Statistical variations and new correlation models to predict the mechanical behaviour of the cement mortar modified with silica fume

Abstract

ABSTRACT Despite many of the research studies on the effect of the silica fume content on the mechanical properties of the cement mortar, there has not been a comprehensive study investigating the effect of silica fume content, curing time and water to cement ratio on the compressive, tensile and flexural strengths of cement mortar. In this study investigates the subject which could be beneficial for building and construction field. More than 1000 data on the mechanical properties of the cement mortar modified with different percentages of silica fume varied from 5% to 55% (by dry weight of the cement) collected from the literature. The statistical analysis, modelling and non-linear regression analysis were performed on the collected data. The water to cement ratio (w/c) ranged between 0.20% and 1% and the compressive strength, tensile strength and flexural strength of cement mortar modified with silica fume up to 90 days of curing were ranged between 2.5MPa and 87 MPa; 2 MPa and 6.8 MPa; and 1.2 MPa and 9.2 MPa, respectively. Vipulanandan correlation model was used and compared with the Hoek-Brown model to correlate the mechanical properties of cement mortar modified with silica fume. The Vipulanandan correlation model has a lower root mean square error (RMSE) compared to the Hoek-Brown model. The results of the present study showed that there is a good relationship between the compressive strength with flexural strength and tensile strength for cement mortar modified with silica fume. Based on the data analysis the per cent of silica fume up to 55% had the lowest effect on increasing the compressive strength compared with w/c and curing time.