ABOUT A METHOD FOR THE EXPERIMENTAL DETERMINATION OF THE LAW OF HOOKE FOR ANISOTROPIC ROCK MASSES Elysio R. F. Ruggeri1 SUMMARY In many situations, in dimensioning underground structures, the most realistic forecast of the mechanical behaviour of the fractured rock masses should be done using a continuous, homogeneous, anisotropic, linear and elastic model (a CHALE model), as the isotropy could be utopian. However, one of the difficulties lies in the necessary establishment of the Law of Hooke, either for not having reliable information regarding axis and plains of elastic symmetry of the rock mass or for not being able to defend the adoption of determinable elastic constants by means of laboratory trials of body structures. The indirect determination of elastic constants of a rock mass by the measuring “in situ” of stress and strain tensors – core of the proposed method – may be a practical and economically advantageous mean in implanting and developing undertakings. This method supposes that the quoted measures are being done within a “representative volume element” of the rock mass, thus already taking into consideration its families of fractures. In this article, the method is briefly justified. Also, a discussion about some aspects related to its utility and the emergent improvement difficulties, starts. Practical fieldworks, in course, which will serve as base for new studies and communications, are being announced. KEY WORDS: Hooke, rock mass, anisotropy.
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