1969 年 85 巻 975 号 p. 483-490
Analytical consideration of rock pressure has been conducted by using several mechanical models which are first approximations to the behaviour of rock substances underground.
In this report, states of stress and strain around the round and horizontal tunnelwhich is excavated in the infinite body under hydro-static pressure, are discussed to the following five cases:
(1) Rock is pure elastic.
(2) Rock is represented by a combination of Maxwell's body for the deviatovic partand Hookean body for the invariant part of the stress and strain relation.
(3) In the 2nd model, Kelvin model is existed instead of the Hooke body and Burgers body is existed instead of the Maxwell body.
(4) Rock is pure elastic until the maximum difference of the principal stresses reaches a finite value, and after that, the behaviour of the state of stress and strain is followed with the formula |σγγ-σθθ|=k.
(5) Rook is pure elastic and plastic and the state of stress is followed with the formulaτ=C+σ tanψin the plastic region.