In addition , this paper carry out successfully the support design practice in the preceding excavation of 4km long exploratory tunnel . according to the thesis research results , the following conclusion can be drawn . if the grouting rock can possess sound anti - seepage capability and the liner structure can hold higher hydraulic permeability relatively , and if the adjoining rock can be made as primary load - bearing structure by construction measure , the stability of country rock and the safety of liner structure will be guaranteed 计算结果表明，如果能使锦屏工程引水隧洞灌浆圈围岩具有较好的防渗性能，将高外水压力控制在灌浆圈以外，再配合透水性相对较好的支护结构以及排水措施，使灌浆圈围岩成为主要承载结构，并使衬砌结构和灌浆圈共同承载，是可以保证围岩的稳定和支护结构安全的。
