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Regeneracja bitumicznych nawierzchni drogowych modyfikatorami otrzymywanymi z surowców ekologicznych

Author(s): Michał Babiak,Maria Ratajczak,Jacek Kosno / Language(s): Polish Issue: 4/2016

The production of the mix asphalt with the feedstock of reclaimed asphalt is very popular technology and widely applied in many countries of European Union. The leaders are Netherland, Germany and Denmark. A polish law regulations allows the manufacture the asphalt mixtures with the content of the feedstock of reclaimed asphalt pavement (RAP) up to 30%. The additive of a universal modifier to the reclaimed asphalt will change the rheological parameters of the bituminous binders, increase the adhesion. The manufacture of the mix asphalt with the larger content of the feedstock of reclaimed asphalt pavement will be possible.

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Interpretacja niezgodności spawalniczych w złączu T- joint z podkładką podczas badań ultradźwięk o wych

Author(s): Marcin Górecki,Michał Jordan / Language(s): Polish Issue: 4/2016

One of the most common methods for assessing the welded joints is a nondestructive method using ultrasonic waves. Despite the requirements posed to personnel engaged in research, practice shows that in many cases the incompatibilities in the butt welds in T-joint connections with backing strip are misinterpreted and consequently carry out to unnecessary and costly joints repair. The paper presents the results of tests carried out on samples without incompatibilities, for which the indications of defectoscope suggest the occurrence of apparent defect.

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Próba zastosowania metody elementów dyskretnych w mechanice ciała stałego

Author(s): Tomasz Nowicki / Language(s): Polish Issue: 4/2016

The paper is devoted to Discrete Element Method. Currently the method is mainly used for mechanics of rock. The paper contains the description of the simplest version of the method. Computer simulation using Esys-Particle computer code is presented. The paper is an introduction to the study on the method applications to building engineering.

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Numerical methods in understanding reaction pathways NOx oxidation

Author(s): Justyna Jaroszyńska-Wolińska,Szymon Malinowski / Language(s): English Issue: 3/2016

Different quantum chemical models were applied in energetic analysis of process of oxidation of NO and NO2 through reaction with ozone generated by non-thermal equilibrium (low temperature), atmospheric pressure plasma. The potential energy surfaces of systems comprising NO and NO2 with ozone were characterized. The NOx oxidation processes well known, at the molecular level, were modelled by ab initio quantum methods to calculate the total reaction energy, Et, of each step in the reaction chain. Chemistry was further applied in an attempt to detect the presence of any transition states to calculate the activation energy, Ea, of reactions (1) NO + O3 and (2) NO2 + O3 using the MP2 level of theory with three different basis sets and fine potential energy scan resolution.

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Badania zmian współczynnika filtracji w zależności od wskaźnika porowatości w gruntach słabonośnych

Author(s): Marzena Jaromińska / Language(s): Polish Issue: 3/2016

This paper presents the results of analyses of the simple linear of regression permeability coefficient and void ratio in organic soils. Eight samples of gyttjas coming from the area of Olsztyn were analyzed. The research methodology was described and the e – log k relationship was tested under five loads variants. The linear regression models built on the basis of statistically significant results explained more than 75% variability log k, as it was found as a result of the performed analysis. The high values of F statistics affirm the significance of the linear model. The results indicate that oedometer test procedure does not include many factors contributing to soil permeability properties. The precise identification of the dependence of the filtration coefficient k on the void ratio e is critical in recognizing the mechanism of relationship between these characteristics.

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Ocena preferencji decydenta przy wyborze środków transportowych

Author(s): Artur Duchaczek / Language(s): Polish Issue: 1/2015

In the process of optimizing each criterion validity coefficients allow to take into account individual preferences of the decision maker. They are therefore one of its most important elements of this process. On the Polish market works very diverse range of vehicles. For the calculation of the validity coefficients for the optimization of the choice of means of transport used DEMATEL method. The application presented method resulted in a quantitative consideration of the actual decision-maker preferences based on fairly simple scientific method, and not only the intuition of the decision maker.

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Współczynniki DOP w obserwacjach GNSS*

Author(s): Kamil Maciuk / Language(s): Polish Issue: 1/2015

Integrated GNSS (GPS+GLONASS) satellite measurements carry a number of benefits. The main advantages are especially possibilities of conducting measurements in areas where use of a single satellite system was not impossible so far. In this paper number of visible satellites and DOP coefficients values in terms artificial horizon obstacles were analysed. Paper also discusses benefits of including additional observations from other navigation satellite systems.

