this drawing other than those which a

considered to be no specific significant health and safety hazards and issues currently

3. Other than the SHE content of the General Notes drawings cited, there are

General Notes Drawing No. C122-OVE-C4-DDJ-CR001-Z-20200.


General Notes Drawing No. C122-OVE-C4-DDJ-CR001-Z-20100.


N.LEIGHTON

P04

P04

S.DORAN

SDNL03/05/2011

R.MCCRAE

RM

Fit for auth

orisation

www.crossrail.co.uk

Rev :

E14 5LQ

London

Canary Wharf

25 Canada Square

Crossrail Limited

Notes

Originator :

Location :

Scale : Drawing and CAD file No :

Title :

Suitability :

DateRev. Description By Chkd App

' Crossrail

Co

py

Ap

pr

ove

d f

or

Desi

gn -

Create

d:

04-

MA

Y-

20

11

By :

Auth :

Contract :

@ A1

Chk :

App :

Auth

100-DH-TPI-CROSS-000003_AA uncontrolled when printed

Appendices


Appendix B

!.

!.

!.

!.

!.

!.4204

4201

4009

10353191035067

1035066

10350631035062

10350611035060

1034901

1034900

1034899

1034898

1032405

1032445

10335231033517

1033810

1033814

10338131033812

1033816

1033701

1034783

1034782

1034781

1034780

1034779

1034778

1034777

103477510347741034773

1034771

103477010347681034766

1034714

1034713

1034712

1034711

1034710

1034709

10347071034706

1034705

1034704

10347031034702

1034701

1034522

1034521

1034520

1034169

1034168

10341671034166

10338901033889

10333731032885

1032448

1032447

1032446

1032444

1032443

1032406

1032404

1034032

1033817

1033815

10338111033519

1033518

1033516

1033515

1032403

1032402

1033371

1033370

1033369

1033368

10333671033365

10333641033363

103336210333611033360

1032884

10328831032882

1032881

18699563

15948289

15948287

1594828415948273

15948271

15948270

1594826915948267

15948266

15948265

15948264

15948263

15948262

15948261

15948260

137369531373695213736951

13736950

13736949

13736948

1373694613736945

13736944

137369431373694213736941 13736939

13736937

13736936

13736935

13736934

13736933

13736931

13736930

13736929

1373692813736927

13736926

1373692313736922

13736921

13736920

13736918

13736916

13736914

13736912 1373691113736908

13736876

13736874

1373687313736872

13736871

1373687013736869

13736867

13601197

13601196

13601195

13601192

13600995

13600994

13600992

13600982

13600960

13600959

1357683213576831

13576087

13576086

13576063

13576061

13576050

13575994

13575992

13575991

13575976

1357597513575972

1357597113575970

13575965

13575964

1357595713575956

13575954

1357594313575942

13575940

1357593913575938

135754931357549113575489

13575467

13575464

13575463

13575435

13575432

13575404

SR3011

TOWER HAMLETS

TU021 - TfL CrossrailLine 1 Tunnels

Title:

Map Ref : ............................ 1DE03-3P-00007Date : .................................. 2011/09/01Projection : .......................... British National Grid

0 20 40 60 8010

Metres

±

Mapping reproduced by permission of Ordnance Survey onbehalf of HMSO. © Crown copyright and database right 2009. All rights reserved.Ordnance Survey Licence number 100019345

CH2M HILL accept no responsibility for any circumstances,which arise from the reproduction of this map after alteration,amendment or abbreviation or if it issued in part or issuedincomplete in any way.

Area ofmain map

Legend2011 Proposed BoreholesBorehole Type!. Land

!. Water

2009 Drilled BoreholesBorehole Type!. Land

!. Marine

Archive BoreholesHole DepthÜ

0.000000 - 25.000000Û

25.000001 - 50.000000Ù

50.000001 - 400.000000

BGS BoreholesLength

0 - 1010 - 3030+TunnelsAlignment centreline AJLocal Authority Boundary

DRAFT & CONFIDENTIAL

The Point, 7th Floor,37 North Wharf Road,Paddington, London W2 1AF

Thames Water Utilities

This is an indicative working draft plan which has been produced for the purpose of confidential discussions only. Accordingly, the draft plan must not be copied, distributed or shown to any third party without the express written permission of Thames Water Utilities Limited. It provides an indication of sites that, following discussions with local authoritiesand other stakeholders, may be confirmed as being on the shortlist of construction sites for the proposed Thames Tunnel. Inclusion of a site on this draft plan should not be taken to mean that such site will be selected as a construction site to form part of the Thames Tunnel scheme.

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/H

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--TIQT

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TWIQ,

-YYIV-

.,YI.,

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.,PIQP

'UQP7%-Q

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'H

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!!!!.TIQV

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.,PIY.

'UQP7%Y.Y

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-I-N

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.WIPQ

'H

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-.IYT

'7

-TIQP

QW,I,-

.,VINW

'UQP7%PQ,

XH.IPQ

'H

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/&

.YIQ.

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T.PIPT

.,VIVQ

'UQP7%PQQ

XH

WIY-'H

NI.T

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.PI-N

VQQIPW

.,TIVW

110.00110.00

60.00

80.00

50.00

40.00

20.00

70.00

90.00

100.00 100.00

20.00

40.00

50.00

60.00

70.00

80.00

90.00

30.00

yapm1855

Text Box

Chainage (m)

yapm1855

Text Box

Elev. (mATD)

ARCH3332

Typewritten Text

PROJECT REF: TU021 LOCATION: London (Section: Along Crossrail Line 1 Tunnel) CLIENT: THAMES TIDEWAY

