含水量对冻结含盐粉土单轴抗压强度影响的试验研究  

An Experimental Study of Influence of Water Content on Uniaxial Compression Strength of Frozen Salty Silt

作　　者：陈锦[1,2] 李东庆[1] 邴慧[1] 邓友生[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室,甘肃兰州730000 [2]中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室,北京100101

出　　处：《冰川冻土》2012年第2期441-446,共6页Journal of Glaciology and Geocryology

基　　金：国家重点基础研究发展计划(973计划)项目(2012CB026102);国家自然科学基金项目(40901039;40571068)国家自然科学基金创新群体项目(41121061)资助;冻土工程国家重点实验室基金(SKLFSE-ZY-03)

摘　　要：采用取自甘肃省白银市平川区黄河岸边的天然盐渍土,用蒸馏水洗去土中的盐分,配制成NaCl/Na2SO4含量为1.5%,含水量不同的试样,研究了冻结条件下含水量对冻结含盐粉土单轴抗压强度、破坏应变的影响.结果表明:当含水量较小时,随着含水量的增加,冰的胶结作用增强,并与土颗粒、盐晶体一起承受荷载,冻结含盐土的单轴抗压强度不断增大;当含水量超过某一值时,试样更多地呈现出冰的性质,而冰的强度远远小于矿物颗粒的强度,单轴抗压强度随含水量的增加而减小.随着含水量的变化,含盐土的破坏应变与单轴抗压强度有相似的变化规律.In order to find the change law of uniaxial compression strength and failure strain of freezing salty silt under the influence of water content,natural saline soil was collected from the shore side of the Yellow River in Pingchuan district of Baiyin Municipality of Gansu Province as the sample.After leaching with distilled water,the soil was used to prepare specimens containing NaCl/Na2SO4 at salt content of 1.5% with different water contents.Analytically pure sodium sulfate and sodium chloride are used in the test.The test results indicate that when the water content was low,as the water content increasing,cementing power of ice increases,at the same time,ice endure more and more load with soil particles and crystals of salt,so the uniaxial compression strength of frozen salty soil will increase.When the water content increases to a certain degree,ice plays a leading role in the soil,the specimen presents the properties of ice,and the compression strength of ice is far less than that of mineral grains,so the uniaxial compression strength of frozen salty silt will decrease when the water content is over a given value.Failure strain has the similar change law with uniaxial compression strength changing with water content.

关 键 词：含水量 冻土 含盐土 单轴抗压强度 破坏应变 

分 类 号：P642.14[天文地球—工程地质学]