以石灰和偏高岭土为主要材料，制备一种适用于岩土类建筑的修补砂浆．用桐油和硬脂酸钙两种防水剂来改善砂浆的耐水性，研究桐油和硬脂酸钙对砂浆强度、反应过程、吸水率和软化系数、干燥收缩的影响，并通过XRD和SEM 对砂浆进行物相分析和微观形貌观测．结果表明：桐油和硬脂酸钙可以显著提高石灰偏高岭土砂浆的耐水性，可使吸水率下降至2．5％以下；桐油和硬脂酸都会阻碍偏高岭土的火山灰反应，在一定程度上降低砂浆的强度，但28 d的抗压强度仍在5 M Pa以上，达到天然水硬性石灰N HL5的强度等级；桐油和硬脂酸钙会影响石灰偏高岭土砂浆的微观形态和结构，桐油使产物的颗粒更细小、更致密，硬脂酸钙则会使产物结构比较疏松．综合考虑砂浆强度、耐水性等因素，得出桐油和硬脂酸钙的最佳掺量分别为5％和1．5％．%A kind of repair mortar for geotechnical building was prepared with lime and metakaolin as major materials .Two kinds of water‐repellent admixtures (tung oil and calcium stearate) were used to im‐prove the water resistance of the mortars .Different properties of the mortars were evaluated ,such as strength ,the process of reaction ,water absorption ,softening coefficient and shrinkage .Phase and micro‐structure analysis of the mortars were carried out through XRD and SEM .The results show that tung oil and calcium stearate can improve water resistance of the mortars significantly .Water absorption of the mortars with tung oil or calcium stearate can be below 2 .5% .Tung oil and calcium stearate hinder the poz‐zolanic reaction of metakaolin ,which as a result decrease the mortars’ strength .But 28 d compressive strength of the mortars are all above 5 MPa .Also ,tung oil and calcium stearate can regulate the growth of products and affect the micromorphology and structure of mortars .Tung oil make the particle size smaller and the structure more compact ,while calcium stearate leads to a looser structure .Considering both the mortar strength and water resistance ,the optimum dosage of tung oil and calcium stearate was 5% and 1 .5% respectively .
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