Abstract: In the construction of big type bridge. require higher precision of pier shaft construction survey. the paper about precision of polar coordinates method setting out pier shaft mould board and precision of the EDM trigonometric leveling method carry through pier tip height control and positioning pr ecision of pier axis as well as needed precision of pass control point of bridge axis carry through accuracy analysis and discuss.

Key words: polar coordinates method setting-out, pass control net, the EDM trigonometric leveling , coordinate transformation;accuracy analysis

摘要： 在大型桥梁施工中,墩身的施工测量精度要求较高,本文就墩身施工测量中的极坐标法放样墩身模板的精度及测距三角高程法进行墩顶高程控制的精度、墩身轴线的定位精度以及对桥轴线加密控制网点的必要精度进行了精度分析与探讨.

关键词: 极坐标放样, 加密控制网, 测距三角高程, 坐标转换, 精度分析