Service life of reinforced concrete structures made with blended cements and exposed in urban environment

Abstract

Carbonation-induced corrosion is one of the main causes of degradation of reinforced concrete (RC) structures exposed outdoor in urban environment. To prevent steel corrosion, a durability design, that considers both the initiation and the propagation time, is of fundamental importance. At this aim, the resistance to carbonation of concrete and the steel corrosion rate in the exposure environment need to be known. This paper reports the carbonation coefficient and the corrosion rate of 7-day cured RC specimens made with different binders and exposed outdoor in Milan in unsheltered conditions. Corrosion rates in laboratory conditions with different temperatures and relative humidities are also reported. Experimental data were used to evaluate the service life in unsheltered condition. RC specimens made with Portland cement exhibited the lowest carbonation coefficient and corrosion rate, while specimens with 30% limestone and with 70% ground granulated blast furnace slag the highest.

Big milestones in the study of steel corrosion in concrete

“…The work of Luca Bertolini's group is very useful from this point of view. [57][58][59] 4.1 | Preventative methods…”

“…From this point of view, the introduction of performance‐based methods ‐ especially probabilistic ones as Model Code for Service Life Design 56 —is a useful tool, but still requires some care in their application. The work of Luca Bertolini's group is very useful from this point of view 57–59 …”

Geographic division of exposure environment for concrete structure based on fuzzy clustering‐rough set information entropy

“…The level of the air temperature has an obvious impact on the carbonation reaction. 18,19 Relevant experiments show that the carbonation depth of concrete increases with the increase of temperature, following an exponential function relationship. 20 According to Chen et al, different carbonation products are obtained, dependent on the temperature.…”

Diffusion model of sulfate ions in concrete based on pore change of cement mortar and its application in mesoscopic numerical simulation

“…A concrete structure in a corrosive environment inevitably faces the problem of corrosion and deterioration. 1,2 When concrete is corroded, its durability is degraded, shortening the service life of the structure, threatening the safety of the structure, and causing great economic losses. 3 Sulfate is one of the main factors that corrodes concrete.…”

“…Concrete is the most widely used building material in the world because of its economy and good plasticity. A concrete structure in a corrosive environment inevitably faces the problem of corrosion and deterioration 1,2 . When concrete is corroded, its durability is degraded, shortening the service life of the structure, threatening the safety of the structure, and causing great economic losses 3 .…”