Title: A Simple Model to Explain Compressive Strength of High-Performance Concrete

Author(s): D. de Araujo Dafico and L.R. Prudencio, Jr.

Publication: Symposium Paper

Volume: 207

Issue:

Appears on pages(s): 139-150

Keywords: compressive strength; high performance concrete; mathematical models; mix design method; pozzolan

DOI: 10.14359/12387

Date: 10/7/2002

Abstract:
A model to explain the compressive strength of high-performance concrete was developed using multiple linear regression correlating the compressive strength and variables representing volume ratios of paste materials. The data used to develop and validate the model came from a wide range of binary and ternary silica fume, rice husk ash and fly ash concretes that were made by Isaia with the same set of materials. In such tests, the water-cementitious materials ratio by mass varied from about 0,30 to about 0,50, with rates of cement replacement by pozzolan by mass from 0 to 50 %. The 3, 7, 28, and 91 days compressive strengths of 39 different concrete mixtures were measured. High correlation indices were found in most of studied regressions and the accuracy of the predicted values of compressive strength can be considered very good, specially when obtained from a set of concretes made with the addition of just one kind of pozzolan. In this case, the mean difference the addition of just one kind of pozzolan. In this case, the mean difference between the experimental and the predicted values were 0.4 MPa at the age of 28 days.