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Search results for: TYRE ROAD/NOISE
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Assessing Highway Travel Time Reliability using Probe Vehicle Data
PublicationProbe vehicle data (also known as “floating car data”) can be used to analyze travel time reliability of an existing road corridor in order to determine where, when, and how often traffic congestion occurs at particular road segments. The aim of the study is to find the best reliability performance measures for assessing congestion frequency and severity based on probe data. Pilot surveys conducted on A2 motorway in Poland confirm...
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Optimum Choice of Randomly Oriented Carbon Nanotube Networks for UV-Assisted Gas Sensing Applications
PublicationWe investigated the noise and photoresponse characteristics of various optical transparencies of nanotube networks to identify an optimal randomly oriented network of carbon nanotube (CNT)-based devices for UV-assisted gas sensing applications. Our investigation reveals that all of the studied devices demonstrate negative photoconductivity upon exposure to UV light. Our studies confirm the effect of UV irradiation on the electrical...
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On analysis of double-impact test of 1500-kg vehicle into w-beam guardrail system
PublicationEvery day on roads many scenarios of accidents may occur. One of the measures to minimize their consequences is road safety barriers. Finite Element analyses are being increasingly used to support the physical testing of these devices. The paper addresses the issue of a secondary impact into the previously damaged w-beam guardrail system. This situation belongs to one of the most dangerous which can happen on roads and may cause...
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TEMPERATURE INFLUENCE ON TIRE ROLLING RESISTANCE MEASUREMENTS QUALITY
PublicationGlobal warming makes it necessary to reduce energy consumption, which in the case of motor vehicles, is connected, among other things, with reduction of resistive forces acting on a vehicle during its motion. One of the most important components of those forces is rolling resistance, which is very difficult to measure, especially in road conditions. The article deals with issues related to the influence of the thermal state of...
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Metody usuwania zakłóceń podczas pomiarów polowych widm Ramana
PublicationW pracy zostały scharakteryzowane źródła zakłóceń występujące podczas pomiarów widm Ramana w warunkach polowych oraz sposoby redukcji ich wpływu na jakość rejestrowanych widm. Zaprezentowano wpływ czasu integracji na jakość rejestrowanych widm w przypadkach, gdy szumy własne spektrometru mają składową typu 1/f, dominującą w zakresie małych częstotliwości. Przedstawiono także wyniki uzyskane podczas pomiarów z detekcją synchroniczną,...
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Employing economical methods for pavement defects estimation
PublicationIt is a common practise that measurements of road surface conditions are made using professional and expensive apparatus. Typically a van or a truck equipped with a set of professional sensors i.e. laser scanners of surface is used, therefore the measurement update period is often quite long. Two alternative low-cost methods for estimating road pavement defects and failures were proposed and investigated by the authors. The first...
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Load function walking pedestrian on the footbridge.
PublicationModern foot bridges are more and more sensitive to variable load created by moving pedestrians. These are several reasons for that. Quickly growing up road infrastructure forces us to build foot bridges just to reconnect one piece of land, separated now by the new road or railway. These bridges are lightweight because the only live load acting on them comes from pedestrians.The paper focuses on the definition of human induces dynamic...
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MODELOWANIE WYBRANYCH MIAR BEZPIECZEŃSTWA RUCHU NA DŁUGICH ODCINKACH DRÓG
PublicationKażdego roku w wypadkach drogowych na świecie życie traci prawie 1,3 mln osób, co oznacza prawie niemal 3 tys. ofiar dziennie,. Tyle samo zabitych w ruchu drogowym odnotowujemy rocznie w Polsce. Ekonomiczne straty w wyniku tych wypadków wynoszą ok. 2% światowego PKB. W roku 2010 Organizacja Narodów Zjednoczonych (ONZ) przyjęła rezolucję pt. „Dekada działań na rzecz bezpieczeństwa ruchu drogowego na lata 2011 – 2020” rozpoczynającą...
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Comparison of Tire Rolling Resistance Measuring Methods for Different Surfaces
PublicationThe rolling resistance of car tires is one of the most important parameters characterizing tires today. This resistance has a very significant contribution to the energy consumption of wheeled vehicles. The climate crisis has forced tire and car manufacturers to place great emphasis on the environmental impact of their products. Paradoxically, the development of electric vehicles has led to an even greater importance of rolling...