ARCH3332

Typewritten Text

ARCH3332

Typewritten Text

TITLE: TU021 - Crossrail Line 1 Tunnel

ARCH3332

Text Box

ENGINEER: RA

ARCH3332

Typewritten Text

ARCH3332

Rectangle

ARCH3332

Typewritten Text

At CRL Westbound approx Thames Tunnel Crown 51.927 mATD

ARCH3332

Typewritten Text

ARCH3332

Typewritten Text

Approx Crossrail Line 1 Tunnel Westbound Invert 68.027 mATD

ARCH3332

Typewritten Text

Direction of Train

ARCH3332

Typewritten Text

Made Ground

ARCH3332

Typewritten Text

Terrace Gravels

ARCH3332

Typewritten Text

London Clay

ARCH3332

Typewritten Text

Harwich Formation

ARCH3332

Typewritten Text

Lambeth Group

ARCH3332

Typewritten Text

Thanet Sand

ARCH3332

Typewritten Text

ARCH3332

Typewritten Text

Chalk

ARCH3332

Group

Legend

.,I,,

&>?;4?=8(6@F

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7&0/%*(L3G;M34:?<(.*-N,,(O8G:;9?<(.*PQ,6!<3::85(:3(79?<8(R3G(S?S8G(A;M8(0TF

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'UQP7%-Q-V

WH

VIQX

/&

.XIXX

/H

Q-IX,

'7

QXI,,

.VI.Y

.,XIX,

'UQP7%-Q-N

WH

QI,,'H

TI.X

/&

.XI,,

/H

-TIV,VYIVV

.,XIYX

'UQP7%-TNN

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TI,, /&!!!!!!!!!!!!!!!!!!!!!!!!!!!TI.,

.,XIVT

YPINV

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WH

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/&

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-NINP

'7

QNIXX

.QPIPQ

.,VI-N

'UQP7%-QQ-

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/&

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Q-IX,

'7

TXIY,&L

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.YXI.,

.,VI.,

'UQP7%-TVV

WH

TIN, L)

.,I.,

/&

.,I,,

/H

--IQ,

-QXIXN

YYIQN

'UQP7%QY,,

6TXI-N@(/F

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!-IT,!!!!!!!!!!!!!!!!!!!!!!!!!!!!!QI.,

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!.YIX,!!!!!!!!!!!!!!!!!!!!!!!!

/H

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!QXIN,

'7

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-TPI,-

.,NITP

'UQP7%PQX

WH

-I.X

'H

NITX

/&

..IV,

QQVIXP

.,YIVV

'UQP7%V.V

WH

-I-Y

/&

.NIPQ

'H

TIT-

/H

-.IVT

'7

-TIQP

QV-IY-

.,XIYN

'UQP7%PQ,

WH

.IPQ

'H

XI.P

/&

.VIQ.

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--IPV

QNVIV,

.,XIXQ

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.,PIQP

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TV.IVY

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Approx

Thames Tunnel Crown

51.927 mATD

110.00

30.00

90.00

80.00

70.00

60.00

50.00

40.00

20.00

100.00

110.00

30.00

90.00

80.00

70.00

60.00

50.00

40.00

20.00

100.00

Approx Crossrail Line 1

Tunnel Eastbound Invert

67.839 mATD

Approx Crossrail Line 1

Tunnel Westbound Crown

74.827 mATD

yapm1855

Text Box

Chainage (m)

yapm1855

Text Box

Elev. (mATD)

ARCH3332

Typewritten Text

PROJECT REF: TU021 LOCATION: London (Section: Along Thames Tunnel) CLIENT: THAMES TIDEWAY

ARCH3332

Typewritten Text

TITLE: TU021 - Crossrail Line 1 Tunnel

ARCH3332

Text Box

ENGINEER: RA

ARCH3332

Rectangle

ARCH3332

Typewritten Text

Chalk

ARCH3332

Typewritten Text

Thanet Sand

ARCH3332

Typewritten Text

Lambeth Group

ARCH3332

Typewritten Text

Harwich Formation

ARCH3332

Typewritten Text

London Clay

ARCH3332

Typewritten Text

Terrace Gravels

ARCH3332

Typewritten Text

Made Ground

ARCH3332

Group

Legend

Appendices


Appendix C

Project: Thames Tunnel Job ref5100812

Part of structure: TU021 Crossrail Line 1 W/B Calc sheet no rev4 AB

Calc ref Calc by Date Check by Date002 MY 16-11-2011

Ref Calculations Output

Greenfield Settlement, Radius of Curvature & Longitudinal StrainsReferences:1. Settlements above tunnel in the United Kingdom - their magnitude and prediction; O'Reilly MP, New BM; Tunneling '82; p.173-1812. " Tunneling in Soil" Ground Movements and their Effects on Structures., P.B.Atwell, R.K. Taylor, eds., Surrey University Press, Champman and Hall, New York, NY, 133-2153. Crossrail Line 1, Interface with Proposed Thames Tunnel, 100-DA-TPI-TU021-810000-AA

CROSSRAIL WESTBOUND TUNNEL

[3] Plan Angle between CRL Tunnel and Thames Tunnel β 56deg

[3] Gradient of CRL Tunnel Gradient 1.0%

Slope α atan Gradient( )

[3] External Diameter of Thames Tunnel Dext 8800mm

[4] Volume loss (%) VL 0.90%

[4] Trough width parameter K 0.5

[3] Invert Level of CRL Tunnel (mATD) ILCT 68.0268m

[3] Invert Level of Thames Tunnel (mATD) ILTT 43.127m ILTT 43.127 m

Depth to Thames Tunnel Invert(from CRL Tunnel Invert)

z ILCT ILTT 24.90 m

Volume loss Vs VL πDext

2

2

Vs 0.547 m2

Plan Section

Output:

S(x,y,z) : The settlement of each point

U(x,y,z) : The x direction-displacement of each point

V(x,y,z) : The y direction-displacement of each point

[1,2] s x y z( )Vs

Dext1 cnorm

x

K z

cnorm2y Dext

2 K z( )

cnorm2y Dext

2 K z( )

u x y z( )Vs K

Dext 2πexp

x( )2

2 K z( )2

cnorm2y Dext

2 K z( )

cnorm2y Dext

2 K z( )

v x y z( )Vs K

Dext 2πcnorm

x

K z

1

exp2y Dext( )

2

8 K z( )2

exp2y Dext( )

2

8 K z( )2

Minimum Radius of Curvature

Calculates minimum radius of curvature (long term) by tracking 3 consecutive points

