KALMATRON
Believe it - there is complete hydration! KF-A Second
Asia/Pacific Conference on Durability of Buildings Systems: Harmonised
Standards and Evaluation, Bandung, Indonesia, 10-12 July 2000 a New Shrinkage Controlling Admixture
for
Structural Concrete Dr. R. Sri Ravindrarajah, H. Kincses, and Professor
S. L. Bakoss Centre
for Built Infrastructure Research, University of Technology, Sydney
Abstract Concrete producers
use a number of admixtures to modify the properties of fresh and
hardened concrete mixes to meet the varying specification
requirements by the construction industry. Technological
advancements in the admixture technology lead to the development of
several admixture types to control setting times, reduce
permeability, control heat liberation, improve the development of
strength and control the time-dependent strains. Drying shrinkage is
an important structural property of concrete because of its effects
on concrete cracking and loss in pre-stress concrete members.
Although use of water-reducing admixtures is capable of reducing
water content in the mixes, its effect on shrinkage is limited. In
addition, shrinkage-limited cement is used to limit the shrinkage of
concrete. A new admixture, known as Kalmatron® KFA, in a powder form
is originally developed in former USSR. It has the capacity of
modify the characteristics of the concrete mixes and redefines the
slump requirements of the concrete mix. It has the general tendency
to improve the workability of a concrete mix. This paper reports the
results of an experimental investigation into the effectiveness of a
new admixture in controlling the drying shrinkage of structural
concrete. The results indicate that the Kalmatron® KFA has reduced
the drying shrinkage of concrete by about 25% compared to control
mix. In addition, Kalmatron® KFA is capable of replacing the silica
fume without effecting the development of strength. However, the
resultant mix has significant reduction in drying shrinkage. |
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