Early age properties of green concrete containing high mineral additions

Title: Early age properties of green concrete containing high mineral additions
Author(s): Muhammad Irfan Ahmad Khokhar, Stéphanie Staquet
Paper category : conference
Book title: 2nd International Symposium on Service Life Design for Infrastructures
Editor(s): K. van Breugel, Guang Ye, Yong Yuan
Print-ISBN: 978-2-35158-096-7
e-ISBN: 978-2-35158-097-4
Publisher: RILEM Publications SARL
Publication year: 2010
Pages: 901 - 909
Total Pages: 9
Nb references: 25
Language: English

Abstract: It is very essential to study the early age hydration of concrete when using high content of mineral additions in green concrete, since the development of the mechanical properties of green concrete is slower than one of the OPC concrete. Setting and hardening and rate of heat evolution are main early age concrete properties. Ultrasonic wave measurements were used to monitor the setting and hardening behaviour since casting time. Heat of concrete hydration was studied by measuring the temperature increase under adiabatic condition. Tests were carried out at 20°C for nine mixture proportions: a reference concrete with Portland cement, five green concretes with various proportions of one blast furnace slag or fly ash and three green concretes with a combination of limestone microfiller with blast furnace slag or fly ash.
The use of limestone microfiller allowed decreasing the water/binder ratio of the green concretes by keeping the same rheology. Consequently, the initial and final settings times were reduced for concretes with limestone microfiller. High slag and fly ash contents have significant effect on the time of appearance of the main heat evolution peak. Characteristic of heat evolution of green concrete was found to be strongly dependent on the replacement level of mineral additions. It was also found that using mineral addition as cement replacement resulted in a reduction on the maximum temperature rise.

Online publication: 2011-04-20
Publication type : full_text
Public price (Euros): 0.00