沈阳地铁隧道开挖蠕变效应

Creep effect of excavation of SHENYANG metro tunnel

为了预测沈阳地铁一号线在将来运营中的长期稳定性,采用FLAC数值模拟的方法,选取有代表性的青怀区间隧道,进行了沈阳地铁隧道长期蠕变效应数值分析。结果表明:就10年后隧道周边位移分布情形来看,拱顶的蠕变效应最大,其次依次为拱脚→底板→墙腰,说明拱顶处应作为长期蠕变分析时的重点,同时证实了地表蠕变效应最大的结论,体现了地铁浅埋隧道的变形特征;从分析点的位移-时间和位移速率-时间曲线,得出了隧道围岩属于稳定蠕变的结论,预测地铁隧道在今后运营过程中将处于长期稳定状态。该成果可为即将投入运营的沈阳地铁工程提供重要参考。

By the FLAC,a creep effect simulation of tunnel excavation of Shenyang metro No.1 line was conducted and its long stability was analyzed.It can provide benefic references for long running of SHENYANG metro tunnel.The results shows： As the displacement distribution around the point of view after 10 years,the creep effect of the vault,followed by the order of the arch wall → Floor → waist,is the maximum.The crown should be the focus of long-term creep analysis also confirmed that surface creep change the conclusions of the largest effect.It is reflected that the deformation characteristics of underground shallow tunnels.From the analysis of the displacement-time and displacement rate-time curves,it is obtained the conclusion of stable creep tunnel.It is forecasted that the operations of subway tunnel will be in the long-term stability in the future.The results are important references and can be put into operation for the subway project in Shenyang.