【摘要】 为满足施工要求制备与各类较硬岩石波阻抗匹配的水泥基微膨胀回填材料，采用普通硅酸盐水泥、矿粉、中级砂等为原料，引气剂为密度和波速调节材料，通过改变水胶比、砂胶比与引气剂质量分数，探究其对水泥基微膨胀材料抗压强度、密度、波速和波阻抗的影响规律；测量各组材料的流动度和竖向膨胀率是否满足回填施工要求；通过微观测试，探究引气剂质量分数对水泥基微膨胀材料内部孔隙结构与孔隙率的影响规律。结果表明：引气剂的加入在水泥基微膨胀材料内部引入气泡，随引气剂质量分数增加，水泥基微膨胀材料内部孔隙率逐渐增大，抗压强度、密度、波速与波阻抗均下降；所制备出的水泥基微膨胀材料可满足的波阻抗范围为4.67～10.3 kt·m^-2·s^-1,能够匹配各类常见较硬岩石波阻抗；对水泥基微膨胀材料28 d波阻抗进行多元线性回归分析，得到精度较高的回归模型，实际应用时注浆效果较好，可用于岩石波阻抗匹配材料的快速制备。更多还原

【Abstract】 In this paper, cement-based micro expansion backfill material is prepared by using 52.5R ordinary portland cement, ground granulated blast furnace slag, intermediate sand, air entraining admixture, water-reducing admixture, expansive material, and other raw materials. Its density and wave velocity are adjusted by changing the water-cement ratio, sand-cement ratio and air-entraining admixture mixing amount to match the wave impedance of the hard rocks. And its fluidity and vertical expansion rate are adjusted to meet the requirements of backfill construction. On this basis, the effect of water cement ratio, sand cement ratio, and air entraining agent mass fraction on the compressive strength, porosity, and wave impedance of cement-based micro expansion materials is studied. The results show that the addition of air entraining admixture introduces air bubbles inside the cement-based micro expansion materials. With the increase of the dosage of air entraining admixture, the internal porosity of the cement-based micro expansion materials gradually increases, and the compressive strength, density, wave velocity, and wave impedance all decrease. The prepared cement-based micro expansion materials can meet the range of wave impedance of 4.67～10.3 kt·m^-2·s^-1. It can match the wave impedance of various kinds of common hard rocks. The multiple linear regression analysis of 28 d wave impedance of cement-based micro expansion materials yields a regression model with high accuracy and better grouting effect in practical application, which can be used for the rapid preparation of rock wave impedance matching materials.更多还原