含水合物砂中静力触探的数值模拟  

Numerical Simulation of Cone Penetration Tests in Hydrate Bearing Sand

作　　者：孔壮壮 申志聪 陈强 李彦龙[2] 孙建业 赵志超 王栋 KONG Zhuangzhuang;SHEN Zhicong;CHEN Qiang;LI Yanlong;SUN Jianye;ZHAO Zhichao;WANG Dong(Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering,Ocean University of China,Qingdao 266100;Key Laboratory of Gas Hydrate,Ministry of Natural Resources,Qingdao Institute of Marine Geology,China Geological Survey,Qingdao 266071)

机构地区：[1]中国海洋大学山东省海洋环境地质工程重点实验室,山东青岛266100 [2]自然资源部天然气水合物重点实验室·中国地质调查局青岛海洋地质研究所,山东青岛266071

出　　处：《土工基础》2022年第3期400-405,共6页Soil Engineering and Foundation

基　　金：青岛海洋地质研究所基金(HD-JJHT-2020-089);中国海洋大学专项基金(841962013)。

摘　　要：我国南海水合物储层的主要类型为粉细砂层,天然气水合物的开发利用需要快速准确地获取储层力学特性。选用有限元软件Abaqus,采用修正摩尔-库伦模型来描述含水合物砂的刚度、强度和变形特性,并通过纯砂的等向压缩试验和含水合物砂的三轴排水剪切试验标定并验证了本构模型参数。采用任意拉格朗日-欧拉格式的大变形有限元方法,模拟了含水合物砂中静力触探的完整过程,并总结出了不同饱和度下含水合物砂中锥尖贯入阻力经验公式。在模拟过程中允许土体和网格具有不同的流动速度,有效避免了贯入过程中锥尖周围土体网格的扭曲,对此类数值模拟的研究提出了有益的建议。The main hydrate storage layer in the South China Sea is fine sand reservoir.To obtain the mechanical properties of the hydrate reservoirs rapidly and accurately is critical to the development and utilization of the nature gas hydrate.A modified Mohr-Coulomb model was introduced to describe the stiffness,strength and deformation characteristics of hydrate sand by using the commercial finite element software ABAQUS.The constitutive mode response was calibrated by the isotropic compression tests in conventional sand samples and the plastic parameters were determined by the drained triaxial test on the hydrate bearing sand samples.A large deformation finite element method in the form of Arbitrary Lagrange-Eulerian was used to simulate the cone penetration tests in the hydrate sand layers.The numerical model allowed the different flow velocity between the soil and the mesh to avoid the element distortion around the cone tip.An empirical equation for the cone tip resistance varied with different saturation was obtained.

关 键 词：天然气水合物 有限元 大变形 静力触探 

分 类 号：TU413[建筑科学—岩土工程]