Skip to main content

Advertisement

SpringerLink
Log in

Ground Saturation Response During First Filling of Lined Pressure Tunnels: A Case Study

  • Original Paper
  • Published:
Rock Mechanics and Rock Engineering Aims and scope Submit manuscript

Abstract

The Neelum–Jhelum Hydropower Project, commissioned in April 2018 and located in the Azad Kashmir region of northeast Pakistan, is one of the most challenging and technically complex projects in the region. The project’s 28.6 km headrace tunnels are constructed in a highly mountainous region with relatively complex geology that includes various sedimentary rocks of Murree formation. The hydro-mechanical behavior of the deep headrace tunnels with a maximum overburden of 2000 m and underground powerhouse at a depth of 450 m are of particular interest. The project generates electricity by diverting water from the Neelum River to an underground powerhouse through a tunnel system crossing beneath the Jhelum River. The pressurization of the hydraulic tunnels was an important milestone and necessitated intentional planning down to the smallest detail for the first filling. Successful filling was a governing criterion for proper functioning of the tunnel lining that was supplemented by monitoring instruments, a drainage system, and ground treatments during construction of the project. Ground re-saturation during the first filling of the concrete and shotcrete-lined waterways constructed in the diversified rock mass is interesting to study. The rock mass in this area is sheared and fractured, with open fissures. In this study, we investigated the ground re-saturation and water leakages in adits, plugs, and surface outflow after the first filling of the headrace tunnel. A load rejection test was conducted to evaluate overall fitness of the power waterways, plant, and to study any change in leakages due to sudden oscillation in the waterway tunnels. Surfer3D software was used to analyze the data collected from the piezometers, which showed abnormal water pressure built up in a localized zone between penstocks three and four. This study was also supported with two-dimensional finite element modeling of the project, at a location where the tunnel has minimum rock cover susceptible to hydrojacking. Numerical analysis results were compared with field data results during the first filling process and both showed close proximity.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16
Fig. 17
Fig. 18
Fig. 19

Similar content being viewed by others

References

  • Abbasi AH (2014) Pakistan energy vision, 2035, SDPI

  • Esteves C, Plasencia N, Pinto P, Marques T (2017) First filling of hydraulic tunnels of Venda Nova III hydropower scheme. In: Proceedings of the World Tunnel Congress. Bergen, Norway

  • Fernández G (1994) Behavior of pressure tunnels and guidelines for liner design. J Geotech Eng 120:1768–1791

    Article  Google Scholar 

  • Golden Software (2010) Surfer 3D. Golden, Colorado: Golden Software, LLC

  • Holmøy KH (2008) Significance of geologicalparameters for predicting waterleakage in hard rock tunnels

  • Lamas LN, Leitão NS, Esteves C, Plasencia N (2014) First infilling of the Venda Nova II unlined high-pressure tunnel: observed behaviour and numerical modelling. Rock Mech Rock Eng 47:885–904

    Article  Google Scholar 

  • Lipponen A, Manninen S, Niini H, Rönkä E (2005) Effect of water and geological factors on the long-term stability of fracture zones in the Päijänne Tunnel, Finland: a case study. Int J Rock Mech Min Sci 42:3–12

    Article  Google Scholar 

  • Marence M (2008) Numerical modelling and design of pressure tunnels. In: Proceedings of the international conference HYDRO, 2008

  • Merritt AH (1999) Geologic and geotechnical considerations for pressure tunnel design. In: Geo-engineering for underground facilities, 1999, ASCE, pp 66–81

  • Naji AM, Emad MZ, Rehman H, Yoo H (2019) Geological and geomechanical heterogeneity in deep hydropower tunnels: a rock burst failure case study. Tunn Undergr Space Technol 84:507–521

    Article  Google Scholar 

  • Panthi KK (2006) Analysis of engineering geological uncertainties related to tunnelling in Himalayan rock mass conditions

  • Panthi KK, Basnet CB (2019) Leakage potential through a shotcrete lined high-pressure headrace tunnel-An analysis on a case from Nepal. In: Rock mechanics for natural resources and infrastructure development

  • ROCSCIENCE (1998) Phase2 User's Guide. Toronto, Ontario, Canada (1998): Rocscience Inc.

  • Rothfuss BD, Bednarz SL, Clarke ES (2010) Water tunnel condition assessment: a comprehensive approach to evaluating reliability. Jacobs Associates

  • Schleiss A (1986) Design of pervious pressure tunnels. Water Power Dam Constr 38:21–26

    Google Scholar 

  • Sharp JC, Gonano LP (1982) Rock engineering aspects of the concrete lined pressure tunnels of the Drakensberg pumped storage scheme. In: ISRM International Symposium, 1982. International Society for Rock Mechanics and Rock Engineering

  • Sinha RS (2012) Underground structures: design and instrumentation. Elsevier, Amsterdam

    Google Scholar 

  • Wang T, Hu W, Wu H, Zhou W, Su K, Cheng L (2018) Seepage analysis of a diversion tunnel with high pressure in different periods: a case study. Eur J Environ Civ Eng 22:386–404

    Article  Google Scholar 

Download references

Acknowledgements

The authors (Abdul Muntaqim Naji and Hafeezur Rehman) are extremely thankful to the Higher Education Commission (HEC) of Pakistan for HRDI-UESTPs scholarship. This work was supported by the National Research Foundation of Korea Grant funded by the Korean Government (NRF-2019R1A2C2003636).

Author information

Authors and Affiliations

  1. Neelum Jhelum Hydropower Project, Islamabad, Pakistan

    Saeed Ahmad & Ijaz Hussain

  2. Department of Civil and Environmental Engineering, Hanyang University, 55 Hanyangdaehak-ro, Sangnok-gu, Ansan, 426-791, Republic of Korea

    Abdul Muntaqim Naji, Hafeezur Rehman & Hankyu Yoo

  3. Department of Geological Engineering, Balochistan University of Information Technology Engineering and Management Sciences (BUITEMS), Quetta, 87300, Pakistan

    Abdul Muntaqim Naji

  4. Department of Mining Engineering, Balochistan University of Information Technology Engineering and Management Sciences (BUITEMS), Quetta, 87300, Pakistan

    Hafeezur Rehman

Authors
  1. Saeed Ahmad
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Abdul Muntaqim Naji
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Ijaz Hussain
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Hafeezur Rehman
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Hankyu Yoo
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Hankyu Yoo.

Ethics declarations

Conflict of interest

The authors declare that they have no conflict of interest.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Ahmad, S., Naji, A.M., Hussain, I. et al. Ground Saturation Response During First Filling of Lined Pressure Tunnels: A Case Study. Rock Mech Rock Eng 54, 513–535 (2021). https://doi.org/10.1007/s00603-020-02296-9

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00603-020-02296-9

Keywords

Search

Navigation