楔形环管片纵向接头对施工荷载力学响应研究

楔形环管片是盾构隧道曲线段的重要组成部分。以珠海-澳门轻轨某急弯隧道为例,利用ANSYS有限元软件计算了楔形环管片在不同管片幅宽、楔形量、隧道曲率半径、千斤顶压力等条件下管片纵向接头的受力情况,重点分析了管片环间接头的最大正负弯矩。研究结果表明:随着盾构隧道曲线半径减小,正负最大弯矩均增大,不同隧道转弯半径下,管片最大正负弯矩均随接头抗弯刚度的增大而增大;不论正负弯矩,均有管片幅宽越小最大弯矩越大的现象。不同管片幅宽下,管片最大正负弯矩均随接头抗弯刚度的增大而增大;曲线半径为150 m时,最大正弯矩基本随着千斤顶压力呈线性增大的趋势,最大约为1 180 k N·m。研究结果对今后的急弯盾构隧道管片设计有一定的指导意义。

Mechanical response of wedge ring segment longitudinal joints to construction load

Wedge ring segment is an important component of shield tunnel. Taking one sharp bend tunnel in Zhuhai-Macao light rail as an example, the stress of wedge ring segments in different ring width, wedge-shaped amplitude, radius of curvature of the tunnel, pressure of jack lift, and the biggest positive and negative moments at the joint of wedge ring are calculated by ANSYS finite element software. The results show that the maximum bending moment increases with radius decrease of shield tunnel. Regardless of radius of the tunnel, the maximum positive and negative bending moments of the segment increase with the flexural rigidity of joint. For both positive and negative bending moments, the smaller of ring width is, the bigger of the maximum bending moment is. For different ring widths, the maximum bending moment increase with the flexural rigidity of joint. The maximum positive bending moment basically increases linearly with the jack pressure when the radius of the curve is 150 m, and the maximum values is about 1180 kN·m. The results of the study are helpful to the design of the ring segment of shield tunnel.