Title:
Effect of Temperature on Rheological Properties of Superplasticized Cement Mortars
Author(s):
J. Golaszewski
Publication:
Symposium Paper
Volume:
239
Issue:
Appears on pages(s):
423-440
Keywords:
fresh concrete; mortars; rheology; superplasticizer; temperature; workability
DOI:
10.14359/18394
Date:
10/1/2006
Abstract:
The methodology and the results of the investigation into influence of the temperature on the rheological properties of fresh mortars containing different superplasticizers and cements are presented, and discussed in this paper. Influence of temperature was studied using Two Point Workability Test (TPWT) and modified standard mortars acc. PN EN 196-1 which can be also considered as a model of concrete. The following factors were taken into consideration: mix temperature (10, 20, 30oC), specific surface of cement (320, 370, 420 m2/kg), C3A content in cement (2, 7, 12%), Na2Oe content in cement (0.3, 0.7, 1.1%), and superplasticizer type (polyeter and polycarboxylate acid based superplasticizers with different molecular weight and polymer structure). The obtained results show that temperature strongly influences rheology of mortars and that the nature and range of this influence changes in wide range depending on the properties of cement and superplasticizer used. Basic effects of temperature influence on rheological parameters of mortars in relation to mentioned above factors are presented and discussed. These relationships can be applied to control workability of fresh mortar and concrete. Discussion about the results covers also mechanism of temperature influence on rheological properties of mortars. It is concluded that compatibility of cement - SP system must be tested taking into account temperature. TPWT made on mortars makes possible to select a cement - superplasticizer system that is optimal in given temperature, and to collect data necessary for control of fresh mortar and concrete workability in various temperature conditions.