Variable water level clay dam slope seepage failure occurrence condition test device and method

Abstract

The invention discloses a variable water level clay dam slope seepage failure occurrence condition test device and method. The device comprises a water storage tank, a water pump, a pressure regulating water tank and a test box, and the test box is divided into a closed water storage chamber and a tail observation chamber through a partition plate, the top of the observation chamber is flush withthat of the water storage chamber, and the bottom of the observation chamber is higher than that of the water storage chamber. A water inlet of the water storage chamber is communicated with a water outlet of the pressure regulating water tank through a pipeline, water is supplied and the water pressure is regulated through the pressure regulating water tank, and the height of the pressure regulating water tank is adjustable. A sandy soil layer is laid at the bottom of the water storage chamber according to the set gradient and thickness, a clay covering layer is laid at the top of the sandy soil layer, and osmometer sensors are embedded in different positions of the sandy soil layer and the clay covering layer respectively. A sand gushing outlet and a plurality of drainage holes are formed at the bottom of the observation chamber and are used for observing and judging the seepage failure conditions, and the sand gushing outlet and the drainage hole are communicated with a sand soil layer filled in the water storage chamber.

Description

technical field [0001] The invention belongs to the technical field of water conservancy engineering, and in particular relates to a test device and a test method for the occurrence condition of seepage failure of a variable water level clay dam slope. Background technique [0002] Seepage damage is the main factor for seepage instability of clay anti-seepage bodies (such as clay bedding of earth-rock dams, clay inclined walls, etc.). When the clay anti-seepage body produces a seepage slope that exceeds its seepage stability due to a large water head, it will often cause seepage damage such as piping and contact erosion. Therefore, the permissible seepage slope of the clay anti-seepage body is the main control index. The seepage gradient of clay anti-seepage body under the condition of fixed water head is easy to obtain, but with the global climate change, drought and flood disasters are becoming more frequent, and the water level changes are becoming more and more complicat...

AI Technical Summary

Problems solved by technology

The seepage slope of clay anti-seepage body under the condition of fixed water head is easy to obtain, but with the global climate change, drought and flood disasters are becoming more and more frequent, and the change of water level is becoming more and more complicated

For example, under the conditions of sudden drought and flood, the water level of the clay anti-seepage body in the upstream of the earth-rockfill dam changes rapidly, and the clay anti-seepage body is in an unsteady seepage state, and a large seepage gradient will occur at the inclined wall or bedding; at the same time, The shrinkage cracks caused by the previous drought on the clay body may also deteriorate the anti-seepage performance of the clay, and the cracks may produce hydraulic splitting under the action of high water levels, further aggravating the possibility of seepage slope value and seepage damage

Defects such as changing water levels and early cracks have an adverse effect on the seepage damage of the clay anti-seepage body, which brings greater challenges to the safe operation of the project

[0003] The conventional test device is limited by the test conditions, and cannot simulate the impact conditions such as changing water head and early cracks, and cannot observe and measure the seepage slope of the clay anti-seepage body under the changing environment

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