Setting out calculation points

ystart 6 K z yend ystart calculation length lcalc 10mm

intervalyend ystart lcalc sin β( )

interval 18020.75 i 0 interval Yi

ystart i lcalc sin β( )

xstart

ystart

tan β( ) xstart 50.39 m xend

yend

tan β( ) xend 50.39 m

xinterval

xstart xend

interval X

ixstart i xinterval 500m The -500m considers long term settlement

when settlement trough has fully developed

zstart z ystart tan α( ) zstart 25.65 m zend z yend tan α( ) zend 24.15 m

zinterval

zstart zend

interval Z

izstart i zinterval

Si

s Xi

Yi

Zi

Ui

u Xi

Yi

Zi

Vi

v Xi

Yi

Zi

100 80 60 40 20 0 20 40 60 80 10010

5

0

5

10

15

20

Si

mm

Ui

mm

Vi

mm

Yi

m

Max settlement

max S( ) 17.18 mm

Bending Strains

Note:

lcalc is the distance between calculation points. Set this to very small to calculate instantaneous curvature.

H is the vertical offset between three consecutive calculation points.

From similar triangles, the rotation of the alignment over the three points is 2 γi

Assuming lcalc = lhor, the half angle of rotation γi can be calculated.The sensitivity of this assumption has

been checked and is considered negligible wrt H.

The radius of curvature Radi is then calculated from geometry.

Hi

Hi

Si

Si 1 S

i 1 2

1 i interval 1if

Hi

1 1020

m otherwise

Hi

Set non-zero

γi

asinH

i

lcalc

Radi

lcalc

sin 2 γi

Minhogging A 109

km

A Radi

Radi

A Radi

0kmif

i 0 intervalfor

A

Minhogging 29.87 km

Rad

0

0

1

2

3

4

5

6

7

8

9

12-5.00·106-6.34·106-6.32·106-6.30·106-6.28·106-6.26·106-6.23·106-6.21·106-6.19·10

...

km

Minsagging A 109km

A Radi

Radi

A Radi

0kmif

i 0 intervalfor

A

Minsagging 13.68 km

Bending strain

Assume bending about base of sewer

External diameter of CRL tunnel DE 6.8m DE 6.800 m

εbending_hogging

DE

Minhogging

0.000228εbending_sagging

DE

Minsagging

0.000497

εbendingi

DE

Radi

Axial Strains

Xfi

Xi

Ui

Yfi

Yi

Vi

Zfi

Zi

Si

Lfi

Lfi

Zfi

Zfi 1

2 Xfi

Xfi 1

2 Yfi

Yfi 1

2 1 i interval 1if

Lfi

1 1010

m otherwise

Lfi

Li

Li

Zi

Zi 1 2 X

iX

i 1 2 Yi

Yi 1 2 1 i interval 1if

Li

1 1010

m otherwise

Li

Compression Tension

εaxiali

Li

Lfi

Li

max εaxial 0.000455 min εaxial 0.000211

Combined Strains

Reduction Factor for axial tensile strains RF 0.20

εtotali

εtotali

εbendingi

RF εaxiali

εaxiali

0if

εtotali

εbendingi

otherwise

εtotali

100 50 0 50 1006 10

4

4 104

2 104

0

2 104

4 104

6 104

εtotali

εaxiali

εbendingi

Yi

mMaxstrain min εtotal 497.0 10

6

Project: Thames Tunnel Job ref5100812

Part of structure: TU021 Crossrail Line 1 E/B Calc sheet no rev4 AB

Calc ref Calc by Date Check by Date012 MY 16-11-2011

Ref Calculations Output

Greenfield Settlement, Radius of Curvature & Longitudinal StrainsReferences:1. Settlements above tunnel in the United Kingdom - their magnitude and prediction; O'Reilly MP, New BM; Tunneling '82; p.173-1812. " Tunneling in Soil" Ground Movements and their Effects on Structures., P.B.Atwell, R.K. Taylor, eds., Surrey University Press, Champman and Hall, New York, NY, 133-2153. Crossrail Line 1, Interface with Proposed Thames Tunnel, 100-DA-TPI-TU021-810000-AA

CROSSRAIL EASTBOUND TUNNEL

[3] Plan Angle between CRL Tunnel and Thames Tunnel β 53deg

[3] Gradient of CRL Tunnel Gradient 1.0%

Slope α atan Gradient( )

[3] External Diameter of Thames Tunnel Dext 8800mm

[4] Volume loss (%) VL 0.90%

[4] Trough width parameter K 0.5

[3] Invert Level of CRL Tunnel (mATD) ILCT 67.8393m

[3] Invert Level of Thames Tunnel (mATD) ILTT 43.0862m ILTT 43.086 m

Depth to Thames Tunnel Invert(from CRL Tunnel Invert)

z ILCT ILTT 24.75 m

Volume loss Vs VL πDext

2

2

Vs 0.547 m2

Plan Section

Output:

S(x,y,z) : The settlement of each point

U(x,y,z) : The x direction-displacement of each point

V(x,y,z) : The y direction-displacement of each point

[1,2] s x y z( )Vs

Dext1 cnorm

x

K z

cnorm2y Dext

2 K z( )

cnorm2y Dext

2 K z( )

u x y z( )Vs K

Dext 2πexp

x( )2

2 K z( )2

cnorm2y Dext

2 K z( )

cnorm2y Dext

2 K z( )

v x y z( )Vs K

Dext 2πcnorm

x

K z

1

exp2y Dext( )

2

8 K z( )2

exp2y Dext( )

2

8 K z( )2

Minimum Radius of Curvature

Calculates Minimum radius of curvature (long term) by tracking 3 consecutive points

Setting out calculation points

ystart 6 K z yend ystart calculation length lcalc 10mm

intervalyend ystart lcalc sin β( )

interval 18596.54 i 0 interval Yi

ystart i lcalc sin β( )

xstart

ystart

tan β( ) xstart 55.96 m xend

yend

tan β( ) xend 55.96 m

xinterval

xstart xend

interval X

ixstart i xinterval 500m The -500m considers long term settlement

when settlement trough has fully developed

zstart z ystart tan α( ) zstart 25.50 m zend z yend tan α( ) zend 24.01 m

zinterval

zstart zend

interval Z

izstart i zinterval

Si

s Xi

Yi

Zi

Ui

u Xi

Yi

Zi

Vi

v Xi

Yi

Zi

100 50 0 50 10010

0

10

20

Si

mm

Ui

mm

Vi

mm

Yi

m

Max settlement

max S( ) 17.28 mm

Bending Strains

Note:

lcalc is the distance between calculation points. Set this to very small to calculate instantaneous curvature.

