Abstract

The present investigation focused on establishing a characterization of public used reinforced concrete constructions such as school units in the coastal zone of Chichiriviche and Tucacas in Venezuela’s Falcon State, exposed to highly corrosive environments and built with inadequate construction techniques. The ultimate aim was to make recommendations to regional bodies so that they could make structural interventions more precisely and assertively. The study was carried out in seven educational units, in which planimetric surveys were carried out, the collection of fault symptoms, tests in some structural members and finally a general evaluation of damages that allowed identifying their durability and particular recommendations for each school building. As a result, these units of different construction ages were in a better state of conservation, when compared directly to the sample evaluated in 2006 in private multifamily buildings, which were even younger than this sample. It was recommended for all cases that they apply a programmed and technical continuous maintenance system, which goes beyond the systems of paints whose substrate is not properly prepared, resulting in a process of superficial repair and aesthetic ineffective.

Abstract

The present research resulted in a standardized laboratory test for the evaluation of properties in a simulated exposure environment by immersion in 3% NaCl solution. The physical and mechanical evaluation was performed on reinforced cylindrical specimens of 30 cm high and 15 cm in diameter, made of concrete with partial replacement of the cement by dose silica in 10% and 15% water cement ratio of 0,45 and 0,65 and design strength of 250 Kgf/cm². Settlement tests, porosity, capillary absorption and mechanical resistance were performed In a period of 5 months, the influence of the substitutions of silica dust in the concrete mixtures with respect to the standard mixtures was analyzed, obtaining an increase in the mechanical resistance with respect to the design, in the ratio a/c 0,45, for the a/c ratio 0,65 reached acceptable values for the substituted mixtures with respect to the mechanical strength compared with the design, as for the porosity and capillary absorption tests were not satisfactory for any relation to a/c probably due to lack of curing prior to exposure.

Abstract