水泥基气泡轻质土冻融耐久性的研究  

Study on freeze-thaw durability of cement-based foamed lightweight soil

作　　者：朱晨 张立群[1] 马江平 王雅超 石玉鑫 吴磊 李元博 李少刚 蒋明学 ZHU Chen;ZHANG Liqun;MA Jiangping;WANG Yachao;SHI Yuxin;WU LeiLI Yuanbo;LI Shaogang;JIANG Mingxue(Hebei University of Architecture,Zhangjiakou,Hebei 075000;Zhangjiakou Tongtai Holding Group Co.,Ltd,Zhangjiakou,Hebei 075000)

机构地区：[1]河北建筑工程学院,河北张家口075000 [2]张家口通泰控股集团有限公司,河北张家口075000

出　　处：《河北建筑工程学院学报》2024年第1期66-73,共8页Journal of Hebei Institute of Architecture and Civil Engineering

基　　金：河北建筑工程学院创新基金项目(XY2023032)。

摘　　要：气泡轻质土作为一种新型材料因其具有轻质性、自密实、保温等优良特性,在寒区路基工程中有更加广泛的应用趋势。为了降低气泡轻质土的工程造价、充分利用当地资源,分别采用0%、20%、30%、40%粉质黏土和10%的粉煤灰替代部分水泥制备水泥基气泡轻质土,并开展了500 kg/m~3、600 kg/m~3、700 kg/m~3、800 kg/m~3湿密度下水泥基气泡轻质土的冻融耐久性试验。评价了不同粉质黏土掺量和湿密度对水泥基气泡轻质土冻融耐久性的影响。结果表明:(1)从质量损失率分析,掺量为20%、30%试件的质量损失率相对较小,冻融耐久性较好。(2)通过相对动弹模损失量分析,粉质黏土掺量40%和湿密度为500 kg/m~3试件的冻融耐久性较差,不宜使用。因为粉质黏土消耗了水泥水化作用需要的水分,且泡沫越多,试件内部越稀疏。(3)建立了以冻融循环次数、粉质黏土掺量为因子的相对动弹性模量预测模型公式,该模型验证结果较好且公式结构简洁,便于应用到实际工程中。Bubble lightweight soil,as a new type of material,has become more widely used in roadbed engineering in cold regions due to its excellent properties such as lightweight,self compacting,and thermal insulation.In order to reduce the engineering cost of foamed lightweight soil and fully utilize local resources,cement-based foamed lightweight soil was prepared by replacing part of cement with 0%,20%,30%,40%silty clay,and 10%fly ash,respectively.Freeze thaw durability tests were conducted on cement-based foamed lightweight soil at wet densities of 500 kg/m 3,600 kg/m 3,700 kg/m 3,and 800 kg/m 3.The effects of different amounts of silty clay and wet density on the freeze-thaw durability of cement-based foamed lightweight soil were evaluated.The results show that:①From the analysis of mass loss rate,the mass loss rate of specimens with 20%and 30%dosage is relatively small,and the freeze-thaw durability is good.②According to the analysis of relative dynamic modulus loss,the freeze-thaw durability of the specimens with a 40%content of silty clay and a wet density of 500 kg/m 3 is poor and should not be used.Because silty clay consumes the water required for cement hydration,and the more foam,the thinner the inside of the test piece.③A relative dynamic elastic modulus prediction model formula was established based on the number of freeze-thaw cycles and the content of silty clay as factors.The model has good validation results and a simple formula structure,making it easy to apply to practical engineering.

关 键 词：水泥基气泡轻质土 粉质黏土 冻融循环 相对动弹性模量 

分 类 号：U416.1[交通运输工程—道路与铁道工程]