The safe operation of the large, outflow Tailings Storage Facilities (TSF) requires comprehensive and continuous threat monitoring. One of the basic kinds of threat monitoring is to monitor the water conditions in deposited tailings, which is usually carried out using a conventional piezometric observation method from a network of installed piezometers. In complex tailings storage conditions, the reliability of the piezometric method may be questioned. The Seismic Cone Penetration Test (SCPTU) can meet high test standards. The results of the penetration tests closely identify conditions of sediments that determine the tailings water regime verified locally on the basis of pore water pressure dissipation tests. On the other hand, seismic measurements perfectly complement the characteristics of sediments in terms of their saturation. The analysis of the results of SCPTU implemented in the tailings massif also showed that below the phreatic surface, a zone of not fully saturated tailings can be found. Its presence improves the stability conditions of the tailings massif and dams, but also limits the possibility of the static liquefaction of tailings.

Tschuschke, W., Kumor, M.K., Walczak, M., Tschuschke, M., 2015. Cone pen e tra tion test in as sess ment of soil stiff ness. Geo log i cal Quar terly, 59 (2): 419-425, doi: 10.7306/gq.1188The pa per pres ents pro pos als for the as sess ment of sub soil stiff ness based on re sults of the seis mic cone pen e tra tion test. Cor re la tions be tween pen e tra tion pa ram e ters and con strained modulus were de ter mined for three ge net i cally dif fer ent groups of co he sive soils. For the ana lysed soil ma te rial, quan ti ta tive es ti ma tion was also con ducted for the pa ram e ter de termin ing the re la tion ship be tween the con strained modulus and ini tial shear modulus. A marked trend was shown for this param e ter with the soil be hav iour type in dex used in the clas si fi ca tion of soils in the cone pen e tra tion test.

Streszczenie. Analizowano straty filtracyjne wzdłuż około 80-kilometrowego odcinka rzeki, powstałe w wyniku spiętrzenia wody w rzece Warcie wywołanego zrzutami ze zbiornika retencyjnego Jeziorsko realizowanymi w celu zapewnienia przepływów niżówkowych (minimalnych) Warty. Przeanalizowano 12 hipotetycznych przebiegów fali w zależności od wielkości i czasu trwania zrzutu. Parametry określające właściwości filtracyjne podłoża wyznaczono na podstawie badań terenowych przeprowadzonych na terenie polderu Majdany, w przekroju znajdującym się w połowie analizowanego odcinka rzeki. Wyznaczono skumulowane wydatki filtracyjne, będące sumą strat, oraz chwilowe wydatki przez dno koryta rzeki. Straty porównano z objętościami zrzutów w poszczegól-nych symulacjach. Wykazano iż straty na rozpatrywanym odcinku nie są duże i sięgają maksymalnie 1,3% objętości zrzutu a udział procentowy maleje wraz ze zwiększaniem się wielkości zrzutu oraz czasem jego trwania. Rozwiązania uzyskano z wykorzystaniem MES zaimplementowanej w pakiecie oprogramowania komputerowego Hydrus, umożli-wiającego analizowanie zagadnień niestacjonarnych ze zmiennymi w czasie warunkami brzegowymi.Słowa kluczowe: filtracja z koryta rzeki, straty filtracyjne, MES, Hydrus, zmienne w czasie warunki brzegowe

No abstract

Seismic tests are becoming more and more meaningful in modern geoengineering since they allow precise assessment of changes in the analyzed profile of soil deformation parameters at very small strain. The engineering practice generally uses two methods for such kinds of tests: reference cross-hole test and commercial down-hole method. The costs of implementation of this kind of research and the reliability of the results obtained along with any additional benefits from the type of the selected testing technique are not without significance. Seismic measurements for which comparative analysis was performed were carried out in a strongly anisotropic materials base of a tailings. The results of tests conducted with a standard cross-hole method were compared with those conducted using the down-hole method, in which the seismic piezocone (SCPTU) and seismic dilatometer (SDMT) were used. Test results have shown that in terms of assessment of their credibility, there were no fundamental differences in the quality of the recorded signals. It has been pointed out, however, that there are many advantages to penetration in situ tests, which complement identification of subsoil structure with many crucial elements that cannot be achieved using the cross-hole method.