Approximate Theoretical Analysis on Excavation Disturbed Zone of a Soft Rock Slope in Suining-Ziyang Expressway Engineering in Southwestern China

Abstract:

A cutting slope model can be simplified as plane strain one, the stress field of cutting slope can be analyzed with elastic wedge body theory. By using strength criterion of slope material (Mohr-Coulomb strength criterion with safety reserve and uniaxial tensile strength criterion), the disturbed zone caused by excavation can be calculated in 3D stress state, so all the disturbed zone after each step of excavation from the top down can be searched out. The main analysis steps for judging disturbed zone are described in the paper, including the methods to calculate the stress state of cutting slope, the unloading value and the scope of disturbed zone after last step of excavation. Finally, an example in Suining-Ziyang expressway engineering is chosen to explain detailedly the analytical process with elastic wedge body theory to determine the disturbed zone.

• Periodical: Advanced Materials Research (Volume 790)
• Pages: 347-352
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.790.347
• Online since: September 2013
• Authors: Xing Song Cao, Ya Yun Hu, Shi Xiong Liu
• Keywords: Excavation Disturbed Zone, Safety Factor, Soft Rock Slope

References

[1] Shen B., Barton N. Disturbed zone around tunnels in jointed rock masses. International Journal of Rock Mechanics and Mining Sciences and Geomechanics Abstracts, Vol. 34 (1997), p.117.

DOI: 10.1016/s1365-1609(97)80037-8

[2] Luke B. A., Stokoe K. H. II, Bay J. A. Seismic measurements to investigate disturbed rock zones. In: Geo-Institute of the ASCE Proceedings of the 1999 3rd National Conference on Geo-engineering for Underground Facilities. Urbana, IL, USA: Geotechnical Special Publication, (1999).

[3] Autio J., Siitari-Kauppi M., Timonen J. Determination of the porosity, permeability and diffusivity of rock in the excavation disturbed zone around full-scale deposition holes using the 14C-PMMA and He-gas methods. In: Proceedings of the 1997 6th International Conference on the Chemistry and Migration Behavior of Actinides and Fission Products in the Geosphere. Sendai, Japan. Journal of Contaminant Hydrology, Vol. 35(1998).

DOI: 10.1016/s0169-7722(98)00112-0

[4] Sato T., Kikuchi T., Sugihara K. In-situ experiments on an excavation disturbed zone induced by mechanical excavation in Neogene sedimentary rock at Tono mine, central Japan. Engineering Geology, Vol. 56(2000), p.97.

DOI: 10.1016/s0013-7952(99)00136-2

[5] Deng Jianhui, Wang Hao, Jiang Qinghui. Monitor of disturbed zone for rock slope by sliding deformeter. Chinese Journal of Rock Mechanics and Engineering, Vol. 21(2002), p.180.

[6] Xia Xilun, Zhou Huoming, Sheng Qian. Excavation loosened zone and mechanical behaviors of rock mass of lock's high slope of TGP. Journal of Yangtze River Scientific Research Institute, Vol. 16(1999), p.1.

[7] Deng Jianhui, Lee C. F., Ge Xiurun. Disturbed zones and displacement back analysis for rock slopes. Chinese Journal of Rock Mechanics and Engineering, Vol. 20(2001), p.171.

[8] Zhang Xueyan. Geotechnical plastic mechanics. China Communications Press, Beijing(1993).

[9] Xiao Shiguo. Analysis on disturbed zone and some stabilizing structures in high rock slope projects. Southwest Jiaotong University Doctor Degree Dissertation, Chengdu, China (2003).