全站仪中间法三角高程测量精度分析及应用研究

通过电磁波测距三角高程测量建立高程控制网,可以大大提升野外测量效率。在三角高程测量基本原理的基础上,为消除仪器高、目标高量取等误差,进一步提高测量精度和应用领域,本文分析了高精度全站仪中间自由设站法三角高程测量的工作原理,根据误差传播定律推导了高程测量误差传播公式,分析了测距误差、测角误差和大气折光系数误差对高差测量精度的影响。通过实验数据,证明在适当控制视距和竖直角大小的情况下,其测量精度可以有条件地达到二等水准测量精度。在我国高速铁路建设中,该方法广泛应用于桥下水准基点、桥上CPⅢ控制点之间的高程传递,操作灵活方便,降低了外业劳动强度,取得了良好的效果。伴随全站仪精度和可靠性的不断提升,该方法应用前景广阔。

Accuracy Analysis and Application of Trigonometric Leveling Using Total Station Intermediate Method

Establishing elevation control network by electromagnetic wave ranging trigonometric leveling can greatly improve the efficiency of field survey. On the basis of the basic principle of trigonometric leveling,in order to eliminate the errors of instrument height and target height,and further improve the measurement accuracy and application fields,this paper analyses the working principle of trigonometric leveling with high precision total station set-up freely in the middle,deduces the error propagation formula of elevation measurement according to the law of error propagation,and analyses the ranging error,angle measurement error and atmospheric refraction. Through the experimental data,it is proved that the measurement accuracy can reach the second-class leveling accuracy under the condition of controlling the visual distance and the vertical angle properly.In the construction of China’s high-speed railway,this method is widely used in the elevation transfer between the benchmark base point under the bridge and the CPIII control point on the bridge. It is flexible and convenient to operate,reduces the intensity of field work and achieves good results. With the improvement of accuracy and reliability of total station,this method has broad application prospects.