H is the vertical offset between three consecutive calculation points.

From similar triangles, the rotation of the alignment over the three points is 2 γi

Assuming lcalc = lhor, the half angle of rotation γi can be calculated.The sensitivity of this assumption has

been checked and is considered negligible wrt H.

The radius of curvature Radi is then calculated from geometry.

Hi

Hi

Si

Si 1 S

i 1 2

1 i interval 1if

Hi

1 1020

m otherwise

Hi

Set non-zero

γi

asinH

i

lcalc

Radi

lcalc

sin 2 γi

Minhogging A 109

km

A Radi

Radi

A Radi

0kmif

i 0 intervalfor

A

Minhogging 31.64 km

Rad

0

0

1

2

3

4

5

6

7

8

9

12-5.00·106-6.67·106-6.66·106-6.63·106-6.61·106-6.59·106-6.57·106-6.55·106-6.53·10

...

km

Minsagging A 109km

A Radi

Radi

A Radi

0kmif

i 0 intervalfor

A

Minsagging 14.50 km

Bending strain

Assume bending about base of sewer

External diameter of CRL tunnel DE 6.8m DE 6.800 m

εbending_hogging

DE

Minhogging

0.000215εbending_sagging

DE

Minsagging

0.000469

εbendingi

DE

Radi

Axial Strains

Xfi

Xi

Ui

Yfi

Yi

Vi

Zfi

Zi

Si

Lfi

Lfi

Zfi

Zfi 1

2 Xfi

Xfi 1

2 Yfi

Yfi 1

2 1 i interval 1if

Lfi

1 1010

m otherwise

Lfi

Li

Li

Zi

Zi 1 2 X

iX

i 1 2 Yi

Yi 1 2 1 i interval 1if

Li

1 1010

m otherwise

Li

Compression Tension

εaxiali

Li

Lfi

Li

max εaxial 0.000427 min εaxial 0.000198

Combined Strains

Reduction Factor for axial tensile strains RF 0.20

εtotali

εtotali

εbendingi

RF εaxiali

εaxiali

0if

εtotali

εbendingi

otherwise

εtotali

100 50 0 50 1006 10

4

4 104

2 104

0

2 104

4 104

6 104

εtotali

εaxiali

εbendingi

Yi

mMaxstrain min εtotal 469.1 10

6

0 100 200 300

2 103

2 103

4 103

6 103

8 103

1 104

M-N CurveW/B 1.4N 1.4MW/B 1.0N 1.4ME/B 1.4N 1.4ME/B 1.0N 1.4M

Crossrail : SFRC M-N Diagram for Induced Birdsmouth

Bending Moments (kNm)

Axi

al F

orce

(kN

)

Appendices


Appendix D

Assumptions for TU021 Assessment (IT)_15.07.2011.docx

To: Thames Tunnel

From: Michael Yap/Ian Turner Email: [email protected]

Phone: n.a. Date: 15 July 2011

Rev: 02 cc: n.a.

Subject: List of Assumptions for Crossrail Line 1 – Thames Tunnel Assessment

In order to undertake a damage assessment of Crossrail Line 1 due to the construction of Thames Tunnel, the following assumptions are proposed owing to the lack of detailed information received to date:

Item No. Description Assumption

1 Level of Crossrail Eastbound running tunnel - Information received from CRL gives chainage and proposed rail levels in

section – but no chainage makers on plan (Dwg No. CRL1-XRL-R4-DMA-CR142_Z-00001). Insufficient information.

- LTTDT Doc Ref: 315-OQ-TPI-TU000-000017 (15 July 2011) states that

“An updated CAD Crossrail route plan & profile for the tunnels in the vicinity is being updated to include chainages and cross-passage details in profile”

Assume level of Crossrail Eastbound running tunnel is the same as Westbound running tunnel, ie CRL invert extrados 67.350mATD. Thames Tunnel (Alignment AH) levels:

- Crown (extrados) 51.894mATD - Axis 47.493mATD - Invert 43.093mATD

The location of the section cut at the intersection point is based on the drawing provided by Thames Tunnel (Dwg No. 100-DA-TU021-810000)

2 Dimensions of Crossrail running tunnel - Atkins have so far only received information (LTTDT Doc Ref: 315-OQ-TPI-

TU000-000017) on the key segments and radial/circle joint detail from CRL (Dwg No. C122-OVE-C4-DDD-CR001_Z-23160, 161 & 163). These drawings do not give specific information on internal/external diameter of CRL tunnels, segment type, no. of segments per ring, length of ring etc at the location of crossing.

Assume the CRL running tunnels at the location of crossing have the following dimensions:

- I.D. = 6200mm - O.D. = 6800mm - No of segments/ring = 7 segments + 1 key - Length of ring = 1600mm - No. of circle bolts/ring = 22 - No. of radial bolts/segment = 2

3 Properties of concrete segments & reinforcement - No information available on concrete properties (Young’s modulus, poisson

ratio) or reinforcement details

Assume segmental concrete lining has the following properties:

- Young’s Modulus = 16000 N/mm2

Memo



- Poisson Ratio of concrete =0.30 - Assume steel fibre reinforced segments - The characteristic flexural strength of the concrete at the

limit of proportionality (LOP) is assumed to be 5.0 MPa when tested in accordance with BS EN 14651. This Standard describes the method of calculating the flexural tensile strength of steel fibre reinforced concrete (SFRC) and in accordance with RILEM. The method provides for the determination of the LOP and of a set of residual flexural tensile strength values;

- The characteristic residual flexural tensile strength, as defined by a crack mouth opening displacement (CMOD) of 0.5mm, (fR1) is assumed to be 4.8 MPa;

- The characteristic residual flexural tensile strength, as defined by a crack mouth opening displacement (CMOD) of 3.5mm, (fR4) is assumed to be 3.4 MPa

4 Radial Joint Connection – Properties of bolt - Strength (Class) of bolts unknown - From Dwg No C122-OVE-C4-DDD-CR001_Z-23160, bolts are M24 coarse

thread steel bolts. No additional information.

