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Preliminary Studies to Use Textile Fibers Obtained from Recycled Tires to Reinforce Asphalt Mixtures

Abstract

The use of crumb rubber in the modification of asphalt has occurred because of the problems related to disposal of scrap tires. However, the use of scrap tires in asphalt pavements, known as asphalt rubber pavements, can minimize environmental impacts and maximize conservation of natural resources. The textile fibers from recycled tires are typically disposed of in landfills or used in energetic valorization, but similar to other fibers, they can be used as a valuable resource in the reinforcement of engineering materials such as asphalt mixtures. Thus, this work aims at studying the use of textile fibers recycled from ground tires in the reinforcement of conventional asphalt mixtures. The application of textile fibers from ground tires was evaluated through laboratory tests on specimens extracted from slabs produced in the laboratory. Indirect tensile tests were performed on a series of nine asphalt mixtures with different fiber and asphalt contents and compared with a conventional mixture. The results obtained from a 50/70 pen asphalt were used to define three asphalt mixture configurations to be used with 35/50 pen asphalt. The results indicate that the textile fibers recycled from used tires can be a valuable resource in the reinforcement of asphalt mixtures.

Open access
Problems of Polish enterprises in the field of innovation

Abstract

Innovative activity of enterprises in Poland is mostly generated by European funds that concern boosting European regions based on its significant resources and new technologies. Polish enterprises development within innovations is based mainly on accumulating new products and new technologies that improve organization and increase sale of products and services. Papers presents research findings that concern problems resulting from the innovations implementing in Polish enterprises comparing with European results. There is presented European Innovation Index providing a comparative assessment of the innovation performance at the country level of the EU Member States and the Regional Innovation Scoreboard (RIS) that presents results of innovative activity in Polish and European enterprises including regional data from the Community Innovation Survey (CIS).

Open access
Prospects for Production and Consumption of Second Generation Biofuels in Ukraine

Abstract

The article analyzes the current state of production of second generation biofuels in the world and evaluates the possibility of launching such production in Ukraine. The work is topical due to the fact that liquid biofuels can replace a certain share of motor fuels consumed in Ukraine, thus contributing to the strengthening of the country’s energy independence. The purpose of the study is to assess feasibility of a project on the production of second generation bioethanol in Ukraine; the task is to carry out a preliminary feasibility study for such a project. The analysis of the study of pure co-substrate fermentation and as a supplement for cattle manure proves that the maximum biogas yield obtained using alcohol stillage in a ratio of 40-80% increased compared to fermentation of pure cattle manure. The use of pure bards compared to the bard and the slurry mixture increases the maximum yield of biogas. It was found that the biogas obtained from the use of alcohol stillage is a high con-sumption of biogas with the methane content of between 70 and 78%.

Open access
Review of Policies for Promotion of Electric Vehicles

Abstract

This paper presents the review of policies and their possible effects for promoting the use of electric vehicles. Suggestions on faster implementation of electric vehicles can also be identified within best practices from abroad. Various countries have adopted different policies to promote the use of electric vehicles which include fiscal or other forms of incentives that would persuade people into buying electric vehicles. Possible effects are hard to determine since many variables affect a consumer’s purchasing decisions. That is why identification of policies that have proven to be successful and those that have not achieved projected results and should be improved is necessary. Research has shown that countries with most promising policies for promotion have the biggest share of electric vehicles and invest the most in their promotion (fiscal incentives).

Open access
Selected Properties of Multilayer Films Applied for Vacuum and Modified Atmosphere Packaging Systems

Abstract

The aim of the research was to determine the selected properties of packaging materials applicable for vacuum and modified atmosphere packaging. Six samples of multilayer films with different composition were tested to evaluate the thickness, basic weight, density and the mechanical properties in elongation and puncture tests. Zwick/Roell apparatus equipped with elongation jaws and a puncture pin was used in the experiments. The tensile modulus, tensile strength, elongation at tensile strength, stress at break and work at break were investigated with the elongation test, whereas the breaking force, puncture work and extension at break were evaluated with the puncture test. The obtained results allow conclusion that the thickness and basic weight of the packaging films used in the vacuum system was higher comparing with the MAP system. Analyzing the results of the elongation modulus and stress at break it was reported that the materials used for food packaging in the MAP system were characterized with better properties, whereas elongation at the tensile strength was higher for films applied in the vacuum system, except for a film with a metalized layer. The highest resistance for puncture was evaluated for OPET/PE film used in MAP packaging. The extension at break under the puncture test was higher for films dedicated for vacuum packaging suggesting their better resistance for the mechanical damage by a thin pin. Several correlations between physical and mechanical properties of multilayer films were found.

