Microstructure And Durability Of Mortars Modified With Medium Active Blast Furnace Slag/Microstructure et durabilité des mortiers modifiés avec un laitier de haut fourneau

Abstract: Mechanical characteristics and durability properties of blast furnace slag cement composites largely depend on the hydraulic activity of the slag. In this paper, a Granulated Blast Furnace Slag with a low reactivity index is used in modifying mortar composition. Microstructure and durability of mixes containing 0%, 30% and 50% of slag as substitution to OPC are respectively compared and analyzed. Water porosity, Mercury Intrusion Porosity and pore size distribution are studied after 28, 90 and 360 days of wet curing. A qualitative microstructure analysis of mortars is proposed with Scanning Electron Microscope (SEM). The durability of mortar is evaluated through capillary water absorption and chloride diffusion tests. The results indicate a finer porosity and lower water absorption for slag mortars at old ages (90 and 360 days). Moreover, lower chloride diffusion for 50% blast furnace slag substitution is observed. Resume: Les caracteristiques mecaniques et les proprietes de durabilite des composes du ciment a base de laitier de haut fourneau dependent fortement de l?activite hydraulique du laitier. Dans ce travail, un laitier granule de haut fourneau, avec un indice de reactivite bas est utilise pour modifier la composition du mortier. La microstructure et la durabilite des melanges contenant 0%, 30% et 50% de laitier comme substitution du ciment portland sont comparees et analysees respectivement. La porosite, la porosite par intrusion de mercure et la distribution de tailles de pores sont etudiees apres 28, 90 et 360 jours de cure. Une analyse qualitative de microstructure des mortiers est proposee avec une microscopie electronique a balayage. La durabilite des mortiers est evaluee par des tests d?absorption d?eau capillaire et de diffusion de chlorures. Les resultats indiquent une porosite plus fine et une absorption d?eau inferieure pour les vieux mortiers a base de laitier (90 et 360 ans). De plus, une diffusion inferieure de chlorures de 50 % de substitution du laitier de haut fourneau est observee.

[1]  Eun Kyum Kim,et al.  An experimental study on corrosion resistance of concrete with ground granulate blast-furnace slag , 2005 .

[2]  J. Grandet,et al.  Evolution comparee des porosites des mortiers de ciment au laitier et des mortiers de ciment portland , 1989 .

[3]  Tinus Pulles,et al.  EPER Pollutant Emission Register , 2004 .

[4]  F. Glasser.  Properties of cement waste composites , 1996 .

[5]  Y. Cai,et al.  Study of chloride binding and diffusion in GGBS concrete , 2003 .

[6]  V. M. Malhotra,et al.  Durability of Concrete , 2011 .

[7]  R. F. Feldman.  Significance of Porosity Measurements on Blended Cement Performance , 1983 .

[8]  Abhijit Mukherjee,et al.  INVESTIGATION OF HYDRAULIC ACTIVITY OF GROUND GRANULATED BLAST FURNACE SLAG IN CONCRETE , 2003 .

[9]  H. Moon,et al.  Relationship between average pore diameter and chloride diffusivity in various concretes , 2006 .

[10]  Nick R. Buenfeld,et al.  Factors influencing chloride-binding in concrete , 1990 .

[11]  C. Perlot,et al.  Influence of cement type on transport properties and chemical degradation: Application to nuclear waste storage , 2005 .

[12]  An Cheng,et al.  Influence of GGBS on durability and corrosion behavior of reinforced concrete , 2005 .

[13]  Luc Courard,et al.  Durability of mortars modified with metakaolin , 2003 .

[14]  Ravindra K. Dhir,et al.  Chloride binding in GGBS concrete , 1996 .

[15]  Mark Alexander,et al.  Durability performance of concrete containing condensed silica fume , 1999 .

[16]  Hui-sheng Shi,et al.  Influence of mineral admixtures on compressive strength, gas permeability and carbonation of high performance concrete , 2009 .

[17]  R. Černý,et al.  High performance concrete containing lower slag amount: A complex view of mechanical and durability properties , 2009 .

[18]  A. Neville.  Properties of Concrete , 1968 .

[19]  Mehmet Gesoğlu,et al.  A study on durability properties of high-performance concretes incorporating high replacement levels of slag , 2008 .

[20]  G. Ye,et al.  Simulation of connectivity of capillary porosity in hardening cement-based systems made of blended materials , 2009 .

[21]  A. K. Suryavanshi,et al.  EVALUATION OF RAPID CHLORIDE PERMEABILITY TEST (RCPT) RESULTS FOR CONCRETE CONTAINING MINERAL ADMIXTURES , 2000 .

[22]  Erin E. Dooley,et al.  European Pollutant Emission Register , 2004 .

[23]  E. Samson,et al.  Durability of concrete — Degradation phenomena involving detrimental chemical reactions , 2008 .