The Individual properties of the selected types of geosynthetics

The paper presents some experimental test results of the influence of selected parameters (samples shapes, short and long creep and relaxation stages, environmental degenerative processes) on the mechanical properties and behaviour of the geosynthetic materials. The individual impact of the change of the above particular parameters on the materials are investigated and some practical conclusions formulated

Influence of Cracks on the Lifetime of Semi-Rigid Pavements

This paper focuses on a better understanding of the process of reflective cracking propagation through the pavement structure. A series of finite element numerical simulations were conducted to investigate the initial stress and strain states in typical semi-rigid pavements with and without reflective cracks under traffic loading. It was assumed that reflective-cracks propagate from the base layer to the pavement surface. The influence of selected parameters, such as the load position, overlay thickness, and subgrade quality on stress and strain concentrations was investigated. The behaviour of the pavement structure under repeated traffic loading was analyzed in terms of ground compaction. The original theoretical model proposed by Prof. Andrzej Sawicki was used to predict the deformation of a pavement subgrade subjected to traffic loading. The damaging effect of cracks appearing in the pavement structure was investigated. It was found that even a single crack in the pavement structure may significantly reduce the pavement lifetime

Assessment of the removal of carbon, nitrogen and phosphorus in municipal wastewater treatment plants in Sokółka

W sytuacji postępującej eutrofizacji wód w wielu krajach zauważalna staje się tendencja do zmiany filozofii podejścia do ich ochrony. Konieczność spełnienia obowiązujących wymagań odnośnie do jakości ścieków oczyszczonych skłania do poszukiwania sposobów intensyfikacji usuwania związków biogennych. W celu zapewnienia żądanego obniżenia stężenia związków biogennych obecnie stosowane są biologiczne metody usuwania azotu oraz biologiczne i chemiczne metody usuwania fosforu.The aim of this study was to show changes in concentrations of organic compounds, nitrogen and phosphorus in wastewater by using activated sludge technology in sequential SBR reactors. Made of raw sewage samples, after mechanical treatment, the dephosphatation, while ¼, ½, ¾, and after complete nitrification, denitrification, and the effluent. Profiles plotted compounds of C, N and P. It has been shown that the sewage treatment plant in Sokółka and increased effects integrated removing the above-mentioned compounds