WATER RESERVOIR LOADING OF LONG ANISOTROPIC VALLEYS WITH IRREGULAR TOPOGRAPHIES

The nature of the stress field induced by water reservoir lending of l ong anisotropic valleys is considered using an analytical method propo sed earlier by the authors. The rock mass is modeled as a linearly ela stic, transversely isotropic or nearly isotropic and homogeneous conti nuum that deforms under a condition of plane strain. The method is use d to determine stresses in symmetric and asymmetric valleys induced by water reservoir loaning with or without gravity. Numerical examples a re presented to analyze the disturbance associated with a water reserv oir on the existing gravitational stress field. They show that the pre sence of a water reservoir does not much affect the horizontal and ver tical gravity-induced normal stresses except near the valley bottom. T here the effect of the water reservoir is to reduce the magnitude of t he gravity-induced horizontal tensile stress and to increase the magni tude of the gravity-induced vertical compressive stress. On the other hand water reservoir loading affects the gravity-induced shear stress in a relatively large region below the valley. Finally a parametric st udy is presented on the effect of (1) water reservoir height, (2) degr ee of anisotropy, and (3) orientation of anisotropy on the magnitude a nd distribution of stresses induced by water reservoir loading only. ( C) 1996 by Elsevier Science Inc.