Advertisement

Behaviors of Wall and Ground due to T-shaped Excavation

  • Xiaodong ZhaoEmail author
  • Guoqing Zhou
  • Laijun Qiao
  • Yangguang Chen
Geotechnical Engineering
  • 12 Downloads

Abstract

Extensive monitoring was performed on a T-shaped site with a length of 280 m, a width of 16 m, and a maximal depth of 20.4 m. The braced excavation was performed under retaining comprised of cast-in-situ bored piles and jet grouting piles. The field databased wall performance and its influences to ground were assessed by detailed comparisons with that in other excavations. It is showed that the wall deflections, ground movements and bracing forces all exhibited a typical camelback-shaped characteristic along the length direction, and a maximum 100% reduction of which was observed due to the jet grouting. The rebar near sections with varied excavation depths was in a tension state both on the excavation and the retained sides due to the two-dimensional unbalanced force, and the corresponding bracing force was small. The maximum wall deflection δhm decreased as the partitioning excavation moved horizontally, and it was less than 0.04% of the final horizontal excavation length Le. The normalized Fσmax approximately approached to be identical with the normalized Fbmax, while most of the occurring depths for Fσmax were greater than that for Fbmax.

Keywords

T-shaped excavation large length-width ratio varied excavation depth jet grouting wall and ground behaviors 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Borges, J. L. and Guerra, G. T. (2014). “Cylindrical excavations in clayey soils retained by jet grout walls: Numerical analysis and parametric study considering the influence of consolidation.” Computers and Geotechnics, vol. 55, no. 1, pp. 42–56, DOI: 10.1016/j.compgeo.2013.07.008.CrossRefGoogle Scholar
  2. Fearnhead, N., Standing, J. R., Maniscalco, K., and Wan, M. S. (2014). “Deep excavations: Monitoring mechanisms of ground displacement.” Geotechnical Engineering, Vol. 67, No. GE2, pp. 117–129, DOI: 10.1680/geng.13.00047.Google Scholar
  3. Goh, A. T. C. (2017). “Deterministic and reliability assessment of basal heave stability for braced excavations with jet grout base slab.” Engineering Geology, vol. 218, pp. 63–69, DOI: 10.1016/j.enggeo. 2016.12.017.CrossRefGoogle Scholar
  4. Hashash, Y. M. A., Osouli, A., and Marulanda, C. (2008). “Central artery/tunnel project excavation induced ground deformations.” Journal of Geotechnical and Geoenvironmental Engineering, vol. 134, no. 9, pp. 1399–1406, DOI: 10.1061/(ASCE)1090-0241(2008) 134:9(1399).CrossRefGoogle Scholar
  5. Hsieh, H. S., Wang, C. C., and Ou, C. Y. (2003). “Use of jet grouting to limit diaphragm wall displacement of a deep excavation.” Journal of Geotechnical and Geoenvironmental Engineering, vol. 129, no. 2, pp. 146–157, DOI: 10.1061/(ASCE)1090-0241(2003)129:2(146).CrossRefGoogle Scholar
  6. Hsiung, B. C. B., Yang, K. H., Aila, W., and Ge, L. (2018). “Evaluation of the wall deflections of a deep excavation in Central Jakarta using three-dimensional modeling.” Tunneling and Underground Space Technology, vol. 72, pp. 84–96. DOI: 10.1016/j.tust.2017.11.013.CrossRefGoogle Scholar
  7. Li, S., Zhang, D. L., Fang, Q., and Li, Z. J. (2012). “Research on characteristics of retaining wall deformation due to deep excavation in Beijing.” Chinese Journal of Rock Mechanics and Engineering, vol. 31, no. 11, pp. 2344–2353 (In Chinese), DOI: 10.3969/j.issn.1000-6915.2012.11.024.Google Scholar
  8. Liao, S. M., Wei, S. F., Tan, Y., and Liu, J. X. (2015). “Field performance of large-scale deep excavations in Suzhou.” Chinese Journal of Geotechnical Engineering, vol. 37, no. 3, pp. 459–469 (In Chinese) DOI: 10.11779/CJGE201503009.Google Scholar
