水泥基复合注浆材料在云桂铁路岩溶地基加固工程中应用研究

以云桂铁路DK638+665~+685段路基岩溶整治为背景，采用对照试验方法，对复掺速凝剂（SA）、减水剂（SP）和高吸水性树脂（SAP）的泵送性能和工程适用性进行了对比评价。结果表明:SA，SP，SAP实现了对水泥浆液的不同泵送期的定量控制，与普通水泥浆液相比，具有稳定性强、材料流失小等优点，与水泥-水玻璃浆液（C-S）相比，可以有效提升体积稳定性和后期强度。基于试验成果，提出了岩溶路基三序孔注浆液材料选择原则，同时对复合注浆施工工艺进行了探讨，提出“托底-渗透”复合注浆新模式；最后，从压水试验和取芯试验结果得出了复合注浆治理效果良好的结论。

Study on Application of Cement-based Composite Grouting Materials in Karst Subgrade Reinforcement Project of Nanning—Kunming High-speed Railway

Taking the karst treatment of section DK638+665~+685 subgrade of Nanning-Kunming high-speed railway as an example, the pumping performance and engineering applicability of composite accelerator (SA), water reducing agent (SP) and super absorbent resin (SAP) are compared and evaluated by using the contrast experiment method. The results show that:SA, SP and SAP have realized the quantitative control of different pumping periods of cement slurry. Compared with ordinary cement slurry, SA, SP and SAP have the advantages of strong stability and small material loss. Compared with C-S, SA, SP and SAP can effectively improve the volume stability and later strength. Based on the test results, the principle of material selection of three sequence hole grouting fluid for karst subgrade is proposed, at the same time, the construction technology of composite grouting is discussed and a new mode of composite grouting of "bottom supporting and permeability" is put forward. Finally, the conclusion that the composite grouting has good treatment effect from the results of water pressure test and core taking test is drawn.