Device and method for testing barrier performance of unsaturated bentonite granular material

Abstract

The invention discloses a device and a method for testing barrier performance of an unsaturated bentonite granular material. The device comprises a sample chamber for storing a soil sample, a thermal characteristic analysis system for measuring the heat conductivity coefficient of the soil sample in the sample chamber, an expansive force testing system for measuring the expansive force of the soil sample in the sample chamber, and a permeability testing system for measuring the permeability coefficient of the soil sample in the sample chamber. According to the invention, the soil sample is placed in the sample chamber provided with permeable stone, and liquid is injected into the soil sample above the permeable stone by using a pressure / volume controller, so that the constant head permeation process of the soil sample can be realized under the condition that the soil sample is not taken out; a thermal probe is inserted into the soil sample in the sample chamber, so that the real-time continuous measurement of the heat conductivity coefficient of the unsaturated bentonite particle material in the hydration process can be realized; and the expansive force generated by the soil sample is transmitted to a stress sensor through a piston, and real-time continuous measurement of the expansive force of the unsaturated bentonite particle material in the hydration process can be achieved.

Description

Technical field [0001] The present invention relates to the field of expansion soil thermally conductive testing devices, and more particularly to test devices and test methods for a barrier properties of unsaturated bentonite particulate material. Background technique [0002] A large number of studies have shown that deep geological disposal is the most scientifically possible way to deal with high-level radioactive nuclear waste. During the operation of the deep geological placement, the unsaturated bentonite particle mixture filling in the handling hole will have long been a long-term multi-field coupling effect such as surrounding rock fissure, nuclear waste fading heat and geological stress, bentonite particulate material Performance (expansion characteristics, permeation characteristics, heat transfer characteristics) will have complex changes, which in turn affect long-term safety of the long-term service performance of the barrier system and the long-term safety of the d...

AI Technical Summary

Problems solved by technology

Existing research on the determination of bentonite expansion force, permeability coefficient and thermal conductivity is usually fragmented. Due to the differences of different test devices, the size of soil samples and the influence of sample preparation methods, it is difficult to achieve the above three performance indicators. Unified description and comprehensive analysis of development law

Images