小半径缓和曲线上预制空心板梁的平面布置计算

以国道G209通道至吉利段改造工程中的双江河大桥设计实例,研究位于小半径缓和曲线上预制空心板梁的外悬臂折线逐步逼近缓和曲线线形,与桥上路线线形一致。具体方法是:采用直角坐标系计算预制空心板斜长、首尾夹角和起终点坐标,根据计算结果与路线线形之差,多次调整空心板梁的梁板宽度和悬臂长度,使外悬臂折线满足路线的缓和曲线线形。研究结果表明,桥上护栏之间的桥面净宽尺寸变化符合设计路线线形要求。

The calculation of plan location of pre-cast hollow slab beams on transition curve of small radius

Based on the design case of Shuangjianghe bridge on the segment from Tongdao to Jili in G209 national highway which was being built,the linear cantilever slabs was made to fit transition curve of the route.The method is as follows: calculating the length,angles and coordinates of pre-cast hollow slab in Cartesian coordinate system,and then adjusting the width of hollow slab beams and length of cantilever boards to make the linear cantilever slabs close to the transition of route.The results show the size between the bridge banisters can meet the need of route design.