Shrinkage, Creep, and Creep Recovery of Gap-Graded Versus Continuously-Graded Concrete

摘要

The work presents a comparative study of shrinkage, creep, and creep recovery characteristics of gap-graded versus continuously-graded concretes according to ASTM Standard Methods on 48 specimens made out of 16 concrete mixes of target strength range from 4500 to 7500 psi. Experimental results obtained for different maximum sizes of coarse aggregate and different concrete compressive strengths of gap-graded air-entrained concrete are compared with those of equivalent continuously-graded air-entrained concrete. The sustained load on the creep specimen was removed at the end of 365 days and the creep recovery behavior for both gap-graded and continuously-graded concretes upon unloading was observed. Then they were reloaded to determine the effect of this load cycle on creep. Elastic modulus and ultimate compressive strength tests were conducted to determine the effect of age and sustained load on these parameters. (Author)