Effect of lightweight aggregate type on early-age autogenous shrinkage of concrete

摘要

The effect of lightweight aggregate (LWA) type on the early-age autogenous shrinkage of lightweight aggregate concrete (LWAC) was investigated based on a corrugated tube testing method. The study reveals that the early-age autogenous shrinkage includes liquid phase, skeleton-formational phase and hardening phase, and is also affected by cylinder compression strength and water absorption rate of LWA. For the summation of the early-age autogenous shrinkage of skeleton-formational phase and hardening phase after time-zero, which are concerned with the development of stress in concrete and the resulting cracking, as long as the net water cement ratio or total water cement ratio is kept the same, the LWAC with LWA of higher water absorption rate and lower cylinder compression strength shows larger early-age autogenous shrinkage than the LWAC with LWA of lower water absorption rate and higher cylinder compression strength when the LWA was prewetted. (C) 2016 Elsevier Ltd. All rights reserved.