摘要
水合物沉积物力学特性研究是天然气水合物开采领域中的热点问题。为深入了解水合物对沉积物力学特性的影响,在提出一个新的水合物沉积物离散元数值试样制备方法的基础上,模拟了不同水合物饱和度沉积物试样的三轴排水试验,并从其应力-应变关系、体变特性、弹性模量及峰值强度等方面对模拟结果及已有室内三轴试验结果进行了对比,然后利用该方法对具有不同微观胶结参数的水合物沉积物样进行了三轴离散元数值试验。研究结果表明:所提出的离散元模拟方法能较好地反映水合物沉积物的主要力学特性;天然气水合物与土颗粒间胶结性能的改变会对水合物沉积物的力学响应产生一定的影响;水合物沉积物强度和模量的增加是孔隙填充水合物和粒间胶结水合物共同作用的结果。
The mechanical behavior of methane hydrate-bearing sediments has been a research focus in the area of exploiting methane hydrate from deep seabed currently. This paper presents a numerical analysis of mechanical behavior of hydrate-bearing sediments by using the discrete element method（DEM）. Firstly, a new method for preparing hydrate-bearing samples in the DEM simulation is proposed. Then, a series of numerical simulations of drained triaxial tests are performed on hydrate-bearing sediments with different hydrate saturations. And the simulation results are compared with the test results obtained in the laboratories. Finally, some numerical experiments on hydrate-bearing sediments with different micro-bond parameters are performed using the same method. The study shows that the DEM simulation is able to capture the main mechanical characteristics of hydrate-bearing sediments; and their mechanical properties will change with the variation of the properties of the bond between methane hydrate and soil particles. Furthermore, it is found that both of their peak strength and elastic modulus are enhanced by the presence of methane hydrate in hydrate-bearing sediments with the forms of cementation and pore-filling in combination.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2014年第1期255-262,共8页
Rock and Soil Mechanics
关键词
水合物沉积物
力学性质
离散元法
三轴排水试验
methane hydrate-bearing sediments
mechanical behavior
discrete element method
drained triaxial test
