重塑条件对红黏土力学特性影响试验研究  

Effect of remolding conditions on mechanical properties of laterite

作　　者：冉宇玲 杨秀娟[1] 柏巍[2] 樊恒辉[1] 李科 RAN Yuling;YANG Xiujuan;BAI Wei;FAN Henghui;LI Ke(College of Water Resources and Architectural Engineering,Northwest Agriculture and Forestry University,Yangling 712100,China;State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics of Chinese Academy of Sciences,Wuhan 430071,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]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,湖北武汉430071

出　　处：《人民长江》2024年第1期229-235,共7页Yangtze River

基　　金：国家自然科学基金面上项目(41772339);陕西省科技发展计划项目(2023-JC-YB-463)。

摘　　要：重塑条件是影响重塑土样相关力学特性的重要因素,为分析堤防建设的土工试验中各重塑条件对重塑土力学特性的影响,采用不固结不排水三轴试验研究了不同重塑条件(碎土方式、含水率和制样方式)对重塑红黏土力学特性的影响,并结合扫描电镜图像揭示了相关重塑条件对力学强度特性的影响机理。结果表明:在含水率较低时,影响红黏土重塑样强度的主要因素为制样方式;当含水率升高后,碎土方式成为主要的控制因素;结合微观试验进一步说明不同碎土方式得到不同级配的土粒,机械碎土方式会使得土颗粒集聚成不同数量的“粗颗粒”,改变土粒级配从而影响相关力学特性;不同制样方式导致土颗粒发生不同的有序排列,进而使得土体抗剪强度发生变化。The remolding conditions play a crucial role in influencing the mechanical properties of remolded soil samples.To analyze the impact of various remolding conditions on the mechanical properties of remolded soil in geotechnical tests for embankment construction,unconsolidated undrained triaxial tests were conducted in this study to investigate the effects of remolding conditions(different crushing methods,moisture contents,and sample preparation methods)on the mechanical properties of remolded laterite.The mechanism influencing the mechanical strength properties due to remolding conditions was elucidated through scanning electron microscopy(SEM)images.The results indicate that when the moisture content is low,the main factor affecting the strength of laterite is the preparation method.When the moisture content increases,the method of soil crushing becomes the main control factor.Combining with the microscopic test,it further reveals that different soil crushing methods can obtain soil particles of different gain size distributions.Mechanical crushing methods will make the soil particles gather into different amounts of"coarse particles",change the soil grain distribution and thus affect the relevant mechanical properties.Different sample preparation methods are reflected in the different ordered arrangement of soil particles,thus changing the shear strength of soil.

关 键 词：红黏土 重塑条件 力学特性 不固结不排水三轴试验 微观分析 

分 类 号：TU41[建筑科学—岩土工程]