Assume 2No M24 Class 8.8 bolts on double convex radial joints Assume bolt tensile strength = 560 MPa (BS5950-1:2000) Table 34.

5 Longitudinal Joint connections - Information provided in C122-OVE-C$-DDD-CR001_Z-23160 indicates that

plastic dowel connector to be proposed by contractor. Insufficient information.

Assume flat circumferential joints with 3No. plastic dowel Assume Bucklock (or similar) connectors to longitudinal joints http://www.buchanconcrete.com/pdf/BCS_BUCLOCK.pdf

6 Gasket tolerance and movements - Information provided in LTTDT Doc Ref: 315-OQ-TPI-TU000-000017 but

information on material properties is insufficient.

Assumption about tolerance of gaskets to movements - assume the same compression curve as is used in the Bucklock brochure http://www.buchanconcrete.com/pdf/BCS_BUCLOCK.pdf

7 Assessment criteria for track geometry, twist, cant limits - As the Crossrail tunnels are not in operation, there are no assessment

criteria standards. - Atkins have requested from CRL the track performance requirements, but

have yet to receive them as promised.

Assume track geometry, twist and cant limits based on Network Rail Geometry and Gauge Clearance (NR/L2/TRK/001/C01)

8 Fire mains or the catenaries No information on requirements of performance provided therefore a check will not be undertaken.



9 Geology Assumptions on geology based on geological desk study and verified against Thames Tunnel assumed geological cross section

10 Internal structures within tunnel Assume internal features within the tunnel do not significantly affect the stiffness of the tunnel for assessment purposes. (see description for Item No 11)

11 Cross passages - LTTDT Doc Ref: 315-OQ-TPI-TU000-000017 (15th July 2011) states that

“There are no shafts in the vicinity; Cross passage 10 is nearby at approx. Chainage 12580 Eastbound. (evident on the CAD drawing that you have already received)”

Atkins will verify if Cross Passage 10 is within the zone of influence of the assessment to determine if assessment of the cross passage is required. .

Appendices


Appendix E

Technical note on Transverse Movements Rev 2.docx

Technical note

Project: Thames Tideway To: Crossrail

Subject: Response to Comment

- 'Regarding Volume loss'

From: Michael Yap

Date: 25 Nov 2011 cc:

Following the submission of the Damage Impact Assessment of Crossrail Line 1 (Limehouse Basin) due to

the construction of Thames Tideway, Crossrail raised the issue regarding the systems tolerance between the

top of rail and the overhead line conductor, which is particularly sensitive to distortion once installed

(Crossrail, 2011). Discussions with Crossrail have indicated that further work on the prediction of the cross

section distortion of the Crossrail tunnel is required to address this issue, hence the purpose of this technical

note.

Method of Assessment

The same semi-empirical method of ground movement prediction (New & Bowers, 1994) and parameters as

described in the Design Report (Thames Tunnel, 2011) has been adopted in this analysis (VL=0.9% and k-

0.50). The transverse related distortion of the tunnel is assessed by tracking the 3D ground movements of a

number of points on the Crossrail tunnel extrados, taking into account the angle of skew of the crossing.

By monitoring a series of points on the perimeter of the tunnel, the following assessments have been

undertaken:

Assessment of the predicted deformed cross-section shape of the Crossrail tunnel

Gross bulk movement of each point on the perimeter of the tunnel extrados, which gives the

resultant vertical and horizontal movements on each point subjected to Thames Tunnel ground

movements

Net movement of each point on the perimeter of the tunnel extrados, where the net movement is the

difference between the gross bulk movement and the averaged movement at a point on the centre of

the tunnel

Crossrail Eastbound

Crossrail Westbound

Thames Tunnel

+ve V

+ve U -60m

+60m 53o

Figure 1: Sign convention for graphical output in Figure 2


Technical note

Vertical and horizontal movement plots of the Crossrail tunnel extrados are presented in the results section.

Four cross sections have been analysed, 8m apart from the point of crossing. (ie. Y = 0m, 8m, 16m and

24m). This is to take into account the effects of the lateral displacements and to enable the results to be

extrapolated, once the systems of the OLE and spacing of the centenary equipments have been determined.

Figure 2: Ground movement predictions along Crossrail Eastbound

It should be noted that this assessment is based solely on the assumption that the Crossrail tunnel lining

deforms to the shape of the predicted ground movement profile, without any consideration of soil-structure

interaction. The ground is also assumed to behave in an elastic manner, and deformations considered are

caused by the Thames Tunnel with a fully developed settlement trough after the TBM face has passed. The

transient effects of the TBM advance have not been considered in the analysis. Although maximum

distortions could occur in this transient phase as the settlement trough develops, this effect is temporal

based on the assumptions set out above.

