[en] When dealing with long term stability of repository host rocks, it is important to consider and learn from all past geological events since the deposition of the formations. The burial history of the Boom Clay and Ypresian Clays, both considered as potential host rocks in Belgium, illustrates that the North Belgian region was tectonically relatively stable since deposition. In Northern Belgium, where both formations are located at a few hundreds meters of depth, tectonic movements were relatively small and no significant uplifts took place. The burial history of the Boom Clay in Mol, where the HADES underground research facility is located illustrates this. On the poster, the burial history for both formations is presented at two locations each: one location in the outcrop region and one research site location, where the formation is currently buried under a few 100 metres of sediment. (authors)

[en] The aim of present research was to measure and analyze the dynamic changes of internal pressure in shrinking vs. non-shrinking materials during convective drying for the use as a possible process control method. Drying experiments were carried out on wet and fired clay at 50°C and 60°C. In addition, the shrinkage curve was investigated. Experimental measurements show the existence of 4 stages of the process. The comparison of the results for wet and fired clay shows differences in pressure trends. During drying the internal pressure changes from underpressure to overpressure at the level of 3÷5kPa, what correlates well with transition from the first to the second drying period. (Author)

[en] Because of its very low hydraulic conductivity, reducing conditions, slightly alkaline pH, high specific surface, high cation exchange capacity and high plasticity, the Boom Clay is studied as a reference host formation for the deep disposal of high-level long-lived radioactive waste (NIRAS/ONDRAF, 1989). However, Boom Clay also contains up to 5% wt. of organic matter (OM). As radionuclides can form complexes with this organic matter, a detailed characterisation and knowledge of the evolution of the organic matter is necessary. An overview of the characteristics of the organic matter present in Boom Clay is given by Van Geet et al., (2003). The solid phase OM can be up to 5%. The dissolved OM fraction is around 200 mg C per liter of Boom Clay pore water. Both kinds of OM will be discussed. Concerning the solid phase OM the focus will be on the past evolution and its possible future evolution due to a thermal stress. For the dissolved OM, the focus will be on its origin. (author)

[en] In the article we try to validate the reason why the shape of the grains of clay minerals is a useful method for identification

[en] This report describes the prospect ion work for the montmorillonitics clay in the region of Medina swamp in Cerro Largo district. The existence of new deposits was detected by cartography and geological study.

[en] The article presents a comparison of tests carried out on torsional and direct shear devices, in order to determine the strength reduction factor on its contact arising between the soil massif and the underground structure. It is necessary to understand which device makes it possible to determine the strength characteristics that are closest to real cases. For the experiments, soft clay and concrete samples were used. The tests were carried out at a vertical pressure of 100 kPa with speeds of 0,005 mm/min and 0,01196 °/min. According to the obtained results, it was concluded that the values of the shear stresses on the torsional shear device are higher than on the direct shear device. This is due to the fact that the contact area is not constant during the test, respectively, the shear resistance decreases. In a number of other works, the differences in the results are attributed to the fact that the mechanisms of collapse differs depending on the type of device. Therefore, it is necessary to study more detailed the conditions of shear and the process of specimen collapse in all devices, which allow one to determine the strength parameters in order to understand which of them gives more correct results. (paper)

[en] The main objective of the metal corrosion programme is to evaluate candidate container materials for high-level radioactive waste. Electrochemical experiments and immersion tests were performed to complement earlier results from in situ tests in the HADES underground research facility. Values of the critical potentials for localised corrosion were determined by potentiodynamic polarisation experiments as well as to investigate the influence of critical anions

[en] The paper deals with analysis of summary materials on petroleum generation and presented conclusions .The role of radiation and clay in oil formation is shown. It was studied that clay minerals help concentrate organic matter by adsorption and subsequently act as catalyst to generate petroleum. The clay minerals are important compositions in source rocks and reservoir rocks that can generate and store oil and gas respectively. The presence of clay minerals strongly influences the physical and chemical properties of conventional sandstone, carbonate and unconventional shale. For clay minerals in source rocks, they are important for quality evaluation of the hydrocarbon generation, expulsion and migration. Clay minerals help concentrate organic matter by adsorption and subsequently act as catalyst to generate petroleum. The transformation of montmorillonite to illite and increasing ordering of I/S can indicate the hydrocarbon generation and expulsion events

No abstract available

[en] Soil stabilization is an effort to improve engineering properties of soil. The conventional soil stabilization is by adding additives to the soil such as Portland cement, lime, and bitumen. The clay stabilization research was done by adding gypsum and volcanic ash. The research purposes were to find out the value of engineering properties of clay due to the addition of 2% gypsum and 2% - 15% volcanic ash. The soil was classified as Clay – Low Plasticity (CL) based on USCS and was classified as A-7-6 (10) based on AASHTO classification system. The UCT values of original soil and original soil plus 2% gypsum were 1.40 kg/cm² and 1.66 kg/cm² respectively. The CBR soaked and unsoaked values of original soil were 4.44% and 6.28% correspondingly. Meanwhile, CBR soaked and CBR unsoaked values of original soil plus 2% gypsum were 6.74% and 8.02% respectively. The research results showed that the additives materials of gypsum and volcanic ash improved the engineering properties of clay. The UCT result from the stabilized soil by 2% gypsum and 10% volcanic ash gave value of 2.79 kg/cm² (increased 99.28% from original soil). For CBR test, the most effective mixture were in variation of 2% gypsum and 9% volcanic ash which gave value of 9.07% (104.27% increase from original soil) for CBR soaked and 10.29% (63.85% increase from original soil) for CBR unsoaked. The stabilized soil with 2% gypsum and 9% volcanic ash was classified as CL based on USCS and was classified as A-6 (4) based on AASHTO classification system. (paper)