Numerical simulation method for hydraulic fracture of core wall of rock-fill dam

Abstract

The invention discloses a numerical simulation method for hydraulic fracture of a core wall of a rock-fill dam. The numerical simulation method comprises the following steps of: establishing a double-axis numerical model of a particle discrete element according to a practical stress-strain curve of soil of the core wall obtained from an indoor plane strain test; establishing a core wall framework particle model according to mesomechanics parameters defined by a double-axis test of the particle discrete element; establishing a fluid model by virtue of a continuous medium model, and dispersing a control equation of of the fluid model; and simulating the hydraulic fracture by virtue of the core wall framework particle model and the fluid model. According to the numerical simulation method, on the basis of the mesomechanics parameters obtained from the indoor test, the practical mechanical property of the soil of the core wall is simulated, and the stress boundary condition of the core wall and the practical hydraulic pressure boundary condition of the upstream of the rock-fill dam are applied to conduct numerical simulation, thereby judging whether the hydraulic fracture of the core wall happens or not from a mesomechanics point of view. According to the simulation result, an improvement measure is provided in the aspects of construction or design to avoid the hydraulic fracture of the core wall, so that the numerical simulation method has guiding significance on practical engineering.

Description

technical field [0001] The invention belongs to the technical field of fluid-solid coupling analysis in geotechnical engineering, and is a numerical simulation method for hydraulic splitting of a core wall of a rockfill dam which combines particle discrete elements and a gridless method. Background technique [0002] Among many dam types, earth-rock dam has become the preferred dam type for high dams because of its wide adaptability, local materials, simple construction technology and good seismic performance, and has been widely used in dam construction. . Especially in recent years, with the further deepening of hydropower development in Southwest my country, the number of 200-300m high earth-rock dams under construction or proposed is gradually increasing. However, in the construction of high earth-rockfill dams, core wall rockfill dams are one of the commonly used dam types in earth-rockfill dams, and there are still some important problems to be solved urgently. One o...

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Problems solved by technology

[0003] Although many experts and scholars have studied the occurrence, development process and mechanical mechanism of hydraulic fracturing from a macro perspective through experiments and finite element numerical simulations, they have not yet reached a consensus, such as which one should be used There are still many controversies about the principal stress or which combination of principal stresses is compared with the external water pressure in front of the core wall as the judgment criterion for hydraulic splitting and the location where hydraulic splitting of the core wall often occurs.

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