Optimal Location of Extra Gyroscopic Azimuth in Underground Traverses

In traditional underground surveying operations, where a bearing is transferred through a single shaft, only one azimuth of the underground traverse is involved. The use of gyroscopic measuring equipment, however, allows the direct determination of the azimuth of other sides of traverse. Measurement of an extra gyroscopic azimuth allows not only checking the observations of the azimuths and the angles between them, but also reduces the breakthrough error. Determination of the optimal location of an extra gyroscopic azimuth in straight traverse with the sides of the same length assures minimal influence of errors of measurements in the traverse on the value of the lateral component of the breakthrough. In this paper the problem of optimal location for an extra gyroscopic azimuth in straight tunnel construction, in which there is a straight traverse with the sides of the same length, is solved. Analysis of the accuracy effects as well as numerical examples indicate definite advantages in application of optimal technology as compared with measuring extra gyroscopic azimuths in other places. In this work it is also stated that the optimal location of an extra gyroscopic azimuth in straight traverses having sides of the same length is in the third part of the traverse, independent of the accuracy of measurement.