高寒地区水镁石纤维早强型水泥稳定碎石的路用性能研究  

Study on the performance of gravel road stabilized by early strength agent and brucite fibers in alpine regions

作　　者：盛燕萍[1] 李亮亮 关博文[1] 周辉丽 何锐[1] 陈华鑫[1] SHENG Yanping;LI Liangliang;GUAN Bowen;ZHOU Huili;HE Rui;CHEN Huaxin(School of Materials Science and Engineering, Chang＇an University, Xi＇an 710064, China;Qinghai Research Institute of Transportation, Xining 810008, China)

机构地区：[1]长安大学材料科学与工程学院,陕西西安710064 [2]青海省交通科学研究院,青海西宁810008

出　　处：《冰川冻土》2018年第2期355-361,共7页Journal of Glaciology and Geocryology

基　　金：国家重点研发计划项目(2017YFB0309903-02);青海省科技计划项目(2017-ZJ-763;2017-ZJ-764;2017-ZJ-715);中央高校基本科研业务费专项资金项目(310821171115;300102218502)资助

摘　　要：为了提高水泥稳定类基层在高寒地区的适用性,提出在基层中复掺基层早强剂和水镁石矿物纤维使其达到早强抗裂作用,通过研究其抗压强度、劈裂强度、收缩特性以及抗冻性能,分析水镁石矿物纤维在水泥稳定碎石中的作用机理。试验结果表明:复掺基层早强剂和水镁石矿物纤维后,20℃养护条件下基层3 d抗压强度与劈裂强度分别为其28 d的85%和76%,-15℃低温养护条件下3 d抗压强度与劈裂强度分别为其28 d的69%和68%;抗收缩性能在加入水镁石纤维后有较大提高,纤维掺量为4%时,干缩系数与温缩系数比未掺时分别降低约92%和48%;抗冻性能也因掺入水镁石纤维而有所改善,纤维掺量为4%时基层28 d冻融残留抗压强度比(BDR)为0.96%。复掺水镁石纤维与基层早强剂,既能有效保证高寒地区水稳碎石的强度,又能避免基层在干燥气候中的收缩开裂和在低温、变温环境中的温缩开裂,其中水镁石纤维最佳掺量为4%。Aiming to improve the adaptability of cement stabilized macadam base in the alpine regions,both early strength agent and brucite fiber were added to the basement layer. The performances,such as compressive strength,splitting tensile strength,shrinkage and frost resisting property of the base were studied. Also,the effect of adding brucite mineral fiber to cement-stabilized macadam was analyzed. Test results showed that after adding early strength agent and brucite fiber both,compressive strength and the splitting tensile strength of the base reached 85% after 3 days and reached 76% after 28 days,respectively,under curing at 20 ℃. Meanwhile,compressive strength and splitting tensile strength of the base in 3 days reached 69% and 68% in 28 days,respectively,under curing at-15 ℃. The anti-shrinkage properties of the base was improved by adding brucite fiber at the optimum mix amount of 4%,as a result,the dry shrinkage coefficient and shrinkage coefficient of the base were reduced by about 92% and 48%,respectively,compared to that without brucite fiber. Meanwhile,frost resistance of the base was improved as well,for example,when the optimum mix amount was also 4%,the BDR of the base would be 0. 96%. Through the experiments,the following conclusion can be drawn： the addition of both early strength agent and brucite fiber in the base can not only improve the strength of the base but also prevent shrinkage and lowtemperature cracking. The optimum mix amount is 4% in the base.

关 键 词：高寒地区 水泥稳定碎石 水镁石纤维 基层早强剂 路用性能 

分 类 号：U414.1[交通运输工程—道路与铁道工程]