Assessing ground interaction effects and potential damage on existing tunnels before and after new excavation works

The research project sought primarily to investigate the effect of tunnelling on existing tunnels with a focus on the behaviour of grey cast iron segmental linings.  This was achieved through field measurements, laboratory testing and numerical analysis. 

Extensive field instrumentation was installed within the Central Line tunnels and the ground in their vicinity where the new 7.1-m diameter Crossrail tunnels passed beneath them.  In the structures laboratory various tests were performed on half-scale segments and a ring using load and displacement control to assess stress and bending moment distributions within the lining as it was distorted to shapes observed in the ground.  Numerous numerical analyses were performed of both the structural testing and the field conditions using ICFEP with its state of the art constitutive models and boundary conditions.  Advanced laboratory testing of high quality samples of London Clay taken during installation of the field instrumentation (at Hyde Park) provided refined soil parameters for the numerical analysis.

The work has provided great insight into the behaviour of existing grey cast iron segmentally lined tunnels under field and controlled laboratory displacement fields. 

Seminar:

On Wednesday 25th April 2018 there will be a half-day seminar to disseminate and discuss findings from the Imperial College Crossrail research project.  The seminar, Effects of tunnelling on existing tunnels, starts at 13:00, it is free and those interested should register with Ms. Sue Feller.   

Publications

More information can be found by reference to some of the publications that have emerged from the project:

Structural testing and analysis

Afshan, S., Yu, J.B.Y., Standing, J.R., Vollum, R.L. and Potts, D.M. (2017).  Ultimate capacity of a segmental grey cast iron tunnel lining ring subjected to large deformations.   Tunnelling and Underground Space Technology, Vol. 64, pp 74-84.

Standing, J.R. and Lau, C. (2017).  Small-scale model for investigating tunnel lining deformations. Tunnelling and Underground Space Technology, Vol. 68, pp. 130-141.

Tsiampousi, A., Yu, J., Standing, J.R., Vollum, R. and Potts, D.M.  (2017).  Behaviour of bolted cast iron joints.  Tunnelling and Underground Space Technology, Vol. 68, pp 113-129.

Yu, J., Standing, J.R., Vollum, R., Potts, D. M. and Burland, J.B. (2015).  Stress and strain monitoring at Tottenham Court Road Station, London, UK.  Proc. ICE – Structures and Buildings, Vol. 168, No. SB2, pp 107 – 117.

Yu, J., Standing, J.R., Vollum, R., Potts, D.M. and Burland, J.B. (2017).  Experimental investigations of bolted segmental grey cast iron lining behaviour.  Tunnelling and Underground Space Technology, Vol. 61, pp 161-178.

Field monitoring

Fearnhead, N., Maniscalco, K., Standing, J.R. and Wan, M.S.P. (2014).  Deep excavations: monitoring mechanisms of ground displacement. Proc. ICE – Geotechnical Engineering, Vol. 167, GE 2, pp 117-129.

Hauswirth, D., Puzrin, A.M., Carrera, A., Standing, J.R. and Wan, M.S.P. (2014).  Application of fibre optic sensors for simple assessment of ground surface displacements during tunnelling. Géotechnique, Vol. 64, No. 10, pp. 837 – 842.

Wan, M.S.P. and Standing, J.R. (2014).  Lessons learnt from installation of field instrumentation to monitor ground response to tunnelling. Proc. ICE - Geotechnical Engineering, Vol. 167, No. GE5, pp 491–506.

Wan, M.S.P. and Standing, J.R. (2014).  Field measurement by fully grouted vibrating wire piezometers. Proc. ICE - Geotechnical Engineering, Vol. 167, No. GE6, pp 547–564.

Wan, M.S.P., Standing, J.R., Potts, D.M. and Burland, J.B. (2017). Measured short-term ground surface response to EPBM tunnelling in London Clay. Géotechnique, Vol. 67, No. 5, pp. 420-445.

Wan, M.S.P., Standing, J.R., Potts, D.M. and Burland, J.B. (2017). Measured short-term subsurface ground displacements from EPBM tunnelling in London Clay.  Géotechnique, Vol. 67, No. 9, pp. 748-779.

Wan, M.S.P., Standing, J.R., Potts, D.M. and Burland, J.B. (2018).  Pore water pressure and total horizontal stress response to EPBM tunnelling in London Clay. Submitted to and under review for Géotechnique.

Numerical analysis

Avgerinos, V., Potts, D.M. and Standing, J.R. (2016).  The use of kinematic hardening models to predict tunnelling-induced soil movements in London Clay.  Géotechnique, Vol. 66, No. 2, pp 106 – 120.

Avgerinos, V., Potts, D.M. and Standing, J.R. (2017).  Numerical investigation of the effects of tunnelling on existing tunnels.  Géotechnique, Vol. 67, No. 9, pp. 808-822.

Avgerinos, V., Potts, D.M., Standing, J.R. and Wan M.S.P (2018).  Predicting tunnelling-induced ground movements and interpreting field measurements using numerical analysis: Crossrail case study at Hyde Park.  Géotechnique, Vol. 68, No. 1, pp. 31-49.

Laboratory soil testing

Ackerley, S.K., Standing, J.R. and Hosseini Kamal, R. (2016).  A system for measuring local radial strains in triaxial apparatus.  Géotechnique, Vol. 66, No. 6. pp 515 – 522.

Funding:

EPSRC (Grant No. EP/G063486/1) and Crossrail with collaboration from Morgan Sindall and LUL.

Academic team:

Dr. Jamie Standing (PI), Prof. David Potts (Co-I), Prof. John Burland (Co-I), Dr. Robert Vollum (Co-I)

Research team: 

Jessica Yu, Michael Wan, Vasilis Avgerinos, Katerina Tsiampousi, Ramtin Hosseini, Sheida Afshan,Khalid Al Haj