Conference Proceedings
14th Australasian Tunnelling Conference
Conference Proceedings
14th Australasian Tunnelling Conference
Analytical Approach for Stability Analysis of Rock Wedges with Soil-Infilled Joints Formed in a Tunnel Roo
The use of an equivalent continuum for a rock mass is not always suitable for situations where the failure is structurally controlled by discontinuities as in the case of wedges in the tunnel roof. In these instances, discontinuum approaches are usually preferred. Rock joints that are filled with soft infill are likely to be the weakest planes in a rock mass, having a dominant influence on its overall shear behaviour. In this case, the joint material model adopted for the discontinuities should be able to describe important mechanisms, such as asperity sliding and shearing, post-peak behaviour, asperity deformation, and the effect of the soft infilling. The latest version of a soil-infilled joint model is discussed here. It describes more comprehensively than previous models the occurrence of dilation and compression with lateral displacements, and also represents the hardening mechanism related to asperity interference as observed in the laboratory that cannot be readily captured by the existing joint models. An analytical approach for the analysis of rock wedges structurally controlled by soil infilled joints is presented.The analytical approach presented in this paper for assessment of symmetric rock wedges in the roof of a tunnel demonstrates, that the peak shear strength of the joint may not be fully mobilised before detachment of the wedge. The analysis verifi ed that an overestimation of the factor of safety may be observed when an elastic-perfectly-plastic joint model was assumed, whereas the computed maximum factor of safety was considerably less when adopting an appropriate soil-infilled joint model.
Contributor(s):
D Oliveira, B Indraratna
-
Analytical Approach for Stability Analysis of Rock Wedges with Soil-Infilled Joints Formed in a Tunnel RooPDFThis product is exclusive to Digital library subscription
-
Analytical Approach for Stability Analysis of Rock Wedges with Soil-Infilled Joints Formed in a Tunnel RooPDFNormal price $22.00Member price from $0.00
Fees above are GST inclusive
PD Hours
Approved activity
- Published: 2011
- PDF Size: 0.3 Mb.
- Unique ID: P201102037