M. Naderi,
Volume 3, Issue 1 (3-2005)
Abstract
Having observed the costly failures of different cutoff walls, that had been constructed
according to the mix design specified by reputable consultants in Iran, a research programme was
conducted to study the effects of constituent materials on the properties of plastic concrete. The
main properties, such as compressive strength, biaxial and triaxial strains, permeability, and
modulus of elasticity have been investigated using different mixes, obtained from prototype
production line plant, situated on site, because it was realized that the site production line and the
systems employed have major effects on the properties of plastic concrete. Statistical analysis of
the results, revealed the coefficients of influence of main constituent materials of plastic concrete
namely cement, bentonite, aggregate and water on its compressive strength and modulus of
elasticity. Having realized the cancelling effects of bentonite and aggregates on the measured
properties, some equations relating the quantities of cement and water to the compressive strength
and modulus of elasticity are introduced. Effects of clay and hydrated lime powder, as fillers were
also investigated leading to the proposal of limits for their safe and economic use. Since most of
the cutoff walls are buried structures, failure strains under both uniaxial and triaxial tests, with
values of cohesion and internal friction, are also presented in this paper.