摘要
利用水饱和法制备含天然气水合物试样,进行等向压缩试验和不排水三轴试验。采用天然气水合物临界状态(MHCS)模型同时预测排水条件和不排水条件下的三轴试验,并进行变动参数分析。不排水条件下,密实纯砂发生应变硬化,而相近密实度的含水合物试样出现应变软化,峰值偏应力随水合物饱和度和围压增大。通过与排水和不排水三轴试验结果的对比,验证了MHCS模型对含水合物粉细砂的适用性与局限。变动参数分析表明:两个关键参数的取值显著影响峰后偏应力的软化过程,但二者的作用均存在相当程度的不确定性。
The samples containing methane hydrate were prepared by water saturation method,then the isotropic compression tests and a series of undrained triaxial tests were carried out.The methane hydrate critical state(MHCS)model was used to describe the triaxial tests under both drained and undrained conditions,and the variable parameters were analyzed.For the undrained triaxial test,the dense pure sand behave strain-hardening,while the sample containing hydrate behave strain-softening with a similar density.As the increase of the hydrate saturation and confining pressure,the peak deviatoric stress of the sample containing hydrate increases.The applicability and limitation of MHCS model for fine sand containing hydrate are verified by comparing with the simulations and experimental results for drained and undrained triaxial tests.By conducting the variable parameter analysis,two key parameters that significantly affect the softening process of post-peak deviatoric stress were found,but the uncertainty for their function was considerable.
作者
赵志超
朱志鹏
王栋
周鸣亮
Zhao Zhichao;Zhu Zhipeng;Wang Dong;Zhou Mingliang(College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China;College of Civil Engineering, Tongji University, Shanghai 200092, China)
出处
《中国海洋大学学报（自然科学版）》
CAS
CSCD
北大核心
2022年第3期124-130,共7页
Periodical of Ocean University of China
基金
中央高校基本业务经费项目(841962013)
国家自然科学基金项目(42025702)资助。
关键词
天然气水合物
粉细砂
三轴试验
水饱和
本构模型
methane hydrate
fine sand
triaxial test
water saturation
constitutive model
作者简介
赵志超(1991—),男,硕士生,E-mail:zhaozhichao@stu.ouc.edu.cn;通讯作者:王栋,E-mail:dongwang@ouc.edu.cn。
