Influência da excentricidade das estacas e da interação bloco-solo no comportamento de fundação composto por treze estacas

Abstract

Executive eccentricities in foundation piles are frequent errors in engineering works and are accounted for in the Brazilian foundation standard. In the case of blocks with misaligned piles, the standard specifies that the forces on the piles must be checked, allowing, without the need for correction or additional effort, an increase of up to 10% in the axial design load of the pile. For greater deviations, a structural verification is required, as the eccentricity may cause load redistributions, altering the interactions between the piles and modifying the structural behavior expected in the design. Based on this, numerical analyses were performed using finite elements, with three-dimensional modeling in Rocscience's RS3 software, to investigate the impact of executive eccentricities on a pile cap supported by thirteen piles, part of the construction of a residential building in Uberlândia (MG). The results of the analyses showed that the eccentricities caused a redistribution of loads among all the piles, overloading some and relieving others. This behavior differed at all loading stages compared to the design, resulting in overloading of the pile group and a reduction in the contribution of cap-soil resistance. In the final stages of loading, little variation in load redistribution was observed, and several piles showed a safety factor below the standard requirements.