| 摘要 |
PURPOSE: To improve the unstable state of an erected arch and the difficulty of the execution of works at the time of a large span at the time of the erection of the steel-pipe arch through a lowering method. CONSTITUTION: An arch span is divided into the four in total of two base section arches 10, 20 and two end section arches 11, 21, and members obtained by folding and bonding the base section arches and the end section arches are disposed in upright on bearing abutments 13, 23 on both banks respectively. The members are tilted, the end section arches are elongated and brought to the state of half arches respectively, and these arches are joined in arch crown sections. |
