西堠门大桥钢加劲梁制造时采用水平预拼装的方法，为了保证梁段的制造竖曲线形，应先根据设计数据模拟计算得到竖曲线形相关参数，在水平预拼装时进行控制、调整，最后检测线形的精度，保证线形的正确性。

Horizontal preframe method was adopted when steel stiffening girders of Xihoumen Bridge were fabricated, i.e. the steel box girders were pre-assembled in horizontal direction. To insure the vertical line figure of girder segments is right, relevant parameters should be calculated and stimulated first according to design data, then every part of the steel box should be adjusted in preframe process, and finally the linear accuracy should be checked.