ABSTRACT
In order to identify the initial stresses of the ground around a tunnel, a simple method has been proposed. The method is advantageous in that the strain ratio among the convergence data measured at the cross section of the tunnel is not sensitive to the modulus of elasticity of the ground. The strain ratio analyzed by a three-dimensional analysis is linked together with that of the field measurements. Then, the initial stresses are estimated from this relation. As the analytical strain ratio can be prepared in advance of the tunnel construction, the initial stresses can be identified immediately without conducting other computer analyses at the site. Applicability and simplicity support this method.
