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Title: Measures of Stability for Roofs over Cavities in Rock
Engineered cavities in rock formations are often part of an underground transportation infrastructure. Three measures of roof stability in such cavities are discussed: the stability number, the factor of safety, and the support pressure needed to prevent cavity roof failure in weak rock. The stability number is a dimensionless combination of the rock properties and the size of the cavity when roof failure becomes imminent. While there exists substantial experience in application of the stability number and the factor of safety to soil structures, their use to define the safety of rock structures is intricate. This is because the strength envelope for rocks is a non-linear function of the mean stress. The specific function used in the analysis is the Hoek-Brown failure criterion. The kinematic approach of limit analysis is used, and the results are presented in charts. All measures of stability are strongly dependent on the Geological Strength Index, and, to a lesser degree, on other parameters in the Hoek-Brown failure criterion.  more » « less
Award ID(s):
1901582
PAR ID:
10402309
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Geo-Congress 2022 GSP 336
Page Range / eLocation ID:
629 to 638
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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