Estudio del estado del hormigón en puentes de 50 años en la región subtropical de Bolivia.

Abstract

The deterioration of concrete is a common factor in structures that are in aggressive environments and are above their useful life, as is the case of old bridges that, additionally, have to withstand higher loads from which they were projected. In this sense, the objective of this article is to analyze the state of concrete in bridges over 50 years in the subtropical region of Chapare - Bolivia, characterized by high humidity and constant rains throughout the year. The methodology of the study consisted of the evaluation of 6 bridges in this region through visual inspections together with field and laboratory tests. Non-destructive tests such as sclerometry, carbonation depth, silver nitrate spray were applied; and destructive tests such as core extraction. The results show that all bridges are negatively affected by the humidity caused by the growth of mosses and vegetation, also facilitates the diffusion of carbon dioxide in the concrete (CO2) allowing the development of carbonation in all cases, chemical process that attacks Slowly and gradually into the concrete until it reaches the steel causing corrosion. The sclerometer results gave a concrete of regular surface resistance, 200 to 300 kg / cm2, which was ratified with the extraction of cores; however, due to the characteristics of these structures, the resistance should be greater.The deterioration and aging of concrete are characteristics related to the nature of the materials; However, the high humidity and lack of inspection and maintenance programs facilitates the development of certain pathological manifestations that compromise the functionality and safety of these structures.