Open access
Simultaneous Influence of the Track Axis Curvature and the Support Line Obliquity at Railway Bridge Superstructures with Steel Beams Embedded in Concrete

Abstract

For new railway bridges with small spans (L ≤ 35.00 m) superstructures with steel beams embedded in concrete are recommended and used, which can ensure the requirements of strength and especially stiffness, regardless of velocity.

In all the design prescriptions used so far for superstructures with steel beams embedded in concrete, and even in the technical literature, there is little information and data on the influence of the support line obliquity and the track axis curvature in the design and calculation of these types of structures.

In the design code, if certain conditions related to the geometry of the superstructure are met (obliquity, curvature) the calculation is a simplified one, made on a single isolated longitudinal beam of the deck; otherwise, if the conditions are not met, finite element program analysis is recommended.

The article aims to study the situations in which the requirements of the design prescriptions are not met.

Open access
Supervision of measuring equipment based on risk management and ISO 9001

Abstract

The study presents the results of analysis of the possibilities of measuring equipment supervision, taking into account the requirements of the ISO 9001: 2015 standard and risk management present there. As it has been shown, it is possible to use (mentioned in point 6.1 of indicated standard) a risk management method for skilfully managing a measuring equipment. Orientation of business to risk is one of the elements of the ISO 9001 standard, which does not specify exactly how the method of its implementation should looks like. Generally, it orders to manage risk wherever goals appear. The targets also appear in the field of supervision of measuring equipment. Therefore, in the elaboration, apart from the requirements analysis, the concept of a five-stage methodology for implementing a risk-based approach to management of measurement equipment was presented. The matrix method was used to assess the risk. Within this method two elements were assessed: probability and potential effects of the risk occurrence. Application of the proposed concept may contribute to a more efficient and effective management of measuring instruments.

Open access
Technical aspects of the dentist’s work safety

Abstract

In the work of a dentist there are many factors that affect the occupational risk. They cover the area of the human factor, work organization and technical area. The latter often determines the safety and ergonomics of the workplace. The purpose of this article is to identify occupational hazards in the work of a dentist, with particular emphasis on the technical area. The method used in the article is a survey supported by observation with elements of a direct interview. The research tool used in the article is a questionnaire in the form of a checklist.

Open access
Testing the Functionality and Performance of a Rail Damper

Abstract

The rail dampers are mechanical devices which work as dynamic absorbers to reduce the rail vibration and rolling noise. The paper shows the experimental results from the functionality and performance testing of an experimental demonstrative rail damper. The vibration attenuation takes the highest values, namely 6-22 dB, between 160 and 1000 Hz.

Open access
Thermo-physical characteristics of acrylic-based building external isolation panels produced from different geological materials

Abstract

Here we describe a new type of environmentally sensitive insulation panels which can be used on exteri-or wall surfaces to minimize all the negative aspects of existing coating materials by taking advantage of natural rock properties. We investigate the decorative characteristics and insulation performance of this new product, obtained by applying materials from different lithologies to Expanded Polystyrene Surfaces (EPS). First, a mortar with 25% acrylic and 75% sand was applied to the EPS by a stripping method using sand size materials from various lithologies (granite, micaschist, basalt, quartzite, and pumice). To determine the optimum thickness, insulation panels containing plaster of 2, 4, 6, and 8 mm thickness were prepared for each lithology. Their thermal conductivity coefficient, bending and compressive strength were tested. Predictably, thermal conductivity coefficient yielded lowest values in 2 mm panels and highest in 8 mm panels for all lithologies. The bending strength also increased proportionaly with thickness. In the compressive strength tests, the highest values were measured for the 2 mm panels while relatively low values were obtained for the 4, 6 and 8 mm panels, except for the micaschist and basalt-based panels. As a result, basalt and pumice offer superior features in the three measured parameters, so, it is expected that different combinations of these two lithologies would offer positive features. In this context, considering its high fire resistance and low thermal conductivity coefficient perpendicular to the planar surface of muscovites, micaschist is the third lithology that can be utilized with the two materials mentioned above. Compared with previous materials, the products investigated in this study are cost effective because they reduce paint costs, application time and total building load. The geomaterials also have aesthetic appeal.

Open access