Surface corrosion in uncracked high performance steel fibre reinforced cementitious composites

Mylene De Melo Vieira,Sergio H P Cavalaroc,Antonio Aguado

doi:10.47842/juts.v4i1.28

Abstract

High-performance steel fibre reinforced cementitious composites (HPSFRCCs) are usually produced with high contents of steel fibres. Therefore, more fibres are expected close to the surface. Despite the very dense matrix of these materials, the ingress of detrimental agents such as chlorides may occur. The objective of this work is to evaluate the mechanisms and effects of corrosion in HPSFRCCs specimens in terms of surface aspect. Eight mixes of HPSFRCCs with different fibre content (40, 80, 120 and 160 kg/m3), with and without chlorides added to the mixes were designed. Prismatic specimens were cast and exposed to two curing conditions: initially in wet room and then in climatic room. Surface aspect was assessed by visual analysis with the use of a classification criteria. Results showed that the chloride added to the mixes induced a damage related to the superficial aspect whereas the specimens without chlorides presented no sign of corrosion over time.

Highlights

Fibre reinforced cementitious composite (FRCC) is a term commonly used for a broad class of materials with optimized properties
Despite an increased use of steel fibres in high-performance steel fibre reinforced composites (HPFRCC) structures, some doubts remain regarding their resistance to corrosion and durability
The main objective of this paper is to study how chloride affects uncracked HPSFRCCs specimens in terms of surface aspect focussing on fibre corrosion mechanisms

Summary

Introduction

Fibre reinforced cementitious composite (FRCC) is a term commonly used for a broad class of materials with optimized properties. The improved properties of FRCCs increased the use of such materials in structural engineering applications. The advantages of using fibres in structural applications increased the research on SFRC about four decades ago (BRANDT, 2008; JOHNSTON, 1982; MINDESS, 2007; NAAMAN, 2000). FRCCs consist of two basic components: a cementitious base material called matrix, which is reinforced by either steel or synthetic fibres (TRÜB, 2011). Despite an increased use of steel fibres in high-performance steel fibre reinforced composites (HPFRCC) structures, some doubts remain regarding their resistance to corrosion and durability. The high amount of fibres, steel fibres, may lead to some reduction in the chloride penetration resistance of concrete (AFROUGHSABET; BIOLZI; OZBAKKALOGLU, 2016)

Objectives

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Results