Estacas embutidas em rocha, análise de métodos de dimensionamento.

Abstract

This study presents an analysis of pile design in rocky terrains, focusing on the limitations of methods commonly used in Brazil for structures embedded in rock. Recognizing the need for methodologies that more accurately consider the specificities of rock materials, three approaches were applied: the traditional method of Cabral and Antunes, the method of Cabral and Antunes adapted by the Rock Quality Designation (RQD) index, based on the methodology of Peck et al., and the method of O'Neill and Reese, also adapted according to the methodology of Peck et al. To improve accuracy, the Cabral and Antunes method was adjusted to include the RQD index, in accordance with the Peck et al. methodology, allowing for the consideration of variation in the resistance of the rock mass meter by meter. This approach provides a more detailed analysis of the soil-rock interaction. Similarly, the O'Neill and Reese method was adapted using the concept of Peak et al., considering the greater accessibility of the RQD test compared to complete rock characterization. The results indicated that the adapted O'Neill and Reese method was the one that most closely matched the pile test results. On the other hand, the adapted Cabral and Antunes method provided satisfactory results in one of the cases analyzed, offering accuracy and safety, but in another case, it revealed limitations, being unfavorable in terms of safety. The comparison between the methods shows that the use of field parameters such as RQD provides greater accuracy and safety in resistance estimates, making it a more reliable alternative to the traditional method. It is concluded that integrating specific geotechnical parameters, such as RQD, into design methodologies can result in significant improvements in safety and cost-effectiveness for foundations in rocky terrains in Brazil. These methodological adaptations serve as the basis for the development of more advanced practices in foundation engineering, contributing to the evolution and efficiency of structural projects in challenging geotechnical conditions