The water effect on the cyclic mechanical behaviour of a blanket soil layer of an old railway in France

This paper presents a study concerning the influence of water on the mechanical behaviour of a blanket soil layer under a railway structure in France. The soil was mostly created by the natural mixture of ballast and fine particles of the sub-grade. By using a large scale triaxial cell, cyclic tests were performed with a large number of loading cycles at different stress levels. Three water content conditions (w = 4, 6 and 12%) were applied. The experimental results showed the significant effect of the water content on the soil mechanical behaviour. By increasing the water content; the soil specimen axial strain increases and the shear strength decreases.