Aproximación de la capacidad portante de un suelo tipo conglomerado de la ciudad de Cuenca

Abstract

This research deals with the analysis of the mechanical behavior of a conglomerate soil belonging to the Qt5 fluvioglaciar terrace in the city of Cuenca. The conglomerate soil is characterized by presenting a wide granulometric distribution that ranges from large blocks of rock to fine clay material that makes up the matrix in which the blocks are immersed. In this study, the mechanical characterization of the material is represented by the parameters of shear resistance: angle of internal friction (ɸ) and cohesion (c), which have been estimated through the application of empirical relationships and the execution of field tests. For the application of the first methodology it is necessary to perform the physical characterization of the conglomerate, determining properties such as the particle size distribution, relative density and dry specific weight, which, through of the empirical correlations considered, allow the estimation of the friction angle whose value ranges between 35° to 55°. In the field, 4 direct shear tests were carried out on an unaltered sample with a cutting area of 0.64 m², in order to obtain normal and shear stresses and build a failure envelope thus achieving a ɸ=55° and c=0.12 kg/cm² A geophysical prospecting test was also carried out, from which the shear and compression wave velocities are obtained which, through the use of correlations, allow the estimation of various mechanical parameters of the soil and its bearing capacity; through a back analysis process a value of ɸ=31° and c=0.15kg/cm² are obtained. Finally, the results of shear resistance obtained from the different methodologies are compared and used to estimate the bearing capacity of the soil for each case.