锦屏二级水电站1#引水隧洞岩爆洞段数值分析

以锦屏二级水电站1#引水隧洞强岩爆洞段为例,运用RFPA对隧洞上半断面开挖进行数值分析,通过对隧洞破坏模式及其围岩的应力分析,在强岩爆洞段上半断面开挖过程中,围岩首先在边墙附近出现破坏,然后不断向拱肩方向扩展,即应力首先在洞壁附近产生应力集中,导致围岩产生损伤,随着损伤范围的扩大,高应力场向远离洞壁的方向发展,同时洞壁...

Numerical Analysis of Intensive Rockburst Section of No.1 Headrace Tunnel in Jinping H Hydropower Station

Taking the section of No.1 headrace tunnel in JinpingⅡhydrop-ower station in which intensive rockburst may happen for example,RFPA(realistic failure process analasis) was used to analyze the process of the unloading excavation.The tunnel was excavated by the method of drill and blast,and the upper section was first shaped in excavation.By means of analyzing the failure patterns of tunnel and stress distribution of surrounding rock,the results indicated that the failure firstly happened at the foot of wall,and then the area of failure enlarged to spandrel,that is the stress firstly concentrated at the wall of tunnel,and leads to the damage of surrounding rock.As the extension of damage occurs,the field of high stress extended to the position far from the wall.At the same time,the stress around the wall became smaller,especially at the foot of wall.The result was confirmed to tally with the actual situation excellently.The result was expected to be used to analyze other similar tunnels.