Consideração da interação solo-estrutura na análise estrutural de edifícios em concreto armado com fundações em estaca: estudo de caso

Abstract

This paper aims to examine the structural behaviour of a 4 story building located in the city of Pato Branco, Paraná, switching the foundation design between rigid and flexible, while comparing support reactions, the columns’ internal loads, global stability parameters and immediate soil settlement for each simulation. The structure’s modeling was performed through the structural design software AltoQi Eberick ™, using drilled pile foundations, totalling 12 meters in depth and cross section diameter assumed to be either 30 or 40 centimeters, according to the pile’s determined load. Attempting to compare the foundation’s settlement parameters, each pile group kept it’s cross section diameter, as well as it’s number of piles, equal between both simulations. The column’s biggest axial load difference between the rigid and flexible foundation simulations observed on a column located close to the structure’s centre, totaling 189.90 kN, which represents a 23.09% gain, while the average reallocation was 46.71 kN, or 11.95 %. The largest relative axial load difference observed to be 35.69 %, or 72.6 kN, on a column located on the structure’s edge. A settlement redistribution was observed on the building’s foundation elements, from those supporting larger loads to those adjacent foundations which were directly connected by beams. The largest differential settlement observed was 1.59 mm on the rigid foundation simulation, and 0.79 mm on the flexible foundation simulation. Horizontal displacements were observed to be larger on the building simulated with flexible foundations, which susequently increased loads for the second order analysis, as well as cross section bending moment on the structure’s columns, implying that the structure’s rigidity diminishes as it’s foundations alternate from rigid to flexible.