Variation of geotechnical parameters In the mixture of crushed and rounded Gravels in the north west region of Cameroon by the weight mass method

We study the geotechnical parameters (void ratio and hydraulic conductivity) of two types of mixtures of particles (crushed gravel and rounded gravel), and determine the porosity n (or the void ratio e) along with the permeability or hydraulic conductivity by the weight mass method. A progressive evolution of the void ratio of the three granular classes is established starting with completely crushed gravel to the fully rounded gravel. We establish a dependency of the void ratio in function of the size range for each grain size. The study of the permeability or the hydraulic conductivity enables to see a decrease in the evolution of the permeability of different granular classes in function of the shape of the grains. Fully crushed gravels have a higher permeability. We rely on the fact that the values of permeabilities do not follow that of the void ratio and we have established a difference between porosity and drainage which is a function of the stack and grain shape. And then we have established a relationship between the measured values and the predictive values of Chapuis