Existing river valley development methods which have been used for a significant period of time, as well as the use of land for construction of residential developments, have led to negative consequences for the environment. The agricultural use of land and its protection with hydraulic structures has restricted the natural flood area of the river. According to EU law, the risk of catastrophic flooding should be reduced, and its effects minimized. Sustainable water management determines the effectiveness of flood protection in the whole river basin. The paper presents the flood protection on the Odra River in the segment between Nowa Sól and Cigacice, with special emphasis on the possibility of reconstructing the former flood polders in the Middle Odra Region that existed before the year 1945, including the polder in Milsko.

Purpose Winter road maintenance involves the use of various chemical compounds which affect the active capillarity of soils. The main goal of the study was to determine a model to predict changes in the active capillarity of soils using distilled water and water solutions of chemical compounds which are used in winter road maintenance. The purpose of the first part of the experiment was to determine a model to predict changes in the height of capillarity rise and the rate of capillary rise with time. The second part of the experiment investigated how water solutions of selected chemical compounds altered the soils' active capillarity as determined using distilled water. Materials and methods The research was carried out on three soils from deposits in west-central Poland, and their separated fractions. Active capillarity was investigated with the use of distilled water and 5 and 10 % solutions of ten chemical compounds used in winter road maintenance. The rate and height of capillary rise were measured in transparent vertical tubes, placed vertically in a glass tank into which the distilled water or solutions of chemical compounds were poured. Results and discussion The rate of capillary rise was decreasing as a function of time. After the first part of the experiment had been completed, an analysis was made of the statistical fit between the experimental data for capillary rise of distilled water in the studied soils and soil fractions, and the model described by the formula hðtÞ ¼ h 1 þ v 1 Â lnðtÞ, where h 1 denoted the height of capillary rise in the first second, v 1 denoted the rate of capillary rise, and t denoted time. High determination coefficients indicated a good fit of the model to the experimental data. In the second part of the study, it was found that solutions of chemical compounds caused a reduction in the active capillarity of the studied soils relative to the capillarity determined using distilled water. It was possible to determine a capillarity coefficient w k so as to compare the capillary rises in soil of distilled water and of the various chemical compounds in 5 and 10 % solution. Analysis of the results showed that the capillarity coefficient w k is a characteristic feature which depends on the type and concentration of the chemical subject to capillary action and on the type and fraction of soil.Conclusions The active capillarity of soil depends on the type and concentration of the capillary fluid such as distilled water or water solutions of chemical compounds used in winter road maintenance and other factors. The relation between the height of capillary rise h and time t can be described using the formula hðtÞ ¼ h 1 þ v 1 Â lnðtÞ. The water solutions of chemical compounds used in winter road maintenance caused a reduction in the active capillarity of the studied soils relative to the capillarity determined using distilled water. It was found that the susceptibility of soil to capillary rise can be determined based on the capillarity coefficient w k . This coefficient depends on the ty...

The process of the construction of engineering structures situated within glacitectonically disturbed areas cause the necessity to link engineering operation with knowledge of geological processes. One of the examples of such a structure was the construction of the west bypass of Zielona Góra. The roadworks were connected with the necessity of deep excavations into glacitectonically disturbed soil structures. This caused intense changes in the soil mass and - as a consequence - loss of slope stability and the construction of landslides. At the construction stage numerous landslides were already active, which additionally increased during intensive road use. In spite of technical stabilization, there was a risk of loss of slope stability, which is a consequence of stresses in soil mass and engineering activity. This article presents the results of the monitoring of the slope stability during intensive road exploitation.

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Streszczenie Popiół lotny j est odpadem produkcyjnym, wytwarzanym w wyniku spalania węgla w kotłach energetycznych. Rocznie na świecie wytwarza się miliony ton tego odpadu, stąd niezwykle ważne jest umiejętne jego zagospodarowanie, w tym - uzyskanie materiału o wyższej jakości niż zastosowany produkt wyjściowy. Celem pracy jest określenie przydatności przetworzonych popiołów lotnych z węgla brunatnego do wzmocnienia (stabilizacji) gruntów stosowanych w budowie nasypów drogowych oraz podbudowy dróg. Wyniki pracy są sposobem na utylizację odpadów, a jednocześnie - uzyskanie nowych materiałów i technologii w budowie obiektów liniowych. Jest to zagadnienie istotne zarówno z punktu widzenia ochrony środowiska przyrodniczego, jak i pozytywnego wpływu przetworzonych popiołów lotnych na trwałość obiektów drogowych. W pracy przedstawiono wyniki badań przeprowadzonych na popiołach lotnych z węgla brunatnego wytwarzanych w Elektrowni Pątnów. Popioły te zostały najpierw zmodyfikowane (aktywowane) za pomocą „aktywatora magnetycznego Wapeco”, a następnie - użyte do wytworzenia spoiw hydraulicznych (z dodatkiem cementu) oraz mieszanek gruntowo-spoiwowych. Poszczególne mieszanki sporządzono na bazie surowców mineralnych zalegających w siedmiu różnych złożach regionu lubuskiego (zachodnia Polska). Zastabilizowano je dwoma spoiwami hydraulicznymi (o wytrzymałości 3 i 9 MPa), przy zróżnicowanym dodatku spoiwa hydraulicznego (6% i 8% w stosunku do masy gruntu). Podczas badań określono przyrost wytrzymałości badanych próbek (po upływie czasu: 14,28 i 42 dni) orazprzyrostwskaźnikanośności (bezpośrednio po zagęszczeniuipo 7 dniach). Interpretacja wyników badań pozwoliła na ocenę dynamiki wzrostu wytrzymałości na ściskanie i nośności różnych gruntów zastabilizowanych spoiwami hydraulicznymi, wytworzonymi na bazie popiołu lotnego z węgla brunatnego, oraz - wskazanie możliwości zastosowania tych materiałów. Przeprowadzona analiza wykazała, że istnieje możliwość wzmocnienia gruntów za pomocą tych spoiw, a następnie - zaliczenia gruntów uznawanych dotychczas za słabonośne (tj. piaski gliniaste, pospółki gliniaste, gliny) do materiałów w pełni przydatnych w budownictwie drogowym.