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<div class="section abstract"><div class="htmlview paragraph">Road mobility is evolving driven by environmental and energy constraints. The pursuit of cleaner and more efficient drivetrain systems has resulted in significant R&amp;D work in the areas of fuels, engine efficiency, and pollutant control. It is essential to reduce the environmental impacts of internal combustion engines due to the overwhelming presence of vehicles equipped with these engines in today’s fleet, so the need to develop fuels with the potential to significantly reduce CO₂ emissions is obvious. The main objective of this work is to understand the behavioral effects in the engine when fueled with different biofuel percentages blended in conventional diesel (B7, B15 and HVO15). This was accomplished by several experimental tests carried out on a dynamometer using a vehicle equipped with a common-rail Diesel engine, considering performance analysis (power and torque) and WLTP cycles to realize fuel consumption and emission data. Additionally, to understand the way the engine perceives the use of different fuels the in-chamber pressure and the fuel injector behavior were measured, considering different load and engine speed conditions. It was observed that B7 was the most efficient fuel, presenting fuel consumption values of 5.94 kg/100km, lower than 6.10 kg/100km for HVO15 and 5.99kg/100km for B15. The differences in performance for B7 and HVO15 were almost unnoticeable. Nevertheless, some consistent differences in injector opening times and in-cylinder pressure were noted, which supports the observed engine performance and efficiency results, allowing to detect the relation of engine adaptation to different fuel properties, its energetic and environmental effects.</div></div>

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The paper reports laboratory investigations carried out in granitic residual soil from Covilha, to evaluate the stress-strain-dilatancy behaviour to provide a new model. Some soil tests are intended only to classify soil into broad groups. Other tests are done to examine the mechanical behaviour of soils and particularly to investigate their strength and deformation during loading. Drained and undrained triaxial tests were performed to study soil fabric effects on the mechanical behaviour of a granitic residual soil. It was revealed that the dilatancy of the saturated soil contributes to shear stress and strength at lower confining pressures. The cohesion is apparent for small stress and we need to introduce the evaluation of volumetric strain to understand the effect of the dilatancy in the peak strength.