A consistent method to generate and measure deterioration by corrosion in transverse reinforcements for concrete beams is presented and discussed in this work. This approach could be applied in other circumstances, such as bending, compression or combinations of stresses, with comparable results and therefore can be used to ensure sustainability. In marine environments, macro-cells are produced primarily from a transverse reinforcement, which works as an anode and therefore becomes a critical part of the structural analysis. To evaluate the adaptation efficiency of our proposed method, the corrosion potential, mass losses and cross-section reductions of the steel were measured. The shear stress behavior of the beams was investigated, including beam responses to load deformations, failure modes and cracking. The method ensured that all the beams exhibited a shear failure from diagonal stress with almost 50% less deflection when mechanically tested. The critical cross-sectional area, calculated according to the experimental diameter with the greatest cross-sectional loss due to the corrosion of the deteriorated stirrup, proved to be a reliable value for predicting the ultimate shear strength of concrete beams deteriorated by severe corrosion. A reduction of up to 30% in the shear strength of deteriorated versus non-deteriorated beams was found. Additional results showed that there is a correlation between the experimental and theoretical results and that the method is reproducible.

The passivation process quality was studied considering polarization periodicity, passivation consolidation parameters, and data processing. Passivation process quality in steel reinforcement affects a structure’s planned future service life. Some research has addressed this phenomenon, but its study is complicated by the limits of analog-era data, dispersion in corrosion rate data, and their interpretation. Two series of small reinforced concrete specimens were built using two water/cement ratios and two curing/storage combinations and exposed to the marine environment. Polarization periodicity did not affect passivation/depassivation during passivation but on the data processing. The curing and storage process influenced the tendency towards depassivation. Post-curing storage type affected the cumulative corrosion rate from 1 to 5 μA*day/cm2; this is equivalent to the margin of uncertainty in interpretation.

Durable reinforced concrete is a fundamental requirement in a marine environment, but at the same time it must be sustainable, meaning its production emits the least amount of greenhouse gases. Hence, the importance of achieving optimal proportioning methods. This paper presents and discusses the electrochemical differences in the passivity state of reinforced concrete specimens designed using two proportioning methods: M1 prioritizes the ultimate strength of the element, and M2 focuses on sustainability through optimized aggregate arrangement and reduced cement content. Small beams (150 mm × 150 mm × 300 mm) with varying cover thickness (15 mm, 20 mm, and 30 mm), with two water/cement ratios (0.45 and 0.65), all utilizing Portland composite cement (PCC 30R), were exposed in a tropical marine environment 50 m from the seashore in the north of the Yucatan Peninsula for 700 days (passive state). Corrosion rate, corrosion potential, resistivity, and internal conditions (relative humidity and temperature) were periodically measured. A key finding revealed that M2, despite its sustainable advantage, tends to depassivation before M1, at least during the two years of exposure and while in the passive state.

En este trabajo se presenta el uso práctico del factor de seguridad (FS) en la estrategia de reparación de columnas en un edificio de concreto reforzado con valor histórico (casi 70 años). Se llevó a cabo la reparación del 80% de un edificio ubicado en el centro histórico de la ciudad de Campeche, México, declarado patrimonio de la humanidad por la UNESCO. Se utilizaron estrategias para una mejor utilización de los recursos materiales, equipamiento y mano de obra en la reparación de muros, columnas, losas y trabes. Una de las estrategias fue usar el FS teórico para calcular la profundidad de reparación sin consecuencias estructurales, pero cumpliendo la finalidad de controlar la carbonatación del concreto, y manteniendo la predicción deseada de vida de servicio.

Este trabajo tiene como objetivo evaluar el efecto del método de diseño y del recubrimiento de concreto sobre la correlación entre la resistividad y la velocidad de corrosión. Para ello, se expusieron probetas de concreto reforzado con un diseño volumétrico (M1) y un empaquetamiento de agregados (M2) en un ambiente marino tropical, midiendo periódicamente los parámetros electroquímicos. Los resultados mostraron equivalencia entre ambos métodos cuando se mantuvo el acero en estado pasivo durante el período estudiado. Sin embargo, en los ajustes de la correlación r-icorr se encontró una disparidad: al aumentar el recubrimiento, en M1 el ajuste se alejaba de los modelos teóricos y en M2 se acercaba. Cuando se apliquen modelos, se debe prestar atención a todas las condiciones que involucren al elemento para no sobreestimar la corrosión en etapas iniciales.