Kazimierz Garbulewski

Selection of material suitable for permeable reactive barriers in the vicinity of landfills

Selection of material suitable for permeable reactive barriers in the vicinity of landfills This paper focuses on the criteria proposed for the selection of reactive materials suitable for permeable reactive barriers surrounding waste disposal sites. The criteria were divided into three groups: hydraulic, mechanical and sorption. Hydraulic and sorption criteria are equivalents and complementary to one another in the process of reactive material selection. Only a material that fulfills both criteria should be used. The third criterion — mechanical — that is related to the deformation and strength properties of the reactive material should be considered in designing the technology and evaluation of safety conditions. Kryteria doboru materiałów do wykonania przepuszczalnych barier reaktywnych (PBR) w rejonie składowisk odpadów. W artykule przedstawiono kryteria, które są konieczne do wybrania, zależnie od lokalnych warunków środowiskowych i geologicznych, odpowiedniego materiału do wykonania PBR w rejonie składowisk odpadów. Kryteria doboru materiałów obejmują trzy aspekty: hydrauliczny, sorpcyjny i mechaniczny (właściwości wytrzymałościowe i odkształceniowe). Kryteria hydrauliczne i sorpcyjne są równoważne i uzupełniające się przy wyborze odpowiedniego materiału reaktywnego. Optymalnym materiałem jest ten, który równocześnie spełnia oba kryteria. Kryterium trzecie — mechaniczne — powinno być wzięte pod uwagę w projektowaniu technologii i określeniu niezawodności PBR.

Advantage of Bayesian approach to geotechnical designing

Advantage of Bayesian approach to geotechnical designing The paper addresses the possibility of the Bayesian approachs application to geotechnical engineering. First the principal information on the Bayesian analysis has been presented and its applications to estimate the soil parameters based on the CPT/DMT tests at SGGW Campus in Warsaw afterwards. The CPT/DMT tests had been carried out in order to recognize the geotechnical conditions in the foundations of design campus buildings. The data from two layers of glacial boulder clays have been analysed. The results demonstrate that the Bayesian approach is a useful tool in evaluation of ground properties and estimation of the geotechnical parameters in specified circumstances. Zalety wnioskowania bayesowskiego w projektowaniu geotechnicznym Artykuł przedstawia zalety stosowania podejścia bayesowskiego do projektowania geotechnicznego. W pierwszej części artykułu przedstawiono zasadnicze założenia analizy bayesowskiej i opisano przykłady jej zastosowania w ocenie warunków geotechnicznych posadowienia budowli i doboru parametrów w projektowaniu geotechnicznym. Do obliczeń projektowych Autorzy wykorzystali wyniki badań CPT i DMT przeprowadzone na terenie Kampusu SGGW w Warszawie. Dane z badań dwóch warstw geotechnicznych (glin zwałowych) zostały wykorzystane do określenia wartości charakterystycznych wybranych parametrów geotechnicznych. Analiza statystyczna z zastosowaniem podejścia bayesowskiego doprowadziła do średnich wartości qc na poziomie ufności 0,95 które wynoszą dla warstwy III i IV odpowiednio: (10,463, 11,934) MPa i (7,883, 8,6995) MPa. Z analizy danych dylatometrycznych wynika, że średnie wartości parametru KD w warstwie III i IV wynoszą odpowiednio: (23,015, 24,11) i (13,48; 13,89). Wyniki analiz pokazują, że podejście bayesowskie w pewnych sytuacjach może być wykorzystane do oceny właściwości podłoża i określenia parametrów geotechnicznych.

Strength and deformation parameters of boulder clay to design of buildings at the margin of a moraine plateau in Warsaw

Abstract The selection of soil parameters suitable to the geotechnical design calculations is regarded widely as one of the most important and simultaneously difficult engineering task, which according to the Eurocode 7 standards should be undertaken into distinct three steps. The second of these steps, namely obtaining the characteristic values requires a careful and a cautions estimation with application of the statistical methods even by using a Bayesian approach as shown in this paper. This paper presents the process of selecting a characteristic strength and deformation parameters from CPT and DMT investigation for boulder clays discovered at the margin of a moraine plateau in Warsaw. This layer was chosen for foundations of design academic buildings. In the selection of the characteristic parameters with application of the numerical program BAYANAL the spatial distribution of strength and deformation properties was taken into account. Particular attention was focused to the affect resulting from in situ test locations at different distances from the design facilities. Finally, the remark conclusions were presented including opinion on the role of aims and spacing of investigation points in geotechnical designing.

