盾构作为地铁隧道施工的主要设备与作为地铁隧道永久衬砌的管片应用均非常广泛，因此管片选型的好坏直接影响到地铁隧道的精度和质量。根据常用管片的特点，着重介绍现今应用比较普遍的等腰梯形转弯环管片的楔形量计算、管片排版计算及盾构管片选型依据，并计算出常用管片的最大转弯半径，对管片造型与组织管片生产具有一定的指导作用。

Shield machine is main equipment -5 in metro tunnel construction and the pipe segments on it, as a permanent lining of the metro tunnels, has a wide application, and therefore, model selection of the pipe segments has a direct effect on the accuracy and quality of metro tunnels. Based on the characteristics of the pipe segments, this thesis will focus on wedge calculation of isosceles trapezoid bend segment ring, pipe segments arrangement calculation and model selection basis of shield machine pipe segments, and work out the maximum bend radius of the pipe segments often used, which will direct model selection of pipe segments and organization of pipe segments production.