Silica fume-hydrated lime blended cements: contribution of pre-blending to strength development in mortars

ABSTRACT

This paper presents an experimental study on the mechanical properties at 28 days of mortars comprising Condensed Silica Fume (CSF), Hydrated Lime (CH) or both, at various substitution rates and water-to-binder ratios (w/b). An evaluation of the mechanical properties has been carried out using Ultrasonic Pulse Velocity (UPV) tests and compressive/tensile strength tests, to assess CSF, CH and CSF-CH addition and substitution rate effect on strength development. A marked increase in the mechanical properties of the CSF, CSF-CH mortars is noted, with the best results obtained after CSF-CH pre-mixing, reaching 35.71% improvement vs control, highlighting the occurrence of considerable pozzolanic reactions. UPV tests have shown increased velocities for CSF and CSF-CH mixes, transcribing a densification of the matrix. The results of the study seem to indicate that CSF and CSF-CH addition could represent a suitable solution to significantly increase both the mechanical and durability properties of mortars.

KEYWORDS:

• Silica fume
• hydrated lime
• pozzolanic reaction
• UPV

Disclosure statement

No potential conflict of interest was reported by the author.

Additional information

Notes on contributors

Nacim Khelil

Nacim Khelil is a Lecturer in the Department of Civil Engineering at Mouloud Mammeri University, Tizi-Ouzou, Algeria. Mr. Khelil has received his Phd in Materials, Civil and Structural engineering at Paul Sabatier University, Toulouse, France; where he developed an electro-chemical treatment for internal sulfate attack ISF-affected concretes. Mr. Khelil is an active researcher in the field of Materials science. Mr. Khelil scope of research encompasses: the development of more sustainable supplemented cementitious materials, the design and optimisation of ultra-high performance fiber-reinforced concretes (UHPFRC) using locally available materials and the non-destructive evaluation of the mechanical properties of mortars and concretes.