Several structures are built on collapsible soils in the mining and petroleum industries and on civil sites. In order to analyze the stability of such structures, one must properly study the unsaturated soil behavior. Collapsible soils are frequent sand soil that are susceptible to a significant and sudden reduction in volume upon wetting. An important factor is matric suction, which es related to moisture content through the soil water Characteristic Curve (SWCC), the SWCC is obtained through a filter paper technique and provides a valuable relationship between suction and water content unique to soils. This measures the influence of parameters on the behavior of the structure of collapsible soil. Interactions between structure and soil must be properly evaluated as the bearing capacities of shallow and deep foundations are linked to properties of soil suction, moisture, and grade saturation. This work has experimentally measured the parameters of suction and moisture on the behavior of collapsible sands, where an oil storage tank will be built in the city of Lambayeque in Peru. Undisturbed soil specimens obtained from geotechnical exploration campaigns were used. The filter paper method used in this study was that proposed by models of Brooks-Corey and Van Genuchten. Results show consistent values near reported values from literature.