长距离线路工程投影变形值控制方法分析

Analysis of deformation control on long-distance projection

根据投影变形理论,离坐标原点越远,等距离变形值越大,在长线路工程中,需要充分考虑如何正确选择坐标系统,减少投影变形,提高控制网解算精度.针对某高速公路,介绍了长度投影变形理论,分析线路工程长度变形量与坐标系选择的关系,然后计算出在各种坐标系统下的投影变形值,并对计算结果分析比较,最后提出建立带抵偿高程面的任意带高斯投影坐标系是消除或减少控制网的长度变形更有效的方法.

According to the length deformation theory of the projection, the farther away from the coordinate origin, the greater equidistant deformation values. In a long line project, how to properly select the coordinate system is fully considered to reduce the projection distortion and improve the accuracy of the control network solver .For a highway, the relationship between the length deformation of line project and the choice of coordinate system is analyzed, then the projection distortion value in a variety of coordinate systems is calculated, Finally, arbitrary zone Gaussian projection coordinate system with offset elevation surface is built comparatively, all of which could eliminate or reduce the length deformation of the control network effectively , through the analysis of calculation results.