"Laboratory and in-situ testing of gas permeability and self-healing ability of Czech Ca-Mg bentonite"@en . "Bentonite is widely used within construction industry and elsewhere. Due to its very low permeability and high swelling ability the bentonite is used as a sealing barrier in waste sites. Its usage is also envisaged in a deep radioactive waste repository. The waste or the package materials will generate gases within and after the lifetime of these structures; therefore the knowledge of gas migration through the sealing system is essential. The aim of presented research is to experimentally study properties of a Czech Ca-Mg bentonite and thus its suitability for use in construction. Therefore several forms are tested: powder, granules, pellets and their mixtures, or compacted prefabricates. Both in-situ and laboratory experiments are being conducted. All types of these experiments are focused on investigation of bentonite permeability and self-healing ability which are key properties for sealing barriers. The in-situ experiment, situated at the Josef Underground Laboratory, consists of an instrumented horizontal borehole filled by prefabricated bentonite blocks with a perforated steel tube leading through which serves for water or gas injection. Gas injection tests are dedicated to study changes in permeability when increasing saturation of the bentonite filling. Large-scale laboratory experiments are dedicated to test bulk bentonite material. The bentonite is compacted or directly sprayed into a steel cell adapted for material saturation and for implementation of gas injection tests. The results of the testing programme consisting of repeated phases of saturation and gas injection tests for all the experiments show a good self-healing behaviour of the tested bentonite. The variety of performed tests enables to study the effects of different material preparation on the investigated properties and to compare different material forms." . "Laboratory and in-situ testing of gas permeability and self-healing ability of Czech Ca-Mg bentonite"@en . "Smutek, Jan" . . . . "bentonite; gas injection test; saturation; dry density; self-healing; permeability"@en . "RIV/68407700:21110/14:00224462!RIV15-MSM-21110___" . . . "Laboratory and in-situ testing of gas permeability and self-healing ability of Czech Ca-Mg bentonite" . . . . . . . "2"^^ . "RIV/68407700:21110/14:00224462" . "Bentonite is widely used within construction industry and elsewhere. Due to its very low permeability and high swelling ability the bentonite is used as a sealing barrier in waste sites. Its usage is also envisaged in a deep radioactive waste repository. The waste or the package materials will generate gases within and after the lifetime of these structures; therefore the knowledge of gas migration through the sealing system is essential. The aim of presented research is to experimentally study properties of a Czech Ca-Mg bentonite and thus its suitability for use in construction. Therefore several forms are tested: powder, granules, pellets and their mixtures, or compacted prefabricates. Both in-situ and laboratory experiments are being conducted. All types of these experiments are focused on investigation of bentonite permeability and self-healing ability which are key properties for sealing barriers. The in-situ experiment, situated at the Josef Underground Laboratory, consists of an instrumented horizontal borehole filled by prefabricated bentonite blocks with a perforated steel tube leading through which serves for water or gas injection. Gas injection tests are dedicated to study changes in permeability when increasing saturation of the bentonite filling. Large-scale laboratory experiments are dedicated to test bulk bentonite material. The bentonite is compacted or directly sprayed into a steel cell adapted for material saturation and for implementation of gas injection tests. The results of the testing programme consisting of repeated phases of saturation and gas injection tests for all the experiments show a good self-healing behaviour of the tested bentonite. The variety of performed tests enables to study the effects of different material preparation on the investigated properties and to compare different material forms."@en . "S" . . . "[453EE003DEE7]" . . . "http://www.project.conventus.de/fileadmin/media/2014/mecc/Programm/MECC2014_Hpr_WEB_gesamt.pdf" . "21110" . "25521" . "Levorov\u00E1, Mark\u00E9ta" . "Laboratory and in-situ testing of gas permeability and self-healing ability of Czech Ca-Mg bentonite" . . "2"^^ . . .