和龙沿江公路傍山隧道偏压特征分析

傍山隧道作为一种偏压隧道，其潜在的灾害问题非常突出。通过具体的工程实例，采用有限元方法进行了隧道偏压特征分析，阐述了偏压隧道围岩受力变形特征。在应力特征上，表现为临江面硐壁应力较内壁应力值偏高，最大值达1.36 MPa，而内壁应力最大值仅为1.13 MPa。偏压主要集中在外侧硐底拱肩处,即内、外两侧拱肩处围压不对称分布，外侧拱肩部位形变压力增大。位移特征上，表现为以内侧硐底为支点，向临空面方向偏移的扁形曲线。其水平向的最大位移偏移量约7.4 cm，竖直方向最大位移偏移量约4.1 cm。且边墙位移不对称分布，不出现底拱位移曲线的特点。

Analysis on the Asymmetrically Loaded Characteristics of the Mountain-Adjacent Tunnel

Mountain-adjacent tunnel is one of the asymmetrically loaded tunnel and its potential are very predominant.The characters of asymmetrically loaded tunnel were analyzed by FEM through specific project.At the same time the stress and deformation were formulated.With regard to the stress characteristic,the stress of the cave wall which faces the river is a little higher than the stress of inside wall,the maximum stress of the outside wall reaches 1.36 MPa while the inboard wall is only 1.13 MPa,the asymmetrically loaded parts mainly centre in the cave bottom and the spandrel,namely the distribution of the stress is asymmetrical between inside and outside spandrel,and the deformation pressure of outside spandrel increases.The displacement characteristic show that the cave bottom as curve fulcrum and displacement takes on a flat shape curve which offsets to the empty direction.The maximum horizontal displacement offset is about 7.4cm and the vertical is only about 4.1 cm.Distribution of the wall displacement is unsymmetrical and there is no character in consistent with displacement curve of cave bottom.The analysis result has offered the theoretical foundation for engineering design.