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Peculiarities of hydration processes of cements containing natural zeolite

Author(s): Khrystyna Sobol,Taras Markiv,Volodymyr Terlyha,Wojciech Franus / Language(s): English Issue: 1/2015

In this study, properties and peculiarities of hydration processes as well as paste microstructure of blended cements containing 10% by weight of natural zeolite were investigated. Free calcium hydroxide content, crystalline hydration products and microstructural architecture of hydrated cement pastes were examined by physical and chemical methods. It was found that the addition of natural zeolite provides formation of an extra amount of fine crystalline ettringite and tobermorite-like calcium hydrosilicates of CSH (B) type in the mineral non-clinker part of Portland cement resulting in strength synthesis of cement stone with high performance properties.

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Dispatching concrete trucks using simulation method

Author(s): Sławomir Biruk / Language(s): English Issue: 2/2015

Ready mixed concrete (RMC) is the primary material required for buildings and public infrastructure work. RMC is produced to meet customer’s demands and its deliveries must conform to construction site and technological operating constraints – the material cannot be prepared in advance and stored. Concrete production scheduling and truck dispatching is mainly handled manually by experienced RMC batching plants staff. The paper presents simulation model which can be used to asses alternative strategies for truck allocation and production planning in stochastic environment. The models’ operation is illustrated by a notional case – the model prompted solutions of improved transhipment efficiency and reduced plant operating cost under assumed operating constraints.

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Wpływ inwestycji drogowych na zwierzęta – działania minimalizujące

Author(s): Dagmara Nowacka / Language(s): Polish Issue: 1/2014

Poland, which biological diversity stands out in comparison with the rest of Europe, became one of the biggest road construction site during the last few years. A development of a road network almost always involves disturbance of biogically sensitive and protected areas. As those areas cover about one third of the whole country it is virtually impossible to avoid conflicts concerning biological protection. For those reasons, steps to be taken to limit to a minimum the incidence of the construction works on the biological environment constitute an integral part of each investment. The costs of protecting unspoiled environment represent up to 30% of the total costs of investments. The effectiveness of planned actions must consequently justify spending the considerable funds involved. Monitoring of the results of solutions used allows both verification of their usefulness and identification possible errors so that they may be avoided in the future. Number of actions which have been undertaken in Poland to minimalize the incidence of roads on unspoiled environment, in particular as regards the number of fauna passes, to preserve the ecological continuity, place Poland among most advanced European countries.

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Wpływ hałasu drogowego na ptaki

Author(s): Jarosław Wiącek,Maciej Polak,Marek Kucharczyk,Sylwia Zgorzałek / Language(s): Polish Issue: 1/2014

The dynamic development of road infrastructure negatively influences the natural environment and animals using habitats near roads. The main negative effects of this process are primarily: loss and fragmentation of habitats. Another problem is an increase in pollutants and noise intensity in the vicinity of roads. An important problem is negative influence of traffic noise on animals and especially birds. Road noise generate by vehicles disturb vocal communication between birds, mainly in the time of pair formation and early incubation period. Difficulties in communication evoked by noise seem to be one of the main problems in functioning in noisy surroundings. The main functions of birds’ singing are related with territorial defence and mating a partner. Another important effect on birds’ functioning near roads results in the masking of important biological signals due to noise. Masking important signals for territorial defence or partner selection can have as a consequence a negative influence on reproductive success. Species of birds which emit low frequency sounds are particularly exposed to this negative impact. As a results of traffic noise the changes in the volume and frequency of emitted sounds during singing are observed. Some authors pay attention to such factors as local climate or habitat and vegetation structure, because they have an important influence on the propagation of traffic noise. Most of the studies carried out previously concerns the breeding season, and only a few works to describe the impact of noise on birds during migration or wintering. The most frequently reported problem for researchers is to assess the densities of breeding birds near the roadside. The majority of species react with a drop in numbers at roadsides. There are species which are also known to appear with higher density at roadsides. Usually this is related with a richer plant vegetation structure at roadsides and the appearance of the so-called “edge effect”. Some results indicate that bird density at forest peripheries can reach values 40% higher than in the deep forest. An explanation of causes for such a state of matters are the higher numbers of invertebrates found at forest edges. The important factor influencing bird populations breeding at roadsides is also nest predation. Noise and visual disturbance can modifying predator pressure near roads.

