Logo Ernst und Sohn

Preview

Author(s):     
 
Day, Jennifer J.; Diederichs, Mark S.; Hutchinson, D. Jean
 
Title:     
 
Optimization of structural contact stiffness and strength for discrete simulation of progressive failure of healed structure
 
Abstract:     
 
Geotechnical analysis for underground excavation design in complex tectonic environments requires an increased understanding and more rigorous consideration of the impact of healed or "intrablock" structure, such as veins, on rockmass behaviour. Intrablock structure occurs between blocks of rock defined and bounded by "interblock structure", the network of joints and other fractures conventionally considered in classic rockmass characterization, classification or rockmass property estimation. Discrete simulation of fractures has become a more commonplace model analysis technique for excavations in jointed rockmasses. Here too, however, special attention is required to simulate intrablock structure within the model. In particular, the selection and evolution of stiffness and strength values for the model discontinuity elements must follow a different logic than that adopted for fractures and true joints. A new concept to better represent the behaviour of intrablock structure in explicit numerical models is proposed and tested in this paper by means of finite element method (FEM) analysis and case study data from a 1, 200 m deep drift. This approach changes the stiffness and strength values of failed intrablock structural elements between pre-peak ("primary"), post-peak ("secondary"), and ultimate ("tertiary") states. The FEM models in the tertiary state match 96 % of overbreak patterns along the case drift, versus 80 % in primary state models. These findings suggest that the proposed method is a good option to more accurately model the influence of intrablock structure on rockmass behaviour.
 
Source:     Geomechanics and Tunnelling 8 (2015), No. 5
 
Page/s:     414-420
 
Language of Publication:     English/German



I would like to buy the article

You can download this article for 25 € as a PDF file (2.12 MB).
The PDF file can be read, printed and saved.
Duplication and forwarding to third parties is not allowed.


Please enter your email address now to start the order process.
The link for the download will be sent to the email address stated after the
order process has been completed.

Your email address


I am an online subscriber

As an online subscriber of the journal "Geomechanics and Tunnelling" you can access this article via Wiley Online Library.

I would like to order "Geomechanics and Tunnelling"

This article has been published in the journal "Geomechanics and Tunnelling". If you would like to learn more about the journal, you can order a free sample copy or find out more information on our website.


Prices include VAT and postage. Prices for 2017/2018.
€ Prices apply to Germany only. Subject to alterations, errors excepted.