Avaliação do efeito da eficiência das sondagens à percussão na previsão de capacidade de carga e recalque de estacas pré-moldadas

Abstract

In building projects, foundations must meet project requirements to ensure the safety of the work. Therefore, estimates of load capacity and foundation settlements are necessary. It is usual to make these estimates based on the results of field trials. The present work proposes an evaluation of the predictions of load capacity and settlements of foundations on precast piles using semi-empirical and theoretical methods based on the results of percussion sounding (SPT), with and without consideration of the test efficiency correction. To this end, seven piles were analyzed, manufactured in reinforced concrete, and driven into typical soil profiles of the Metropolitan Region of Fortaleza (RMF). For the proposed evaluation, the results of load tests and SPT surveys were used. The predictions estimated by semi-empirical and theoretical methods were compared to the values obtained experimentally through load tests. The load capacity and settlement predictions were made without correcting the sounding efficiency and for an efficiency of 70%. Considering the correction of the efficiency of SPT soundings, both in load capacity and settlement calculations, promoted more consistent predictions for almost all situations analyzed.