Mechanical Characteristics Of Bentonite In Artificial Barrier Structure

Nuclear technology has a wide range of uses in the defense、energy、medicine andso on. A large number of high-level radioactive nuclear waste is generated in theapplication process. Handling of highly radioactive nuclear waste is a problem thatmust be addressed in the process of the development of nuclear technology. As thebentonite has many advantages, it is selected as the buffer material in the deepgeological disposal method. In order to research the distribution of the mechanicalstate in the process of the water absorption when it is used in handle nuclear waste, anew method is proposed. Three-dimensional model and two-dimensional model fora nuclear test tank are built.The main work and important conclusion of this paper are as follows:1.In order to research the distribution of the mechanical state in the process of thewater absorption, a new method of combining the seepage analysis and themechanical calculation was proposed. Build a axisymmetric model for a test device,and carry out the anlasys of it by ABAQUS by using the new method. Compare thecalculation results and experimental measurement in order to determine the accuracyof this calculation method. The result showed that: The calculation results agreed wellwith experimental measurement. Draw conclusion based on the comparison: It isfeasible to carry out mechanical calculations considering the distribution of saturation.2.Build three-dimensional model for a artificial barrier structure and carry out theanlasys of it by ABAQUS by using the new method. Get the relationship betweenstress, the dry density, displacement, the safety rate and the saturation distribution inthe low water-permeable layer based on the result. An coclusion is proved that it isnecessary to consider the impact of the saturation in the process of mechanicalcalculations.3.Build two-dimensional model for a artificial barrier structure and carry out theanlasys of the bentonite by ABAQUS on the condition that the water pressure is0.6Mpa,0.8Mpa,1.0Mpa,1.2Mpa. Get the relationship between stress, the drydensity, displacement, the safety rate and the time and injection pressure in the lowwater-permeable layer based on the result.