The deformation of the unsaturated granular material under the action of long term cyclic loading can be interpreted by unique intrinsic soil properties. The various changes on the soil properties by the application of the cyclic loading creates a unique response to the applied external forces. As the existence of unsaturated soil is predominant, over the saturated or dry soil, the study on the cyclic response of footing over unsaturated soil is an imminent need to understand the response of the structure and to evaluate its performance in the long term.

In this paper, experimental study on the response of the shallow footing resting over multiphase granular soil under the action of cyclic loading is presented. The macroscopic analysis on the evolution of stiffness with the increasing cyclic loops with the change in soil suction is studied. Furthermore the change on the soil response with the increasing number of cycle is studied. From the loops of cyclic loading obtained from experimental results, the stiffness values and the accumulated displacement are computed for different soil suction. The analyzed result provides a strong correlation between the theoretical framework based on small strain principle and soil response in the load displacement domain for multiphase soil under long term cyclic loading. Furthermore a boundary domain for the accumulation of displacement in the suction and cyclic history space is generated.