ЗНАЧЕНИЕ СИСТЕМНОГО АВТОМАТИЗИРОВАННОГО ПРОЕКТИРОВАНИЯ В СТРОИТЕЛЬСТВЕ АВТОДОРОГ

The rapid process of computer technology improvement that has been developing in recent years has predetermined a qualitative change in both the technology of design and survey work and the design methods. Systematic automated design assumes mandatory multivariance in the development of basic engineering solutions (with automated design, the number of options under consideration is an order of magnitude greater than with traditional technology). This primarily concerns the route plan, the position of the design line of the longitudinal profile, and the structural elements of highways. The volume of initial survey information in this regard increases significantly and, given the tight design deadlines, this information cannot be obtained by traditional methods of survey work using traditional geodetic and engineering-geological equipment. When developing a large number of possible directions of a highway route at the CAD-AD level, information collected on a narrow strip along the a priori accepted direction of the highway is no longer sufficient, and information is needed on a very wide variation strip, where additional route options may pass. This information (topographic, geological, soil and ground, hydrogeological, hydrological) cannot be obtained in a short time using traditional methods of ground surveys [1]. The technology and methods of producing survey work at the CAD-AD level have been widely developed in a number of developed countries. In recent years, the process of restructuring the design and survey business in accordance with the requirements of systematic, automated design of highways and structures on them has essentially been completed in Russia. Distinctive features of producing survey work when designing at the CAD-AD level are: obtaining topographic and other survey information within the route variation strip, the width of which can be up to 1/3 of the route length at the early stages of design, when additional directions of the future road are considered; | widespread use (up to 40-60% of the total volume of survey work) of aerospace methods of collecting information about the terrain: aerial survey, aerogeodetic, aerogeological and aerohydrological; Application of ground-based stereophotogrammetry methods (phototheodolite surveys); Use of electronic digital photography and automated digital photogrammetry systems (ADPS) in photogrammetry for processing stereopairs (e.g. Photomod); Wide application of electronic geodesy methods (Use of electronic total stations, recording levels, light range finders that automatically record measurement results on magnetic storage media in a form suitable for direct input into computer memory); Application of GPS satellite navigation systems in all types of survey work (topographic, engineering-geological, hydrological, economic); Preparation of information in a form suitable for operational use in automated design, i.e. Obtaining digital and mathematical terrain models on the route variation strip; Wide application of geophysical methods in engineering-geological surveys (electromagnetic, seismic, radar, geoacoustic, magnetometric, for gravimetric, nuclear and thermometric methods).

The size of the variation strip of additional route options largely determines both the volumes of aerial and ground surveys and the volumes of design work to find the best route location. Assigning an excessively wide variation strip also leads to an increase in the volume of design and survey work, which greatly complicates the search for the best design solution. If the width of the variation strip is underestimated, there is a risk that the best route option may be outside the zone covered by the survey materials. In this regard, exceptional attention should be paid to justifying the size of the route variation strip. The selected variation strip should cover all areas of the terrain where other road options may pass. The width of the route variation strip is established using topographic maps (usually at scales of 1:25,000—1:10,000), aerial photography materials from previous years, and aerial survey results, taking into account topographic, situational, engineering-geological, hydrogeological, soil-ground, hydrological, and other conditions [2]. Currently, the justification of the variation strip is usually carried out subjectively, without the use of analytical computer methods. In the practice of surveying and designing highways abroad (for example, in the USA, Canada, etc.), great attention is paid to the selection of the route variation strip at the stage of preliminary work. And this is no accident, since with a justified route variation strip, in the course of subsequent design, it is possible to find design solutions whose construction cost is up to 10% lower than the cost of options without a detailed justification of the variation strip, while simultaneously reducing the cost of surveys and design, labor costs, and reducing the time frame for completing design and survey work.

In connection with the transition to the technology and methods of systemic, automated design of highways that has occurred in the country, methods of analytical substantiation of the route variation strip using computer programs are becoming increasingly important. Thus, using existing topographic maps, aerial photography materials from previous years, survey materials carried out at previous design stages, as well as the results of aerial surveys, a preliminary digital model of the terrain is built, which covers a deliberately larger territory than is required to establish the best route direction. Survey materials from previous design stages are especially often used for this purpose, for example, survey materials for a feasibility study to substantiate the variation strip when developing an engineering project. When preparing a preliminary model and analytically determining the boundaries of the variation zone of additional route options, objects and areas of terrain, the passage of the highway route through which is either impractical (valuable agricultural land, swamps, landslides, scree, saline soils, karst areas of terrain) or completely impossible (territories of industrial enterprises, populated areas, territories of defense facilities, protected areas), are immediately excluded from consideration, and fixed points and directions are established, the passage of the route through which is mandatory.