Impact of superplasticizer concentration and of ultra-fine particles on the rheological behaviour of dense mortar suspensions

被引:64
作者
Artelt, C. [1 ]
Garcia, E. [2 ]
机构
[1] Ctr Rech, Lafarge, F-38291 St Quentin Fallavier, France
[2] Lafarge Granulats, F-92454 Issy les Moulineaux, France
关键词
mortar; shear thickening; workability; superplasicizer; ultra-fine particles; steric interactions; Van der Waals interactions;
D O I
10.1016/j.cemconres.2008.01.010
中图分类号
TU [建筑科学];
学科分类号
0813 ;
摘要
This work aims at investigating the impact of the addition of superplasticizer and of ultra-fine particles, namely of silica fume and of precipitated titania, on the theological behaviour of water-lean mortar pastes. The pastes are characterised in terms of their spread, their flowing behaviour and by means of performing a shear test, giving access to viscosity/shear gradient correlations. Adding superplasticizer is shown to shift the onset of shear thickening of the referring pastes to higher shear rates and to attenuate its otherwise rapid evolution, possibly by means of favouring steric particle-particle interactions. The workability of these mortars, which is characterised in terms of spread values and draining, is also improved. For the case of fly ash based mortars, adding ultra-fine particles is another way of (slightly) "retarding" shear thickening and of attenuating its evolution, possibly because of resulting in - on the average - lower hydrodynamic forces and reduced attractive Van der Waals interactions between particles. However, at the same time these mortars are characterised by a worsening in workability which is attributed to the huge amount of surface area provided by the ultra-fines. (C) 2008 Elsevier Ltd. All rights reserved.
引用
收藏
页码:633 / 642
页数:10
相关论文
共 26 条
[1]   On the relevance of accounting for the evolution of the fractal dimension in aerosol process simulations [J].
Artelt, C ;
Schmid, HJ ;
Peukert, W .
JOURNAL OF AEROSOL SCIENCE, 2003, 34 (05) :511-534
[2]   SHEAR-THICKENING (DILATANCY) IN SUSPENSIONS OF NONAGGREGATING SOLID PARTICLES DISPERSED IN NEWTONIAN LIQUIDS [J].
BARNES, HA .
JOURNAL OF RHEOLOGY, 1989, 33 (02) :329-366
[3]   Reversible shear thickening in monodisperse and bidisperse colloidal dispersions [J].
Bender, J ;
Wagner, NJ .
JOURNAL OF RHEOLOGY, 1996, 40 (05) :899-916
[4]  
BONNEAU O, 2000, RIL P PRO 13 2 INT R
[5]   Influence of silica fume on the workability and the compressive strength of high-performance concretes [J].
Duval, R ;
Kadri, EH .
CEMENT AND CONCRETE RESEARCH, 1998, 28 (04) :533-547
[6]  
Gartner E M, 2002, STRUCTURE PERFORMANC, P57
[7]  
GEYMAYER H, 1995, ZEM-KALK-GIPS, V48, P86
[8]   Effect of attractions on shear thickening in dense suspensions [J].
Gopalakrishnan, V ;
Zukoski, CF .
JOURNAL OF RHEOLOGY, 2004, 48 (06) :1321-1344
[9]   DISCONTINUOUS AND DILATANT VISCOSITY BEHAVIOR IN CONCENTRATED SUSPENSIONS .2. THEORY AND EXPERIMENTAL TESTS [J].
HOFFMAN, RL .
JOURNAL OF COLLOID AND INTERFACE SCIENCE, 1974, 46 (03) :491-506
[10]   DISCONTINUOUS AND DILATANT VISCOSITY BEHAVIOR IN CONCENTRATED SUSPENSIONS .1. OBSERVATION OF A FLOW INSTABILITY [J].
HOFFMAN, RL .
TRANSACTIONS OF THE SOCIETY OF RHEOLOGY, 1972, 16 (01) :155-&