Estimating the elastic modulus of concrete made with artificially manufactured lightweight aggregates

Discusses the results of a study of the moduli of elasticity of concretes made with artificially manufactured lightweight aggregates subjected to uniaxial compression and uniaxial tension. Two artificially manufactured lightweight aggregates and one normal weight aggregate (for comparison) were used in the investigation. Concrete mixes designed to have compressive strengths varying from 20 MPa to 60 MPa were used in this study. Presents the results of static and dynamic moduli of elasticity, Poisson′s ratio, ultrasonic pulse velocity, compressive strength and tensile strength tests. Observes that the static modulus of elasticity in tension is nearly equal to the static modulus of elasticity in compression at a stress level of one‐third the ultimate stress. Compressive modulus values are shown to be dependent on the stress level and type of modulus, i.e. either secant or tangent. On the other hand, the tensile modulus is not affected by the stress level. The modulus of elasticity of lightweight aggregate concrete is about 60‐70 per cent of that of normal weight concrete. Compares the test results obtained in this study with research work carried out on other lightweight aggregate concretes by other investigators. Also presents the relationships between static modulus of elasticity, dynamic modulus of elasticity, compressive strength, and Poisson′s ratio, and equations for estimating elastic modulus and Poisson′s ratio.