60 50 40 30 20 10 0 10 20 30 40 50 6020

15

10

5

0

5

10

SAi

mm

UAi

mm

VAi

mm

8 16

Yploti

24 0


Technical note Deformed Cross-Section Shape of Crossrail Tunnel

– Magnification x100 on both vertical and horizontal movements

4 2 0 2 46

4

2

0

2

4

Distorted Shape

Distorted Shape

Original Crossrail Tunnel


4 2 0 2 46

4

2

0

2

4

Distorted Shape

Distorted Shape



4 2 0 2 46

4

2

0

2

4

Distorted Shape

Distorted Shape



Min diametric distortion -2.48mm

Ma

x d

iam

etr

ic

dis

tort

ion +

3.6

2m

m


Max diametric distortion 3.46mm

Figure1b: Deformed shape of Crossrail Tunnel at Y = 8m

Figure1a: Deformed shape of Crossrail Tunnel at Y = 0m


Technical note


4 2 0 2 46

4

2

0

2

4

Distorted Shape

Distorted Shape



4 2 0 2 46

4

2

0

2

4

Distorted Shape

Distorted Shape



4 2 0 2 46

4

2

0

2

4

Distorted Shape

Distorted Shape



Figure1c: Deformed shape of Crossrail Tunnel at Y = 16m

Max diametric distortion +3.17mm


Figure1d: Deformed shape of Crossrail Tunnel at Y = 24m


Max diametric distortion +2.96mm


Technical note Bulk Movement of Perimeter Points on Crossrail Tunnel


4 2 0 2 46

4

2

0

2

4

Bulk Vertical Movement


Bulk Horizontal Displacement


Tunnel Extrados

Tunnel Extrados

4 2 0 2 46

4

2

0

2

4





Tunnel Extrados

Tunnel Extrados

4 2 0 2 46

4

2

0

2

4





Tunnel Extrados

Tunnel Extrados

-13

.66

mm

-13

.71

mm

-13

.85

mm

-14

.15

mm

-14

.65

mm

-15

.38

mm

-16

.24

mm

-16

.98

mm

-17

.28

mm

-16

.98

mm

-16

.24

mm

-15

.38

mm

-14

.65

mm

-14

.15

mm

-13

.85

mm

-13

.71

mm

Figure2a: Bulk movement of perimeter points at Y = 0m

Figure2b: Bulk movement of perimeter points at Y = 8m

0.00 mm

-0.40 mm

-0.77 mm

-1.06 mm

-1.24 mm

-1.26 mm

-1.06 mm

-0.61 mm

0.00 mm

0.61 mm

1.06 mm

1.26 mm

1.24 mm

1.06 mm

0.77 mm

0.40 mm

-1.17 mm

-1.52 mm

-1.84 mm

-2.11 mm

-2.32 mm

-2.44 mm

-2.43 mm

-2.22 mm

-1.80 mm

-1.24 mm

-0.71 mm

-0.36 mm

-0.23 mm

-0.30 mm

-0.51 mm

-0.82 mm

-13

.06

mm

-12

.70

mm

-12

.46

mm

-12

.38

mm

-12

.58

mm

-13

.11

mm

-14

.00

mm

-15

.10

mm

-16

.07

mm

-16

.56

mm

-16

.46

mm

-15

.93

mm

-15

.25

mm

-14

.58

mm

-13

.99

mm

-13

.49

mm


Technical note


4 2 0 2 46

4

2

0

2

4





Tunnel Extrados

Tunnel Extrados

4 2 0 2 46

4

2

0

2

4





Tunnel Extrados

Tunnel Extrados

4 2 0 2 46

4

2

0

2

4





Tunnel Extrados

Tunnel Extrados

Figure2c: Bulk movement of perimeter points at Y = 16m

Figure2d: Bulk movement of perimeter points at Y = 24m

-11

.40

mm

-10

.74

mm

-10

.17

mm

-9.7

7 m

m

-9.6

4 m

m

-9.8

7 m

m

-10

.56

mm

-11

.65

mm

-12

.93

mm

-14

.02

mm

-14

.59

mm

-14

.58

mm

-14

.16

mm

-13

.53

mm

-12

.83

mm

-12

.10

mm

-2.04 mm

-2.25 mm

-2.44 mm

-2.60 mm

-2.74 mm

-2.86 mm

-2.97 mm

-3.01 mm

-2.90 mm

-2.61 mm

-2.21 mm

-1.84 mm

-1.62 mm

-1.57 mm

-1.65 mm

-1.83 mm

-9.0

8 m

m

-8.2

7 m

m

-7.5

4 m

m

-6.9

5 m

m

-6.5

9 m

m

-6.5

7 m

m

-6.9

6 m

m

-7.7

9 m

m

-8.9

9 m

m

-10

.29

mm

-11

.30

mm

-11

.79

mm

-11

.75

mm

-11

.33

mm

-10

.68

mm

-9.9

0 m

m

-2.44 mm

-2.48 mm

-2.50 mm

-2.51 mm

-2.53 mm

-2.59 mm

-2.71 mm

-2.88 mm

-3.03 mm

-3.06 mm

-2.93 mm

-2.72 mm

-2.52 mm

-2.40 mm

-2.36 mm

-2.39 mm


Technical note Net movement of Perimeter Points on Crossrail Tunnel


4 2 0 2 4

4

2

0

2

4

Net Vertical Movement


Net Horizontal Displacement


Tunnel Extrados

Tunnel Extrados

4 2 0 2 4

4

2

0

2

4





Tunnel Extrados

Tunnel Extrados

4 2 0 2 4

4

2

0

2

4





Tunnel Extrados

Tunnel Extrados

Figure3a: Net movement of perimeter points at Y = 0m

Figure3b: Net movement of perimeter points at Y = 8m

1.3

9 m

m

1.3

5 m

m

1.2

0 m

m

0.9

0 m

m

0.4

0 m

m

-0.3

2 m

m

-1.1

8 m

m

-1.9

3 m

m

-2.2

3 m

m

-1.9

3 m

m -1

.18

mm

-0.3

2 m

m

0.4

0 m

m

0.9

0 m

m

1.2

0 m

m 1.3

5 m

m

0.00 mm

-0.40 mm

-0.77 mm

-1.06 mm

-1.24 mm

-1.26 mm

-1.06 mm

-0.61 mm

0.00 mm

0.61 mm

1.06 mm

1.26 mm

1.24 mm

1.06 mm

0.77 mm

0.40 mm

1.1

7 m

m

1.5

3 m

m

1.7

8 m

m

1.8

5 m

m

1.6

6 m

m

1.1

2 m

m

0.2

3 m

m

-0.8

7 m

m

-1.8

4 m

m

-2.3

3 m

m -2

.23

mm

-1.7

0 m

m

-1.0

1 m

m

-0.3

4 m

m

0.2

4 m

m 0.7

4 m

m

0.21 mm

-0.14 mm

-0.46 mm

-0.74 mm

-0.94 mm

-1.06 mm

-1.05 mm

-0.85 mm

-0.43 mm

0.13 mm

0.67 mm

1.02 mm

1.15 mm

1.08 mm

0.86 mm

0.56 mm


Technical note


4 2 0 2 4

4

2

0

2

4





Tunnel Extrados

Tunnel Extrados

4 2 0 2 4

4

2

0

2

4





Tunnel Extrados

Tunnel Extrados

4 2 0 2 4

4

2

0

2

4





Tunnel Extrados

Tunnel Extrados

Figure3c: Net movement of perimeter points at Y = 16m

