研究目的:大丽铁路三叠系松桂组页岩型隧道具有特定构造环境下的工程条件，破碎页岩遇水软化膨胀 等原因易引起初期支护变形，给隧道施工带来较大困难，因此，有必要研究该类围岩特性及隧道施工对策。
研究结论:根据页岩(砂质页岩、炭质页岩)的结构特征，提出了相应的施工对策，如对开挖外轮廓进行调 整、增大预留变形量、采用三台阶法施工、设置全环工18工字钢架、调整系统锚杆长度、加强监控量测等，这些措施较好地抑制了初期支护变形。
Research purposes: There are some specifical engineering-geology conditions on tunnel through shale( T3sn) in Dali-Lijiang railway. Due to some peculiar characters of cracked with tectonics and intenerated and inflated with water for shale(T3sn)，a great deal of difficulties are brought on construction of tunnel. It is necessary to investigate construction countermeasures corresponding shale ( T3sn).
Research conclusions: Based on the characters of shale(T3sn)，a lot of construction countermeasures are adopted, including adjustment tunnel profile, accretion premeditate distortion, three-sidestep-diging into, setting steel structure, adjustment length of anchor-pole, strengthening inspection and so on. As a result of above measures, initial stage shoring distortion of tunnel is restrained effectively.
PDF(342 KB)
