In the field of spatial management, especially from the point of view of spatial economics, many decisions have long-term effects on the environment. Therefore, it is essential that the boundary ...conditions of the decision-making process are not only transparent, but also aligned with the sustainable development goals. At the same time, road infrastructure represents one of the most complex linear structures in the area, and its comprehensive management should respond to various types of problems, from structured to unstructured, which occur at all levels of decision-making. To solve such problems, management information systems (UIS) can help decision-makers to apply appropriate models and methods during the decision-making process. This paper provides an overview of the different types of UIS that can be used in road infrastructure management. The method of selecting an appropriate UIS and the method of interaction between data and models in such a management system are also discussed.
U pogledu upravljanja prostorom, naročito s aspekta prostorne ekonomije, mnoge odluke koje se pritom donose imaju dugoročne utjecaje na okoliš. Stoga se kao imperativ nameće da rubni uvjeti procesa donošenja odluka budu, ne samo transparentni, već i usklađeni s ciljevima održivog razvoja. Pritom cestovna infrastruktura predstavlja jednu od najsloženijih linijskih građevina u prostoru čije bi cjelovito upravljanje trebalo imati rješenje za najrazličitije tipove problema, od strukturiranih do nestrukturiranih, koji se javljaju na svim razinama odlučivanja. U cilju rješavanja takvih problema upravljački informacijski sustavi (UIS) mogu donositeljima odluka pomoći da primijene odgovarajuće modele i metode tijekom procesa donošenja odluka. U radu je dan pregled različitih tipova UIS-a koji se mogu primijeniti i koristiti u gospodarenju cestovne infrastrukture. Također, u radu se diskutira o načinu odabira primjerenog UIS-a kao i načinu interakcije između podataka i modela u jednom takvom upravljačkom sustavu.
Ocjena strukturalnog stanja kolnika definira ukupnu nosivost kolnika, a određuje se kroz ocjenu mehaničkih svojstava slojeva kolničke konstrukcije. Defleksija predstavlja elastičnu deformaciju ...kolničke konstrukcije i jedan je od važnih pokazatelja strukturalne nosivosti kolnika. Iznos defleksije moguće je utvrditi teorijski, korištenjem zakonitosti teorije elastičnosti i poznavanjem materijalnih svojstava kolničke konstrukcije, ili empirijski, mjerenjem elastične deformacije generirane poznatim statičkim ili dinamičkim opterećenjem na površini kolnika, najčešće korištenjem uređaja s padajućim teretom (FWD uređaj). U ovom radu opisane su teorijske metode za određivanje strukturalne nosivosti kolničke konstrukcije, s naglaskom na defleksiju kao prevladavajući tehnički parametar za utvrđivanje ocjene strukturalnog stanja kolnika. Opisan je empirijski postupak utvrđivanja defleksije FWD uređajem te je dan pregled utjecajnih činitelja na izmjerene iznose defleksije. Prikazani su indeksi proizašli iz mjerenja defleksije, koji se koriste za utvrđivanje strukturalne ocjene kolnika. Na primjeru analize stanja kolničke konstrukcije provedene u sklopu diplomskog rada prikazana je važnost provedbe kontinuiranog mjerenja u svrhu utvrđivanja strukturalnog stanja i ocjene kolničke konstrukcije.
The assessment of pavement structural condition defines the total bearing capacity of the pavement, and is determined through the assessment of the mechanical properties of pavement structure layers. Deflection of the pavement structure is one of the important indicators of the structural bearing capacity of the pavement. It represents the elastic deformation of the pavement structure and is inversely proportional to the bearing capacity of the pavement. The amount of deflection can be determined theoretically, by using the laws of the theory of elasticity and knowing the material properties of the pavement structure, or empirically, by measuring the elastic deformation generated by a known static or dynamic load on the pavement surface, usually using a falling weight deflectometer device (FWD device). This paper describes the theoretical methods for determining the structural bearing capacity of pavement structure, with emphasis on deflection as the predominant technical parameter for determining the assessment of pavement structural condition. An empirical procedure for determining deflection and an overview of influencing factors on the measured amounts of deflection are described. The indices derived from the deflection measurements used to determine the structural assessment of the pavement are presented. On the example of the pavement structure condition analysis, carried out as part of the master thesis, the importance of the implementation of continuous measurement in order to determine the structural condition and assessment of the pavement structure is shown.
Analyses of urban pavement surface temperatures Deluka-Tibljas, Aleksandra; Surdonja, Sanja; Babic, Sergije ...