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Pedestrian Safety at Midblock Crossings on Dual Carriageway Roads in Polish Cities
PublicationRoad crossings across two or more lanes in one direction are particularly dangerous due to limited sight distance and high vehicle speeds. To improve their safety, road authorities should provide safety treatments. These may include additional measures to reduce speed and narrow the road cross-section and the introduction of active pedestrian crossings. Equipped with flashing lights activated automatically when a pedestrian is...
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Analytical fluctuation enhanced sensing by resistive gas sensors
PublicationResistance fluctuations across polarised resistive gas sensors were studied in detail to evaluate sensor working conditions for detecting methane and ammonia at various concentrations. The 1/f noise component typically dominates other noise sources up to a few kHz and can be utilised to improve gas selectivity when compared with measurements of the sensor DC resistance. The Arrhenius plot was created and the activation energy for...
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Low frequency noise measurements in advanced silocon devices.**2003, 136 s.116 rys. bibliogr. 29 poz. maszyn. Pomiary małoczęstotliwościowych szumów zaawansowanych elementów krzemowych. Rozprawa doktorska /15.04.2003./ Inst. Natl. P. Grenoble Promotorzy: prof. dr hab. inż. L. Spiralski, dr CNRS G. Ghibaudo.
PublicationW pracy przedstawiono automatyczny system do pomiarów małoczęstotliwoscio-wych szumów struktur elementów półprzewodnikowych. System umożliwia automa-tyczne wyznaczanie charakterystyk stałoprądowych badanego elementu, pomiarszumów i wyznaczanie gęstości widmowej mocy w zadanym zakresie polaryzacji.Przytoczono wyniki przeprowadzonych testów systemu. Ważną składową pracy wy-niki pomiarów szumów tranzystorów MOS i bipolarnych...
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Impact of adverse winter weather on traffic flow
PublicationThe paper aims to analyse the impact of adverse weather in winter on traffic flow using data from a dual carriageway section of an express road located in Gdansk. For the purposes of the analysis, traffic and meteorological data were collected for a period of 15 months in 2014-2015 and aggregated to 5 minutes intervals. The impact of winter weather conditions on traffic flow was assessed by comparing aggregated traffic stream parameters...
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Assessing Roadside Hybrid Energy Absorbers Using the Example of SafeEnd
PublicationA combination of crash cushion and end-terminal, hybrid energy absorbing devices have been in use worldwide for a few years already. They include SafeEnd, a system Poland has recently introduced. Some road authorities have raised concerns as regards the operating conditions of the devices and how they work together with safety barriers. The objective of this research is to clarify the concerns and answer the following questions:...
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Wavelet-based denoising method for real phonocardiography signal recorded by mobile devices in noisy environment
PublicationThe main obstacle in development of intelligent autodiagnosis medical systems based on the analysis of phonocardiography (PCG) signals is noise. The noise can be caused by digestive and respiration sounds, movements or even signals from the surrounding environment and it is characterized by wide frequency and intensity spectrum. This spectrum overlaps the heart tones spectrum, which makes the problem of PCG signal filtrating complex....
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Advanced operating methods
PublicationSelected operating methods of resistive gas sensors were presented. The methods utilize flicker noise (1/f noise), which gives additional information about ambient gas when compared with the recorded changes of DC resistance only. Methods of flicker noise measurements were outlined. Recently developed prototype gas sensors comprising golden nanoparticle functionalized with organic ligands can generate intense flicker noise induced...
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Efficiency of gas detection algorithms using fluctuation enhanced sensing
PublicationEfficiency of various gas detection algorithms by applying fluctuation enhanced sensing method was discussed. We have analyzed resistance noise observed in resistive WO3- nanowires gas sensing layers. Power spectral densities of the recorded noise were used as the input data vectors for two algorithms: the principal component analysis (PCA) and the support vector machine (SVM). The data were used to determine gas concentration...
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Comparison of Acoustic and Visual Voice Activity Detection for Noisy Speech Recognition
PublicationThe problem of accurate differentiating between the speaker utterance and the noise parts in a speech signal is considered. The influence of utilizing a voice activity detection in speech signals on the accuracy of the automatic speech recognition (ASR) system is presented. The examined methods of voice activity detection are based on acoustic and visual modalities. The problem of detecting the voice activity in clean and noisy...
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Experimental and numerical analysis of the modified TB32 crash tests of the cable barrier system
PublicationRoad restraint systems, including safety barriers, are one of the means used to improve road safety. Currently, they can be allowed to general use after passing the specific crash tests. However, it is always important and desirable to evaluate their performance under various realistic conditions, which can happen on the roads. In this study, the behaviour of the cable barrier system in impact conditions different than assumed...
