Stability of dam slopes of phosphogypsum sludge collectors

Abstract

The results of calculations of the enclosing dam stability of phosphogypsum sludge collectors are presented in the paper. The stability calculations were carried out according to the “RUZO” program; they are based on the method of circular-cylindrical sliding surfaces under the action of basic and seismic loads. The main objective of this work is to determine the minimum safety factors for dam slopes of a given transverse profile under known loads and characteristics of the dam body material. To develop a rational profile of collector dams, 9 options of design models of the structure and its base were considered. The body of the enclosing dams of collectors of considered options consists, as a rule, of two elements: the primary floodwall built of earth materials, and secondary dams constructed according to a different build-up schemes from stored materials. Secondary dams are constructed from stored phosphogypsum by the method of layer-by-layer filling and compaction. The calculations showed that in all considered schemes the minimum safety factors under the action of basic and seismic loads are higher than the standard values. The maximum permissible values of the slopes are established with an allowable margin of safety, thus, the stability of dam slopes in all considered options of the phosphogypsum collector is ensured under basic and special combinations of loads.

Flow calculations in intake structures of hydropower plants

“…The dynamic effect of the flow on the particle of the bottom soil determines the separation of the particle from the system of surrounding particles and its weighing by the flow. Currently, it is believed that the action of the following forces determines the weighing of particles of bottom soil [19][20][21][22][23][24][25][26][27][28][29][30]:…”

“…4. The developed method for calculating the flow paths of pumps based on applying the formulated methods of applying the theory of hydrodynamics makes it possible to design PS and HES with optimal characteristics [20,21]. The method allows for the modernization of the flow parts of hydrounits of various types and different parameters.…”

Methods for calculating the balance during the period of draw-off, drainage of sludge collector cells and construction of secondary embankment dams

“…The total amount of free water in the thickness of phosphogypsum of 6.0 m and the area of S 2 = 399087 m 2 is determined by the formula (31) V св = 399087 • 0.04 • 6 = 95781 m 3 The duration of the discharge of the 2nd cell of the sludge collector under the action of "n" drainage belts is determined by the following ratio (32): From the results obtained, the most optimal value is t os with 7 drainage pipes. For a belt drain made in the form of a banquette from filtering material, the drainage water flow rate during the drainage period is determined by the dependencies ( 20) and ( 33) Q l =45 m 3 ; 4Q l =135 m 3 , 7Q l =270 м 3 Calculations for building up secondary (tiered) dams. Dam of the 1st tier.…”

“…Consequently, production waste generated at chemical plants is stored in various types of storage tanks. At present, the most promising method of removing and storing phosphogypsum is hydrostorage [3][4][5][6][7][8][9]. This storage method provides for the supply of waste in the form of pulp into the hydraulic dump cells, their sequential dehydration in the dump, and the subsequent development of a part of the stored waste for the construction of secondary dams.…”