Evaluating the accuracy of determining the points’ position by free stationing method

The accuracy of determining the points’ position through the free stationing method is estimated. At performing alignment work, surveying facades, executive surveys, and geodetic monitoring of buildings and structures, the method of free stationing with an electronic total station installed in any suitable place and determining its position by serif, and then using the polar method, defi ning the coordinates of the determined point is considered. The accuracy assessment is identifi ed using the formulas of calculating the mean square error for the direct and reverse angular serifs, as well as for linear ones. The authors propose algorithms of accuracy evaluation for the located point positions with non-fi xed stationing method based on the parametric adjustment, and searching ones, at the same time the algorithms shall provide adjustment by considering or ignoring the errors in the input data. To determine the mean square error of the standing point’s position and the determined points according to the results of adjustment by the free stationing method, fi eld experimental studies were carried out. Numerical examples of accuracy evaluation are provided. The compliance of the adjustment results and root-mean-square errors will mean the validity of the proposed algorithms and accuracy of the performed survey.

Analysis of Deformations of the Skylight Construction at the Main Hall of the Warsaw University of Technology

The paper presents technology and results of measurements of the steel construction of the skylight of the Main Hall of the Warsaw University of Technology. The new version of the automated measuring system has been used for measurements. This system is based on Leica TCRP1201+ total station and the TCcalc1200 software application, developed by the author, which operates on a laptop computer connected with the total station by the wire. Two test measurements were performed. Each of them consisted of cyclic measurement using the polar method, from one station; points located on the skylight construction, as well as control points located on concrete, bearing poles, were successively measured. Besides geometrical values (such as Hz, V angles and the slope distance D), the changes of temperature and atmospheric pressure, were also recorded. Processed results of measurements contained information concerning the behaviour of the skylight; asymmetry of horizontal displacements with respect to the X axis have been proved. Changes of parameters of the instrument telescope and changes of the instrument orientation were also stated; they were connected with changes of the temperature. The most important results of works have been presented in the form of diagrams.

MEASUREMENT OF VERTICALITY CONSTRUCTION OF BUSHINGS FOR LABORATORY CONSTRUCTION MATERIALS

This contribution describes process which was used for verticality measurement of the bushings for laboratory construction materials in the pavilion of testing. This pavilion is newly built in VŠB-TU Ostrava, Faculty of Civil Engineering, as part of the Testing house of the building materials. The requirement of the building investor was to determine the verticality of the bushings placed between the first aboveground and the first underground floor. After the building finishing, the bushings with the diameter 70 mm will be used for loading tests of various building materials. The final number of bushings is 169, and they are placed lengthwise and crosswise in the step of 750 mm. The centres of the bushings were measured by polar method in pavilion local coordinate system. The precision of the bushing centres determination was }5 mm according to the investor´s requirement. The precision would not be followed if the standard equipment for reflector fixing was used. In that case, it was necessary to design and manufacture special tool in the shape of truncated cone. On the top part was placed central pivot for reflector with additional plate bubble.

Verticality Determining Methodology for the Reconstruction of a Building Shell – Analytical Solution

The paper presents surveying and processing procedures used at a reconstruction of a circumferential jacket of a 13-storey building, as well as possibilities of numeric and graphic presentation of measurement results. The suitability of specific used procedures depends mainly on the dimensions of the building and its space zoning. Usually, the space polar method is commonly used for surveying of mediating parameters. Analytic processing is considered to be the most suitable method of evaluation of measured point deviations from the vertical plane, or from the plane in general position, mainly because of its smartness, rapidity and universality.