摘要
粉土在中国分布广泛,工程中大量涉及,常表现为冻胀敏感性,在冻土地区工程建设中需重点考虑其冻胀特性。为减少粉土冻胀对工程的影响,基于环保的理念,以防腐处理后的麦秸秆作为加筋材料,将其切断后随机掺入粉土中;并对粉土和秸秆加筋粉土试样分别进行了开敞系统下的一维冻胀试验,重点研究了秸秆掺量和长度对粉土冻胀特性的影响。结果表明:秸秆加筋对粉土的冻胀有明显的抑制作用,少量的掺加(0.2%、0.4%)可将接近强冻胀的粉土改良为弱冻胀或不冻胀;在其他条件相同的情况下,试验范围内粉土的冻胀率随秸秆掺量的增加而线性增大,但总体远小于未改良土;秸秆掺量一定时,存在最优秸秆长度,在该长度下,秸秆加筋粉土的冻胀变形量和冻胀率均最小。
Silt is widely distributed in China and heavily involved in various engineering applications.The soil is high sensitive to frost heaving,hence the frost heaving characteristics should be taken into account when engi⁃neering is constructed in frozen regions.In order to restrain the impact of frost heaving of silt and reduce the car⁃bon footprint,the randomly distributed short-cut anticorrosive wheat straw is used to reinforce silt.Frost heav⁃ing tests are carried out on unreinforced and reinforced silt via one-dimensional freezing in the open system.The influence of straw content and straw length on the frost heaving characteristics of silt are investigated.The re⁃sults suggested that straw reinforcement can significantly inhibit the frost heaving of silt.A small amount(0.2%,0.4%)of the straw content can change the soil from strong frost heaving silt to weak frost heaving or non-frost heaving silt;for a given test condition,the frost heaving ratio of the soil increases linearly with the in⁃crease of straw content in the test range,but the values of reinforced soil are much smaller than that of the unrein⁃forced soil,and a small amount of straw content can inhibit the frost heaving;an optimum straw length can be found for a given straw content,at which both the frost heaving deformation and frost heaving ratio of reinforced soil reach the minimum value.
作者
彭丽云
华小宁
刘德欣
齐吉琳
PENG Liyun;HUA Xiaoning;LIU Dexin;QI Jilin(School of Civil and Transportation Engineering,Beijing University of Civil Engineering and Architecture,Beijing 100044,China;Multi-Functional Shaking Tables Laboratory,Beijing University of Civil Engineering and Architecture,Beijing 100044,China;Architectural Design&Research Institute of Tsinghua University,Beijing 100084,China)
出处
《冰川冻土》
CSCD
北大核心
2022年第1期241-250,共10页
Journal of Glaciology and Geocryology
基金
国家重点研发计划项目(2021YFF0306302)
国家自然科学基金项目(42172299
41972279)资助。
关键词
粉土
冻胀特性
秸秆加筋
冻胀变形
冻胀率
silt
frost heaving characteristics
reinforced with anticorrosive treated straw
frost heaving defor⁃mation
frost heaving ratio
