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The Rock mass is often described as an anisotropic material with several discontinuities within its structure ranging from joints, bedding plans to faulting. In the present study, the effects of infills plasticity on rock mass behavior during failure were investigated. Thus, a series of experiments have been conducted on both soils and cement blocks reconstituted to reflect jointed rock behavior. Different soil materials (obtained by mixing clay and sand) were subject to the cone penetration test and the unconsolidated undrained triaxial test to determine their plasticity index and their unconfined compressive strength. Then, several jointed blocks using the aforementioned soil materials as infill were subject to a uniaxial compression test to assess their maximum stress and investigate their deformation and failure mode. Results showed that stiffer infills would induce a more brittle behavior in the jointed rock while softer infills would instead favor rock deformation and a sharp decrease of its strength. It was also observed that both infill' cross-section and thickness will affect the rock resistance but its deformation will largely be influenced by the later. In the end, some law equations were proposed to draw the mathematical relationship between the jointed rock maximum stress, its deformation at failure and the infill plasticity.

In order to advance the research on using new techniques to produce clean and affordable               energy, many gasification experiments have been conducted on different feedstocks and                      the results have been analyzed. Two promising feedstocks which in the future could help to meet the energy demand are coal and biomass. In this paper, we have collected deep insightful information about the processes of coal and biomass gasification and then compared them. The information contained in this paper cover coal and biomass properties, the devolatization process and the reactions occurring during char gasification. The contrast analysis which has been conducted showed for instance that biomass’ higher atomic ratio (H/C, O/C) was the cause of its lower heating value in comparison to coal; carbon conversion values for biomass was significantly higher compared to coal, and during the gasification process, coal feedstock released significantly higher pollutant gases (like H2S) than biomass. In the end, we also presented some innovative technologies that are now developed in the gasification field and which have proven to be highly efficient.