压实土孔隙结构特性演化的定量分析  

Quantitative Analysis on the Evolution of the Pore Structure Characteristics of Compacted Soils

作　　者：魏小棋 陈盼 邬凯[4] 田慧会 WEI Xiao-qi;CHEN Pan;WU Kai;TIAN Hui-hui(College of Civil and Architecture Engineering,Guilin University of Technology,Guilin 541004,China;State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China;University of Chinese Academy of Sciences,Beijing 100049,China;Sichuan Highway Planning Survey Design and Research Institute Ltd.,Chengdu 610064,China)

机构地区：[1]桂林理工大学土木与建筑工程学院,桂林541004 [2]中国科学院武汉岩土力学研究所,岩土力学与工程国家重点实验室,武汉430071 [3]中国科学院大学,北京100049 [4]四川省公路规划规划勘察设计研究院有限公司,成都610064

出　　处：《科学技术与工程》2021年第20期8607-8613,共7页Science Technology and Engineering

基　　金：国家自然科学基金(41877269,51939011)。

摘　　要：人工压实土被广泛用于土石坝、路基与垃圾填埋场等重要土工构筑物,其工程力学特性的控制与评诂是土工构筑物长期稳定性的关键。压实土工程力学特性控制的主要内因在于制备形成的孔隙结构,而压实土的孔隙结构主要受土体的初始状态影响。开展了粉土与黏土压实孔隙结构影响因素的研究,同时利用低场核磁共振技术对孔隙结构演化进行定量测定。结果表明:初始含水率、干密度对压实土的孔隙大小及分布有重要影响,且这种影响对粉土与黏土并不相同。压实土的优势孔径随初始含水率的增大先增加后减小,同时干密度增大抑制了初始含水率对压实土孔隙结构的影响。研究识别了压实细粒土孔隙结构演化定量表征的关键参数。The artificially compacted soils are widely used to construct the earth-rock dam,subgrade and landfill engineering.The control and assessment on the engineering mechanical behavior of compacted soils are crucial for the long-term stability of the important earthen structures.The pore structure in compacted soils is one of the main controlling factors on the engineering mechanical behavior.Furthermore,the evolution of pore structure in compacted soils is mainly affected by the initial state.The main factors for affecting the compacted pore structure of the silts and clays were studied.Meanwhile,the evolution of pore structure was quantitatively measured by low field nuclear magnetic resonance.The results show the initial water content and dry density have important influence on the pore size and distribution of the compacted soils.However,the influence for the silty and clayey soils is different.The dominant pore sizes in the compacted soils increase at first and then decrease with the increase of initial water content.The effect of initial water content on the pore structure in the soils is restrained by the increase of dry density of the compacted soils.The key parameters are identified to quantificationally characterize the evolution of pore structure in the compacted fine-grained soils.

关 键 词：压实土 核磁共振 孔隙结构 定量表征 优势孔径 

分 类 号：TU431[建筑科学—岩土工程]