Evaluation of service life of reinforced concrete in the middle east eight years of testing

Author(s): Mohamad Nagi, Jessi Meyer, Nizar Marjaba
Paper category: Proceedings
Book title: Proceedings of the International Conference on Sustainable Materials Systems and Structures (SMSS2019) Durability, Monitoring and Repair of Structures
Editor(s): Ana Baričević, Marija Jelčić Rukavina, Domagoj Damjanović, Maurizio Guadagnini
ISBN: 978-2-35158-217-6
e-ISBN: 978-2-35158-218-3
Publisher: RILEM Publications SARL
Publication year: 2019
Pages: 603-610
Total Pages: 848
Language: English

Abstract: A comprehensive long-term study managed by the Middle East Durability Research Consortium (MEDRC) was initiated in March of 2010 to evaluate the service life of reinforced concrete structures in the unique environments of the Middle East, and to correlate these findings to standard testing methodology and service life prediction modeling. It is known that chloride-induced corrosion of reinforcing steel in concrete is the main durability factor controlling the performance and service life of concrete structures in the Middle East, which is considered one of the most corrosive places in the world. Structural design of major structures currently include the durability design required to achieve the specified service life of the structures. Developers and Authorities are demanding 100 years or more for their structures with minimum life cycle cost.
Seventeen concrete mix designs currently used in the region were included in the study. The mixes included different levels of supplementary cementing materials (ground granulated blast furnace slag, fly ash and silica fume) with and without corrosion inhibitor (MCI).
The study consisted of laboratory testing and service life prediction. ASTM G 109 is the main laboratory test considered in the study. Three specimens were prepared in accordance with ASTM G 109 for each of the 17 selected mixes and being monitored at the American University in Dubai Laboratory. This paper presents data on corrosion rates, corrosion potentials and chloride transport levels for the different mixes. It also compares actual results with predictions using available service-life prediction models. In addition, for each mix, the chloride migration and diffusion coefficients were measured at three different ages (28, 56 and 90 days). These parameters are used to verify the service life of each concrete mix using the currently available models. Also these data are used to establish correlation between the rapid migration test and the effective chloride diffusion coefficient. At the end of five year testing, Sulfate resistant cement (SRC) and Ordinary Portland Cement (OPC) specimens with and without MCI were broken open and evaluated.

Online publication :2019
Publication type : full_text
Public price (Euros) : 00