大型城市立交桥线型计算

Calculations of the alignment of large urban overpass

利用直角坐标系下线路的参数方程，配合坐标变换原理，解决了大型城市立交桥线型计算的有关问题，如曲线交卢、经纬距计算、偏角计算．线路两侧指定部位坐标计算、弯梁边缘线长度计算等．

The article advances a way to solve the problems about the calculations of thealignment of a large urban overpass such as calculations of the coordinates of the crossingpoint between two curves and of a specified point by the road sides, calculation of the curvedeflection angle, and calculation of the lengths of the edge lines of a curve beam. The calculations use the parameter equation of the road alignment in a rectilinear coordinate systemand the principle of coordinate conversion.