Reliability Analysis of the Porto Velho Pier - Rio Grande/RS ThroughLimit Equilibrium and Finite Element Method

Abstract

This study analyzes the global stability of the Porto Velho pier, a structure in the port complex of the city of Rio Grande - RS, Brazil. This structure is a gravity pier with a length of 640 m which has been showing excessive displacements in a 150 m stretch. Limit Equilibrium and Finite Element tools associated with the Monte Carlo and FOSM Methods were applied. Four scenarios will be analyzed that represent the evolution of the erosion of the base of the pier structure, in which it can be concluded that as the loss of soil and rockfill of the base occurs, it presents a reduction in the safety factor and according to the FEM results in its rupture. In addition, the FEM analysis shows that the strength criterion of the pier's protective rockfill has a significant influence on the stability of the pier, since when it is considered to be linearly elastic, the structure behaves very similarly to that found by the MEL, while when the Mohr Coulomb criterion is adopted, the structure behaves in a way that is more representative of what is observed in situ.

Keywords

• Porto Velho Pier in the city of Rio Grande - RS
• Stability Analysis
• Seawall
• Reliability Analysis
• Limit Equilibrium Method; Finite Element Method.

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