煤渣改良土作为路基填土的强度及冻胀特性  

Strength and Frost Heave Characteristics of Cinder Improved Soil as Subgrade Filler

作　　者：任昆 白海峰[1] 栾海洋 张向东[2] 黄志军[3] REN Kun;BAI Haifeng;LUAN Haiyang;ZHANG Xiangdong;HUANG Zhijun(Dalian Jiaotong University,Dalian,Liaoning 116028,China;Liaoning Technical University,Fuxin,Liaoning 123000,China;Lanzhou Jiaotong University,Lanzhou,Gansu 730070,China)

机构地区：[1]大连交通大学,大连116028 [2]辽宁工程技术大学,阜新123000 [3]兰州交通大学,兰州730070

出　　处：《铁道工程学报》2020年第7期1-6,共6页Journal of Railway Engineering Society

基　　金：国家自然科学基金资助项目(51774166);高等学校博士学科点专项科研基金项目(20112121110004)。

摘　　要：研究目的:为研究煤渣改良土的强度及冻胀特性,开展不同配比及龄期下的三轴CU试验及冻胀试验,获得不同冻融循环条件下煤渣掺量及养护龄期对土体强度及冻胀率的影响,并建立预测冻胀率发展的GM(1,1)模型,分析煤渣改良土的防冻机理.研究结论:(1)随煤渣掺量的增加,改良土的强度出现先增大后减小的变化趋势,改良前后土体的黏聚力变化较大,而内摩擦角的变化不明显;(2)煤渣掺量及养护龄期对土体冻胀率的发展起到抑制作用,可减弱冻胀带来的影响;(3)冻融循环作用加剧了土体的劣化程度,使冻胀率有所提高,其中前5次冻融循环的影响较为明显;(4)根据冻胀率的发展规律所建立的GM(1,1)模型可以较好地预测冻胀率的变化,可为季冻区工程建设提供参考.Research purposes:To study the strength and frost heave characteristics of the cinder improved soil,the triaxial CU test and frost heaving test were carried out under different proportions and ages.The effects of cinder content and curing age on soil strength and frost heave ratio under different freeze-thaw cycles were obtained.The GM(1,1)model was established to predict the development of frost heave ratio,and the anti-freezing mechanism of cinder improved soil was analyzed.Research conclusions:(1)The strength of cinder improved soil increases first and then decreases with the increase of cinder content.The cohesion of soil changes greatly before and after improvement,but the change of internal friction angle is not obvious.(2)The content of cinder and curing age can inhibit the frost heaving rate in soil and weaken the influence of frost heaving.(3)The freeze-thaw cycles aggravate the deterioration of soil,and improve frost heaving rate,among which the first five freeze-thaw cycles have more obvious effects.(4)The GM(1,1)model established according to the development law of frost heaving rate can better predict the change of frost heaving rate,which can provide reference for the construction of seasonal frozen area projects.

关 键 词：煤渣改良土 冻融循环 强度 冻胀率 灰色理论 

分 类 号：U419.92[交通运输工程—道路与铁道工程]