特大型桥梁投影面的选择方法研究

Research on Selection Method for Projective Plane of Extra Large Bridge

桥梁施工建设时控制网投影面选取关系到全桥施工的定位精度,针对特大型桥梁线路长、施工精度要求高、投影不可避免存在变形等特点,提出利用任意投影带的高斯正形投影,对桥梁的各部分按照结构重要性划分投影变形权重,求出使得全桥GPS控制网长度综合变形最小的、符合施工精度要求的、全桥统一的最优抵偿投影面。

The selection of construction control network＇s projective plane has relation to the positioning accuracy when bridges are constructed.According to the characteristics of extra large bridges such as long lines,high construction precision and unavoidable distortion of projection,the method is put forward here which would use the Gaussian orthogonal projection of any projection belt and divide the distortion weight of projection according to the importance of structure in order to obtain the projective plane which could make the comprehensive deformation of the whole bridge＇s control network smallest.This method could not only meet the requirements of construction accuracy,but also make the whole bridge＇s projective plane unified and optimized.