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The massive rock slope is made up of rocks and structural surface. The existence and strength of the structural surface decides the stability of the rock mass. By adopting the lower bound method for the plastic limit analysis of wedge slope, we can easily calculate the stability of the rocky slope under various circumstances. To apply this method, we first took the wedge-shaped slide block as a complex of rigid block and structural surface for the analysis of the slope stress under the function of anchor bolts, the integrated function of rocks and structural surfaces being considered. Then, on the basis of the lower bound theory for the plastic limit analysis, a mathematical programming model which takes safety factor of slope stability as the object function is established. This model has to meet the equilibrium condition of the bolt, the Mohr-Coulomb yield condition and the boundary condition of slope. In the end, a classic model of wedge is analyzed and its lower bound solution is worked out. This result is compared to the result worked out by limiting equilibrium to test the validity of the measure and procedure used in this paper.

Based on the Reynolds averaged Navier-Stokes equations, numerical simulation of unsteady flows in the flow passage in spiral case of a hydro-turbine was conducted. The computational domain of the flow passage includes spiral case, stay vanes and guide vanes. The RNG turbulence model in curvilinear body-fitted coordinate systems with finite volume algorithm is adopted. Numerical calculations are conducted under the boundary condition with operating regime for current guide vane openings. And pressure distribution and velocity distribution within the flow path are obtained. The results are helpful to improve the comprehensive hydraulic performances and to enhance the operating stability of a machinery set.

Based on the strong interaction method that combines FEM with acoustic theory, the finite element dynamic equations of spiral casing structure are built, which provides the basis for analyzing self-olsillatin characteristics of spiral casing structure. The self-olsillatin characteristics of structure are calculated with the method. The natural vibration frequencies, and mode shapes are obtained.