Skip to main content

Advertisement

SpringerLink
Log in

Excavation unloading destruction phenomena in rock dam foundations

  • Original Paper
  • Published:
Bulletin of Engineering Geology and the Environment Aims and scope Submit manuscript

Abstract

Excavation unloading destruction (EUD) is a common phenomenon in the large-scale construction sites in Southwest China, where intense horizontal tectonic stresses are present in the rock mass. The paper discusses the Xiaowan hydropower dam where stresses of 23–35 MPa were measured in the strata in the valley sides and 44–57 MPa in the floor of the valley. It describes the characteristics of EUD, discussing the laminar, arched and imbricate fractures which occurred when the near surface strata were excavated for the dam construction. The EUD fractures were largely restricted to the upper 6 m below the excavation and were particularly pronounced in the top 2 m. It is concluded that the typical Mohr Coulomb formula is not applicable where a rock mass near its critical stress is rapidly unloaded. A better understanding of EUD is important for the prediction of rock bursts etc. and hence safety in large engineering constructions in highly stressed strata.

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

Similar content being viewed by others

References

  • Blümling P, Frederic B, Patrick L, Martin CD (2007) The excavation damaged zone in clay formations time-dependent behaviour and influence on performance assessment. Phys Chem Earth 32:588–599

    Google Scholar 

  • Bossart P, Trick T, Meier PM, Mayor JC (2004) Structural and hydrogeological characterisation of the excavation-disturbed zone in the Opalinus Clay (Mont Terri Project, Switzerland). Appl Clay Sci 26:429–448

    Article  Google Scholar 

  • Cai M, Kaiser PK (2005) Assessment of excavation damaged zone using a micromechanics model. Tunn Undergr Space Technol 20:301–310

    Article  Google Scholar 

  • Cai M, Kaiser PK, Tasaka Y, Maejima T, Morioka H, Minami M (2004) Generalized crack initiation and crack damage stress thresholds of brittle rock masses near underground excavations. Int J Rock Mech Min Sci 41:833–847

    Google Scholar 

  • Cerrolaza M, Garcia R (1997) Boundary elements and damage mechanics to analyze excavations in rock mass. Eng Anal Boundary Elem 20:1–16

    Article  Google Scholar 

  • Jubien WE, Abbott BC (1989) Landslide stabilized by an unloading excavation. Proc Int Conf Soil Mech Found Eng 3:1569–1572

    Google Scholar 

  • Kalkani EC (1977) Excavation unloading effect in rock wedge stability analysis. Can Geotech J 14:258–262

    Google Scholar 

  • Malmgren L, Saiang D, Toyra J, Bodare A (2007) The excavation disturbed zone (EDZ) at Kiirunavaara mine, Sweden by seismic measurements. J Appl Geophys 61:1–15

    Article  Google Scholar 

  • Sabine K, Ugur Y (2004) Detection and characterization of the disturbed rock zone in claystone with the complex resistivity method. J Appl Geophys 57:63–79

    Article  Google Scholar 

  • Sato T, Kikuchi T, Sugihara K (2000) In situ experiments on an excavation disturbed zone induced by mechanical excavation in Neogene sedimentary rock at Tono mine, central Japan. Eng Geol 56:97–108

    Article  Google Scholar 

  • Schuster K, Alheid HJ, Böddener D (2001) Seismic investigation of the excavation damaged zone in Opalinus Clay. Eng Geol 61:189–197

    Article  Google Scholar 

  • Sheng Q, Yue ZQ, Lee CF, Tham LG, Zhou H (2002) Estimation of the excavation disturbed zone in the permanent shiplock slopes of the Three Gorges Project, China. Int J Rock Mech Min Sci 39:165–184

    Article  Google Scholar 

  • Wu FQ (1993) Principles of statistical mechanics of rock masses. China University of Geosciences Press, Wuhan

    Google Scholar 

  • Wu FQ, Wang SJ (2001) A stress-strain relation for jointed rock masses. In J Rock Mech Min Sci 38:591–598

    Article  Google Scholar 

  • Wu FQ, Liu JY, Liu T, Zhuang HZ, Yan CG (2008) A method for assessment of excavation damaged zone (EDZ) of a rock mass and its application to a dam foundation case. Eng Geol doi: 10.1016/j.enggeo.2008.11.005

  • Xie HO, He CH (2004) Study of the unloading characteristics of a rock mass using the triaxial test and damage mechanics. Int J Rock Mech Min Sci 41:74–80

    Article  Google Scholar 

Download references

Acknowledgments

This research is financially supported by the project “Research on key geological problems related to safety of deep-level and long tunnels (KZCX2-YW-109)” from Chinese Academy of Sciences.

Author information

Authors and Affiliations

  1. Key Lab of Engineering Geomechanics, Institute of Geology and Geophysics, Chinese Academy of Sciences, 100029, Beijing, China

    Faquan Wu, Tong Liu & Jianyou Liu

  2. Kunming Hydropower Investigation and Design Institute, 650051, Kunming, China

    Xianliang Tang

Authors
  1. Faquan Wu
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Tong Liu
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Jianyou Liu
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Xianliang Tang
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Jianyou Liu.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Wu, F., Liu, T., Liu, J. et al. Excavation unloading destruction phenomena in rock dam foundations. Bull Eng Geol Environ 68, 257–262 (2009). https://doi.org/10.1007/s10064-009-0202-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10064-009-0202-5

Keywords

Search

Navigation