Geomorphological analysis in soil profile assessment of the margin of Warsaw morainic plateau in Ursynów

Abstract This paper addresses the application of geomorphological analysis to recognize the geotechnical conditions at the margin of a moraine plateau in Warsaw. Aerial photographs, borehole data logging, CPT and DMT tests results were taken into account to compare the conditions at two sites, i.e. the well recognized part of the moraine plateau (SGGW Stadium site) and the second part located at a distance of 5 km (Warsaw slope – church). Spatial variability of the strength and deformation properties in the study areas were determined using CPT and DMT tests results. The general conclusion is that the specific geomorphological units allow for prediction to some extent the sequence of geotechnical layers and the general distribution of soil parameters. The example from the margin of the moraine plateau in Warsaw shows that such procedure is a promising statistical tool related to geotechnical problems.

Prediction of free field heave using CW and CH indices

Abstract Prediction of free field heave using CW and CH indices. In order to predict free heave in expansive silty clays two methods were applied: CLOD test and double-swelling methods. In both methods CW and CH indices are required respectively to determine the soil heave. The CW index is determined as a slope of straight line of shrinkage curve obtained with a use of CLOD test. In case of double-swelling method two oedometer tests were carried out to determine CH index: constantvolume and consolidation-swell oedometer tests. Comparison between heave values calculated using CW and CH indexes indicated slight differences.

Reactivity of nano zero-valent iron in permeable reactive barriers

Abstract In this paper, the ability of nZVI to remove heavy metals (Cd, Cu, Ni, Pb, Zn) from multicomponent aqueous solutions was investigated through batch experiments. The experimental data were fitted to a second-order kinetic model based on solid capacity. The data for copper and lead fitted well into the second-order kinetic model, thus suggesting that the adsorption had a physical character. The values of the removal ratio and the second-order rate constant indicated that the order of adsorption priority of nZVI was as follows: Pb>Cu>Zn>Cd>Ni. The adsorption isotherm data were described by the most conventional models (Henry, Freundlich, and Langmuir). Equilibrium tests showed that copper and zinc were removed from the solution by adsorption processes, i.e., complexation and competitive adsorption. The test results suggested that the removal processes using nZVI are more kinetic than equilibrium. The study demonstrated that nZVI is favorable reactive material; however, comprehensive investigation should be performed for further in situ applications in PRB technology.

BAYANAL code in geotechnical design based on Eurocode 7

Abstract BAYANAL code in geotechnical design based on Eurocode 7. Geotechnical problems that are characterized by a high degree of complexity and uncertainty with respect to the input data are solved recently, using the Bayesian analysis (for instance the problem of a cautious estimation of the geotechnical characteristic parameters according to the Eurocode 7 requirements). The applicability of the Bayesian approach to geotechnics via a simple examples related to determination of characteristic values of geotechnical parameters for design structures is in the paper addressed. In order to select the characteristic parameters for the geotechnical design a new numerical code called BAYANAL was developed. Example of applying the BAYANAL code to analyse the DMT tests demonstrates that it is a powerful and promising tool in evaluation of ground properties and geotechnical parameters. Streszczenie Program BAYANAL w projektowaniu geotechnicznym według Eurokodu 7. W projektowaniu geotechnicznym według Eurokodu 7 przy określaniu wartości charakterystycz nych parametrów geotechnicznych, w tym wytrzymałościowych i odkształceniowych, należy w sposób ostrożny i przemyślany zastosować metody statystyczne, zarówno klasyczne, jak i tzw. bayesowskie. Analiza statystyczna Bayesa uzasadniona jest w przypadku posiadania i uwzględniania w doborze parametrów wartości a priori, na przykład wartości eksperckich parametrów geotechnicznych, lub w przypadku możliwości powiększania liczebności zbiorów parametrów i danych geotechnicznych, co stanowi podstawę projektowania metodą „obserwacyjną”. Do analizy statystycznej danych geotechnicznych zastosowano numeryczny pakiet BAYANAL. Pakiet BAYANAL może znaleźć szerokie zastosowanie w praktyce projektowania geotechnicznego w Polsce do doboru parametrów geotechnicznych miarodajnych do projektowania bezpiecznych obiektów budowlanych

SASK method for testing hydraulic conductivity of soils by flat dilatometer (DMT)

Abstract DMT is one of the most popular methods of determining soil parameters needed to design a safe construction. Apart from the basic outcome parameter obtained from DMT measurements hydraulic conductivity (k) can be determined, previously proposed DMTA and DMTC methods were modified. The basic idea of the method is that the return of the deformed membrane is due to soil and water pressure. In the proposed SASK method the hydraulic conductivity of the soil is determined by measuring time-varying pressures A and C. Research has been performed at the experimental site of the Department of Geotechnical Engineering, WULS. In the paper, the assumptions of the new method for determining the hydraulic conductivity k are presented. The proposed method allows us to determine a reliable value for the hydraulic conductivity of clay soils. Using this method, the value of hydraulic conductivity (k = 5,47*10-11) is similar to the results of BAT, DMTA and laboratory measurements.