Previsão de recalques em aterros sanitários utilizando modelos de compressibilidade: estudo de caso da Central de Tratamento de Resíduos de Nova Iguaçu-RJ

Abstract

The present work is about the prediction of long-term Settlement from the field monitoring data in the light of five classical theoretical models, Sowers, Gandolla, Ling, Meruelo and Oweis. The values of the measurements measured during 960 days were used to make a prediction for 50 years, comparing the predicted values expected with the values observed in the surface landmarks. With the monitoring, vertical and horizontal displacements of low magnitude were verified, ranging from 103 mm to 230 mm the vertical displacements and between 0 to 18 mm the horizontal ones, the deformations found ranged from 0.48% to 1.30%. In the comparative analysis of the predictions, the models of Sowers, Ling and Meruelo presented similar behavior despite being conceptually different. For the set of monitored surface landmarks, the setbacks ranged from 160 to 365mm. The three models show a stabilization of the projected settlements from 2000 days, that is, approximately 5 years. Gandolla and Oweis have a remarkable behavior, with predictions of larger repression ranging from 328 to 1085mm, however, the model of Gandolla it presents a stabilization from 8000 days, approximately 22 years and the Oweis model does not reach stabilization even for a period greater than 50 years, a fact that is inconsistent with the geotechnical literature, thus making the model not representative the reality of the studied landfill. From the results found in this research, it was possible to verify that when it is intended to predict future repression and there is little data measured in the field, it is preferable to apply a simpler modeling rather than a more complex one, where it is necessary to adopt parameters that may differ from the particular condition of the site investigated.