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H. Kahmen:
"High Precision Positioning and Navigation for Industrial Production Processes";
Distinguished International Lecturers Series ENGO 699.81, Calgary, 2002, 81 S.

Surveys in connection with planning, staking, and monitoring of technical objects often require that the surveyor cooperates and is in direct contact with engineers of other disciplines. Such projects require not only solid knowledge and experience in all aspects of practical and theoretical surveying, geodesy and associated subjects, but also sufficient understanding of structural methods and of machinery as well as knowledge of fundamental physics.

The field of engineering surveys has been growing significantly in recent years. The surveying engineer is nowadays not only involved in railway, highway and hydrological projects, but also when locating energy distribution systems, erecting large buildings, setting up and aligning machines, mounting structures from prefabricated parts, building towers, adjusting antennas, etc. Accuracies in position and height of mm for distances of up to 1 km may be required, e. g., when staking an electron accelerator.

Frequently, today, classical staking is replaced by navigation of construction machines. Normally then navigation is based on geodetic methodes.

A surveying engineer faces three different tasks with each project.

1) Mapping of the local conditions as the basis for preliminary and final design.
2) Transfer of the final design into the field and checking of completed sections of the project.
3) Monitoring of the structure and its effect on surrounding areas for horizontal and vertical movements during construction and afterwards.

Generally, the civil engineer expects from the surveying engineer reliable numerical data, which can be directly utilised in further design considerations. The surveying engineer has to keep up with the constructions progress and the tempo dictated by the use of modern machines. Furthermore, he must be versed in highly precise measuring methods, e. g., during bridge construction, tunneling, etc.

These demands force the surveying engineer to use photogrammetric methods, EDM instruments, recording theodolites, as well as special instrumentation, such as plummets, gyro theodolites, lasers and, of course, electronic computers. The latter used to take over repetitive computation, but have long become vital for actual design work, which means that the surveying data have been integrated into the design. The surveying engineer, therefore, has to utilise measuring methods which are economical.

With the aid of error theory and mathematical statistics, he has to determine which measuring accuracy is appropriate for a given construction phase. For this, he must know specifications and tolerances which he often obtains on site only when discussing it with the engineer of the respective discipline. He also has to forcefully insist on measuring efforts which he considers necessary to meet these specifications.

Of the three types of jobs, namely topographic survey, staking, and monitoring, the survey does not generally differ too much from the methods of detail surveys and topographic mapping. Instrumental errors and projection distortions rarely need to be considered because most of them are eliminated by the observation and computation methods.

When staking and monitoring, however, sometimes the surveying engineer not only utilises the already mentioned new approaches, but occasionally has to resort to totally unconventional methods. Furthermore, he has to always consider the effects of instrumental errors and of projection distortions as well as, in some cases (e. g., tunnelling), the influences of refraction and of the deflection of the vertical.

Thus, the surveying engineer needs to be well versed in practical surveying as well as in the geodetic sciences. Thus, engineering surveying is not a specific area like photogrammetry but rather is the application of the whole field of surveying engineering under difficult circumstances.

It is thus only possible to present a limited selection of examples for the rapidly growing area of engineering surveying.