天然气水合物分解对地层稳定性影响的离心机实验模拟

水合物分解后将引起地层强度的降低,可能造成海床沉陷、滑塌以及海洋结构物基础的破坏。针对该问题,首先以南海浅层粉砂为沉积物骨架,采用生物厌氧发酵技术合成水合物沉积物,然后进行水合物热分解引起地层响应的离心机实验模拟,获得了水合物分解引起地层变形与滑塌的特征以及孔隙压力发展的物理过程,为研究水合物分解引起海床失稳的条件进行了新的尝试。

Centrifuge Experimental Simulation of the Effect of Gas Hydrate Dissociation on the Seabed Stability

Dissociation of gas hydrate may cause the strength decrease in hydrate-bearing sediments and result in seabed sinking, slumping and destruction of marine structure foundation. To study this project, first, selecting silty sand from South China Sea as the skeletons, using biological anaerobic fermentation techniques, hydrate-bearing sediments were synthesized. Then centrifuge experimental simulation was conducted to investigate the seabed responses during and after the dissociation of gas hydrate. Characteristics of evolution of the seabed sinking and slumping and the pore water pressure were obtained. This work is expected to be beneficial to further study of the instability conditions of the seabed and the correspondent prevention methods.