以上海地铁13号线区间盾构隧道管片环为工程实例,比选确定了管片径向拼装偏差各情况的防水最不利管片环初始结构,对外荷载作用下以上各防水最不利管片环防水失效时的收敛变形值计算后,以该值变化量对管片环防水性能下降程度进行了量化。认为:管片径向拼装偏差导致接头错台及腰部接头外侧张开的同时发生,后者对管片环防水性能影响更甚;1个接头发生错动情况的防水最不利管片环结构收敛变形特征值为1.53‰D,小于无拼装偏差情况特征值的1/2,环内错动接头数量越多,该特征量越小;当拼装偏差接头个数大于3时,其防水最不利管片环出盾尾前已防水失效。根据以上研究结论,提出了一些对管片环拼装质量控制及其运营期防水可靠性监测具有参考意义的建议。
Taking the segment rings of shield tunnel of Shanghai Metro Line 13 as a study case, the initial structure of segment rings with the worst waterproofness under various error cases is determined. The decrease of waterproofness is quantified through change of convergence of segment ring as its waterproofness fails. The results indicate that the radial erection error of segments causes the joint dislocation and external opening of waist joints simultaneously, and the latter is worse to the initial waterproofness than the former. As the waterproofness fails, the convergence of segment rings with the worst waterproofness in one joint error case is 1.53‰D, it is less than a half of that in the no error case, and the convergence further decreases as the number of erroneous joints increases. If there are more than three erroneous joints, the waterproofness of segment rings with the worst waterproofness will fail before they come out of shield rear. According to the above conclusions, some recommend actions are proposed for the quality control of segment erection during construction phase and the waterproof monitoring of segment rings during service phase.