Flowing water grouting is a big challenge in the tunneling and underground engineering. To enhance the early strength and grouting effectiveness of slurry for flowing water grouting, nano-CaCO₃ and fly ash were mixed with cement based grout. A series of physical simulation tests were conducted to simulate the flowing water grouting process in rough rock fracture, and investigate the effect of nano-CaCO₃ content on the fluid pressure and sealing efficiency of grouts. Results of viscosity tests show that the viscosity of grouts decreased with an increase of nano-CaCO₃ content. Scanning electron microscope (SEM) tests indicate that nano-CaCO₃ can promote the formation of fibrous hydrates and enhance the flowing water resistance of grouts. Increasing nano-CaCO₃ content resulted in the first increase while later decrease of maximal fluid pressure (MFP) and sealing efficiency (SE) of grouts. Reducing water cement ratio of grouts and incorporating fly ash can effectively improve the SE of flowing water grouting.

流水注浆是隧道和地下工程的一大挑战。为了提高用于流水注浆的浆料的早期强度和注浆效果，将纳米CaCO ₃和粉煤灰与水泥基浆液混合。进行了一系列物理模拟试验，模拟了粗糙岩石破裂中的流水注浆过程，并研究了纳米CaCO ₃含量对灌浆液压力和密封效率的影响。粘度测试结果表明，随着纳米CaCO ₃含量的增加，灌浆的粘度降低。扫描电子显微镜（SEM）测试表明，纳米CaCO ₃可以促进纤维状水合物的形成并增强水泥浆的耐流动水性。纳米CaCO ₃含量的增加导致水泥浆的最大流体压力（MFP）和密封效率（SE）首次增加，随后下降。降低水泥浆的水灰比并掺入粉煤灰可有效提高流水灌浆的SE。