Pumping of concrete is a daily applied process, providing the possibility of continuously filling a formwork. Reports have been created dealing with the composition and the workability of the concrete, with the maximal discharge and pressures, with the characteristics of pumps and pipes, ... On the other hand, only a very few fundamental scientific studies on this topic are available.
In case of self compacting concrete (SCC), the same rules, valid for traditional concrete (TC), are applied. On the other hand, the verification of these rules, or new rules, are not reported (yet). SCC is considered as a special case of TC, having an advantageous composition for the pumping process, which should simplify the pumping and reduce the problems.
This paper shows the results from a series of pumping tests. After a description of the equipment is provided, a set of surprising results is presented : SCC causes higher pressure losses, compared to TC. Further results will prove the existence of a less viscous layer near the wall, a temperature increase inside the concrete equivalent to the pressure loss and the importance of thixotropy.
[1]
Jon Elvar Wallevik,et al.
Rheology of Particle Suspensions: Fresh Concrete, Mortar and Cement Paste with Various Types of Lignosulfonates
,
2003
.
[2]
Nicolas Roussel,et al.
A thixotropy model for fresh fluid concretes: Theory, validation and applications
,
2006
.
[3]
D. Feys,et al.
Fresh self compacting concrete, a shear thickening material
,
2008
.
[4]
Mfw Schwing,et al.
PUMPING OF CONCRETE
,
1970
.
[5]
Geert De Schutter,et al.
Evaluation of gravitational flow tests with self-compacting concrete
,
2008
.
[6]
Geert De Schutter,et al.
Full scale pumping tests on SCC: application of the modified Hattori-Izumi theory
,
2009
.