**Author details**


### **References**


[5] He, H, Dou, L, Fan, J, Du, T, & Sun, X. Deep-hole directional fracturing of thick hard roof for rockburst prevention. Tunnelling and Underground Space Technology, doi: 10.1016/j.tust.(2012). , 32, 34-43.

Hydraulic fracturing can be used for preconditioning of strong roof sequences. When condi‐ tions allow horizontal fractures to be placed from vertical boreholes, the preconditioning can

The work described in this paper was undertaken as part of the overall windblast management project funded by Narrabri Coal Operations. The authors thank Narrabri Coal, CSIRO, and

and S. Pegg3

[1] Van As, A, & Jeffrey, R. G. Caving induced by hydraulic fracturing at Northparkes Mines. In: J Girard, M. Liebman, C. Breeds, and T. Doe (Eds), The Fourth North American Rock Mechanics Symposium. 31 July- 3 August, (2000). Seattle, WA, USA.

[2] Chacon, E, Barrera, V, Jeffrey, R, & Van As, A. Hydraulic fracturing used to precon‐ dition ore and reduce fragment size for block caving. In: A. Karzulovic and M.A. Al‐ faro (Eds), MassMin August, (2004). Santiago, Chile. Instituto de Ingenieros de

[3] Bunger, A, Jeffrey, R, Kear, J, & Zhang, X. Experimental investigation of the interac‐ tion among closely spaced hydraulic fractures. In 45th US Rock Mechanics / Geome‐

[4] Su DWHMcCaffrey JJ., Barletta L., Thomas EP., and Toothman RC. Hydraulic frac‐ turing of sandstone and longwall roof control- implementation and evaluation. In S.S. Peng, C. Mark, and A.W. Khair (Eds), 20th International Conference on Ground

chanics Symposium. June, (2011). San Francisco, CA, USA. ARMA., 26-29.

Control in Mining, August, (2001). Morgantown, W.V., USA., 7-9.

SCT Operations for granting permission to publish these results.

, K. W. Mills2

1 CSIRO Petroleum and Geothermal, Australia

3 Narrabri Coal Operations Pty Ltd, Australia

Rotterdam: A.A. Balkema.

Chile., 2004, 22-25.

be carried out from the surface.

912 Effective and Sustainable Hydraulic Fracturing

**Acknowledgements**

**Author details**

, Z. Chen1

2 SCT Operations Pty Ltd, Australia

R. G. Jeffrey1

**References**


[18] Kear, J, White, J, Bunger, A. P, Jeffrey, R, & Hessami, M. Three dimensional forms of closely-spaced hydraulic fractures, In: A.P. Bunger, J.D. McLennan, and R.G. Jeffrey (Eds), The International Conference for Effective and Sustainable Hydraulic Fractur‐ ing, May, (2013). Brisbane, Australia. InTech: Rijeka, Croatia., 20-22.

**Chapter 46**

**Estimation of the Impact of Mining on Stresses by Actual**

**Hydrofracture Method–A Case Study in a Copper Mine**

To sustain and increase the productivity in a large underground copper mine in India the management of the mine decided to design and develop stopes below the mined out area. For the design of the stopes a detailed stress measurement programme was carried out by hydrofracture method at different depths from the developments available near the pro‐ posed stope. The result indicated a post mining induced high stress tensor with the direction of the maximum compression (maximum principal horizontal stress) rotated 70- 750 from the pre-mining stress tensor and oriented almost transverse to the ore body as against sub parallel to the orebody during pre- mining stage. A 3-D numerical modeling of the mine with pre mining stress tensor as input parameter substantiated the field result at the post mining stage. The generation of post - mining stress helped in understanding the impact of mining on the stress and was used for design and sequencing of the stoping operation for

Knowing the post mining stress condition is always of interest to the mine designer ahead of designing a mining method in the non-mined areas. This knowledge helps them in the design of stopes, mining sequence and rock reinforcement for the extraction of ores economically and safely. Previous work has examined the impact of mining on stresses as revealed by actual

and reproduction in any medium, provided the original work is properly cited.

© 2013 Sengupta et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

© 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution,

**Measurements in Pre and Post Mining Stages by**

Smarajit Sengupta, Dhubburi S. Subrahmanyam,

Rabindra Kumar Sinha and Govinda Shyam

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/56017

the safe and optimum extraction of the ore.

**1. Introduction**

**Abstract**

[19] Bunger, A. P, Zhang, X, & Jeffrey, R. G. Parameters effecting the interaction among closely spaced hydraulic fractures. SPE Journal, (2012). , 17(1), 292-306.