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The application of the Superpave method of climatic zones analysis in Poland with regard to bitumen performance grading
PublicationCurrently in Poland, similarly as in the other EU countries, road bitumens are tested and classified with regard to mainly the penetration value determined at the tempera-ture of 25C. It should be noted that this classification is not correlated with the cli-matic conditions in which the bitumens are to serve in the road pavement. Towards the end of the last century a new system of bitumen grading was developed and im-plemented...
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Risk assessment methodologies for pedestrian crossings without traffic lights – Warsaw case study – pedestrian safety assessment
PublicationBased on data from 2015 [1], it was found that 31% of all fatalities in road accidents in Poland were pedestrians. In places accessible to pedestrian traffic 74.2% of total accidents involving pedestrians were recorded. Approximately 53.9% of accidents involving pedestrians take place in the proximity of pedestrian crossings. In the context of improving the safety of vulnerable road users, an assessment of the condition of infrastructure...
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On the influence of the acceleration recording time on the calculation of impact severity indexes
PublicationThe paper concerns with the analysis of normative requirements pertaining to experimental setup of a crash test and its numerical modelling. An overview of parameters describing the collision of a vehicle with a road restraining system is presented. A short description of a concrete road safety barrier is presented. A brief description of numerical modelling procedures for crash tests is given as well. The parametric influence...
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Zagrożenia uczestników ruchu drogowego na drogach regionalnych
PublicationReferat zawiera analizę bezpieczeństwa ruchu drogowego na sieci dróg wojewódzkich. Przedstawiono poziom bezpieczeństwa na tle całej sieci drogowej oraz charakterystykę poszczególnych województw. Przedstawiono ranking województw ze względu na liczby wypadków i ich ofiar oraz wybrane wskaźniki. Zaprezentowano, jakie są najczęściej występujące rodzaje wypadków na drogach wojewódzkich oraz przedstawiono lokalizację wypadków pod kątem...
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Innowacyjne narzędzia zarządzania bezpieczeństwem transportu drogowego na poziomie regionalnym
PublicationW referacie przedstawiono założenia i cele Obserwatorium Bezpieczeństwa Ruchu Drogowego funkcjonującego w regionie Warmii i Mazur. Obserwatorium jest pierwszą taką jednostką w Polsce – zarówno na poziomie regionalnym, jak centralnym. Zostało powołane zgodnie z metodyką zaproponowaną w europejskim projekcie SafetyNet i wspólnie z Krajowym Obserwatorium Bezpieczeństwa Ruchu Drogowego, realizowanym przez Instytut Transportu Samochodowego, wejdzie...
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Decreasing CO2 Emissions By Reducing Tire Rolling Resistance
PublicationThe first motor vehicle was built by Nicolas Cugnot almost 250 years ago and since then there has been a continuous process of motor vehicles’ improvements, as well as development of new road pavements. The fuel crisis of the 70s of the 20th century made it clear to vehicle builders that measures should be taken to reduce vehicle fuel consumption and it contributed to an increased interest in electric vehicles. Although significant...
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Preliminary safety assessment of Polish interchanges
PublicationInterchanges are a key and the most complex element of a road infrastructure. The safety and functionality of interchanges determine the traffic conditions and safety of the entire road network. This applies particularly to motorways and express-ways, for which they are the only way to access and exchange traffic. A big problem in Poland is the lack of comprehensive tools for designers at individual stages of the design process....
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Application of PL-Grid Platform for Modeling of the Selected Acoustic Phenomena
PublicationDomain grids are specific computational environments, developed within the PLGrid Plus project. For the Acoustic domain grid two supercomputer grid based services were prepared. Dedicated software consists of the outdoor sound propagation module and psychoacoustical noise dosimeter. The results are presented in a form of maps of sound level and Temporary Threshold Shift (TTS) values, therefore the services may play an informative...
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Nonadditivity of quantum and classical capacities for entanglement breaking multiple-access channels and the butterfly network
PublicationWe analyze quantum network primitives which are entanglement breaking. We show superadditivity of quantum and classical capacity regions for quantum multiple-access channels and the quantum butterfly network. Since the effects are especially visible at high noise they suggest that quantum information effects may be particularly helpful in the case of the networks with occasional high noise rates. The present effects provide a qualitative...
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Identification of hydroacoustic wave sources of ship in motion
PublicationThis paper deals with results of identification tests of acoustic field spectrum of underwater noise generated by ship in motion. The field is connected with acoustic activity of ship mechanisms and devices in operation. Vibration energy generated by the mechanisms and devices is transferred through ship structural elements to surrounding water where it propagates in the form of acoustic waves of a broad band of frequencies. In...
