黄河水下三角洲液化与未液化粉土的工程地质性质对比研究  

Comparative Study on the Difference of Engineering Geological Characteristics Between Liquefied Silt and Non-liquefied Silt in the Yellow River Delta

作　　者：宋玉鹏 孙永福 杜星 董立峰 焦鹏飞 SONG Yu-peng;SUN Yong-fu;DU Xing;DONG Li-feng;JIAO Peng-fei(First Institute of Oceanography,MNR,Qingdao 266061,China;Laboratory for Marine Geology and Environment,Pilot National Oceanography Laboratory for Marine Science and Technology(Qingdao),Qingdao 266061,China)

机构地区：[1]自然资源部第一海洋研究所,山东青岛266061 [2]青岛海洋科学与技术试点国家实验室海洋地质过程与环境功能实验室,山东青岛266235

出　　处：《海洋科学进展》2019年第1期55-64,共10页Advances in Marine Science

基　　金：海洋公益性行业科研专项--近海海底地质灾害预测评价及防控关键技术研究(201005005);青岛海洋科学与技术国家实验室鳌山科技创新计划项目(2015ASKJ03)

摘　　要：以黄河水下三角洲埕岛海域海底粉土为研究对象,分析液化后重新固结粉土与未发生过液化粉土的工程地质性质差异,从浅地层剖面影像、土体的静力学参数、动力学参数、微结构特征等方面对比论述二者的不同,从而分析液化对粉土工程地质性质的改造作用。研究结果表明,粉土液化后层理结构消失,土体的主要静力学参数及动力学参数均增大,微结构特征表现为面孔隙比、圆形度及分形维数均减小,总体上土体液化固结后工程地质性质提高,若使液化过的粉土再次发生液化,需要更大的外动力条件才能实现。由于液化后粉土层理结构改变,细粒物质析出,颗粒重新排列,形成更加稳定的结构,从而强度随之增大。This study focused on the silt soil in the Yellow River delta, and analyzed the differences in engineering geological properties between liquefied silt and non-liquefied silt. In order to understand the effect of liquefaction on the engineering geological properties of silt, we indicated the the differences in shallow profile images, soil statics parameters, dynamic parameters and microstructure features. We found that the bedding structure of silt disappeared, the main static and dynamic parameters of soil increased,and the microstructural characteristics such as the surface void ratio, roundness and fractal dimension all decreased after liquefaction. The engineering geological properties of silt were improved. And, if the liquefied silt needs to be re-liquefied again, one must exert more external dynamic conditions than before. Due to the change of silt stratification structure after liquefaction, those fine particles are precipitated and then rearranged to form a more stable structure, which will increase the strength of silt.

关 键 词：粉土 液化 微结构 力学参数 工程地质性质 

分 类 号：P736[天文地球—海洋地质]