结合高斯投影和抵偿高程面建立GPS控制网

GPS Control Network Establishment by Combining Gauss Projection and Compensation Elevation Surface

高原布设长线路大型工程的GPS控制网时,通常采用高斯投影面的方法来减小边长变形,以满足施工规范要求。针对到高原山区高差大也会导致边长变形超限问题,主要探讨结合高斯投影和设置抵偿高程面的方式。基于实际项目,建立长线路GPS控制网并进行精度评定。通过实测边长与控制点坐标反算边长进行比较分析,论证该方法在山区长线路控制网布设时候有效控制边长投影变形,适用于大高差长距离线路工程。

In view of the long span and long line of GPS control network in highland and mountainous areas,Gaussian projection surface is usu-ally used to reduce the side length deformation to meet the construction specifications requirements.Considering that the high elevation differ-ence in the highland mountainous area will also lead to the edge length deformation exceeding the limit,we mainly discussed the method of com-bining Gaussian projection and setting up the compensation elevation surface,and based on the actual project,established the GPS control net-work for long lines,and evaluated the accuracy.By comparing the measured side lengths with the inverse side lengths calculated from the coordi-nates of control points,it is proved that this method can effectively control the projection deformation of side lengths when the long line control network is laid out in mountainous areas,and it is suitable for long distance line engineering with large height difference.