Figure3d: Net movement of perimeter points at Y = 24m

0.28 mm

0.07 mm

-0.12 mm

-0.28 mm

-0.41 mm

-0.54 mm

-0.65 mm

-0.69 mm

-0.58 mm

-0.29 mm

0.11 mm

0.48 mm

0.70 mm

0.75 mm

0.67 mm

0.49 mm

0.19 mm

0.15 mm

0.12 mm

0.12 mm

0.10 mm

0.04 mm

-0.08 mm

-0.25 mm

-0.40 mm

-0.43 mm

-0.31 mm

-0.09 mm

0.11 mm

0.23 mm

0.27 mm

0.24 mm

0.0

3 m

m

0.8

4 m

m

1.5

7 m

m

2.1

6 m

m

2.5

2 m

m

2.5

4 m

m

2.1

6 m

m

1.3

2 m

m

0.1

2 m

m

-1.1

8 m

m -2

.19

mm

-2.6

8 m

m

-2.6

4 m

m

-2.2

2 m

m

-1.5

7 m

m -0.7

9 m

m

0.6

4 m

m

1.3

0 m

m

1.8

6 m

m

2.2

6 m

m

2.4

0 m

m

2.1

6 m

m

1.4

8 m

m

0.3

9 m

m

-0.9

0 m

m

-1.9

8 m

m -2

.55

mm

-2.5

5 m

m

-2.1

3 m

m

-1.5

0 m

m

-0.7

9 m

m -0.0

7 m

m


Technical note

Notes:

Sign convention for Figures 2-3

Calculations undertaken for eastbound Crossrail tunnel which is slightly more critical than westbound tunnel. The maximum predicted settlement is 19.2mm and 19.1mm on the eastbound and westbound respectively.

Cross-section of Crossrail tunnels (Figures 1-3) are looking along direction of traffic (i.e. east) on the eastbound tunnel.

Bibliography

Crossrail. (2011, November 3). Email from Geoff Rankin. Subject: Crossrail - Thames tunnel interface - close out of comments. London: Crossrail. New, B. M., & Bowers, K. H. (1994). Ground movement model validation at the Heathrow Express trial tunnel. London: Tunnelling '94. Thames Tunnel. (2011). Thames Tunnel Project - Preliminary Impact Assessment (Crossrail Line 1). 315-RG-TPI-TU021-000001. London: Atkins.

+ve v

ert

ical

+ve horizontal

Appendices


Appendix F

Technical note on settlement parameters in chalk.docx

Technical note

Project: Thames Tideway To: Thames Tunnel/Crossrail

Subject: Detailed Damage Impact Assessment

From: Michael Yap / Rob Sizer

Date: 14 Nov 2011 cc:

Ground movement predictions for tunnelling in chalk

Introduction:

Atkins was appointed by Thames Tunnel Team to carry out an assessment of the potential effects of the

Thames Tunnel construction on the proposed Crossrail running tunnels. At the location of the Thames

Tunnel – Crossrail crossing, the Thames Tunnel TBM will encounter the Chalk formation, with the crown a

distance of approximately 4.6m beneath the bottom of the Thanet Sand Formation.

Figure 1: Geological formations at the Crossrail-Thames Tunnel crossing

An initial damage impact assessment has been undertaken based on semi-empirical methods of ground

movement predictions for tunnelling in soft ground. Sub-surface movements from bored tunnels were

calculated using the ‘Ribbon Sink’ method (New & Bowers, 1994), with a volume loss parameter VL=1.0%

and trough width parameter k=0.50. At the time these were considered to be ‘moderately-conservative’

parameters which reflect the assumed closed-face construction technique and have been shown to be

readily achievable when tunnelling in London Clay and Lambeth Group (Moss & Bowers, 2005), provided

that good construction methods are put in place to ensure good tunnelling practice.

However, following discussions with Thames Tunnel, it has been suggested that these assessment

parameters are potentially not appropriate for assessments of ground movements in the Chalk formation,

notably where the Chalk is competent and unweathered. This note is a summary of the literature review

undertaken by Atkins to determine appropriate conservative assessment parameters of volume loss factors

for tunnel construction in Chalk from documented case histories.


Technical note Case Histories:

One of the challenges in understanding the effect of tunnel-induced settlements from tunnel construction in

Chalk is the limited number of published case histories. The problem of predicting sub-surface ground

movements from tunnel construction in Chalk is complex, and various behaviours have been documented.

For example, a chimney of block ground movements have been noted in shallow cover chalk tunnels

(Watson, Warren, Hurt, & Eddie, 2001), whereas the formation of a stable arch over deep cover chalk

tunnels have been suggested by (Protodyaknov, 1970) and (Terzaghi, 1946).

Owing to the lack of documented case histories and understanding of the behaviour of tunnelling in Chalk, it

is common in the tunnelling industry to adopt the widely recognised semi-empirical method of tunnelling in

soft ground which gives rise to a uniform settlement trough that can be described by an inverted bell-shape

profile. In this technical note, a literature review has been undertaken to determine the appropriate

conservative assessment parameter of volume loss factors for ground movement predictions resulting from

tunnel construction in Chalk formation.

