The main aim of this paper was to approximate displacement of subgrade surface under cyclic loading. Soil specimens were loaded by force, which caused displacement to 2.54 mm. After that, specimens were loaded by the same force a number times. This procedure allowed to define the kind of displacement occurring under cyclic loading. An analysis of individual displacement was done on paper. Soil specimen was sandy clay and sandy clay stabilized by the addition of lime, the amount of which equals 8%. The additional aim was to prove that stabilization of cohesive soils with lime can marked increase stiffness of soil and to show various load-unload conditions of stabilized and non-stabilized sandy clay.
Design of road pavement is connected with estimation of mechanical properties of each of the materials used for construction. This statement presents the need of estimating the mechanical moduli. For the purposes of this article, tests were carried out in order to establish physical and mechanical properties, especially penetrating resistance CBR. The main aim of this paper was to estimate the optimal lime and water content in soil – clayey sand. The paper presents the expected cyclic behavior of clayey sand, as well as method for calculating the resilient modulus (Mr).