Martina Zagvozda

Possibilities of bioash application in road building

Biopepeli su neizbježan proizvod ispunjavanja zahtjeva za sve vecom primjenom obnovljivih izvora u proizvodnji energije. Ekoloski i ekonomski prob

Freeze-thaw resistance assessment of cement-bound steel slag aggregate for pavement structures

Abstract This paper investigates the durability of cement-bound layers with steel slag as a partial aggregate replacement. Mixtures with various amounts of slag and cement are investigated for their durability after freeze–thaw cycles and exposure to de-icing agent. Optical microscopy analysis is conducted as a method for assessing the behaviour of low-strength material in order to determine why the application of slag resulted in greater compressive strength and durability properties. It was shown that this method is suitable for providing more details and insights into the material’s internal structure. All the mixtures show a loss in compressive strength after exposure to freeze–thaw cycles and de-icers, but this loss is more pronounced in mixtures with gravel-only aggregates. A strong linear correlation is obtained between 28-day compressive strength and retained compressive strength after 10 freeze–thaw cycles. The main conclusion of the research presented here is that steel slag aggregate presents good potential for use in adverse climates, and it is possible to predict the freeze–thaw resistance of cement-bound aggregate on the basis of compressive strength.

The potential of bioash for utilization in road construction in eastern Croatia

Abstract In recent years usage of biomass as energy source has intensified in eastern Croatia. Newly built biomass power plants generate great amounts of bioash that is being disposed at landfills. Due to its favorable properties bioashes could be reused as alternative materials in road construction or road fundation. Therefore, research on application of bioashes in construction industry is being conducted at Faculty of Civil Engineering in Osijek. The main motivation behind this research, in a form of biomass and bioash production in eastern Croatia as well as international research on potential application of this types of bioashes, is show in this paper.

DEVELOPMENT OF TRAM TRAFFIC IN THE CITY OF OSIJEK

The need for the introduction of trams in Osijek in the late 19th century was largely due to the poor connectivity between the areas of the city and t

EXAMPLES OF TRAFFIC NOISE ABATEMENT IN THE CITY OF OSIJEK

Noise pollution is a major environmental problem in urban spaces worldwide. The first step toward noise abatement is determining and evaluating noise levels in order to best prioritize and implement protective measures. The city of Osijek, as is obligated by law and the European Directive, has done this by creating a noise map. In this paper, we present measures for noise abatement, showing some of the measures implemented in Osijek based on their noise map, and review possible methods for abating noise in the most vulnerable areas.

Usage of Alternative, Environmentally Acceptable Materials—Experience from Eastern Croatia

The concept of sustainability should be the main guiding principle in the construction industry today. It mandates conservation of natural resources and thus lower impact on the environment. In road construction, part of construction industry that consumes largest quantities of natural materials, sustainable building and maintenance of roads is possible trough application of secondary materials. Usage of industrial and construction waste presents energy, ecologically and financially effective alternative. Republic of Croatia, even as a new member of the European Union, still lags behind the well-established practices of the application of alternative materials in different European countries. The reasons for this can be found in the current legal and technical regulations for alternative materials. In this paper, the existing regulations for alternative materials and the impact they have on the application of these materials in practice in the region of eastern Croatia will be shown.

COMPARISON OF CROATIAN AND EUROPEAN STANDARDS FOR DETERMINING THE FROST SUSCEPTIBILITY OF HYDRAULICALLY BOUND MIXTURES

The base layer of a multi-layered pavement structure is often a cement-bound material, which combines an aggregate with cement binder. This load-bearing layer is quite rigid, which improves pavement properties, including frost resistance, and extends the life cycle of the pavement. In geographic areas with low temperatures and significant ground water, the bearing capacity of pavement structures can be reduced by volume deformations from freezing and thawing. Cold winters and frost-susceptible soil are present in eastern Croatia and in the city of Osijek. Thus, in this paper we examine the frost susceptibility of cement-bound aggregates, made with materials commonly used in Croatia, in accordance with the current Croatian standard HRN U.B1.050 and a new European standard EN 13286-54. The test mixtures did not meet the conditions for frost-resistant materials. To meet these conditions, one must use a higher cement ratio or a cement with a higher strength class.