Study on Thermo-Hydro-Mechanical Coupling Behaviors of Buffer Material

2018 ◽  
pp. 367-375
Author(s):  
Shengfei Cao ◽  
Yuemiao Liu ◽  
Jingli Xie ◽  
Like Ma
Keyword(s):  
Mechanical Coupling ◽  
Buffer Material

Experimental study on the thermo- and hydro- properties of two bentonites as buffer materials

2020 ◽  
Author(s):  
Wei-Hsing Huang
Keyword(s):  
Heat Transfer ◽  
Characteristic Curve ◽  
Swelling Pressure ◽  
Moisture Distribution ◽  
Experimental Program ◽  
Heat Transfer Characteristics ◽  
Geological Disposal ◽  
Mechanical Coupling ◽  
Buffer Material ◽  
High Level

<p>This study aims at investigating the hydraulic and thermal properties which are important for buffer materials to be used for geological disposal of high-level radioactive wastes. MX-80 bentonite and Kunigel V1 bentonite, originated from Wyoming USA and Japan, respectively, were used in the experimental program. The characteristics of these 2 bentonites, including soil-water characteristic curve, swelling pressure, hydraulic conductivity, and thermal conductivity were determined in the laboratory. And these data are applied in the simulation of the resaturation processes of buffer material in a deposition hole, such that a comparison can be made on the thermo-hydro-mechanical coupling effects of the buffer material can be evaluated. It is found that the two bentonites do not behave very differently in terms of the moisture distribution and heat transfer characteristics with the same boundary conditions assumed. </p>

scholarly journals The Healing Process of the Joints between Buffer Material Blocks and the Influence on Solute Migration

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Rui Zhou ◽  
Yuemiao Liu ◽  
Tao Xu ◽  
Yufeng Gao
Keyword(s):  
Diffusion Coefficient ◽  
Healing Process ◽  
Design Parameters ◽  
Dry Density ◽  
Mechanical Coupling ◽  
Water Head ◽  
Bentonite Buffer ◽  
Buffer Material ◽  
External Water ◽  
And Diffusion

A set of thermo-hydro-mechanical coupling control equations was established, and the healing process of the joints between Gaomiaozi bentonite (GMZ01) buffer material blocks and the influence of the joint parameters were numerically simulated. The calculations consider the effect of joints on solute migration, the permeability and thermal conductivity of the buffer material, and the evolution of the healing effect. The effects of the joint design parameters, including the type, number, width, splicing form, and average dry density of the joint, are investigated. Studies show that, under an external water head, the joints will become hydraulic priority channels due to their higher permeability, which will shorten the saturation time of the blocks. As the bentonite gradually saturates, the swelling force compresses the joint material. This action improves the overall uniformity of the buffer material and reduces the priority channel effect. Meanwhile, the final average permeability and diffusion coefficient of the buffer material are found to mainly depend on the average dry density of the buffer material. The higher the average dry density of the buffer material is, the lower the final average permeability and diffusion coefficient are, whereas the distribution of joints and the block splicing are less affected by the average dry density of the buffer material. The findings of this study can provide a reference for the design of bentonite buffer material blocks in the repository.

A two degrees of freedom comb capacitive-type accelerometer with low cross-axis sensitivity

2019 ◽  
Vol 13 (3) ◽  
pp. 5334-5346
Author(s):  
M. N. Nguyen ◽  
L. Q. Nguyen ◽  
H. M. Chu ◽  
H. N. Vu
Keyword(s):  
Degrees Of Freedom ◽  
Proof Mass ◽  
Vibration Modes ◽  
Electrode Structure ◽  
Element Analysis ◽  
Mechanical Coupling ◽  
Fully Differential ◽  
Mode Effects ◽  
The Finite Element Analysis ◽  
Cross Axis

In this paper, we report on a SOI-based comb capacitive-type accelerometer that senses acceleration in two lateral directions. The structure of the accelerometer was designed using a proof mass connected by four folded-beam springs, which are compliant to inertial displacement causing by attached acceleration in the two lateral directions. At the same time, the folded-beam springs enabled to suppress cross-talk causing by mechanical coupling from parasitic vibration modes. The differential capacitor sense structure was employed to eliminate common mode effects. The design of gap between comb fingers was also analyzed to find an optimally sensing comb electrode structure. The design of the accelerometer was carried out using the finite element analysis. The fabrication of the device was based on SOI-micromachining. The characteristics of the accelerometer have been investigated by a fully differential capacitive bridge interface using a sub-fF switched-capacitor integrator circuit. The sensitivities of the accelerometer in the two lateral directions were determined to be 6 and 5.5 fF/g, respectively. The cross-axis sensitivities of the accelerometer were less than 5%, which shows that the accelerometer can be used for measuring precisely acceleration in the two lateral directions. The accelerometer operates linearly in the range of investigated acceleration from 0 to 4g. The proposed accelerometer is expected for low-g applications.

Failure in rocks. Hydro-mechanical coupling for erosion

2004 ◽  
Vol 8 (5-6) ◽  
pp. 709-734 ◽  
Author(s):  
Euripides Papamichos
Keyword(s):  
Mechanical Coupling

Research of operation safety and maneuverability of agricultural low-tonnage road train under critical traffic conditions

2020 ◽  
pp. 28-37
Author(s):  
Zakhid A. Godzhayev ◽  
Teymur Z. Godzhayev ◽  
Vladimir A. Korolyash ◽  
Ol’ga Yu. Solov’yeva
Keyword(s):  
Load Capacity ◽  
Research Purpose ◽  
State Technical ◽  
Safe Operation ◽  
Mechanical Coupling ◽  
Emergency Braking ◽  
Traffic Conditions ◽  
Critical Traffic ◽  
Difficult Road ◽  
Agricultural Machines

The article considers conditions for safe operation of low-tonnage road trains with overall trailers, namely universal platforms with a load capacity of up to 3 tons, capable of transporting agricultural machines, mini-factories and other equipment, as well as tourist houses. Transportation of such trailers on wheels is associated with high risks arising at small turning radii and emergency braking. (Research purpose) The research purpose is in improving the safety of operation and maneuverability of agricultural low-tonnage road trains operating in difficult road and terrain conditions of agricultural production. (Materials and methods) Authors have analyzed the results of research and experiments on the safe operation of low-tonnage road trains with trailers weighing up to 1 ton. The authors developed and tested on the basis of VIM and the Volga State Technical University a mechanical coupling device with a flexible connection that increases the handling and maneuverability of the trailer. (Results and discussion) The authors determined that the critical turning radii depending on the speed of a low-tonnage road train in different road conditions and different loading of the trailer when driving in front and rear for a conventional single-axle trailer with a load capacity of 1.5; 2; 2.5; 3 tons. It was found that the maneuverability is largely provided by the additional force in the cable, so authors recommend using a cable with a diameter of at least 9 mm. (Conclusion) Further research will make it possible to determine the critical indicators of safe operation of a low-tonnage road train with a load capacity of up to 3.5 tons: safe speed when passing critical turns, emergency braking and reversing.

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