EVALUATION OF THE LONG-TERM PROPERTIES OF CONCRETE

Variations in concrete compressive strength, flexural strength, and modulus of elasticity with time are discussed. Concrete specimens made from five types of portland cement, portland blast-furnace slag cement, portland-pozzolan cement and air-entraining cement were tested at ages between 1 day and 34 years. Relationships between the compressive strength at various ages and the 28-day compressive strength are developed for specimens stored in moist and dry environments. Flexural strength and modulus of elasticity are related to the compressive strength.