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Działania prośrodowiskowe podejmowane we Francji na etapie eksploatacji autostrad

Author(s): Agnieszka Bugajska,Andrzej Kulig / Language(s): Polish Issue: 1/2014

Road investments, including motorways and expressways, are among the projects which can have a significant impact on the environment. For this reason the proper evaluation of this impact is required, as well as its effective elimination, mitigation or compensation. The impact of the project on the environment can be observed already during the construction stage, and then sometimes on an even larger scale during the operation stage of the road infrastructure. Therefore, a proper ex‑post evaluation of the real impact of such projects is a very important and indispensable part of the process of environmental impact assessment (EIA). It enables taking corrective actions or ensuring effective operation of environmental protection equipment. Road operators can also take many other pro-environmental actions to reduce the impact of these investments on the environment. Thanks to its extensive road network and long-established legal requirements and official methodical guidance, France has an important experience in the field of realization of mandatory environmental ex‑post evaluation reports, as well as in implementing multiple other projects regarding the protection of the environment that do not arise from legal obligations. The paper presents examples of good practices and pro-environmental actions undertaken during the operation stage of certain motorways in France. These actions contribute to better integration of the motorways with the surrounding area and often combine environmental and socio-economic aspects supporting the principle of sustainable development.

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Wpływ zagospodarowania terenu na rozkład poziomu hałasu drogowego na powierzchni górnych przejść habitatowych

Author(s): Alicja Sołowczuk / Language(s): Polish Issue: 1/2014

The Environmental Protection concerns mainly the fauna, because the development of communication and the construction of new transport routes has been increasingly fragmenting the natural environment. To fix the errors, arising from the fragmentation of the natural environment, upper or lower crossings are built for animals. The upper crossings are very expensive because of their dimensions. The construction of the upper crossings does not always turn out to be functional, as badly developed surfaces are not attractive to animals, which do not use them. The proper management of the upper crossings area is a very difficult issue, still quite experimental. In the literature, no functional solutions can be found in this regard. The only guidelines for designers may be the examples of the area development of the existing crossings, whose functionality was confirmed by the data from monitoring. However, ready solutions from other roads and natural conditions are not always useful, because in most cases the crossings should be tailored to the wildlife which use them. The paper presents various development elements, together with the results of noise analyzes, confirming the impact of the development, depending on its type, on the ”achieved status of soundproofness” on the access to the crossings and their surface.

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Hałas od ruchu samochodowego w otoczeniu skrzyżowań

Author(s): Marek Motylewicz,Władysław Gardziejczyk / Language(s): Polish Issue: 1/2014

Over the period of the last few years special attention has been paid to the issue of protecting built-up areas against excessive traffic noise. Prediction and assessment of the level of noise in areas surrounding intersections was of primary interest to the researchers. Studies in this field have been carried out in numerous research centers in Poland and around the world. Existing noise prediction models describe the noise level in areas close to intersections with different degree of accuracy, depending on the number and type of factors included in the model. The paper presents the results of studies on the equivalent noise level in the surroundings of various types of intersections. It shows the impact of the following factors on traffic noise: geometry, traffic organization, traffic composition and distribution as well as the distance from the intersection. It was stated that apart from the basic traffic parameters (intensity and composition) and the characteristics of entries, some factors, including intersection geometry, organization and management of traffic and the traffic conditions should be analysed in greater detail.

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Zalecenia projektowania, budowy i utrzymania przejść dla zwierząt - dokument ujednolicający problematykę

Author(s): Adam Wysokowski / Language(s): Polish Issue: 1/2014

With the sustainable development of transport infrastructure can not ignore the environmental problems. This applies both to build much-needed new roads and railways, as well, as their modernization. For this purpose, it becomes essential to build passages for animals and culverts of complex function. The author of the paper moves the need for a unified Recommendations of Design, Construction and Maintenance of Animal Passages, which clearly organize all the issues associated with these objects. Currently such recommendations are being developed under the leadership of the author.

