南海北部深水区表层沉积物工程性质的统计特征分析  

Statistical characteristics analyses on engineering properties of surface sediments in the deep-water of northern South China Sea

作　　者：刘剑涛[1] 师玉敏 王俊勤 朱友生 李畅飞 漆文刚[2,3] 高福平 LIU Jiantao;SHI Yumin;WANG Junqin;ZHU Yousheng;LI Changfei;QI Wengang;GAO Fuping(Geophysical Services Division,China Oilfield Services Limited,Tianjin 300459,China;Key Laboratory for Mechanics in Fluid Solid Coupling Systems,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China;School of Engineering Science,University of Chinese Academy of Sciences,Beijing 100049,China;China National Offshore Oil Company(CNOOC)Research Institute,Beijing 100028,China)

机构地区：[1]中海油田服务股份有限公司物探事业部,天津300459 [2]中国科学院力学研究所流固耦合系统力学重点实验室,北京100190 [3]中国科学院大学工程科学学院,北京100049 [4]中海油研究总院有限责任公司,北京100028

出　　处：《海洋工程》2021年第6期90-98,151,共10页The Ocean Engineering

基　　金：国家杰出青年科学基金项目(11825205);中国科学院战略性先导科技专项(B类)(XDB22030000)。

摘　　要：针对从中国南海北部海域某深水区采集的表层沉积物柱状样,进行了沉积物微观结构的扫描电镜测试、矿物成分的X射线衍射试验以及物理和力学性质的统计学分析。结果表明,该深水区海底表层沉积物通常为有机质软黏土,具有高含水率、低密度、高孔隙比、高液限、高可塑性、低强度等典型特征。统计分析和假设检验表明,沉积物的物理和力学指标均呈现变异性,且后者普遍高于前者。相对密度、含水率、液塑限和塑性指数服从正态分布;容重、碳酸盐含量、不排水抗剪强度、灵敏度接近假设检验结果,近似服从正态分布。研究结果可为深水海底工程结构设计的海床土性参数取值提供参考。The microstructure and mineral composition of the samples of surface sediments from a deep-water field in the northern South China Sea are investigated via SEM and XRD;meanwhile,statistical analyses are performed on the physical and mechanical properties of the sediments.It is found that the surface sediments are generally soft organic clay,characterized by high water content,low density,high void ratio,high liquid limit,high plasticity,low strength,etc.Moreover,the properties of such deep-sea sediments exhibit an inherent variability.Statistical analyses and hypothesis testing indicate that the variability of mechanical properties is usually more pronounced than that of physical properties.The specific gravity,natural water content,plastic and liquid limit,and plasticity index basically obey normal distributions,while the unit weight,carbonate content,undrained shear strength and sensitivity match well with hypothesis testing results,approximately following normal distributions.The present results on the statistical features of deep-sea sediments may provide a reference for geotechnical design of subsea structures in deep waters.

关 键 词：深海沉积物 南海北部 微观结构 物理力学特性 统计特征 

分 类 号：P736.2[天文地球—海洋地质]