Papers by Keyword: Principle of Minimum Energy Dissipation

Abstract: Composite roughness is an important parameter in river hydraulic calculations. In this paper, various typical methods for predicting composite roughness of river were summarized, including Einstein Method, Lotter Method, JIANG Method and Weighted Average Method, their theoretical rigors were discussed from both perspectives of minimum energy dissipation principle and analytical analysis, and their calculation precisions were verified by a large number of flume test data. Research shows that Einstein Method complies with the principle of minimum energy dissipation, also is the necessary and sufficient condition of resistance equation having unique solution, and its calculation precision is higher, therefore, Einstein Method is more suitable for composite resistance calculation of river with single cross section.

Abstract: This paper introduces the principle of minimum energy dissipation and its general procedures to establish development equation of internal variable. With the accepted viewpoint that the damage is only mechanics of energy dissipation during the rockburst and utilizing the total strength criterion based on released strain energy, the general damage evolution equation is deduced. Compared with the traditional research method of damage evolution equation, this method has universal and objective characteristics.