大气竖直折光系数确定的实验研究

An Experimental Study on Defining the Coefficient of Atmospheric Vertical Refraction

Atmospheric vertical refraction is a key factor affecting the accurancy of exact triangular elevation surveying.It is also a key subject which attracts great attention and interest.The relationship between vertical light refraction and temperature gradient and the application of atmospheric turbu- lence are intruduced in this paper.An experimental study on both subjects has been completed on the campus.From the experiment,the regularity of change of them with seasons and time is obtained, and the result obtained is basically in agreement with the result of theoretical analysis.The authors consider that the common practice of using a definite number(0.14)to calculate k is not satisfactory. In this paper,two sets of surveying results at two hydro-power stations are used to calculate and anal- yse the change of k.The mothed of middle double surveying is put forward.The difference in altitude between double surveying in opposite dinections is small.It is suggested that research should be contin- ued on monitoring network data processing and local light refraction models,so that the accurancy of triangular levellig can be improved,and finally,triangular levelling can be used to replace geodetic levelling.