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Warunki zastosowania popiołu lotnego jako wypełniacza do mieszanek mineralno – asfaltowych

Author(s): Wojciech Grabowski,Jarosław Wilanowicz,Marta Andrzejczak,Marcin Bilski / Language(s): Polish Issue: 1/2014

The main purpose of this work is to get to know the structural and functional properties of fly ashes, i.e. industrial waste from lignite-fired power plant, from the perspective of their use as fillers for hot-mix asphalt (HMA). Analysis of the results of laboratory tests: grain-size distribution, specific surface, air voids of dry compacted fillers, stiffening properties in bituminous mastics showed that the fly ashes do not meet the requirements for fillers to HMA, because they cause too much stiffening impact. The results of extensive research has shown that these ashes can be used for the HMA, as so-called the mixed fillers with the participation of limestone filler used traditionally.

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Zastosowanie ANFIS w analizie wyników badan gruntów

Author(s): Ewa Daniszewska / Language(s): Polish Issue: 2/2014

The article was analyzed in order to test applicability and capability of the ANFIS tool used for interpretation of results of triaxial shear tests on loamy soils sampled near Olsztyn. The ANFIS system in the Matlab software programme was used to model and determine relationships between the shear stress and soil resistance parameters in a triaxial shear test apparatus. It has been demonstrated that the achieved shear strength parameters are significantly affected by the variables tested during the triaxial experiments and physical parameters of a given soil sample, but also by the loading increment rate during the tests. It is extremely important to adjust the rate of loading during a test according to the preliminary characterization of a tested ground sample so as to have some control over the obtained ground strength parameters. The neuro-fuzzy model has been constructed based on a set of values obtained after a series of experimental tests, including values of ground shear strength parameters. The database used for the neuro-fuzzy modelling consisted of 6 different ground parameters for each of the 12 shear stress rates applied during the triaxial tests. The learnability was verified on a database composed of the test results – a neuro-fuzzy model was built from learning sets and its accuracy was verified by sets of tests to which the model was applied for the first time. The results obtained from the ANFIS model did not diverge substantially from the ones obtained directly by performing the physical tests. The ANFIS proved to be highly universal and easy to operate. It accounted for the multi-faceted nature of interrelationships between ground parameters.

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Zarządzanie bezpieczeństwem istniejącej sieci drogowej

Author(s): Marcin Budzyński,Kazimierz Jamroz / Language(s): Polish Issue: 4/2014

The objective of road infrastructure safety management is to ensure that when roads are planned, designed, built and used traffic accident risks can be identified, assessed and mitigated. There is a number of approaches, methods and tools for road safety infrastructure management. European Union Directive 2008/96/EC regulates and proposes a list of tools for managing road infrastructure safety. The paper presents two of these tools - classification of dangerous sections and control of the infrastructure in the field of safety. The final section presents the necessary directions for further action, particularly scientific research, supporting the management of the existing road infrastructure.

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Analiza właściwości asfaltu spienionego 50/70 w aspekcie przydatności do mieszanek mineralno-asfaltowych

Author(s): Anna Chomicz-Kowalska / Language(s): Polish Issue: 4/2014

The aim of the study was to analyze the properties of foamed bitumen produced from 50/70 bitumen in terms of the assessment of its usefulness to the road construction materials. In order to improve the foaming parameters the synthetic wax Fischer-Tropsch (FT) in an amount of 1.0%, 2.0% and 3.0% was used. Bitumen binder parameters were evaluated before and after the foaming process. The basic parameters were evaluated (before the foaming process): penetration, Fraass breaking point and softening point. The bitumen foam parameters were measured at the foaming water content (FWC) in the range from 1.5% to 4.0% with an increment of 0.5%. The tests allowed determining optimal application ranges for the FT and the FWC to produce asphalt at lower temperatures.

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Wtórne wiązanie kruszywa z recyklingu betonu na przykładzie badan materiału i warstw podbudowy konstrukcji nawierzchni drogowej

Author(s): Jakub Fengier,Andrzej Pożarycki / Language(s): Polish Issue: 4/2014

The work is an attempt to summarize the experience concerning the diagnosis of the practical properties of recycled aggregate concrete cement (RCA). It describes the phenomenon of self-cementing properties which was investigated in both the laboratory and on field tests including compressive strength of RCA, non-conventional oedometric tests of RCA and plate bearing tests on the surface of RCA layer. The described self-cementing properties were remarked, however, the RCA material was characterized by smaller increase in the value of parameter EV2 in a 2-year period of time than recycled concrete materials described in the available literature.

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