A Bayesian Approach to Assess the Influence of Coarse Aggregate on the Chloride Test Outcome

Author(s): Naga Pavan Vaddey, Mahmoud Shakouri and David Trejo
Paper category: Proceedings
Book title: Proceedings of International Conferences (ICACMS) Advances in Construction Materials and systems Vol 2
Editor(s): Manu Santhanam, Ravindra Gettu, Radhakrishna G. Pillai, Sunitha K. Nayar
ISBN: 978-2-35158-194-0
e-ISBN: 978-2-35158-191-9
Publisher: RILEM Publications SARL
Publication year: 2017
Pages: 418-427
Total Pages: 10
Language : English

Abstract: Chlorides in concrete can result in premature corrosion of the reinforcement steel and can reduce the service life of reinforced concrete structures. Correctly assessing the initial chloride content requires information on the variation of the chloride concentration distribution throughout the procured samples. Because concrete is a heterogeneous material, understanding how mixture proportions can affect the chloride concentration is important. The present study takes a Bayesian approach to determine how the unbalanced distribution of coarse aggregates in concrete can result in variability in chloride measurements. Concrete specimens were cast with 0.25% admixed chlorides by the weight of cement with coarse aggregates meeting ASTM C33 grade No.67. After curing, specimens were cut at different depths, and the proportions of the coarse aggregates for each layer were determined using quantitative image analysis. Two hierarchical Bayesian models were developed by relating the measured acid-soluble chloride concentration as the response variable to different coarse aggregate size ranges. Results show that the total proportion of coarse aggregate is an influential factor. Increase in coarse aggregate content leads to a reduction in the measured chloride content. The proposed model can be used as a quality control tool for making more informed decisions regarding the expected initial chloride content in fresh concrete. It can also be used to determine the number of samples that are required for a reliable test program.

Online publication : 2017
Publication type : full_text
Public price (Euros) : 0.00