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The influence of position of the post or its absence on the performance of the cable barrier system
PublicationRoad safety barriers are used to increase safety in potentially dangerous places on the roads. They are designed and installed on the roads to prevent any vehicle from getting outside the travelled way or from entering the opposite lane of the road. Barriers, which are used on European roads, have to undergo full scale crash tests according to the EN 1317 standards. Nowadays as a supplement to real crash tests, numerical simulations...
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Application of Support Vector Machine for Determination of Impact of Traffic-Induced Vibrations on Buildings
PublicationThe aim of the article is to present an algorithm of Support Vector Machine created to forecast the impact of traffic-induced vibrations on residential buildings. The method is designed to classify the object into one of two classes. The classification into the first class means that there is no impact of vibrations on the building, while classification to the second class indicates the possible influence and suggests the execution...
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Proposed method for estimating the costs of safety barrier life cycle
PublicationToday barrier types are frequently selected for their price with little regard for the total costs the structure will incur over its lifetime. One of the basic tools designed to manage road infrastructure is the life cycle cost method (LCC, Life cycle cost). It sums up the costs to plan, design, build, operate (use and maintain) and decommission a road structure. Having developed dynamically at the turn of the century the method...
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Stężenie formaldehydu w wodach spływnych z arterii komunikacyjnych, powierzchni dachów budynków i koron drzew, wodach gruntowych i rzecznych oraz w opadach i osadach atmosferycznych na terenie aglomeracji miejskich = Formaldehyde in road runoff, roof runoff, ground water, river, atmospheric precipitation and deposition from highly urbanized regions
PublicationOznaczono stężenie formaldehydu w próbkach wód opadowych, spływnych z arterii komunikacyjnych, powierzchni dachów budynków i koron drzew, wód gruntowych i cieków wodnych oraz w próbkach śniegu, szronu i sadzi. Próbki pobierano przez okres 7 miesięcy w trakcie wystąpienia opadu lub osadu atmosferycznego lub tuż po jego ustąpieniu. Pomiar zawartości formaldehydu wykonywano stosując metodę szybkich testów spektrofotometrycznych w...
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Dynamical description of quantum computing: generic nonlocality of quantumnoise
PublicationWe develop a dynamical non-Markovian description of quantum computing in the weak-coupling limit, in the lowest-order approximation. We show that the long-range memory of the quantum reservoir (such as the 1/t4 one exhibited by electromagnetic vacuum) produces a strong interrelation between the structure of noise and the quantum algorithm, implying nonlocal attacks of noise. This shows that the implicit assumption of quantum error...
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Influence of a Lighting Column in the Working Width of a W-Beam Barrier on TB51 Crash Test
PublicationRoad equipment, such as, e.g., road safety barriers and lighting columns, are subject to certification according to the EN1317 standard to be allowed for use on European roads. In engineering practice, due to the terrain conditions, there are cases where other road equipment is installed within the working width of road safety barriers. Such situations are not considered during the certification process. Hence, the aim of this...
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Automatic labeling of traffic sound recordings using autoencoder-derived features
PublicationAn approach to detection of events occurring in road traffic using autoencoders is presented. Extensions of existing algorithms of acoustic road events detection employing Mel Frequency Cepstral Coefficients combined with classifiers based on k nearest neighbors, Support Vector Machines, and random forests are used. In our research, the acoustic signal gathered from the microphone placed near the road is split into frames and converted...
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Evaluation of Street Lighting Efficiency Using a Mobile Measurement System
PublicationThe issue concerns the initial stage of work on a method for performing a rapid assessment of the energy efficiency and illuminance of a street lighting installation. The proposed method is based on simultaneous measurement of illuminance from three lux meters placed on the roof of the vehicle. The data are acquired in road traffic, while the vehicle is driving. The proposed solution will allow in the future to quickly and reproducibly...
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A Proposed Machine Learning Model for Forecasting Impact of Traffic-Induced Vibrations on Buildings
PublicationTraffic-induced vibrations may cause various damages to buildings located near the road, including cracking of plaster, cracks in load-bearing elements or even collapse of the whole structure. Measurements of vibrations of real buildings are costly and laborious. Therefore the aim of the research is to propose the original numerical algorithm which allows us to predict, with high probability, the nega-tive dynamic impact of traffic-induced...
