Water-cement relationships in extreme vertex design applied to mortar | [Relaciones agua-cemento en diseño de vértices extremos aplicado a mortero]

Abstract

The present research deals with the application of the water/cement relations in extreme vertices design for mortars to delimit an operability zone in the simplex. Three components were used: water, Portland pozzolanic cement, and fine sand, and the responses were compressive strengths at 24 h, 3, 7 and 28 days, and mortar fluidity. The performed analysis revealed that the water/cement relations can be modeled according to the principles of the experimental mix design and they can be used as constraints for the application of the extreme vertices design. Results showed that water/cement ratios have delimited ranges. The mathematical models explain the response with Raj2greater than 85% and with values of p<0.009. In addition, results proved the existence of a feasible operability zone in the simplex for mortars of which the ratio water/cement varies in the range 0.3≤x1/x2≤0.9, with the resistances varying between 75.67 to 473.35 kg/cm2 at 28 days and the fluidity from 45.15 to 150%. The mortar cost in the operability zone varies from 65.94 to 229.73$ per m3, enabling the constructor to select the mortar corresponding to the technical needs.

Keywords

• extreme vertices design
• water-cement relationship
• mortar
• mathematical model