低温环境下南海海底泥流的流变试验及模型  

Rheological tests and model for submarine mud flows in South China Sea under low temperatures

作　　者：郭兴森 年廷凯[1,2,3] 范宁 焦厚滨[1] 贾永刚 GUO Xing-sen;NIAN Ting-kai;FAN Ning;JIAO Hou-bin;JIA Yong-gang(State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China;State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining and Technology,Xuzhou 221008,China;Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering,Ocean University of China,Qingdao 266100,China)

机构地区：[1]大连理工大学海岸和近海工程国家重点实验室,辽宁大连116024 [2]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州221008 [3]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

出　　处：《岩土工程学报》2019年第1期161-167,共7页Chinese Journal of Geotechnical Engineering

基　　金：国家重点研发计划项目(2016YFE0200100;2018YFC0309203);国家自然科学基金项目(51879036;41427803);深部岩土力学与地下工程国家重点实验室基金项目(SKLGDUEK1307);山东省海洋环境地质工程重点实验室基金项目(MEGE1603)

摘　　要：海底泥流是海底斜坡失稳后演化的流态化滑坡体,常对海洋工程设施造成严重破坏,而目前针对这种泥流的流变特性研究较少,特别是考虑海底低温环境。基于南海北部陆坡软黏土原状样制备泥流,采用RST流变仪开展具有不同温度与含水率的泥流流变试验,引入Herschel-Bulkley模型对流变参数进行深入探讨,建立考虑低温效应与含水率变化的海底泥流综合流变模型。进一步,通过相态转化、布朗运动与粒际作用的理论,解释并分析了海底泥流的流变特征及其变化机理。研究表明:与常温条件相比,低温环境下泥流的剪应力与表观黏度显著提高,且随着剪切速率的增加差距变大,平均变化量可超过35%。这一成果可为海底泥流运动过程数值模拟与海底滑坡灾害预测提供科学依据。The submarine mud flow, a fluidized landslide mass developed from the unstable submarine slope, is easy to cause a serious damage to the offshore engineering facilities. At present, there are rarely researches to discuss the rheological properties of this mud flow, particularly lacking of its characteristic studies considering the low temperatures around the seafloor. For this purpose, the mud flow is prepared by using undisturbed soft clay samped from the South China Sea, and many rheological tests under different temperatures and water contents are conducted by the RST rheometer. Then, the Herschel-Bulkley model is introduced to analyze the rheological parameters, and the integrated rheological model for the submarine mud flow is proposed. Further, the rheological characteristics and mechanisms of the submarine mud flow are analyzed by the phase transformation, the Brownian motion and the interparticle interaction. The research results show that the shear stress and apparent viscosity of the mud flow under the low temperatures significantly increase as compared with those under the room temperature, and this change percentage will further rise with the increase of the shear strain rate, and the average value of the change is more than 35%. This study may provide a scientific basis for the numerical simulation of submarine mud flows and the prediction of landslide hazards.

关 键 词：南海 海底泥流 低温流变试验 综合流变模型 流变机理 

分 类 号：TU411[建筑科学—岩土工程]