  9. Osman, A. S. and Bolton, M. D. (2006). “Design of braced excavations to limit ground movements.” Geotechnical Engineering, Vol. 159, No. GE3, pp. 167–175, DOI: 10.1680/geng.2006.159.3.167.Google Scholar
  10. Ou, C. Y., Hsieh, P. G., and Lin, Y. L. (2011). “Performance of excavations with cross walls.” Journal of Geotechnical and Geoenvironmental Engineering, vol. 137, no. 1, pp. 94–104.CrossRefGoogle Scholar
  11. Peck, R. B. (1969). “Deep excavation and tunneling in soft ground. State-of the-art-report.” Proc., 7th Int. Conf. of Soil Mechanics and Foundation Engineering, International Society of Soil Mechanics and Geotechnical Engineering (ISSMGE), Mexico City, Mexico, pp. 225–281.Google Scholar
  12. Qu, C. Y., Liao, J. T., and Cheng, W. L. (2000). “Building response and ground movements induced by a deep excavation.” Geotechnique, vol. 50, no. 3, pp. 209–220, DOI: 10.1680/geot.2000.50.3.209.CrossRefGoogle Scholar
  13. Shi, J. W., Liu, G. B., Huang, P., and Ng, C. W. W. (2015). “Interaction between a large-scale triangular excavation and adjacent structures in Shanghai soft clay.” Tunneling and Underground Space Technology, vol. 50, pp. 282–295, DOI: 10.1016/j.tust.2015.07.013.CrossRefGoogle Scholar
  14. Tan, Y. and Wang, D. L. (2013a). “Characteristics of a large-scale deep foundation pit excavated by the central-island technique in Shanghai soft clay. I: Bottom-up construction of the central cylindrical shaft.” Journal of Geotechnical Geoenvironmental Engineering, vol. 139, no. 11, pp. 1894–1910, DOI: 10.1061/(ASCE)GT.1943-5606.0000928CrossRefGoogle Scholar
  15. Tan, Y. and Wang, D. L. (2013b). “Characteristics of a large-scale deep foundation pit excavated by the central-island technique in Shanghai soft clay. II: Top-down construction of the peripheral rectangular pit.” Journal of Geotechnical Geoenvironmental Engineering, vol. 139, no. 11, pp. 1894–1910, DOI: 10.1061/(ASCE)GT.1943-5606.0000929.CrossRefGoogle Scholar
  16. Tan, Y. and Wang, D. L. (2015). “Structural behaviors of large underground earth retaining systems in Shanghai. I: Un-propped circular diaphragm wall.” Journal of Performance of Constructed Facilities, vol. 29, no. 2, pp. 04014058–1-14, DOI: 10.1061/(ASCE)CF.1943-5509.0000521.CrossRefGoogle Scholar
  17. Tan, Y. and Wei, B. (2012). “Observed behaviors of a long and deep excavation constructed by cut-and-cover technique in Shanghai soft clay.” Journal of Geotechnical and Geoenvironmental Engineering, vol. 138, no. 1, pp. 69–88, DOI: 10.1061/(ASCE)GT.1943-5606. 0000553.CrossRefGoogle Scholar
  18. Wang, Z.W., Ng, C. W. W., and Liu, G. B. (2005). “Characteristics of wall deflections and ground surface settlements in Shanghai.” Canadian Geotechnical Journal, vol. 42, no. 5, pp. 1243–1254, DOI: 10.1016/j.tust.2012.12.008.CrossRefGoogle Scholar
  19. Wu, S. H., Ching, J. Y., and Ou, C. Y. (2013). “Predicting wall displacements for excavations with cross walls in soft clay.” Journal of Geotechnical and Geoenvironmental Engineering, vol. 139, no. 6, pp. 914–927, DOI: 10.1061/(ASCE)GT.1943-5606.0000826.CrossRefGoogle Scholar
  20. Xu, Z. H. (2007). “Deformation behavior of deep excavations supported by permanent structures in Shanghai soft deposit.” PhD Thesis, Shanghai Jiao Tong University, Shanghai, China (In Chinese).Google Scholar

Copyright information

© Korean Society of Civil Engineers and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Xiaodong Zhao
    • 1
    Email author
  • Guoqing Zhou
    • 1
  • Laijun Qiao
    • 2
  • Yangguang Chen
    • 3
  1. 1.State Key Laboratory for Geomechanics and Deep Underground EngineeringChina University of Mining and TechnologyXuzhou, JiangsuChina
  2. 2.Pingdingshan Coal Preparation Design and Research InstituteBeijing Huayu Engineering Co., Ltd.BeijingChina
  3. 3.Dept. of Infrastructure BusinessChina State Construction Engineering Co., Ltd.BeijingChina

Personalised recommendations