Soils in Pereira city are formed by deposits productthe weathering of volcanic ashes that have thick-ness between 6 and 20 m overlying the parent rock;characterization of this material is widely studiedwith respect to its formation process, features andpower of its layers. In this research is made theanalysis of the compression (behavior effort deformationunidimensional) and its relevance withphysical parameters such as liquid limit, specificgravity and unit weight of soil, in different placeson the urban expansion area in the city of Pereira,as an input to the geotechnical knowledge of theseresidual soils.