结合井口对称点的竖井联系测量的应用OA

It is difficult to orientate in vertical shaft connection survey.The influences of vertical axis tilt error,projection error and centering error on horizontal angle can be weakened by wellhead symmetrical points.It is proposed to arrange symmetrical points on wellhead to establish a starting or ending direction for a traverse in tunnel.For two shaft orientation,the check condition for horizontal angles can be added for non directional traverse.Combined with a tunnel expansion project,the effectiveness of the method was verified.The method can be used for one vertical shaft orientation on the basis of other methods,more accurate orientation azimuth can be determined.It can also be used as a reference for two shaft orientation.