PSI - Issue 17

Available online at www.sciencedirect.com Structural Int grity Procedia 00 (2019) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000 Available online at www.sciencedirect.com ScienceDirect

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 17 (2019) 80–89

ICSI 2019 The 3rd International Conference on Structural Integrity Evaluation of damage in concrete from structures affected by internal swelling reactions – A case study João Custódio*, António Bettencourt Ribeiro LNEC – National Laboratory for Civil Engineering, Avenida do Brasil, 101, 1700-066 Lisboa, Portugal Nowadays, a significant number of concrete infrastructures are affected by internal swelling reactions (ISR). The most common in Portugal are the alkali-silica reaction (ASR) and the internal sulphate reaction (DEF). Existing knowledge does not allow for a complete assessment of the actual condition of an ISR-affected structure and an accurate prediction of the mechanical properties deterioration and, consequently, of the period during which the structure will effectively perform its function. To help surpassing this situation, research is being conducted at LNEC to contribute to the establishment of a method for a more accurate determination of the current level of ISR progression and of the deterioration of the concrete mechanical properties. This paper aims at contributing to the ongoing discussion of this topic and, therefore, presents the methodology followed to assess the condition of the concrete from an ISR-affected motorway underpass in Portugal. It includes a comprehensive experimental campaign, performed to concrete cores, to allow for an adequate diagnosis and prognosis of the ISR development. The results evidenced the utility of such a methodology on the appraisal of the actual expansion level attained to date in concrete from ISR-affected structures. ICSI 2019 The 3rd International Conference on Structural Integrity Evaluation of damage in concrete from structures affected by internal swelling reactions – A case study João Custódio*, António Bettencourt Ribeiro LNEC – National Laboratory for Civil Engineering, Avenida do Brasil, 101, 1700-066 Lisboa, Portugal Abstract Nowadays, a significant numb r of concrete infrastructures are affected by internal swelling reactio s (ISR). The most common in P rtugal are the alkali-silica reaction (ASR) and the internal sulphate reaction (DEF). Existing knowledge does ot allow for a complete assessment of th actual condition of an ISR-affected str cture and an accurate prediction of the mechanical properties deterior ti and, conseque tly, of the period during which th structure will eff ctively perf rm its function. To help surpassing this situation, research is being c nducted at LNEC to contribute t the establishment of a method for a more accurate det rmination of the current level of ISR progression and f the eterioration of the concrete mechanical properties. This paper aims at contributing to the ongoing discussion of this topic and, therefore, presents the methodology followed to assess the condition of the concrete from an ISR-affected motorway underpass in Portugal. It includes a comprehensive experimental campaign, performed to concrete cores, to allow for an adequat diagnosis and prognosis of the ISR devel pment. The results evidenced the utility of such a methodology on the appraisal of the actual expansion level attained to date in concrete from ISR-affected structures. Abstract

© 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers.

Keywords: Internal swelling reactions; concrete; alkali-silica reaction; delayed ettringite formation; diagnosis; prognosis Keywords: Internal swelling reactions; concrete; alkali-silica reaction; delayed ettringite formation; diagnosis; prognosis

1. Introduction 1. Introduction

Currently, a significant number of concrete infrastructures, in Portugal and throughout the world, are affected by internal swelling reactions (ISR). Among the various reactions that can cause concrete swelling, the most common in Portugal are the alkali-silica reaction (ASR) and the internal sulphate reaction (term hereinafter used to designate the Currently, a significant number of concrete infrastructures, in Portugal and throughout the world, are affected by internal swelling reactions (ISR). Among the various reactions that can cause concrete swelling, the most common in Portugal are the alkali-silica reaction (ASR) and the internal sulphate reaction (term hereinafter used to designate the

2452-3216 © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. 2452-3216 © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. * Correspon ing author. Tel.: +351 218443246; fax: +351 218443023. E-mail address: jcustodio@lnec.pt * Corresponding author. Tel.: +351 218443246; fax: +351 218443023. E-mail address: jcustodio@lnec.pt

2452-3216  2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. 10.1016/j.prostr.2019.08.012