Rock-soil material penetration deformation testing method under complex stress state and test device

Abstract

The invention discloses a rock-soil material penetration deformation testing method under complex stress state and test device. The test method comprises those steps as follows: fabricate the cylindrical sample, measure and record the sample size; consequently, the sample is placed inside the pressure chamber which is fully closed, and the confining pressure is loaded up to the target value and kept the same controlled by servo. Afterwards, the servo controls the multi-stage osmotic loading pressure and record the water flow volume, axial deformation and circumferential deformation of sample when the osmosis passes through the sample with times so as to determine the changes on osmotic coefficient, axial strain and the circumferential strain of sample, which reflects the osmosis deformation status of sample. It is repeated that the confining pressure and osmosis pressure are loaded which is controlled by servo to achieve the osmosis deformation status of rock-soil material under complex stress state. The test device comprises pressure chamber, confining pressure servo loading system and osmotic pressure servo loading system. The sample is fixed inside the pressure chamber and arranged with an axial strain gauge. The upper part, the middle part and the lower part of the sample are respectively provided with a circumferential strain gauge.

Description

technical field [0001] The invention relates to a test method and a test device for seepage deformation of rock and soil materials under a complex stress state, belonging to the field of rock and soil engineering. Background technique [0002] The seepage and deformation characteristics of rock and soil materials are one of the key issues in the fields of civil engineering, water conservancy and hydropower engineering, and energy engineering. At the same time, the occurrence of seepage deformation engineering accidents, such as slope deformation under the action of groundwater, or even landslides, seepage deformation of earth-rockfill dams and rockfill dams under the action of high water head of reservoir water, rock mass structural surface under long-term reservoir water level and groundwater Under the action, the formation of high seepage pressure leads to instability and failure of the rock mass of the dam foundation or the bank slope of the reservoir. [0003] The seepa...

AI Technical Summary

Problems solved by technology

At present, the existing rock and soil penetration deformation instruments are generally small in scale, and the samples cannot accurately describe the internal structure of rock and soil materials; the stress state is single, and the rock and soil permeability characteristics under complex stress states cannot be tested; the deformation measurement is not accurate enough or cannot Deformation and other deficiencies

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