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[Numberless Heading] Abstract[Normal] Manuscript preparation for CETRA 2014 proceedings is a fairly simplified process. Everything you need for a properly formatted article is contained in this template document which uses a feature of Microsoft Word called Styles. A style is a set of formatting characteristics that you can apply to text in your document to quickly change its appearance. When you apply a style, you apply a whole group of formats in one simple step. For example, you may want to format the sections headers to make them stand out. Instead of changing the headings one by one, you can give them a style and change them all at once. All the styles in this document are preformatted so you only need to pick an appropriate one for the part you are working on. In this example document each section that uses a specific style starts with a style name surrounded by square brackets for easy identification. The text you are reading at the moment is formatted using [Normal] style, whilst the heading above it uses [Numberless Heading] style and so on. These words serve only as a reference and should be omitted in the paper you submit. Figure 2. This group may be expanded to a list by clicking on the icon in its lower-right corner which will open a window similar to the one in Figure 3.

HDPE geomembranes are usually used in bottom liners in landfills. Their integrity is required during installation and during the lifetime of the landfill. It is commonly accepted by researchers and suggested by different technical specifications that there should be no strain present during the installation of a geomembrane, although some of them propose that the strain during the installation should be no more than 3%. This is not easy to satisfy in some situations. Strains in the geomembranes can be induced by overnight temperature changes, before covering of the geomembrane (cold weather causes stretching of the geomembrane), which in turn may create trampoline effect in the veneer of sloped foundation soil. Covering of the geomembrane can wait higher temperatures to bring geomembrane into good close contact with the substructure profile or can be forced in order to bring the geomembrane into that position, which means accumulation of strains in the geomembranes. The question arises: What are the changes that occur in geomembrane properties for thermally and/or mechanically induced strains in the geomembranes, are they different, and how the level of induced strain and aging of strained geomembrane can change its properties? This paper presents a large project related to laboratory study of this phenomenon, and the first results regarding its short-time behaviour. Mechanical and structural changes of the geomembrane properties are tested and monitored in the first few days after inducing thermal and/or mechanical strains of 0%, 3% and 6%. Specially developed frames were used for the preparation and conditioning of the geomembrane samples. Test results suggest that strains induced by temperature drop and/or mechanical extension do not affect short-term geomembrane properties. Research continues on samples that will be monitored for four years.

During road construction, granular materials for the unbound base course (UBC) and cement-bound base course (CBC) are mostly compacted by vibratory rollers. A widespread laboratory test for determining the optimal moisture content (OMC) and maximum dry density (MDD) of the mixture for installation in UBC and CBC is the Proctor test. Considering that the Proctor test does not produce any vibrations during compaction, this paper compares the Proctor test and the vibrating hammer test. The examination was conducted on UBC and CBC with varying cement content and aggregate types. All mixtures were compacted by both methods with the aim of determining the compaction and strength characteristics. The results indicated the high comparability of the two test methods for mixtures with natural aggregate in terms of MDD, OMC, density and strength characteristics (California bearing ratio (CBR) for UBC and 28-day compressive strength for CBC). For mixtures with higher cement content, the OMC difference depending on the laboratory compaction method used can be significant, so the laboratory compaction method should be chosen carefully, particularly for moisture-susceptible materials. This paper also reveals that by increasing the proportion of rubber in the mixture, the compaction and strength characteristics differ significantly due to the compaction method. Therefore, when using alternative and insufficiently researched materials, the compaction method should also be chosen carefully.

In the past twenty years in Croatia, a number of reinforced earth constructions have been built, of which two reinforced earth walls stand out due to their dimensions: Strikići and Sveta Trojica. In the building of these walls, polyester strips were used as reinforcement elements, whereas as fi ll material crushed stone aggregate was used. For designing these constructions, knowledge about the interaction mechanisms between the polyester strip and the soil is required. So far, most of the published studies have been directed to the determination of the friction interaction coeffi cient of the polyester strip and the fi ll material which was sand or gravel, whereas tests on the interaction between the geosynthetic strip and the crushed stone aggregate have not been performed. In order to determine the friction interaction coeffi cient between the crushed stone aggregate which is commonly used as fi ll material and the geosynthetic strip, pull-out tests of the polyester strip were carried out. Apart from pull-out tests, large direct shear tests were performed to determine shear strength parameters of crushed stone strength. Predictions from the numerical model were compared to a series of pull-out tests, proving that the numerical model provides reasonable predictions of pull-out behavior.