Triaxial tests on weak cohesive soils – some practical remarks (Part 1)

• Autorzy: Kowalska M. , Jastrzębska M.
• Języki publikacji: EN

Abstrakty

EN

Standard procedures of triaxial testing recommended e.g. in Eurocode 7 are often unsatisfactory in case of weak cohesive soils (soft and very soft clays, clayey soils with organic content, etc.), mainly due to the high deformability of these soils. Forming a specimen from material sampled in situ and installation of the necessary equipment (a membrane, filter paper strips or on-sample sensors, etc.) may be very difficult and can influence the quality of the test results. This paper (part 1/2) presents detailed description and discussion of the issues related to weak soil sampling and forming of triaxial specimens, based on the Authors’ own experience and literature review. Some solutions, which make the work with weak soils easier and, at the same time, increase the reliability of the results, are suggested e.g.: an “extra consolidation” in a sampler or alternative preparation of the specimen from slurry. Due to the ampleness of the problems related to testing of weak cohesive soils, another issues, such as installation of a triaxial specimen in a chamber or equipping it with different accessories, have been described in part 2 of this paper. In the Authors opinion, the text (parts 1 and 2) may constitute an important hint for researchers completing a triaxial testing system designated for testing weak cohesive soils.

PL

Standardowe procedury badań trójosiowych rekomendowane np. przez Eurocod 7 w przypadku słabych gruntów spoistych (plastyczne i miękkoplastyczne iły, grunty spoiste z zawartością części organicznych itp.) są często niewystarczające. Z powodu znacznej odkształcalności takich gruntów formowanie próbki z materiału pobranego in situ, jak również instalacja niezbędnego wyposażenia takiego jak: membrana, paski filtracyjne oraz czujniki napróbkowe, może sprawiać wiele trudności, zarówno w trakcie wykonywania tych czynności, jak i późniejszej analizy wyników badania. W niniejszym artykule (część 1/2) szczegółowo omówiono i przedyskutowano na podstawie doświadczeń własnych oraz danych dostępnych w literaturze zagadnienia związane z pobieraniem próbek in situ i ich formowaniem do badań laboratoryjnych. Wytypowano rozwiązania ułatwiające pracę z takimi gruntami i zwiększające wiarygodność wyników – m.in. “dokonsolidowanie” gruntu w próbniku lub przygotowania próbki z pasty gruntowej. Ze względu na obszerność problematyki pozostałe zagadnienia (montaż do komory badawczej i instalację czujników) zawarto w części 2. Zdaniem autorek, treść pracy (części 1 i 2) możestanowić istotną wskazówkę dla badaczy kompletujących stanowisko do badań trójosiowych słabych gruntów spoistych.

Słowa kluczowe

EN

sampling; soft clay; triaxial specimen forming; triaxial test; weak cohesive soils

PL

próbkowanie; ił plastyczny; formowanie próbek; badania trójosiowe; słaby grunt spoisty

• Wydawca: Silesian University of Technology
• Czasopismo: Architecture Civil Engineering Environment
• Rocznik: 2016
• Tom: Vol. 9, no. 3
• Strony: 71--80
• Opis fizyczny: Bibliogr. 41 poz.

Twórcy

autor

Kowalska M.

• Faculty of Civil Engineering, Silesian University of Technology, ul. Akademicka 5, 44-100 Gliwice, Poland

autor

Jastrzębska M.

• Faculty of Civil Engineering, Silesian University of Technology, ul. Akademicka 5, 44-100 Gliwice, Poland

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