地面堆载对地铁隧道结构的影响

Influence of Ground Surcharge on Subway Tunnel Structure

基于某地铁工程为背景,建立地面堆载隧道结构模型,分析了地面堆载下地铁隧道的响应问题,揭示了隧道整体和隧道管片的变形规律。研究表明,隧道整体可分为基本不受堆载影响的区域Ⅰ和受堆载影响显著的区域Ⅱ,区域Ⅱ内环缝接头部分张开和错开现象显著,管片应力也很大;区域Ⅱ中地铁隧道的不均匀变形近似高斯曲线,在距离模型端部约40m的地方出现了隧道变形曲线的反弯点;拱腰处侧向错台峰值和拱顶处竖向错台峰值的发的位置相同,均在在隧道变形曲线的反弯点位置;隧道变形曲线的反弯点位置处的隧道拱顶和拱腰处的变形最为显著,是导致隧道防水失效的重要位置。

Based on a subway project,this paper establishes the structural model of ground surcharge tunnel,analyzes the response of subway tunnel under ground surcharge,and reveals the deforma-tion law of the whole tunnel and tunnel segments.The research shows that the whole tunnel can be divided into area I basically not affected by surcharge and areaⅡsignificantly affected by sur-charge.The opening and staggering of circumferential joints in ar-eaⅡare significant,and the segment stress is also great;In regionⅡ,the uneven deformation of the subway tunnel is similar to the Gaussian curve,and the reverse bending point of the tunnel defor-mation curve appears about 40m from the end of the model;The peak value of lateral abutment staggering at the arch waist and the peak value of vertical abutment staggering at the arch crown are at the reverse bending point of the tunnel deformation curve;The de-formation at the arch crown and waist of the tunnel at the reverse bending point of the tunnel deformation curve is the most signifi-cant,which is an important position leading to the waterproof fail-ure of the tunnel.