地铁盾构通用环管片楔形量计算方法研究

通用环管片通过有序旋转拼装形成地铁盾构隧道，而管片楔形量的变化将影响通用环管片线路拟合及施工纠偏的能力。为明确地铁盾构通用环管片楔形量的计算方法，对计算管片楔形量的类似通缝、紧邻交错、非对称间隔交错和对称间隔交错4种计算方法进行详细介绍与比较，然后结合天津市滨海新区轨道交通Z2线工程，系统分析几种楔形量计算方法的线路高程拟合情况和不同楔形量通用管片对整个典型区间的拟合情况，最后提出地铁盾构通用环管片楔形量的多层次控制设计流程。研究结果表明： 对称间隔交错计算方法更适用于初步计算通用环管片楔形量，并且将最小曲线半径折减50~100 m能够更快地确定初步设计的楔形量，同时有必要对管片进行设计排版来验证计算得到的管片楔形量是否满足控制要求，并且在验算时线路高程拟合偏差是一项重要的控制因素。

Calculation Method for Taper of Universal Ring Segment in Metro Shield Tunnel

The universal ring segment can be orderly assembled to form metro shield segment, and the capacity of line fitting and construction rectification of the universal ring segment can be affected by taper of segment. In order to determine the calculation method for taper of universal ring segment in metro shield tunnel, detailed comparison among 4 kinds of methods for calculating the taper of the universal ring segment, i.e. method similar to the straight joint, adjacent interleaving, asymmetric interval interleaving and symmetric interval interleaving, are carried out. And then, by taking Line Z2 project of Tianjin Binhai New District rail transit for example, the elevation fitting situation of DTA (design axis of tunnel) by several calculation methods for the taper of universal ring segment and the fitting situation of the universal ring segment with different tapers to the whole typical interval are systematically analyzed. Finally, a multi level control design flowchart for calculating the taper of universal ring segment in metro shield tunnels is obtained and proposed. The study results show that: (1) The symmetric interval interleaving calculation method is superior to others when preliminarily calculating the taper of universal ring segment. (2) The preliminarily designed taper of universal ring segment can be determined rapidly by reducing the minimum curve radius by 50 100 m. (3) It should be verified that whether the calculated taper of the universal ring segment meets the control requirements or not; and the elevation deviation of DTA is an important control factor.