Effect of Shrinkage-Reducing on Early-Age Concrete Poured with Controlled Permeability Formwork

In this article, total shrinkages of early-age concrete specimens, which formed by controlled permeability formwork (CPF) liner and normal formwork, were obtained by non-contact contractometer test, and the results show that shrinkage amounts before initial setting and swelling amounts can be distinguished. Compared with ordinary specimens whose water-binder ratio dosage varied from 0.50 to 0.35, total shrinkage of specimens poured by CPF liner reduced from 76 percent to 87 percent. The study also demonstrated that evident differences on shrinkage-reducing depend on water retention of CPF liner, which can contribute researchers to understand the shrinkage-reducing working mechanism and improve of CPF liner properties.