针对高压水工隧洞局部不良地质体中水泥浆难以充分处理微细裂隙、单一化学浆材经济性不足的问题，建立兼顾承载、防渗与施工安全的水泥-化学复合灌浆方法。对梅州、阳江、深圳和清远4座抽水蓄能电站的地质条件、水头、生产性试验、施工记录和灌后检测结果进行对比，基于水头确定性能需求、地质与结构响应约束可实施参数的双控原则，归纳适用边界、孔网、压力路径、材料及质量控制方法。工程应用表明，梅州、深圳和清远抽水蓄能电站分别验证了该技术在岩脉及断层段、断裂密集带和Ⅴ类泥化围岩中的适用性；阳江抽水蓄能电站在800 m超高水头条件下完成了8~10 MPa级灌浆。灌后透水率均可控制在1.0 Lu以内，高压水道充水一次成功。由此形成了地质定参数、材料分级选、工艺动态控制的高压复合灌浆技术，可为类似工程提供参考。

Objectives: To address the problem that single-type cement grouting cannot simultaneously achieve reinforcement and anti-seepage in local adverse geological bodies of high-pressure tunnels, and to fill the research gap that grouting parameters under ultra-high water heads lack systematic guidance, a transferable design and construction method for cement-chemical composite grouting was established. The method was intended for new pumped-storage projects where otherwise competent rock masses contain local faults, altered dikes, densely jointed zones, or microfracture networks.

Methods: Design documents, field tests, construction records, quality inspections, and initial-operation data from the Meizhou, Yangjiang, Shenzhen, and Qingyuan pumped-storage power stations were compared. The maximum static heads ranged from approximately 426 to 800 m. Rock-mass classes, fracture scales, permeability, grouting pressures, hole spacing, hole depth, epoxy properties, pressure-flow histories, lining deformation, and post-grouting permeability were jointly examined. The relationship between water head and process parameters was analyzed by separating two controls. Water head was treated as the external hydraulic demand governing anti-seepage reserve, material verification level, and target pressure range. Geological quality and lining safety were treated as internal constraints governing hole density, treatment depth, allowable pressure, pressure-rise rate, and intermittent grouting need.

Results：Composite grouting was shown to be appropriate only after rock cover, minimum principal stress, and overall stability had satisfied the applicability requirements of a rock-bearing lining. Cement grout was used first to fill medium and large fractures, restrict uncontrolled grout loss, and form a macroscopic load-transfer skeleton. Low-viscosity modified epoxy grout was then used to penetrate microcracks, weathered contacts, mud-filled interfaces, and residual seepage paths. For preliminary design, head ranges of 100~400, 400~600, and 600~800 m were associated with progressively higher material-performance requirements; however, grouting pressure was not determined by head alone. Weak or highly altered rock required closer holes, shorter stages, lower pressure-rise rates, and stricter pressure limits, whereas competent rock under an ultra-high head could accept higher terminal pressures after full-scale field verification. The verified engineering ranges were 1.5~3.0 m for row spacing, 3~12 m for normal hole depth, 8~20 m for fault-zone reinforcement depth, 0.5~10 MPa for cement grouting pressure, and 2~8 MPa for chemical grouting pressure. When the internal water pressure exceeded 5 MPa, additional verification of splitting tensile strength (not less than 10 MPa) and elastic modulus (greater than 300 MPa) of the epoxy grout was recommended. The Meizhou project adopted differentiated chemical pressures of 2~6 MPa for altered dikes and faults; post-grouting permeability was below 1.0 Lu, ultrasonic velocity increased by 3%~10%, and initial filling was successful. The Yangjiang project used 8~10 MPa cement grouting and chemical grouting up to 8 MPa under an approximately 800 m head, with pressure-flow product and lining-uplift controls. Shenzhen verified full-hole chemical grouting for holes not deeper than 7 m, and Qingyuan treated kaolinized Class V rock by pressure-limited, intermittent, same-hole composite grouting. Cement-grouted zones generally reached 2.0~3.0 Lu, whereas chemically strengthened zones could be controlled within 1.0 Lu.

Conclusions: A practical workflow was formed comprising hydraulic and geological zoning, applicability verification, treatment-object identification, material selection, productive field testing, parameter design, dynamic construction control, and multi-index acceptance. The results demonstrated that water head should define the required performance level, while geology and structural response should determine the executable process parameters. This dual-control distinction prevented both insufficient reinforcement and unsafe pressure escalation. The core innovation lies in the water-head-geology dual-control criterion and the differentiated parameter system established through multi-project comparison, which provides a quantitative basis for grouting design. The proposed workflow can guide engineers in deciding where composite grouting is necessary, how holes and materials should be selected, how pressures should be increased and limited, and how the final treatment should be verified in a new high-pressure tunnel.