Milivoj Vulić

The Usability of Terrestrial 3D Laser Scanning Technology for Tunnel Clearance Analysis Application

After building underground constructions, spatial parameters monitoring is essential due to safety and statuary reasons. Therefore after completion of work in tunnels often supervision projects follow which include cross sections measurements, as well as ground and secondary wall layer deformations monitoring during consolidation era. Conventional approaches to achieve this type of documentations are different, however their downside is often that they are time consuming and even with combination of independent contractors, collected data is often deficient and corrupted with rough interpolations. Terrestrial 3D laser scanning (TLS) represents alternative approach to conventional monitoring methods [1]. With engineer planning approach, field work and data interpretation, TLS technology allows systematical and fast acquisition of shape and spatial orientation of complex objects and all their components. In case of shorter railway tunnels (up to 360 m) data for clearance analysis in correlation of standard cargo and tunnel surface, was captured with terrestrial 3D laser scanning method. Control of tunnel clearance is usually performed analogously and on conventional low equidistant cross section survey method. Considering that in this article we deal with relative old tunnels, in which there is no constant transversal profile but huge amount of geometric anomalies, simulation verification could be performed only with hi-grid definition survey method. With TLS larger amount of tunnels were measured and clearance analysis simulations for real case of standard cargo profile was made, based on radius and railway inclination of the tunnel. Standard or non-standard cargo transport planning with computer simulation now can be done in relatively short time. In this article is presented integration of TLS in case study of short railway tunnels with focus on clearance analysis applications with interactive and user friendly visualization for data interpretation. Other methods for different spatial parameters interpretations in underground constructions are presented as well.

Optimalna kartografska konična projekcija – analiza slučaja za geografski teritorij Srbije

Original scientific paper The article deals with finding the optimal map conic projection which, according to the criteria of the minimum of distortions, would be more appropriate than the available and, up to the present point in time, generally used conic map projections. Apart from the best map projection, the paper also describes other conic projections still used in the official cartography of Serbia. In the paper, the size of the deformations is analysed and shown in case of the Modified polyconic projection and the Lambert conic projection on the example of a geographical map at scale 1:1000 000. Namely, the size of the linear deformations is analysed and shown in all cases. One of them, the fifth example of the Lambert conformal conic projection, is the most favourable in terms of size and distribution of the deformations upon the entire surface of mapping. Examples of real conformal conic projections are made with numerical procedures in the program package MATLAB.

Affordable Photogrammetry as Applied in the 3D Modelling and Monitoring of Underground Mining Exploitation and Transport

The application of photogrammetry, with a particular emphasis on 3D modelling and monitoring, is of interest in the field of underground mining transportation. In the article, a practical assignment concerning the creation of a 3D model with the aid of an ordinary photographic camera and a personal computer, practically conducted by a student with the aid or supervision of a lecturer at the University of Ljubljana, Slovenia, as a part of the academic process that is, in the effort to instil practical knowledge into students, part of pursuing a mining degree, is described in detail, delineating all the procedures involved, any appearing problems, the means to deal with any appearing problems and the means to employ the obtained 3D model in the future. The aim of creating the 3D model was to demonstrate the convenience of applying photogrammetry in the fields of mining, geology and geotechnology, as well as to introduce a tool that is, in terms of its efficiency, relatively poorly represented in Slovenia and, taking into account its affordability along with its efficiency, to consider its practical application in the mining, geological and geotechnological professions.

Parametric adjustment of a junction triangle in terms of the precise construction of haulage drives in underground mines

In total costs of ore mining, haulage participates with 30-60%; the total number of workers engaged in the transportation exceeds 35%, while the participation of transportation in the total power consumption amounts to over 40%. All these values indicate that transportation is one of the most signifi cant challenges in the underground mining of ore deposits and that haulage analysis is very important both in selecting the haulage type and its design, utilization and maintenance. In addition to various technical mining parameters, together with mining and geological conditions, haulage effi ciency depends on the selection of optimal haulage drives, which can be achieved by accurately connecting the underground mine workings with mine network points on the surface of a site. The selection of the best mine haulage routes is one the most critical tasks in mine surveying. This paper shows how to adjust a junction triangle on a working level using the parametric adjustment method.