Reliability‐based recommendations for EN1992 carbonation cover design of concrete with coarse recycled concrete aggregates. (18th March 2022)

• Record Type: Journal Article
• Authors: Albuquerque, António; Pacheco, João; de Brito, Jorge
• Is Part Of: Structural concrete. Volume 23:Number 3(2022)
• Page Start: 1873
• Page End: 1889
• Publication Date: 2022-03-18
• Subjects: carbonation -- concrete cover design -- Eurocode 2 -- fib Bulletin 34 -- recycled aggregate concrete -- reliability analysis; Reinforced concrete -- Periodicals; 624.1834
• DOI: 10.1002/suco.202100406
• Languages: English
• ISSNs: 1464-4177

Abstract

Abstract: Research argues in favor of using recycled aggregates in structural concrete. However, lack of specific clauses in standards for recycled aggregate concrete design hinders the use of recycled aggregate concrete by the industry. Recycled aggregate concrete‐specific design clauses are hindered because conventional research must be complemented with experiments directed towards stochastic modeling, so that reliability concepts may evaluate whether the probabilities of failure of design comply with the expectations of Society or whether specific design rules are needed. This article compares the within‐batch variability of carbonation under accelerated conditions of four natural aggregate concrete and four analogue recycled aggregate concrete mixes and analyses the reliability of Eurocode 2 cover design for carbonation exposure. In general, the incorporation of coarse recycled concrete aggregates worsened the mean durability behavior of concrete, including resistance to carbonation. However, the variability of carbonation depth was not meaningfully affected by the recycled aggregates used (coarse recycled aggregates produced from concrete waste) and the reliability of concrete cover design only decreased due to the effect of the recycled aggregates on the mean resistance to carbonation. A 5 mm increase of concrete cover was found to more than offset the detrimental influence of full incorporation of recycled aggregates on the reliability of concrete cover design.