高寒山区岩体裂隙发育的边坡及复杂地层,常采用灌浆进行加固处理,浆液结石体常面临着强烈的冻融循环作用.通过对自主研发的黏度时变(SJP)浆液结石体进行冻融循环试验及电镜扫描方法,研究浆液结石体在冻融条件下的力学特性,讨论结石体的冻融损伤机理.试验结果表明:冻融条件下,SJP浆液结石体的耐久性能明显优于普通水泥结石体,随着冻融循环次数的增加,SJP浆液结石体的抗压强度和相对动弹性模量不断减小,而劈裂抗拉强度呈现先增加后减小的趋势;SJP浆液在助剂的综合作用下,C-S-H产量增多,并与纤维针状水化衍生物相结合,使得结石体内部的孔隙结构更加密实,有效地减缓了冻融损伤的积累,进而显著提高了其在冻融条件下的耐久性,从而更加适合在寒区工程建设中应用.%For the fractured rock slope and complex stratums, the grouting is a well-known crush rock treatment method in geotechnical engineering. However, the grout stone body usually face the damage of dramatic freezingthawing cycles. In this paper, the freezing-thawing cycle test and SEM test are used to study the stone body of selfdeveloped viscosity time-varying grout (SJP). The strength properties of SJP and blank cement stone body are study through compression test and wave test. According to the results of experiments, the mechanism of freezing and thawing damage is also discussed. The result shows that under the condition of freezing and thawing, the durability of SJP grout stone body is obviously better than blank cement stones. The compressive strength and relative dynamic elastic modulus of SJP grout stone decrease continuously with the increase of freeze-thaw cycles. But the tensile strength shows a trend of increasing firstly and then decreasing. All the decreasing rate of strengths of SJP is slower than the blank cement. When 2# added amount to 2.0, 3# added amount is 1.5％, SJP slurry stone body has the best frost resistance. The damage mechanism can be illustrated as follows. The production of C-S-H in SJP grout increases under the action of SJP additives, and combined with the fiber needle hydration derivatives, that makethe pore structure of stone body becomes denser than the blank cement. This characteristic slows the freeze-thaw damage accumulation effectively, thus its durability under the condition of freezing and thawing is improved effectively. Therefore, the SJP stone body is more suitable for application in alpine mountain area engineering construction.
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