Estimativa da vida útil de estrutura de concreto armado imediatamente após sua execução

Abstract

The methods developed to service life prediction of structures in construction are with difficulty hard-working in real works, besides existing in reduced number. The application of these methods would allow the checking of not agreements resulting from the phase of construction after the execution of this, if it used the information on the revetment of the frames, on the quality of the concrete and of the steel, as well as on the dimensions of the sections of the elements. In spite of the difficulty in these methods are applied, it is noticed that that is possible unless the cost of the work is burdened and that other positive consequences, besides the quoted ones above, will appear with their use, like the determination of the structural security of a work while entering in operation, constituting, in this form, an instrument of control. The objective of this work is to apply in constructions a methodology developed by T. J. Da Silva to estimate, after the execution, the service life of reinforced concrete structures, in accordance with the Brazilian Code NBR 6118: (ABNT, 2003), using existing models and methods, associating nondestructive techniques of inspection and methods of structural reliability in a stochastic process. The analyzed construction, a 6 floor building, is located in Uberaba-MG city. In these works, there was done the attendance of all the parts that wrap the structure, I eat it the foundations, the columns, the beams and the slabs. In these elements, the measurements were done of revetment from frames, the attendance of castings, the cures, the control of resistance, besides other tests in laboratory, like the absorption and the test of carbonatação from the concrete in bodies of proof. Analyses in inquiries climatology referring to the mensuration of the temperature, of the relative moisture of the air, of the haste and of the winds of the region in which the works are also were done. There will be still done an inquiry that aims to obtain information on the concentration of CO2 in the local atmosphere. After the formwork retreat, the structural elements were measured. Subsequently to the lifting of all the data, there will be applied the simulation of Monte Carlo and the method of structural reliability (FORM), so that there is defined the function of probability of failure, service life prediction will be defined of the structure through the probability time graph.