The Baltic journal of road and bridge engineering,
09/2015, Letnik:
10, Številka:
3
Journal Article
Recenzirano
Odprti dostop
Heat islands are areas that have higher air temperatures than their surroundings. It has been proven that the use of certain types of pavement surface materials contributes to the occurrence of heat ...islands. The heat island effect is dominant in urban areas, mainly in city centres. To identify potentially favourable pavement surface materials that are suitable for the use on surfaces in urban areas, an extensive analysis of in-place material temperatures was conducted in the city centre of Rijeka (Croatia) during the summer of 2011 and 2012. The measurements included temperatures of pavement surfaces made of asphalt, concrete and stone. The analysis results identified local materials whose use help to reduce or mitigate the effect of additional heating in the urban environment caused by emission of heat from pavement surfaces. In terms of additional heating of urbanized areas, asphalt has proven to be significantly less favourable than other analysed materials. In addition to the materials selected for the use in wearing courses, their characteristics and the microclimates of the locations where they will be placed must be taken into consideration. Among the standard paving materials, in terms of heating and temperature, concrete is more favourable than asphalt because the differences between concrete surface temperatures and air temperatures are significantly smaller than between asphalt surface temperatures and air temperatures. Stone surfaces have proven to be the most favourable. The analysis results presented can be used to establish clear guidelines for using specific materials under specific conditions.
Pavement skid resistance is one of determining road features that contributes to traffic safety. Several influencing factors govern the skid resistance, amongst which the pavement surface texture is ...the one that could be designed and controlled by the pavement engineers. Pavement surface texture is classified into four categories, where microtexture and macrotexture level affect the pavement skid resistance. Microtexture contributes to skid resistance at low traffic speed, while macrotexture governs skid resistance at high speed. Macrotexture is a result of asphalt mixture properties, mostly the aggregate gradation, maximum aggregate size, binder and air voids content. Macrotexture is usually measured using different volumetric or optical devices, and the measuring results are expressed as texture depth or profile depth values. Several studies showed that macrotexture level can be correlated to pavement skid resistance performance. Previously conducted small-scale case study performed on road network in City of Rijeka analyzed the influence of pavement surface renewal treatment on macrotexture values increase and its influence on skid resistance values. In this paper, an analysis of measured macrotexture and skid resistance values is shown for a greater set of data. The measurements were conducted on selected highway section in Croatia, using laser profilometer for macrotexture determination and surface friction trailer for skid resistance determination. Both pavement surface performance indicators – Mean profile depth (MPD) for the macrotexture and longitudinal friction coefficient (LFC) for the skid resistance were measured before and after the renewal treatment in order to determine the influence of the renewal treatment on the surface performance improvement. The measured values were then correlated, showing that skid resistance is connected to the level of pavement surface macrotexture.
Heat islands are areas in which temperature is higher than that prevailing in surrounding areas. They are dominantly formed in developed urban zones, and are further intensified by the use of ...pavement structures with poor thermal properties. Results obtained during temperature testing conducted on pavements of various types and properties are presented in the paper. The measurements were made in summer months of 2011 in the town of Rijeka. The analysis of results has revealed new data about sensitivity to heating of individual types of pavement structures, and about behaviour of various types of surfacing when subjected to similar heating conditions.
Stanje prometnih površina degradira se uslijed klimatskih i meteoroloških uvjeta, prometnog opterećenja i nedovoljnog održavanja. Unutar gradske prometne mreže autobusne postaje su zbog specifičnog ...opterećenja osobito podložne prijevremenoj pojavi oštećenja. U radu je prikazana analiza stanja kolničkih konstrukcija autobusnih stajališta provedena u gradu Rijeci. Provedena su mjerenja i analize za više parametara što je rezultiralo preporukama za obnavljanje analiziranih kolničkih konstrukcija.
Some elements for assessing the radiated heat in urban areas Kozar, Ivica; Pesa, Kresimir; Cuculic, Marijana ...
2020 43rd International Convention on Information, Communication and Electronic Technology (MIPRO),
2020-Sept.-28
Conference Proceeding
Heat island describes increase in air temperature between a city and its surrounding area. The air temperature increase significantly endangers the quality and health of life in a city. Radiation ...plays a crucial role in heating of open surfaces in a town. Solar radiation heats the surface that later cools itself radiating heat during the night. The presented model calculates the amount of daily sunlight for arbitrary location and arbitrary day of year. This is the basis for calculation of shades from buildings and estimation of the heat radiated to the street. This is an input for the second part of the model: calculation of the street surface temperature and heat exchange with the surrounding air. Heat exchange problems involving radiation lead to a non-linear formulation, which can be simplified with careful parameterisation, i.e., contribution of radiation should be expressed through radiated heat instead of direct influence of distant body temperature. That approach requires introduction of a non-linear convective heat transfer coefficient between the pavement and the open air. In order to determine model parameters, small experimental field with several differently paved areas has been established near the Faculty. Some of the recorded data is presented in the paper.
Toplinski otoci su područja na kojima je temperatura viša od one u okolnom području. Nastaju uglavnom na izgrađenim površinama gradova, a doprinosi im i uporaba kolničkih konstrukcija koje imaju ...nepovoljnija toplinska svojstva. U radu su predstavljeni rezultati ispitivanja temperature različitih vrsta i svojstava kolničkih površna. Mjerenja su provedena tijekom ljetnih mjeseci 2011. u gradu Rijeci. Analizom rezultata je utvrđena osjetljivost pojedinog tipa kolničke površine na zagrijavanje kao i ponašanje različitih tipova površina u istim uvjetima zagrijavanja.
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