冻融和易溶盐对石灰固化伊犁黄土强度及水稳性的影响  

Effect of Soluble Saltand Freeze-thaw Cycle on Strength Deterioration and Water Stability of Lime-treated Ili Loess

作　　者：梁志超 任文渊[1] 李双村 张爱军[1,2] 王毓国 LIANG Zhichao;REN Wenyuan;LI Shuangcun;ZHANG Aijun;WANG Yuguo(College of Water Resources and Architectural Engineering,Northwest A&F University,Yangling 712100,Shaanxi,China;College of Civil engineering,Xijing University,Xi’an 710000,China;Institute for Interdisciplinary and Innovation Research,Xi’an University of Architecture and Technology,Xi’an 710000,China)

机构地区：[1]西北农林科技大学水利与建筑工程学院,陕西杨凌712100 [2]西京学院土木工程学院,西安710000 [3]西安建筑科技大学交叉创新研究院,西安710000

出　　处：《材料导报》2025年第6期144-151,共8页Materials Reports

基　　金：国家自然科学基金面上项目(51978572)。

摘　　要：冻融作用和易溶盐是诱发寒区输水渠道土体破坏的重要原因。通过无侧限抗压强度试验、崩解试验、渗透试验和核磁共振试验,分析了冻融作用和易溶盐含量对石灰固化伊犁黄土强度、水稳性以及孔隙结构的影响规律及程度。研究结果表明:冻融作用对石灰固化伊犁黄土强度有明显的劣化作用,冻融前期强度劣化严重,且易溶盐含量越高,冻融作用对强度劣化程度越严重。当易溶盐含量高于14 g/kg时,强度衰减趋势减小。冻融循环次数和易溶盐含量的增加会加速石灰固化伊犁黄土的崩解,且易溶盐含量对其水稳性影响较大,当易溶盐含量高于8 g/kg时,试样崩解速率增速明显。渗透性随着冻融循环次数和易溶盐含量增大而增大,且冻融作用比易溶盐含量对渗透性影响更大;当易溶盐含量为26 g/kg时,由于渗透吸力的作用,渗透系数明显减小。冻融作用使得土体孔隙模态尺寸增大,主要影响了中孔隙和大孔隙;易溶盐含量对孔隙结构的影响弱于冻融作用。考虑冻融作用和控制易溶盐含量对寒区土体的强度及水稳性至关重要。Freeze-thaw cycle and soluble salt are main reasons for the damage of soils of water conveyance channels in cold regions.To explore the in-fluence mechanism and degree of freeze-thaw cycle and soluble salt content on strength,water stability and pore structure of lime-treated Ili loess,unconfined compressive strength test,disintegration test,permeability test and nuclear magnetic resonance test are employed here.The results show that the freeze-thaw cycle has obvious deterioration on the strength of lime-treated Ili loess.The deterioration of strength is serious in early freeze-thaw cycle stage,and the higher the content of soluble salt,the deterioration of strength due to freeze-thaw cycle.When the content of soluble salt is higher than 14 g/kg,the deterioration rate on the strength decreases.The disintegration of lime solidified Ili loess is accelerated with the increase of freeze-thaw cycles and soluble salt content,and the soluble salt content has a great effect on loess water stability.When the soluble salt content is higher than 8 g/kg,the disintegration rate increased significantly.The permeability increases with the increase of freeze-thaw cycle and soluble salt content,and the effect of freeze-thaw cycle is more significant than that of soluble salt content.When the content of soluble salt is 26 g/kg,the permeability coefficient decreases obviously due to the effect of osmotic suction.The modal size of loess pores increa-ses with freeze-thaw cycle increasing,which mainly affects the medium pores and large pores.And the effect of freeze-thaw cycle on pore structure of loess is higher than that of soluble salt content.Considering freeze-thaw cycle and controlling soluble salt content is very important for strength and water stability of soil in cold region.

关 键 词：石灰处理 伊犁黄土 冻融 易溶盐含量 强度劣化 水稳性 

分 类 号：TU432[建筑科学—岩土工程]