Rheology of Cement Mortars with Crushed Fine Aggregates of Different Lithological Types

• Published in: Tu mu gong cheng yu jian zhu 2014-09, Vol.8 (9), p.1110-1120
• Main Author: Elton Bauer Carla Cristina Nascimento Santos Pereira Joao Henrique da Silva Rego Claudio Henrique deAlmeida Feitosa Pereira Eliane Kraus Castro
• Format: Article
• Language: English
• Subjects: 天然砂; 屈服应力; 岩性; 岩石类型; 水泥砂浆; 流变学特性; 碎石; 细集料
• ISSN: 1934-7359; 1934-7367
• DOI: 10.17265/1934-7359/2014.09.003

Crushed fine aggregates are widely used for full or partial replacement of natural sands in concretes. The crushed sands present different characteristics from the natural sand, especially if taking into account the content of microfine particle, the distribution of particle sizes, the shape features, besides the different lithological origin. From the rheological point of view, the crushed sands frequently provide mixtures with high yield stress, high viscosity, high cohesion and internal friction, which hinders its use in concrete. This study is focused on the evaluation of the rheological behavior of concrete mortar phase when using different lithological types of crushed sand in total replacement of natural sand. The lithological types surveyed were granite, calcitic limestone, dolomite limestone and mica schist. Each of these sand types was studied in two ways： in natura and with adjusted grading curve. The results show the best performance of calcitic limestone providing lower viscosities and lower yield stress in mortars.