Mortars with nano-SiO2 and micro-SiO2 investigated by experimental design

resumo

This paper reports the effects of nanosilica (nS) and silica fume (SF) on rheology, spread on flow table, compressive strength, water absorption, apparent porosity, unrestrained shrinkage and weight loss of mortars up to 28 days. Samples with nS (0-7 wt.%), SF (0-20 wt.%) and water/binder ratio (0.35-0.59), were investigated through factorial design experiments. Nanosilica with 7 wt.% showed a faster formation of structures during the rheological measurements. The structure formation influences more yield stress than plastic viscosity and the yield stress relates well with the spread on table. Compressive strength, water absorption and apparent porosity showed a lack of fit of second order of the model for the range interval studied. In addition, the variation of the unrestrained shrinkage and weight loss of mortars do not follow a linear regression model. The maximum unrestrained shrinkage increased 80% for nS mortars (7 days) and 54% (28 days) when compared to SF mortars in the same periods. (C) 2010 Elsevier Ltd. All rights reserved.

palavras-chave

CONCRETE INCORPORATING NANO-SIO2; CEMENT MORTAR; NANO-PARTICLES; MICROSTRUCTURE; SILICA

categoria

Construction & Building Technology; Engineering; Materials Science

autores

Senff, L; Hotza, D; Repette, WL; Ferreira, VM; Labrincha, JA

nossos autores

agradecimentos

The authors acknowledge the support of CAPES, Brazil. The authors also thank Weber Portugal, BASF, Elkem, Cimpor for providing raw materials for this work.

Partilhe este projeto

Publicações similares

Usamos cookies para atividades de marketing e para lhe oferecer uma melhor experiência de navegação. Ao clicar em “Aceitar Cookies” você concorda com nossa política de cookies. Leia sobre como usamos cookies clicando em "Política de Privacidade e Cookies".