ABSTRACT
The properties of hardened concrete involve primarily its strength and modulus of elasticity; other properties required often are the drying shrinkage, creep, permeability, bond, and durability. This chapter presents data on mechanical properties and permeability of condensed silica fume concrete. The water demand of silica fume concrete is directly proportional to the amount of silica fume if the slump of concrete is maintained constant by increasing the water content rather than by using a superplasticizer. The drying shrinkage of concrete is controlled by the volume fraction of the cement paste, and volume fraction, stiffness, and maximum size of the aggregate. R. Johansen performed shrinkage measurements on concrete prisms that were exposed to a drying environment immediately after demolding, and after 28-day moist curing. Permeability of concrete determines its resistance to chemical attack. A number of investigators have studied the bond characteristics between aggregates and silica fume-based cement pastes and mortars.
