开采扰动条件下天然气水合物沉积物力学特性试验研究OA

Mining disturbance of natural gas hydrates is prone to induce their decomposition,leading to the deterioration of sediment mechanical properties and subsequent geological hazards,making relevant research of great engineering value.Taking marine argillaceous silt-type natural gas hydrate-bearing sediments as the research object,a self-developed low-temperature and high-pressure triaxial test device was adopted to conduct indoor shear tests under different cementation states,clay contents and temperatures,so as to explore the influence of each factor on the mechanical properties of sediments after decomposition.The results show that clay content,temperature and cementation state significantly affect the mechanical properties of sediments:uncemented samples with low clay content and low temperature have higher final strength,while cemented samples exhibit stronger deformation resistance;the increase of clay content and temperature will weaken the bearing capacity of sediments.This study clarifies the coupling law of multiple factors and provides a scientific basis for reservoir stability regulation and geological hazard prevention in natural gas hydrate exploitation projects.