Structure And Function Analysis Of Hydrate Dynamic Triaxial Apparatus

Natural gas hydrate is widely used as a new type of energy, with the characteristics of clean and huge reserves. Compared with other energy sources, it can solve the lack of the world’s energy, and does not pollute the environment. But decomposition of gas hydrate in the sediments will bring serious geological disasters and climate problems. In order to overcome these problems, we need to obtain more accurate data of hydrate sediment characteristics, and the utilization of dynamic triaxial apparatus in this field has also no obvious progress, so the design of hydrate dynamic triaxial apparatus to meet the needs of experiment is imminent. Since2000, scientists in the United States, Japan and other countries firstly began to design the triaxial apparatus to measure the mechanical properties of natural gas hydrate, according to the reservoir conditions. Therefore, in this paper, we analyzed the hydrate dynamic triaxial apparatus function and structure design, and the innovation of hydrate dynamic triaxial apparatus has important significance.It’s impossible to measure some parameters in situ, so we need to do hydrate sediments dynamic triaxial test in the lab. And in order to evaluate of the stability of hydrate sediments foundation under dynamic loads, we need to know about the dynamic properties of hydrate sediments, such as dynamic strength of hydrate sediments, liquefaction characteristic and the dynamic stress strain characteristics, etc. In order to correctly understand this property of hydrate sediments, this paper discussed in detail in the second chapter to introduce the function of hydrate dynamic triaxial experiment apparatus, including design, development suggestions and axial load,(water) of confining pressure and pore air pressure and other updates of the system.Hydrates in ocean environment are generally formed under the condition of the temperature above freezing point, so the traditional sample preparation method can’t well simulate the hydrate sediments consolidated state, and can’t restore the submarine gas hydrates formation process. And it will cause the decomposition of part of the hydrates in the process of sample preparation, leading to low saturation of the sample. Therefore, the third chapter of this paper, in order to make the laboratory condition more close to the hydrate formation process of natural environment, we set up hydrate in situ formation device to obtain in situ hydrate sample.Finally, this paper designed the method of in situ formation and decomposition of the hydrate in dynamic triaxial apparatus, and introduced the detail steps and operation. In addition, we introduced the detailed operation and instructions of hydrate dynamic triaxial experiment instrument software. Above all, this paper analyzed the functions of hydrate dynamic triaxial apparatus structure, and we try to combine the original soil mechanics dynamic triaxial apparatus and the hydrate static triaxial apparatus, and to design a hydrate dynamic triaxial experiment instrument to meet the laboratory dynamic triaxial test of hydrate deposits.