The region belong to high geostress area . in the preceding excavation of 4km long exploratory tunnel, several bigger flows had taken place . the maximal flux approached 4.91m3 / s and the maximal water pressure is 10.22mpa 在前期4km長(zhǎng)探洞施工過(guò)程中,曾發(fā)生多次較大涌水,單點(diǎn)最大涌水量達(dá)4.91m~3s,長(zhǎng)探洞封堵后最大水壓力達(dá)10.22mpa,工程區(qū)高外水壓力問(wèn)題突出。
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 計(jì)算結(jié)果表明,如果能使錦屏工程引水隧洞灌漿圈圍巖具有較好的防滲性能,將高外水壓力控制在灌漿圈以外,再配合透水性相對(duì)較好的支護(hù)結(jié)構(gòu)以及排水措施,使灌漿圈圍巖成為主要承載結(jié)構(gòu),并使襯砌結(jié)構(gòu)和灌漿圈共同承載,是可以保證圍巖的穩(wěn)定和支護(hù)結(jié)構(gòu)安全的。