Title:
Formulation of Self-Compacting Concrete with Limestone Tuff and Study of the Parameters Influence on the Responses
Author(s):
Boulkhiout M., Benna Y., Bali A., Benyoussef E.H., Silhadi K.
Publication:
Symposium Paper
Volume:
362
Issue:
Appears on pages(s):
202-214
Keywords:
fresh properties, limestone tuff, mechanical properties, mixture proportions, sand, self-compacting concrete
DOI:
10.14359/51740884
Date:
6/5/2024
Abstract:
This work investigates the influence of partial substitution of sand, which is becoming scarce, by the fines-rich limestone tuff sand on the fresh and mechanical performances of self-compacting concrete (SCC). A full three-factor design was applied to demonstrate the individual and combined effects of cement dosage, tuff substitution rate, and superplasticizer dosage on the spread, sieve stability and L-box fill rate, and compressive strength of the different formulated SCC. The SCCs were formulated with Algerian Htattba tuff containing 34% fines, at substitution percentages ranging from 35 to 55%. The limestone tuff sand proved to be well suited for use in the formulation of the SCCs, which are expected to perform well in the fresh state. The use of limestone tuff sand at high substitution rates resulted in a fluid, stable SCC that flowed perfectly through the iron bars of the Lbox without blockage and complied with the recommendations of the French Association of Civil Engineering, AFGC. The main influences observed after analysis of the responses obtained highlighted the predominant effect of the superplasticizer followed by the non-negligible positive effect of the limestone tuff, on the fresh characteristics of the formulated SCC. The first results show that the introduction of limestone tuff up to a substitution rate of 55% gives a consequent workability of 690 mm and a good compressive strength of about 40 MPa. It should be noted that a 55% substitution rate presents an undeniable economic and environmental interest by reducing the quantity of sand considered a "noble material" which is less and less available.