This study will determine the following characteristics on concretes with lightweight aggregates from six sources:
1) Density will be measured at the fresh state (ASTM C 138), oven-dry state (ASTM C 567) and equilibrium state (ASTM C 567).  The measured equilibrium density will be compared with the calculated equilibrium density.  Equilibrium density is used in the design of concrete elements of structures.
2) The new surface-resistivity test will be evaluated on lightweight concrete, a faster and easier test method for concrete permeability.
3) The splitting test and elastic modulus of lightweight concretes will be determined on the same mixtures with different curing conditions and moisture contents.  These values are important in the design of concrete members of structures.

The accurate knowledge of density, splitting tensile strength and elastic modulus will permit a better understanding of the design assumptions for the lightweight concrete.