The following case histories of tunnelling in Chalk have been reviewed:

Ramsgate harbour approach tunnel (Bloodworth, Houlsby, Burd, & Augarde, 2002), where a

single bore 11m diameter tunnel was constructed at very low cover in weathered chalk, overlain by

Brickearth and River Gravels

North Downs tunnel (Watson, Warren, Hurt, & Eddie, 2001), where the 8m O.D. CTRL tunnel runs

at depths of up to 100m beneath the chalk hills of the North Downs in Kent

DLR Extension to Woolwich Arsenal (Alder, Dhanda, Hillyar, & Runacres, 2010), where twin 5.3m

diameter running tunnels were constructed through chalk beneath the River Thames

CTRL London Tunnels (Bowers & Moss, 2006), where twin 8.15m excavated diameter tunnels

were driven under east London for the Channel Tunnel Rail Link (CTRL) high speed railway

CTRL Contract 220 (Borghi, 2006) (Wongsaroj, et al., 2006), as above but, in addition, provides

some monitoring data for tunnelling in chalk between Stratford Box and Gifford Street Portal near St

Pancras.

The results from the monitored data from Ramsgate and North Downs are presented in Figure 2. The results

indicate a volume loss of up to 0.4%. Both these tunnels were constructed using the NATM method, and at

Ramsgate, the use of the pre-vaulting technique was adopted where small bores were created and filled with

sprayed concrete prior to tunnel construction.

From the CTRL London Tunnels monitoring, it was noted that throughout much of the route, settlement

volume loss figures averaged around 0.5% (Bowers & Moss, 2006). Where Chalk was encountered at the

tunnel invert, reaching a maximum content of 50% near the Graham Road shaft, volume loss between 0.18%

and 0.53% were encountered (Wongsaroj, et al., 2006).

No specific monitoring data for tunnelling in chalk were provided from Woolwich Arsenal, although the actual

face loss was less than the 1% assumption, with the exception of the drive start-up zone within the

construction worksite

Both the Woolwich Arsenal and CTRL London tunnels were constructed using closed face EPB TBM

machines.


Technical note

Figure 2: Monitored data from Ramsgate, North Downs and CTRL C220 tunnel construction in Chalk

Conclusion:

Based on our findings from the documented case histories we believe that an ‘appropriately conservative’ assessment parameter of 0.9% volume loss can be achieved in chalk at this location, given that best-practices would be in place during the closed-face mechanised TBM construction.

Atkins would recommend to TT that consideration be given as to how during future design development of the tunnelling proposals the specification of works is prepared to ensure that the 0.9% volume loss can be confidently delivered.

0.00%

0.10%

0.20%

0.30%

0.40%

0.50%

0.60%

0.70%

0.80%

0.90%

1.00%

0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00

Vo

lum

e lo

ss

Normalised tunnel depth (depth / diameter)

Tunnelling in Chalk:Relationship between normalised tunnel depth and volume loss


Technical note

Bibliography

Alder, A., Dhanda, D., Hillyar, W., & Runacres, A. (2010). Extending London's Dockland Light Railway to Woolwich. London: Proceedings of the Institution of Engineers.

Bloodworth, A., Houlsby, G., Burd, H., & Augarde, C. (2002). 3D Modelling of the Interaction between Buildings and Tunnelling Operations. Response of buildings to excavation-induced ground movements. London: Proceedings of the International Conference at Imperial College.

Borghi, F. (2006). Soil conditioning for pipe-jacking and tunnelling. Cambridge: University of Cambridge.

Bowers, K. H., & Moss, N. A. (2006). Settlemetn due to tunnelling on the CTRL London Tunnels. London: Taylor & Francis Group.

Moss, N. A., & Bowers, K. H. (2005). The effect of new tunnel construction under existing metro tunnels. Geotechnical Aspects of Underground Construction in Soft Ground.

New, B. M., & Bowers, K. H. (1994). Ground movement model validation at the Heathrow Express trial tunnel. London: Tunnelling '94.

Protodyaknov. (1970). Szechy K, The Art of Tunnelling. Budapest: Akademiai Kiado.

Terzaghi, K. (1946). Rock defects and loads on tunnel supports. Youngstown, USA: Rock Tunnelling with Steel Supports.

Watson, P. C., Warren, C., Hurt, J. C., & Eddie, C. (2001). The Design of the North Downs Tunnels. London: Underground Construction 2001.

Wongsaroj, J., Borghi, F., Soga, K., Mair, R., Sugiyama, T., Hagiwara, T., et al. (2006). Effect of TBM driving parameters on ground surface movments: Channel Tunnel Rail Link Contract 220. London: Geotechnical Aspects of Underground Construction in Soft Ground.


Technical note

Data from Case Studies – Ramsgate and North Downs Tunnels

Location Surrounding

soil

External diameter

(m)

Depth to tunnel

axis (m)

Excavation method

Lining type Quoted volume

loss

Volume loss

(Average) Reference

Normalised depth

Ramsgate Harbour Approach Tunnel

- single bore

Competent Upper Chalk

11 m 11.5 m NATM, Perforex

pre-vaulting method

Sprayed concrete lining with invert slab drilled and grouted sacrificial glass fibre reinforcement

0.15%-0.20%

0.175% (Bloodworth, Houlsby, Burd, & Augarde, 2002)

1.05

North Down Tunnel CTRL Ch 54+477

Chalk

8 m 23.7 m

NATM Reinforced segmental concrete lining

0.18% 0.18%

The design of the North Downs Tunnel (Watson, Warren, Hurt, & Eddie, 2001) Underground Construction 2001

2.96

CTRL Ch 54+600 8 m 22.3 m 0.40% 0.40% 2.79

CTRL Ch 55+970 8 m 94.4 m 0.04% 0.04% 11.80

CTRL Ch 57+100 8 m 102.7 m 0.04% 0.04% 12.84

CTRL Ch 57+375 8 m 36.8 m 0.11% 0.11% 4.60

CTRL Ch 57+585 8 m 25 m 0.29% 0.29% 3.13

CTRL Ch 57+608 8 m 24.3 m 0.30% 0.30% 3.04

CTRL Ch 54+585 8 m 22.4 m 0.15% 0.15% 2.80

CTRL Ch 54+625 8 m 22.4 m 0.44% 0.44% 2.80

CTRL Contract 220 Upper Chalk

8.11 m 35-42m

EPB TBM Reinforced segmental concrete lining

Min 0.18% (Wongsaroj, et al., 2006) (Borghi, 2006)

4.93

Max 0.53% 4.93

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