Volume 20, Issue 1 (January 1992) Comparison of Fine Particle
Colemanite and Boron Frit in Concrete for Time-Strength
Relationship The element boron, when added to concrete, has
proved effective in shielding neutron particles by absorbing the
neutron and emitting a low-energy gamma ray. The various boron
additives used with concrete can severely retard the set time
and strength gain. An advantage to using small particle size
boron is that the smaller grain size provides better boron
disbursement within the concrete matrix to absorb neutrons.
However, boron additives of powder consistency are usually not
used due to the greater potential of forming chemical solutions
that act as a retarder in the concrete. Research has shown that
the amount of boron additives in concrete can be reduced
significantly if fine grain particles can be successfully
incorporated into the concrete matrix. The purpose of this study
is to compare strength gain characteristics of concrete mixes
containing various quantities of fine grain