Authors:Esat Gashi, Ljupčo Dimitrievski, and Darko Ilievski
Asphalt paved roads prematurely exhibit a cracking pattern similar to that in the old underlying pavement. The cracking in the new overlay surface is due to the inability of the overlay to withstand shear and tensile stresses created by movements concentrated around preexisting cracks in the underlying pavement. This movement may be due to traffic loading causing differential deflections at cracks in the underlying pavement layers, expansion or contraction of subgrade soils, expansion or contraction of the pavement itself due to changes in temperature, or combinations of these phenomena. Due to heavy deformation of asphalt paved surface, using European funds, the Government of Macedonia initiated rehabilitation of Corridor X close to the Tetovo section. For the reconstruction of this important section of the motorway, an experimental programme was conducted to determine the effects of geogrid reinforcement on mitigating reflection cracking in asphalt overlays. The objective of this study is to assess the inclusion of geogrid in the pavement cross-section and the accumulation of permanent deformation. The geogrid position, type of existing pavement, temperature, and joint/crack opening were analyzed in three site trial tests. Crack propagation under repeated loading was monitored as well. The results indicate a significant reduction in the rate of crack propagation in reinforced samples compared to unreinforced samples of old asphalt pavement. The presented pavement design procedure could be tailored to the specific needs of the project and implemented in various road rehabilitation projects.
(vertical radius, roadsurface, design speed, weather conditions, vehicle mechanism, and the time of day). After that, comparing the results from the human drivers with results from other sensors were mentioned previously. The resulted sight distances will
Authors:Michelle Mothé, Leni Leite, and Cheila Mothé
The quality of a road relies on the good use of the on road surface and its maintenance along the years. The technology used
and the corrections contributes to the prevention of early road destructions. Pavement with polmyer and others additives exhibits
greater resistance to rutting, thermal cracking, and decreased fatigue damage, stripping and temperature susceptibility. Samples
of CAP 40, SBS 440/02, L 1861/04, L 784/05 and L 2000/04 were analyzed by thermogravimetry (TG), derivative thermogravimetry
(DTG), differential thermal analysis (DTA) and FTIR. Thermal characterizations showed that the main decomposition stage refers
to asphaltenes and samples with additives exhibited a slight increase in thermal stability. The kinetic study, by Kissinger,
showed that the sample with the highest stability was the SBS 440/02. Fourier transform infrared spectroscopy (FTIR) analysis
suggested that these asphalt samples were originated from light oil.
Authors:S. Olabanji, A. Haque, S. Fazinic, R. Cherubini, and G. Moschini
As a rapidly growing vast country, there is need in Nigeria to develop alternative energy sources to meet its ever increasing energy demands. Tar sands apart from its popular use as a source of asphaltic material for road surfacing is a new energy raw material in Nigeria. The immense industrial applications and utilization of the by-products of tar sands provide great incentives for its development. PIGE and PIXE techniques were employed for the determination of the major, minor and trace elemental concentrations in Nigerian tar sands including sulfur which occurs as pyrites, organic sulfur and sulfates. Proton beams produced by the 7 MV CN and 2.5 MV AN 200 Van de Graaff accelerators at I.N.F.N. Laboratori Nazionali di Legnaro (LNL) at Padova, Italy, were used for the PIGE and PIXE analysis, respectively. Results of this novel study are presented, discussed, and compared with some data from previous worker and values from Athabasca (Canada).
The objective of the research of tires was to determine the dynamic rolling radius and to apply it to wheel slip calculations with special respect to vertical wheel load and to tire inflation pressure. It is typical of mechanical four-wheel drive tractors that there is a definite additional power in the tractor power chain. This additional power is dependent on the difference between the front wheel and rear wheel peripheral speeds. Further-more, the purpose was to determine the effect of additional slip on four-wheel drive tractors operated without drawbar pull. Experiments were performed on asphalt surfaces and fields. A new measurement method was developed, and a device was constructed for the implementation of three tractor wheel drive operational modes (four-wheel drive, rear-wheel drive and front-wheel drive). As the result of the experiments, a relationship was found to describe the dynamic rolling radius for low-profile radial tires tested on rigid road surfaces. On this basis, the classical slip calculation method was modified. This phenomenon appears only on hard roads and soil surfaces with high adhesion coefficients and only within the low drawbar pull range.
Authors:Flóra Hajdu, Péter Szalai, Péter Mika, and Rajmund Kuti
, Birk W. , Nordenvaad M. L.
Extended Kalman filter for vehicle tracking using roadsurface vibration measurements , IEEE 51st IEEE Conference on Decision and Control , Maui, HI, USA , 10
. Fig. 3. Total trajectory view of the bicycle on the map The training process was also photographed to show road conditions and profile completing the distance of 26.52 km for each 1.5 km (see Fig. 4 ). As can be seen from photographs, the roadsurface
, Vol. 6 , No. 1 , 2011 , pp. 141 ‒ 154 . 10.1556/Pollack.6.2011.1.13  Litak G. , Borowiec M. , Friswell M. I. , Szabelski K. Chaotic vibration of a quarter-car model excited by the roadsurface profile , Communications in Nonlinear
Authors:M. Prochon, G. Janowska, A. Przepiorkowska, and A. Kucharska-Jastrzabek
found an improvement in breaking on an ice-covered roadsurface.
Loreth [ 16 ] has published a patent specification concerning the use of coconut-keratin fiber mixtures a component of winter tire treads. The mixture consisted of cellulose fibers