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Abstract

Special requirements are placed on finishing materials and foundations for these materials. The technical datasheets for wooden floors contain detailed moisture guidelines regarding counter-floors for these materials. To check the moisture level, the carbide method (CM method) is recommended by manufacturers and many specialists. The authors of the paper performed moisture tests for various counter-floors (anhydrite and cement jointless floors, cement-sand mixtures) using the direct gravimetric (laboratory) method and the carbide method. Test results were collected and analyzed.

Abstract

The aim of the study was to characterize the components of crude oil, with particular emphasis on those that have a toxic effect on organisms, and to describe the sources of pollution and the methodology for determining these compounds in aqueous solutions. In addition, the study presents the legal provisions in the field of petroleum compounds and practical methods for their removal in the event of uncontrolled emission of these compounds into the aquatic environment as well as methods used in the treatment of wastewater loaded with these compounds.

Abstract

Sustainable development of the built environment in developing countries is a major challenge in the 21st century. The use of local materials in the construction of buildings is one of the potential ways to support sustainable development in both urban and rural areas where burnt clay bricks are used predominantly. This work focuses mainly on the use of polypropylene micro fibers in ordinary Cellular Lightweight Concrete blocks. The main objective is to develop a high-performance fibre reinforced cellular concrete to provide a better alternative than clay bricks for structural applications of masonry. This paper presents the stress-strain behaviour of polypropylene fibre reinforced Cellular Lightweight Concrete stack bonded prisms under axial compression. Masonry compressive strength is typically obtained by testing stack bonded prisms under compression normal to its bed joint. Use of micro-fibres enhances the pre-cracking behaviour of masonry by arresting cracks at micro-scale in the post-peak region. These efforts are necessary to ensure that CLC blocks become more accepted in the world of building materials and considered as a reliable option for providing low-cost housing.

Abstract

Today, much of the world’s waste, in particular used tires, is accumulating as a potential source of major environmental and economic problems. In order to better preserve the environment, and in the face of changes in the legislation in force, many recovery actions have been carried out especially in the field of building materials.

The present research aims to contribute to the study of the mechanical properties and durability of concretes based on rubber aggregates. To achieve this objective, we have contemplated incorporating therein amounts of rubber granules according to different volume substitution percentages being 10%, 17.5%, and 25%. A comparison of the results with a control concrete has been established.

The obtained results make it possible to demonstrate that the substitution of a percentage of sand by rubber granules decreases the mechanical strengths and increases the expansion in water. On the other hand, it improves the resistance to attack from H2SO4, Na2SO4, and seawater. The latter is evaluated by the loss and gain in mass as well as the loss in mechanical resistance, especially in the long term (more than 90 days), decreases drying shrinkage, thus decreasing microscopic cracks and providing better durability.

Abstract

To assess the technical condition of a structure and design it using existing elements, it is necessary to know its parameters. For existing facilities, it is often not possible to get a sample of material and examine it directly in the laboratory. For this reason, in situ nondestructive testing is very important.

The main goal of the paper is to present the issues related to determining the strength parameters of a particular wood based on the non-destructive sclerometric test performed with a wood sclerometric hammer. The study also presents the results of the impact of pinewood density on its compressive strength.

Abstract

Numerous studies have shown that the non-destructive testing has proved the exceptional role in supervising the quality of concrete. Today, they represent an alternative that contributes to the resolution of materials diagnostic problems without altering them. This work presents an experimental study using a pulse-echo method that has the advantage of generating two types of wave (compressional and shear) by a mode conversion using just one transducer. The samples were made in a prismatic form. The results recovered from backscattered echoes are extracted using an estimation algorithm. These data were exploited to determine velocities of the tested material then the reflection coefficients for related them with the compressive strength. The tests were conducted with six samples with varied water/cement ratio. The results obtained showed that the prism technique has the potential to evaluate characteristics cementitious material using this proposed process.

Abstract

The article looks at the latest trends in solving the problem of garbage collection, segregation and disposal in urban housing estates in the scope of design, architectural and spatial solutions. The paper adopts a method of analysing existing applications in view of globally shifting living conditions. As a result of the conducted analyses, a set of features and factors was singled out, ranging from functional-spatial, through transport and ergonomic to social and aesthetic ones. Also, conclusions that should be taken into account when determining the principles for designing these structures were presented.

Abstract

The present study focuses on the upper Neogene deposits, called the “Poznań Clays”, that cover more than 75,000 km2 of Poland. They are situated between the first mid- Polish lignite seam and the glaciogenic deposits of the Pleistocene age. Lithostratigraphically, the “Poznań Clays” belong to the uppermost portion of the lignite-bearing Grey Clays Member and the whole Wielkopolska Member (Poznań Formation). The examined fine-grained sediments include mud-rich floodplain deposits with palaeosol remnants and large sandy-muddy or muddy palaeochannel bodies. Therefore, taking into account facies analysis, cross-sectional geometry, and the planform of the palaeochannels, it can be stated that the “Poznań Clays” formed in the environment of a late Neogene anastomosing river.

Abstract

Designing retaining structures depends on many factors, primarily the function of the retaining structure and soil conditions. It is not easy to choose the right retaining structure due to the great variety of their structural and material solutions. Preliminary numerical analyses in this case can be very useful. This article presents the results of numerical analyses of the behaviour of retaining structures and soil for various structural and material solutions as well as defined soil and water conditions. Six variants of retaining structures were analysed, in which the type of retaining walls, the materials used and the height of the walls were varied. The assessment was done basing on maps of stress and displacement of the retaining structure and soil. An additional factor in the selection of retaining structures are costs, durability and lead time. The finite element method allows the analysis of the behaviour of the structure - soil system. It enables comparison of various construction variants at the design stage and selection of the best solution in given soil and water conditions for the set selection criteria.

Abstract

A retaining wall is built to provide support to the soil when there is a change in elevation of the ground. Weep holes present in the retaining wall help water to seep through it. Filter protection should be made behind the weep holes to prevent soil erosion around the weep holes. The classic filter material that is widely used is gravel, which is packed according to Hudson’s law. Laboratory experiments were conducted to understand the seepage function of alternative material such as crumb rubber and geocomposite (fabricated) in a homogenous sand layer and in-situ soil. The time taken by the water to reach the weep holes was calculated and compared. From the results, it is suggested to use crumb rubber as an alternative packing material behind the weep hole.