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Suppression of distortions in signals received from Doppler sensor for vehicle speed measurement
PublicationDoppler sensors are commonly used for movement detection and speed measurement. However, electromagnetic interference and imperfections in sensor construction result in degradation of the signal to noise ratio. As a result, detection of signals reflected from moving objects becomes problematic. The paper proposes an algorithm for reduction of distortions and noise in the signal received from a simple, dual-channel type of a Doppler...
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Wpływ barier ochronnych na poziom bezpieczeństwa ruchu drogowego
PublicationWypadki drogowe wciąż stanowią znaczną przyczynę zgonów, dlatego bardzo ważnym jest odpowiednie kształtowanie otoczenia drogi – by mogło ono uzyskać miano „wybaczającego”. Artykuł stanowi wprowadzenie do tematyki drogowych barier ochronnych, i jest częścią pracy dyplomowej realizowanej na Politechnice Gdańskiej, w ramach której autorzy analizują zależności pomiędzy wypadkami a omawianymi urządzeniami BRD. W artykule przedstawiono...
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Badanie stanu nawierzchni drogowej z wykorzystaniem uczenia maszynowego
PublicationW artykule opisano budowę systemu informowania o stanie nawierzchni drogowej z wykorzystaniem metod cyfrowego przetwarzania obrazów oraz uczenia maszynowego. Efektem wykonanych prac badawczych jest eksperymentalna platforma, pozwalająca na rejestrację uszkodzeń na drogach, system do analizy, przetwarzania i klasyfikacji danych oraz webowa aplikacja użytkownika do przeglądu stanu nawierzchni w wybranej lokalizacji.
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Analysis of radiometric signal in sedimentating suspension flow in open channel
PublicationThe article discusses issues related to the estimation of the sedimentating solid particles average flow velocity in an open channel using radiometric methods. Due to the composition of the compound, which formed water and diatomite, received data have a very weak signal to noise ratio. In the process analysis the known determining of the solid phase transportation time delay the classical cross-correlation function is the most...
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The Application of Fibres from Recycled Postconsumer Tyres for Concrete Reinforcement
PublicationPoland as a Member State is obliged to implement the EU specific environmental legislation focused on the reduction, transport and treatment of waste. The Landfill Directive prohibited the landfilling of whole tyres and their by-products. Although the EU Directive of Waste limits the use of tyres as secondary fuel, Poland is still the EU leader in burning tyres in cement kilns. Post-consumer tyres are utilised in a number of...
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Characterization of aggregate interlocking in hot mix asphalt by mechanistic performance tests
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Significance of cement-stabilised soil grain size distribution in determining the relationship between strength and resilient modulus
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Determination of Equivalent Axle Load Factors on the Basis of Fatigue Criteria for Flexible and Semi-Rigid Pavements
PublicationArtykuł przedstawia analizę współczynników równoważności obciążenia osi na podstawie kryteriów zmęczeniowych stosowanych w mechanistyczno-empirycznych metodach projektowania nawierzchni. Określono wzory służące do obliczania współczynnika w oparciu o szereg kryteriów zmęczeniowych. Podano wartości liczbowe współczynników.
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Influence of aggregates angularity on the locking point of asphalt mixtures
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Consideration of dynamic loads in the determination of axle load spectra for pavement design
PublicationAxle load spectra constitute a crucial part of the data for pavement design and pavement distress analysis. Typically, axle load spectra represent static load from vehicles and do not include dynamic loads generated by vehicles in motion. While dynamic loads can significantly contribute to faster pavement distress, this fact is mostly omitted in pavement design methods. The paper presents a methodology for consideration of dynamic...
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Behaviour of asphalt concrete in cyclic and static compression creep test with and without lateral confinement
PublicationArtykuł przedstawia wpływ metodyki badań na określanie parametrów betonu asfaltowego. Wykazano, że badania pełzania bez skrępowania bocznego w większym stopniu uwypuklają wpływ asfaltu na parametry badanego betonu asfaltowego natomiast w badaniach ze skrępowaniem bocznym, zarówno rola asfaltu jak i szkieletu mineralnego jest uwzględniana przy ocenie parametrów betonu asfaltowego. Ponadto wykazano, że lepszymi miarami do oceny betonu...
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Verification of the criteria for evaluation of water and frost resistance of asphalt concrete
PublicationThe paper presents the results of field investigation - condition survey of existing pavements and the results of laboratory tests on water and frost resistance of samples cored from the these pavements. The purpose of testing was to verify the criteria for evaluation of the resistance of asphalt concrete to the action of water and frost by way of comparing the results of field and laboratory tests, followed by evaluation of their...